key: cord-259279-8dspud40 authors: kahveci, zafer; kilinc-balci, f. selcen; yorio, patrick l. title: barrier resistance of double layer isolation gowns date: 2020-10-17 journal: am j infect control doi: 10.1016/j.ajic.2020.09.017 sha: doc_id: 259279 cord_uid: 8dspud40 isolation gowns are one of the crucial pieces of personal protective equipment (ppe) to prevent the migration of microorganisms and body fluids from patients to healthcare personnel and vice versa. underperforming isolation gowns in terms of fluid resistance, could potentially put lives in danger. wearing multiple layers of isolation gowns could theoretically increase the fluid penetration resistance. extraordinary circumstances such as epidemics/pandemics and product recalls, bring extra burden on the health institutions in terms of ppe availability. thus, shortages could occur, and ppe that provides an appropriate level of protection might not be available. therefore, wearing multiple layers of lower barrier level gowns could be assumed as a solution. this study investigates if two-layer lower barrier level isolation gowns meet the barrier effectiveness requirements of a single higher barrier level isolation gown. three ansi/aami pb70 level 2 isolation gowns were tested based on the ansi/aami pb70 standard, in single and double-layer configuration. test results demonstrated that the double layer isolation gown configuration does not always provide equal fluid resistance as the higher level of isolation gown according to results from the aatcc 42 and aatcc 127 standard test methods, which are described in ansi/aami pb70. as of april 9, 2020, the coronavirus disease 2019 (covid-19) pandemic had resulted in 9,282 hcp infections, and among those 27 deaths, in the us alone (1). significant efforts have been employed to develop new materials and manufacturing techniques to meet consumers' design needs and improve barrier protection in recent years. isolation gowns are one of the main pieces of ppe for protecting hcp, patients, and visitors from infectious pathogens. there are many types of isolation gowns in the marketplace which offer varying barrier resistance to blood or other body fluids. isolation gowns are generally classified as disposable or reusable, however mainly disposable gowns are used in the u.s. healthcare in contrast to europe (2) . the building materials and design of the isolation gowns determine the barrier effectiveness. disposable isolation gowns are typically constructed of nonwoven materials, which are made of a wide range of synthetic fibers or in combination with other materials such as plastic films (3). the ansi/aami pb70 (4) standard is currently used to classify gowns according to the liquid barrier performance. the aami pb70 standard includes four standard tests to evaluate the barrier effectiveness of surgical gowns and isolation gowns. based on the results of these standardized tests, four levels of barrier performance are defined, with level 1 being the lowest level of protection, and level 4 being the highest level of protection (table 1 ). the requirements for the design and construction of surgical and isolation gowns are based on the anticipated location and degree of liquid contact, given the expected conditions of use. ansi/aami pb70 identifies certain areas of isolation gowns as critical zones. the critical zones include those areas where direct contact with blood, body fluids, and/or other potentially infectious materials is most likely to occur. according to the standard, for isolation gowns the whole garment is considered a critical zone which includes the seams, but excludes the cuffs, hems, and bindings (3). aami tir 11 is a technical guidance that provides considerations for selecting the protection level of ppe based on the anticipated exposure to potentially infectious fluids (5) . some of the factors important to assessing the risk of exposure in healthcare facilities include source, modes of transmission, pressures and types of contact, and duration and type of tasks. according to the guidance, level 1 to 3 gowns could be used when minimal to moderate fluid exposures are expected such as, simple biopsies, ear, nose, and throat procedures, as well as mastectomies, gastrointestinal, arthroscopic orthopedic, and endoscopic urological procedures. thus, identifying the expected fluid amount and duration of exposure has great importance when selecting the appropriate gown. although, selection of an appropriate gown depends on anticipated fluid exposure, it may be based on the availability of a gown at the specific level of protection within the healthcare institution. during times of pandemics or product recalls, ppe shortages could occur (6) (7) (8) . when gowns with higher levels of protection are not available, hcp may resort to wearing gowns with lower levels of protection. this study aims to investigate if wearing a double layer of lower level there are several studies that show benefits of double-gloving, as demonstrated by guo et al. where they provided evidence of advantages of using double layer glove configuration compared to single layer (9) . in addition, previous national institute for occupational safety and health (niosh) research showed the benefit of double gloving in terms of gown-glove interface barrier efficacy (11) . although double-gloving is not directly related to wearing multiple layer gowns, since generally double-gloving is considered advantageous if a puncture or imperfection potentially occurs or exists in the first layer, where both layers of gloves are expected to be impervious to fluid, it is worth to mention, because double-gloving could be thought as an evidence-based justification for wearing multiple layer isolation gowns. an experimental laboratory study was designed to investigate the impact of double layer gown configuration on the fluid resistance provided by the system using isolation gowns. three commonly used (labeled as a, b, and c) ansi/aami level 2 isolation gown models were selected and tested in single layer and double layer configurations in accordance with ansi/aami pb70 requirements. ansi/aami pb70 requires testing the gown critical zones using aatcc 42 (12) and aatcc 127(13) standard test methods. all of the gown models had a medium weight multilayer nonwoven fabric design and heat-sealed seams. some of the other specifications of the gowns are listed in the table 2 . the aatcc 42 (water resistance: impact penetration test) determines the ability of a material to resist water penetration under spray impact. the test sample is clamped over pre-weighed blotter paper at a 45 angle and 500 ml of water is released from a spray head. the total water penetration is calculated and reported in grams by subtracting the weight of the dry blotter paper from the weight of the blotter paper after the test. higher weights in grams represent lower water resistance. according to ansi/aami pb70, this testing should be conducted on samples taken from the critical zones, which correspond to the entire gown for the isolation gowns, including sleeve seams and points of attachments. ten specimens from two of the critical zones (chestcontinuous regions and sleeve seams) were tested for three isolation gown models. in total, 60 aatcc 42 tests were conducted. the aatcc 127 (water resistance: hydrostatic pressure test) determines the ability of a material to resist water penetration under increasing water pressure. the test sample is clamped in place, and the hydrostatic pressure is increased at a rate of 60 mbar/min until visible penetration of water droplets is observed. thus, higher hydrostatic pressure represents higher water resistance. similar to aatcc 42, ten specimens from two of the critical zones (chestcontinuous regions and sleeve seams) were tested for three isolation gown models. in total, 60 aatcc 127 tests were conducted. three ansi/aami level 2 isolation gown models (a, b, c) were tested in single layer and double layer configurations using two water resistance test methods; aatcc 42, and aatcc 127, which were previously defined. the test specimens were matched up from different samples for the same gown model when creating double layer configurations. aatcc 42 standard testing measures the total amount of water that penetrated through the gown fabric onto the blotter paper in grams; thus, higher numbers represent lower water resistance of fabric. whereas, aatcc 127 hydrostatic test measures the water penetration resistance under constant hydrostatic pressure in cmh 2 o; therefore, high numbers in the test results represent higher water resistance of the fabric. in total, 120 experiments were conducted to analyze the effects of gown model according to the aatcc 42 impact penetration results, fluid resistance of a, b, and c continuous region samples was increased about 89%, 97%, and 91%, respectively, when comparing single versus double layer configuration. however, the aatcc 127 hydrostatic resistance test resulted in about 62%, 26%, and 29% increase in the fluid resistance, respectively. these results could be attributed to prolonged high-pressure water contact in the aatcc 127 test, in contrast to the single water spray in the aatcc 42, in which the outer fabric layer could resist the initial water impact causing the water to lose its initial impact energy resulting in a small number of droplets reaching the second inner layer. although, there was an increase in the resistance performances of all models, most of the time double layer configurations of these of health care personnel with covid-19 -united states a quantitative, qualitative, and critical assessment of surgical waste. surgeons venture through the trash can isolation gowns in health care settings: laboratory studies, regulations and standards, and potential barriers of gown selection and use liquid barrier performance and classification of protective apparel and drapes intended for use in health care facilities selection of surgical gowns and drapes in health care facilities world health organization; 2020. 7. begging for thermometers, body bags, and gowns: u.s. health care workers are dangerously ill-equipped to fight covid-19: time strategies to optimize the supply of ppe and equipment: centers for disease control and prevention is double-gloving really protective? a comparison between the glove perforation rate among perioperative nurses with single and double gloves during surgery effect of single-versus doublegloving on virus transfer to health care workers' skin and clothing during removal of personal protective equipment critical investigation of glove-gown interface barrier performance in simulated surgical settings american association of textile chemists and colorists american association of textile chemists and colorists key: cord-007828-c7jxj74b authors: memish, ziad a.; al-tawfiq, jaffar a. title: middle east respiratory syndrome coronavirus infection control: the missing piece? date: 2014-11-25 journal: am j infect control doi: 10.1016/j.ajic.2014.08.003 sha: doc_id: 7828 cord_uid: c7jxj74b nan since the initial occurrence of middle east respiratory syndrome coronavirus (mers-cov) in 2012, 1,2 the disease had caused 837 cases, with a case fatality rate of 34.7%. 3 as with any emerging infectious diseases of pandemic potential there is a concern of the global spread of the disease. it is therefore the first priority of the global public health community to develop and implement the required infection control practices to prevent the dissemination of these emerging organisms within health care facilities (hcfs) and worldwide based on the best available evidence and previous experience with similar or related groups of pathogens. the world health organization (who) through its expert technical committees was prompt in developing its first infection control guidelines based on available knowledge on the new emerging virus, but it mostly drew on experience from a similar virus, severe acute respiratory syndrome coronavirus (sars). these guidelines were updated based on accumulating experience from reports of mers-cov cases and clusters in the community and hcfs in affected countries and regions. this became particularly important with the third and largest wave of hcf-associated mers-cov cases reported from the kingdom of saudi arabia and united arab emirates in april-may 2014. 4 the initial cases were reported in hospital a in jeddah with subsequent appearance of cases in 3 other hospitals. during the initial jeddah outbreak, there were 5 involved hospitals: a-e. hospital a had 3 cases: a community case and 2 health care workers (hcws) assumed to have been infected from the first case. hospital b had 2 community-acquired infections. hospital c reported 1 community-acquired case. hospital d had 1 fatal case in an hcw. the source of infection was believed to be the community; however, hospital-acquired infection could not be ruled out. hospital e was where the main nosocomial cluster occurred. hospital e is a large and busy referral teaching hospital where staff share accommodation. the emergency room is busy with an occupancy rate of 578% for the 76 emergency beds. there were initially 4 community cases reported. extensive screening of their contacts among hcws and family members identified 26 laboratory-confirmed cases among hcws (19 were asymptomatic), 1 family member, and 6 patient contacts. careful review of the recent increase in the number of cases revealed that about 25% were among hcws. 4 of the initial 128 recent mers-cov infected patients in jeddah, kingdom of saudi arabia, most (60%) were infected in the health care setting. of those, 39 were hcws. 5, 6 these 128 cases occurred between february 17, 2014, and april 26, 2014, 6 and were treated in 14 hospitals in jeddah. most hospitals had 1 or 2 patients, and hospital e had 45 cases. 6 of these cases, 33% were primary cases. 6 of the 128 cases, 60% (including 39 hcws) were from health careeacquired infection. 6 an extensive screening of contacts showed that 7 of 554 household contacts (1.3%) were polymerase chain reaction positive for mers-cov 6 compared with 3.03% of 462 family contacts screened during 2012-2013. 7 because the largest percentage of secondary human-to-human transmission occurs in hcfs, 8 the critical question remains of whether the recent large multi-hcf clustering in 2014 was caused by failure of the evidence-based recommended infection control measures outlined by the who or failure of its strict application in the affected facilities. the who continues to stress 3 different approaches to infection control: contact precautions, droplet precautions, and airborne isolation. 9 the use of contact precautions is thought to be needed because of the presence of diarrhea and vomiting in approximately 30% of cases. 2, 10, 11 although, there was no documented transmission of mers-cov through this route, the virus was isolated from stool in a few patients. 12 in addition, studies investigating environmental stability of mers-cov have revealed that mers-cov was stable at different temperature and humidity conditions and could still be recovered after 48 hours, which supports the potential of mers-cov to be transmitted via contact or fomite transmission because of prolonged environmental presence. 13 drawing on data from similar viruses, the potential transmission of viral respiratory infections by contacts was highlighted previously. 14 because mers-cov is similar to sars in many aspects, patients with sars had high virus concentrations and prolonged virus excretion in stools. [15] [16] [17] assessment of infection control practices applied in the affected hcfs during the peak of the outbreak conducted by local and international agencies concluded that the jeddah outbreak was related to poor compliance with the recommended basic infection control measures. 18 the finding is supported by similar observations from sars. during the sars outbreak, the infection in health care settings was further exaggerated by overcrowding, short distance between patient beds, inadequate ventilation, use of aerosol-generating techniques, and during cardiopulmonary resuscitation. 19, 20 the who report on infection control measures for severe acute respiratory infections also elucidated the major risks associated with high-risk aerosol-generating procedures. 9 the recommendations to use droplet precautions for all patients admitted with confirmed or suspected mers-cov, except in aerosol-generating procedures, come from the understanding of the al-hasa outbreak. 2 during that outbreak, a total of 23 patients were recorded across 4 health care settings. the outbreak was controlled with implementation of the basic infection control measures without airborne isolation. 2, 21 the recommendation also relies on the fact that viral respiratory tract infections (eg, sars) spread by large (10 mm in diameter) respiratory droplets. 22 there is a clear seasonal disease activity because the zarqa, jordan, outbreak was in in april 2012, the al-hasa outbreak was in april-may 2013, and the jeddah and united arab emirates outbreak was in april-may 2014 (fig 1) . therefore, exposure of hcws is more likely during these months because of increased community cases. 23, 24 airborne infection isolation (aii) precautions should be applied during any aerosol-generating procedures as recommended by the who. 21, 25 during the sars outbreak, aerosol-generating procedures associated with increased risk of transmission of sars were intubation, tracheotomy, and manual ventilation. 26 indeed, in the only study addressing the risk of mers-cov transmission among hcws, the reported staff were involved in at least 1 of the following highrisk procedures: intubation, airway suctioning, and sputum induction. 27 the centers for disease control and prevention in the united states and european centre for disease prevention and control continue to recommend the application of aii precautions when caring for patients with mers-cov. 28 these recommendations and the recommendations from other experts rely on the fear of the disease and high case fatality rate. 29 in a recently published debate, the presented evidence supported the use of droplet precautions, not aerosol-generating procedures. 29 a recent study showed that mers-cov rna was isolated from the barn of camels linked to a human mers-cov case suggesting possible aerosolization of mers-cov. 30 the study had several limitations, including the following: it was only 1 positive sample; there was a lack of internationally acceptable sampling strategies of the air, and the sequences are all 100% identical to all other sequences from the patient, camel, and laboratory, which suggests contamination; there was a lack of proof of the causation of aerosol dissemination of the virus; and finally, the viral load in the air sample was higher than the viral load in the camel's nose. 30 in addition, there are no established methods for sampling airborne exposures. 31 for the transmission of sars, and this is likely true with mers-cov, multiple factors play a role in the propagation of infection in a health care setting. these factors include the following: lax basic infection control procedures, aerosol-generating procedures, improper use of personal protective equipment, and mouth exposure to patients' body fluids and excretions. [32] [33] [34] [35] [36] [37] [38] teasing out the most important factors contributing to hcw infection of sars, mers-cov, or emerging respiratory viruses is of paramount importance. in addition, the utilization of maximum respiratory protection is easily applied when there are a few cases, but this strategy puts a burden on any health care system when the number of cases increases substantially. when resources are available, using aii precautions in conjunction with contact precautions would provide the best protection for hcws. isolation of a novel coronavirus from a man with pneumonia insaudi arabia hospital outbreak of middle east respiratory syndrome coronavirus global alert and response (gar): middle east respiratory syndrome coronavirus (mers-cov) e update world health organization. global alert and response (gar): coronavirus infections european centre for disease prevention and control. epidemiological update middle east respiratory syndrome coronavirus (mers-cov) middle east respiratory syndrome coronavirus (mers-cov) summary and literature updateeas of 9 screening for middle east respiratory syndrome coronavirus infection in hospital patients and their healthcare worker and family contacts: a prospective descriptive study assessment of potential risk factors of infection of middle east respiratory syndrome coronavirus (mers-cov) among health care personnel in a health care setting global alert and response (gar): infection prevention and control of epidemic-and pandemic-prone acute respiratory infections in health care epidemiological, demographic, and clinical characteristics of 47 cases of middle east respiratory syndrome coronavirus disease from saudi arabia: a descriptive study middle east respiratory syndrome coronavirus: a case-control study of hospitalized patients clinical features and virological analysis of a case of middle east respiratory syndrome coronavirus infection stability of middle east respiratory syndrome coronavirus (mers-cov) under different environmental conditions infection prevention and control measures for acute respiratory infections in healthcare settings: an update identification of a novel coronavirus in patients with severe acute respiratory syndrome severe acute respiratory syndrome the severe acute respiratory syndrome world health organization. who concludes mers-cov mission in saudi arabia sars: experience at prince of wales hospital, hong kong detection of airborne severe acute respiratory syndrome (sars) coronavirus and environmental contamination in sars outbreak units hospital-associated middle east respiratory syndrome coronavirus infections infection control and mers-cov in health-care workers travel implications of emerging coronaviruses: sars and mers-cov coronaviruses: severe acute respiratory syndrome coronavirus and middle east respiratory syndrome coronavirus in travelers global alert and response (gar): middle east respiratory syndrome coronavirus (mers-cov) e update aerosol generating procedures and risk of transmission of acute respiratory infections to healthcare workers: a systematic review middle east respiratory syndrome coronavirus infections in health care workers european centre for disease prevention and control. epidemiological update: middle east respiratory syndrome coronavirus (mers-cov) debate on mers-cov respiratory precautions: surgical mask or n95 respirators detection of the middle east respiratory syndrome coronavirus genome in an air sample originating from a camel barn owned by an infected patient commentary: protecting health workers from airborne mers-covdlearning from sars which preventive measures might protect health care workers from sars? clinical management and infection control of sars: lessons learned cluster of cases of severe acute respiratory syndrome among toronto healthcare workers after implementation of infection control precautions: a case series transmission of severe acute respiratory syndrome during intubation and mechanical ventilation illness in intensive care staff after brief exposure to severe acute respiratory syndrome sars transmission among hospital workers in hong kong risk factors for sars transmission from patients requiring intubation: a multicenter investigation in toronto key: cord-257595-l8bsoqbx authors: whittemore, paul b. title: covid-19 fatalities, latitude, sunlight, and vitamin d date: 2020-06-26 journal: am j infect control doi: 10.1016/j.ajic.2020.06.193 sha: doc_id: 257595 cord_uid: l8bsoqbx background: since vitamin d is known to be vital in regulating the immune system, and sunlight uv radiation exposure on the skin produces vitamin d and uv intensity is highest nearest the equator, a study was done to examine the correlation between the latitude and covid-19 fatality rates for countries. methods: eighty-eight countries were selected based on their likelihood of providing reliable data. using death rates/million for each country from the “worldometer” web site, a correlation analysis was done between death rates and a country's latitude. results: a highly significant, positive correlation was found between lower death rates and a country's proximity to the equator (pearson r = .40 p<.0001, two-tailed t-test). the r squared of .16 means that 16% of the variation in death rates among nations is accounted for by the latitude of the country. evidence is presented suggesting a direct correlation between sunlight exposure and reduced mortality. discussion: this study is the first to document a statistically significant correlation between a country's latitude and its covid-19 mortality and is consistent with other research regarding latitude, vitamin d deficiency, and covid-19 fatalities. limitations of this study are noted. conclusion: further research is needed to confirm the correlation between latitude and covid-19 fatalities, and to determine the optimum amounts of safe sunlight exposure and/or vitamin d oral supplementation to reduce covid-19 fatalities in populations that are at high risk for vitamin d deficiency. this study is the first to document a statistically significant correlation between a country's latitude and its covid-19 mortality and is consistent with other research regarding latitude, vitamin d deficiency, and covid-19 fatalities. limitations of this study are noted. conclusion: further research is needed to confirm the correlation between latitude and covid-19 fatalities, and to determine the optimum amounts of safe sunlight exposure and/or vitamin d oral supplementation to reduce covid-19 fatalities in populations that are at high risk for vitamin d deficiency. as the covid-19 pandemic spread, death rates reported for over 200 countries and territories on the "worldometer" website appeared to be higher in countries farther from the equator compared with those closer to the equator [1] . a striking example of this appeared in the may 11, 2020 data between ireland and singapore, whose population size was similar (4.9 million vs. 5.3 million respectively), total number of cases were similar (23,135 vs. 23,822 respectively), and number of cases per million of their population was similar (4,685/million vs 4,072/million respectively). however, the number of deaths in ireland was 297/million compared with 4/million in singapore [1] . despite similar numbers of cases, ireland had 74 times more fatalities than singapore. by the second week of may, 2020 several medical studies appeared describing significant correlations between vitamin d insufficiency, covid-19 mortality rates, and the suspected pathophysiology of covid-19 deaths [2] [3] [4] [5] [6] . without adequate vitamin d levels, the lungs are vulnerable to fatal immune system dysregulation including but not limited to cytokine storms, insufficient protection from epithelial cell apoptosis, and deficient epithelial cell repair [4, 6] . because direct sunlight on the skin produces vitamin d in the human body, it has been hypothesized that populations with more regular exposure to natural uv radiation from the sun might have less vitamin d deficiency than those with less uv exposure and consequently lower fatality rates from covid-19 [5] . while uv exposure from sunlight is affected by many factors such as clouds, weather, and pollution, a country's proximity to the equator also affects uv exposure because the intensity of uv radiation is higher closer to the equator. the present study was undertaken to examine the correlation between proximity to the equator and death rates from covid-19. because of the positive correlation between sunlight uv radiation and healthy vitamin d levels in the body, and reported positive correlation between vitamin d deficiency and fatality rates to covid-19, the present study examined the relationship between a country's proximity to the equator and its death rates from the current pandemic. this study hypothesized that countries closer to the equator would have lower fatality rates from covid-19 than countries farther away. to test this hypothesis, a correlation analysis was done comparing a country's latitude and its covid-19 identified death rates per million members of the country's population. to improve the accuracy of reported death between countries, the present study sought to include only countries whose governments have a favorable history of transparency. "transparency international" ranks a total of 180 countries listed from most to least transparent based on multiple measures of government transparency [7] . only the 90 countries in the top 50% were selected for inclusion in this study. latitude data were provided by csgnetwork.com [8] using each country's capital, with exceptions made for china and italy whose vast majority of cases were concentrated in latitudes different from their capitals. wuhan's latitude was used instead of beijing for china, and milan's was used instead of rome for italy. death rates per million in the population for each country was taken from the "worldometer" website on may 17, 2020 [1] . all but 2 of the chosen 90 countries and territories (vanuatu and solomon islands) had data on the worldometer, leaving an n = 88 used for the analysis. the deaths per million/population and latitude for each of the 88 countries were independently entered twice on separate occasions and compared to insure accuracy. a pearson r correlation computation was done on both data sets on google sheets "correlation" and compared for accuracy and consistency [9] . the pearson product-moment correlation on both data sets obtained a correlation coefficient of r = .40. the probability for this outcome was statistically calculated and was found to be extremely low, p<.00005 for one-tailed probability using the hypothesis of lower mortality in populations closer to the equator. the probability of this outcome occurring with no predicted direction was still very low, at p<.0001 for two-tailed probability [10]. the r = .40 translates to a coefficient of determination (r squared) = .16; i.e. 16% of the variance in mortality rates is attributed to the country's latitude. such a high correlation for such a crude factor as latitude is surprising yet credible considering other research showing significant correlations between sunlight exposure and cancers. lower risks for cancer have been found in countries with higher levels of sunlight exposure [11] [12] [13] . one study compared cancers in sunny countries with lower latitudes with less sunny countries with higher latitudes and concluded "that vitamin d production in the skin decreased the risk of several solid cancers (especially stomach, colorectal, liver and gallbladder, pancreas, lung, female breast, prostate, bladder and kidney cancers)" [13] . significantly lower rates of prostate cancer was found in men whose birth place and longest place of residence was in southern states of the us, leading the authors to conclude that "residential sunlight exposure reduces the risk of prostate cancer" [14] . deaths from prostate cancer in america were compared with sunlight uvb exposure and the results were highly significant (r = -.0001), meaning that men who received more sunlight were less likely to die from prostate cancer [12] . the present study finding a strong correlation between latitude and covid-19 fatalities may be explained by the role of sunlight on the skin producing vitamin d [5] , and the research linking vitamin d deficiency and covid-19 fatalities [2] [3] [4] [5] [6] . while the present study does not address vitamin d directly, its production in the human body due to uv sunlight exposure, and the known increase of uv radiation intensity closer to the equator lead to the likelihood that populations closer to the equator have more adequate endogenous vitamin d compared with populations farther away, thereby reducing the likelihood of a fatal dysfunction of the immune system in the presence of covid-19 [11] . the relevance of sunlight exposure for covid-19 is illustrated by comparing statistics involving milan and naples, italy. it is claimed that little or no sunlight uv radiation reaches the earth during winter months in countries whose latitude is above 40 degrees [5] . milan's latitude is significantly above 40 degrees (45.46n) and its covid-19 epidemic accelerated rapidly in the winter month of february , which is nearly two more months of sunshine each year for its population. this comparison supports the hypothesis that the underlying mechanism behind the latitude-mortality correlation is due to differences in sunlight uv radiation and the subsequent levels of endogenous vitamin d in the respective populations. limited sunlight exposure for those in institutional settings, such as prisons and skilled nursing facilities, has been suggested as the reason that 75% of these populations are vitamin d deficient and suffer disproportionately high levels of covid-19 mortality [2] . lower vitamin d levels also are associated with advanced age [18] , diabetes [19] , and hypertension [20] , three of the same risk factors associated with covid-19 fatalities and also common in nursing home populations. even if patients in nursing homes are ingesting adequate amounts of vitamin d in their diet, that may not be sufficient since some studies finds dietary vitamin d less effective than that produced by exposure to sunlight [14] . the current study is the first to document a statistically significant correlation between a country's latitude and its covid-19 mortality. the highly significant probability (p<.0005) that countries proximal to the equator have lower covid-19 fatalities than distal countries supports a probable connection between latitude, sunlight exposure, vitamin d, and covid-19 fatality. the most probable explanation for the correlation found between latitude and covid-19 deaths is the mechanism of vitamin d induced by sunlight exposure [5] . further research is needed to see if endogenous vitamin d is protective against covid-19, and if so, what the optimal amount of safe sunlight exposure is to produce a protective effect. it is important to note that sunlight exposure does not bestow uniform benefits to all members of the population. the effectiveness by which uv radiation on the skin produces endogenous vitamin d is modified by the age, skin color, and sex of the person [3, 5] . the body's efficiency in producing vitamin d from sunlight decreases with age, such that elderly women in ecuador where sunlight is abundant have been found deficient in vitamin d [5] . darker skin color reduces the production of vitamin d from uv exposure, and this may be one of the reasons that african americans suffer twice the prevalence of vitamin d insufficiency compared with the general population (82.1% vs 41.6%) and disproportionately high mortality rates from covid-19 [3] . in addition to skin color and aging, local customs may also impact the results of uv exposure in the population: vitamin d deficiency has been found in girls and women in the middle east despite plenty of sunlight [5] . an important limitation in this study is the unknown duration of time between the identification of first cases in a country and the reported death rates. all other factors being equal, death rates in a country where cases began to appear recently will appear lower than those in countries fighting the virus for a longer time. such variability could raise or lower the numbers used in a correlation study depending on the country's latitude. that does not appear to have changed the striking difference between the death rates in ireland and singapore mentioned in the introduction. on may 11, 2020 the "worldometer" ireland appears to have slowed the rate of increased cases compared with singapore, it now has a fatality rate that is 86 times higher than singapore's. this paired comparison is not only consistent with a positive correlation between equatorial proximity and low fatality rates, it also shows that the difference in the reported death rates for this pair of countries is not the result of different time durations from diagnosis to mortality. the above comparison may be an anomaly, and the fact remains that the unknown duration of time in our 88 countries from first identified cases to reported deaths represents a potential confound to these results. statistical probability testing cannot eliminate this confounder, but may reduce the likelihood of falsely claiming a significant correlation. the more extreme the "p" value is, the lower the likelihood is of erroneously finding a correlation that is not there (i.e. of making a "type 1 error" in statistical hypothesis testing.) the results of this study support that of other research that points to the urgent need to correct vitamin d deficiency to reduce covid-19 fatalities [2] [3] [4] [5] [6] 14] . further research regarding the amounts of safe sunlight exposure and of vitamin d oral supplementation is indicated because, even if they are only partially effective, they are cheap, safe, and readily available. finding such ways for the general public to fortify the immune system (while scientists continue searching for medical treatments and a vaccine) would be a welcome and overdue addition of "inner" strategies in fighting covid-19 to the "outer" ones (social distance, masks, disinfecting surfaces) that have been receiving exclusive attention. worldometer covid-19 coronavirus pandemic the role of vitamin d in the prevention of infection and mortality vitamin d insufficiency is prevalent in severe covid-19 the possible role of vitamin d in suppressing cytokine storm and associated mortality in covid-19 patients does vitamin d status impact mortality from sars-cov-2 infection? med drug discov vitamin d attenuates lung injury via stimulating epithelial repair, reducing epithelial cell apoptosis and inhibits tgf-β induced epithelial to mesenchymal transition corruption perceptions index pearson r computation with "correlation vitamin d and prostate cancer risk: a review of the epidemiological literature geographic patterns of prostate cancer mortality. evidence for a protective effect of ultraviolet radiation does solar exposure, as indicated by the non-melanoma skin cancers, protect from solid cancers: vitamin d as a possible explanation residential sunlight exposure is associated with a decreased risk of prostate cancer annual sunshine and daylight hours in milan differences in vitamin d status between countries in young adults and the elderly the prevalence of hypovitaminosis d and secondary hyperparathyroidism in obese black americans evidence for alteration of the vitamin d-endocrine system in obese subjects the author would like to thank the anonymous reviewers for their informed and valuable suggestions for improving the manuscript. thanks also go to jane l.whittemore and rolly d. spradling, ph.d. for their support and assistance during research and preparation of the manuscript. key: cord-295733-f3rt1fyk authors: ge, tianxiang; lu, ye; zheng, shufa; zhuo, lixin; yu, ling; ni, zuowei; zhou, yanan; ni, lingmei; qu, tingting; zhong, zifeng title: evaluation of disinfection procedures in a designated hospital for covid-19 date: 2020-08-22 journal: am j infect control doi: 10.1016/j.ajic.2020.08.028 sha: doc_id: 295733 cord_uid: f3rt1fyk background: coronavirus disease 2019 (covid-19) has spread globally and been a public health emergency worldwide. it is important to reduce the risk of healthcare associated infections among the healthcare workers and patients. this study aimed to investigate the contamination of environment in isolation wards and sewage, and assess the quality of routine disinfection procedures in our hospital. methods: routine disinfection procedures were performed three-times a day in general isolation wards and six-times a day in isolated icu wards in our hospital. environmental surface samples and sewage samples were collected for viral rna detection. sars-cov-2 rna detection were performed with quantitative reverse transcription pcr (qrt-pcr). results: a total of 163 samples were collected from february 6th to april 4th. among 122 surface samples, two were positive for sars-cov-2 rna detection. one was collected from the flush button of the toilet bowl, and the other was collected from a hand-basin. although 10 of the sewage samples were positive for viral rna detection, all positive samples were negative for viral culture. conclusion: these results revealed the routine disinfection procedures in our hospital were effective in reducing the potential risk of healthcare associated infection. two surface samples were positive for viral detection, suggesting that more attention should be paid when disinfecting places easy to be ignored. coronavirus disease 2019 (covid-19), which is caused by severe acute respiratory syndrome coronavirus 2 (sars-cov-2), has globally spread and been declared as a pandemic by the world health organization (who) on march 11 th , 2020 [1] . covid-19 has been spreading fast because people are generally susceptible. the common symptoms of covid-19 patients include fever, fatigue, dry cough, and the computed tomography scans showed bilateral patchy shadows or ground glass opacity in the lungs, while headache, dizziness, and gastrointestinal symptoms including abdominal pain, diarrhea, and vomiting are less common symptoms [2] . the predicted incubation time of sars-cov-2 is 14 days, which may lead to a high rate of asymptomatic and subclinical infection among susceptible individuals, and people may get infected and be unaware of how or where it came from [3] . thus, effective interventions should be taken to break the chain of transmission of sars-cov-2. both confirmed patients and suspected individuals have potential to transmit the virus, since the viral shedding of asymptomatic patients have already been confirmed [4, 5] . the transmission of the virus is mainly by the respiratory droplets or by direct and indirect contact, and the viable sars-cov-2 particles could be detected for more than 1.5~3 hours in aerosols under experimental conditions [6, 7] . the droplets produced when covid-19 patients coughed or sneezed could be transported over a long distance by airflow before settled on the surface, and the sars-cov-2 could stay viable for a long time after the droplets completely evaporated [8, 9] . the rna purification is the gold standard for the detection of sars-cov-2 in samples, and the existence of sars-cov-2 rna in the specimens of respiratory tract and feces of confirmed and asymptomatic patients have been confirmed by several researches [10, 11] . therefore, the environmental contamination could be attributable to direct contact with infected respiratory fluids, feces and depositing of aerosol particles [12] . these results also indicate that sewage of the hospital could also be contaminated by covid-19 patients' bodily fluids. many researches have reported the contamination of air and surfaces by sars-cov-2, emphasizing the importance of cleaning and disinfection in hospitals, despite the viability of the virus still need to be investigated [12] [13] [14] [15] . due to lack of personal protective equipment (ppe), a lot of healthcare workers (hcws) became infected during period of covid-19 patients' care at the early stage of this pandemic [16] . thus, disinfection procedures are highlighted in mitigating healthcare associated infections (hais). in this study, we enlarged the sample size and enhanced the sampling frequency to evaluate the quality of routine disinfection in isolation wards and sewage. in order to identify potential risk factors, places easy to be ignored were also sampled after disinfection, such as door handles, flush button of the toilet bowl and hand-basin. this study was conducted in zhijiang campus, the first affiliated hospital of zhejiang university, china. the hospital was originally a grade 3a hospital and became one of designated hospitals for covid-19 patients in zhejiang province since the outbreak of covid-19. the isolation wards were separated into three parts and two passages, including a contaminated area, a semi-contaminated area, and a clean area. one passage was for patients, and the other was for medical stuff. the arrangement of the isolation wards was described in detail in the article we published before [17] . and the preprocessing disinfection equipment (tianxingjian water-treatment co., ltd., zhejiang, china) were added into the sewage disinfection system of the hospital. when compared with previous study, more places that could be potentially contaminated by covid-19 patients were sampled for viral rna detection, such as the flush button of the toilet bowl, medical refuse transfer trolley, elevators, and the examination rooms for these patients. both respiratory and feces samples were collected during the hospitalization of covid-19 patients and after their discharge to evaluate the quality of our disinfection procedures. patients with covid-19 were confirmed by the positive polymerase chain reaction (pcr) results of respiratory samples. both respiratory samples and feces samples were collected for pcr test during their hospitalization. suspected individuals were hospitalized in single-person rooms with dedicated toilets. confirmed patients were hospitalized into cohort-rooms with shared toilets in general isolation wards or isolation intensive care unit (icu) wards based on severity of illness. in a cohort-room, beds were spaced at least 1.2 meters apart, and up to three patients could be hospitalized in at a time ( figure 1 ). routine disinfection procedures were performed three-times a day in general isolation wards and six-times a day in isolated icu wards. the environmental surface sampling was conducted in isolation wards where confirmed patients were hospitalized in. we collected samples from high-touch surfaces of the contaminated area, the semi-contaminated area and the clean area in both general isolation wards and isolation icu wards, including beeper, flush button, hand-basin, door handle, bedside table, medical surface, elevator button, desktop, computer mouse and keyboard, telephone and others. these samples were collected two hours after the routine cleaning and disinfection. we also collected samples from medical equipment and other high-touch surfaces in examination rooms for covid-19 patients after terminal disinfection procedures. classiqswabs (copan flock technologies, brescia, italy) were used for environmental surfaces sampling, and universal transport medium were used for sample transportation and storage before performing the pcr tests. sewage from the preprocessing disinfection equipment and the final disinfection pool were collected for viral rna detection. briefly, 1ml sewage sample was centrifuged (12000×g for 5 mins at 4 ℃) to remove the solids, and 300 μl supernatant was collected for rna extraction and pcr assay. of the paired sewage samples collected from the preprocessing disinfection equipment, six (6/14) from the inlets and four (4/14) from the outlets were found to be positive for sars-cov-2 rna testing ( table 2 ). the viral culture of these samples was negative. all samples collected from the final disinfection pool were negative for sars-cov-2 rna testing. all samples collected from the examination rooms after the terminal disinfection were negative for sars-cov-2 rna testing (table 3 ). it was reported that the covid-19 has caused more than 82,341 infections across china, over 3000 of which were in hcws by april 15, 2020 [16] . most of the infected hcws were confirmed at the early stage of this pandemic, when environmental cleaning and disinfection protocols were not established and hcws were not aware of the potential risk of getting infected [18] . a research of the stability of sars-cov-2 indicated that the virus could be detected in 4 hours on copper and 24 hours on cardboard, while it could be detected up to 72 hours after application to plastic and stainless steel [7] . despite of the human-to-human transmission, the contact of contaminated surfaces may contribute to the hais among the hcws and patients [14] . therefore, the environmental cleaning and disinfection protocols were extremely important in preventing the hais. all covid-19 patients and suspected individuals without mechanical ventilation were wearing surgical masks during their hospitalization in our hospital. and alcohol-based hand hygiene sanitizer dispensers were placed nearby the beds in the patient's room. since the environment could become contaminated with the virus, touching infected patients or patient surroundings could be a possible route for sars-cov-2 transmission, which would eventually cause the hais among patients and hcws. it was important to perform the hand hygiene to stop the spread of the virus from one place to another. in our hospital, ppe was used by hcws in isolation wards, including n95 masks, gloves and disposable isolation gowns. the ppe was removed in the removal area, thus hcws were required to perform hand hygiene without removing gloves in isolation wards. the key moments and procedures for hand hygiene were in accordance with the who guidelines [19] . combined with routine disinfection, these procedures were proved to be effective according to the as the epidemic had been brought under control in china, few new cases were found in zhejiang province, and patients with covid-19 were recovered and discharged from our hospital. terminal disinfection and environmental sampling was required for the isolation wards and examination rooms in order to provide medical services for non-covid-19 patients. the disinfection procedures for examination rooms were consistent with the procedures for the isolation wards. these areas could not be used for non-covid-19 patients until all the environmental samples collected were negative for sars-cov-2 rna detection. in this study, surface samples collected from the examination rooms were all negative for sars-cov-2 rna detection, and the samples collected from isolation wards and other places were also negative for viral rna detection, which indicated that the terminal disinfection was effective. the presence of sars-cov-2 rna in feces of covid-19 patients had been widely reported [20] [21] [22] , which meant the virus could also be detected in the sewage. it had been verified by some researches about the wastewater in usa, france, italy and china [17, [23] [24] [25] . individuals could get infected with sewage which contained the sars-cov-2 virus via the fecal-oral route, in spite of the viability of sars-cov-2 virus in sewage was still unknown [26] . to our knowledge, few studies have provided insights into whether the contaminated sewage could cause covid-19 [27] . in order to sufficient inactivate sars-cov-2 virus in the sewage drained into urban sewage, the preprocessing disinfection equipment were added into the sewage disinfection system of the hospital. although some sewage samples collected from the inlets and outlets were positive, the results of viral culture for these samples were all negative. this result indicated there was no viable virus due to disinfection in the preprocessing disinfection equipment. and all samples from the final disinfection pool were negative. these results indicated the disinfection of patients' feces was necessary to reduce the potential risk of sars-cov-2 transmission. our study had several limitations. first, we did not collect the air samples due to the lack of air sampling machine. other researches had revealed the presence of sars-cov-2 rna in aerosol, which indicated the air could be contaminated by the virus, and patients could be infected in the isolation wards [12, 28] . second, the positive samples of surfaces were determined by pcr tests, while the ability of virus could not be determined. third, we collected the samples at single time point in the disease process of individual patients, and did not investigate whether there is any relationship between the levels of environmental contamination and the disease. in conclusion, during the covid-19 pandemic, our hospital implemented a set of disinfection procedures to reduce the potential risk of hais via the directly contact of contaminated surfaces. the environmental surveillance of sars-cov-2 in this study revealed our routine disinfection procedures were effective, despite two samples tested positive for sars-cov-2 rna. no hai of covid-19 were detected in our hospital. additionally, the disinfection of patients' feces was sufficient for the inactivation of sars-cov-2 in the sewage drained from the hospital. these findings indicated the disinfection procedures performed in our hospital were effective in preventing the hcws from getting infected. further studies with larger sampling size were required to clarify the relationship between the levels of contamination and the disease. who director-general's opening remarks at the media briefing on covid-19 -11 hospitalized patients with 2019 novel coronavirus-infected pneumonia in wuhan does sars-cov-2 has a longer incubation period than sars and mers temporal dynamics in viral shedding and transmissibility of covid-19 presumed asymptomatic carrier transmission of covid-19 experimental aerosol survival of sars-cov-2 in artificial saliva and tissue culture media at medium and high humidity aerosol and surface stability of sars-cov-2 as compared with sars-cov-1 aerosol transmission of infectious disease coughs and sneezes: their role in transmission of respiratory viral infections, including sars-cov-2 laboratory management for sars-cov-2 detection: a user-friendly combination of the heat treatment approach and rt-real-time pcr testing epidemiologic features and clinical course of patients infected with sars-cov-2 in singapore detection of air and surface contamination by sars-cov-2 in hospital rooms of infected patients asymptomatic covid-19 patients can contaminate their surroundings: an environment sampling study environmental contamination of sars-cov-2 in healthcare premises severe acute respiratory syndrome coronavirus 2 rna contamination of inanimate surfaces and virus viability in a health care emergency unit avoiding hospital-related infections during the covid-19 epidemic sars-cov-2 rna detection of hospital isolation wards hygiene monitoring during the coronavirus disease 2019 outbreak in a chinese hospital analysis of the infection status of the health care workers in wuhan during the covid-19 outbreak: a cross-sectional study the presence of sars-cov-2 rna in the feces of covid-19 patients evaluation of sars-cov-2 rna shedding in clinical specimens and clinical characteristics of 10 patients with covid-19 in macau clinical and virological data of the first cases of covid-19 in europe: a case series sars-cov-2 titers in wastewater are higher than expected from clinically confirmed cases evaluation of lockdown impact on sars-cov-2 dynamics through viral genome quantification in paris wastewaters first detection of sars-cov-2 in untreated wastewaters in italy wastewater-based epidemiology: global collaborative to maximize contributions in the fight against covid-19 coronaviruses in wastewater processes: source, fate and potential risks aerodynamic analysis of sars-cov-2 in two wuhan hospitals key: cord-034660-g28qmyh8 authors: sciamanna, christopher; du, ping; cialdini, robert title: using persuasion science to improve covid-19 contact tracing date: 2020-11-05 journal: am j infect control doi: 10.1016/j.ajic.2020.11.004 sha: doc_id: 34660 cord_uid: g28qmyh8 nan in the battle against the spread of covid-19, contract tracing is widely seen as a crucial requirement (www.preventepidemics.org) to reopen society. since its first call with a covid-19 patient ("case") on march 27, the contact tracing program at penn state health, previously described in this journal 1 , has completed calls with 87% of all cases. in the past few weeks, as the performance of other programs has been reported, it appears that our contact tracers are unusually successful. in neighboring lancaster county, with demographics similar to ours, calls with only 48% of cases are being completed 2 . in massachusetts, which has one of the country's most established tracing programs, only 60% of attempted calls are answered 3 . in new york city, only 42% of people with covid-19 gave information about close contacts to tracers 3 , whereas penn state health's success rate in this regard is 62.5% since its inception. while we recognize there may be other factors that can impact these rates, such as racial, ethic, and other demographic differences in the callers and call recipients, we believe that part of performance difference stems from the scripting tactics we have used. we based our calling script on evidence from randomized trials in the fields of behavioral economics and persuasion science. we present them here for use by others as we are concerned that, as contact tracing is scaled nationwide, it may be significantly less effective than it could otherwise be. below, we highlight in italics how our script differs from one suggested for use nationally by the association of state and territorial health officials (astho), and briefly explain how incorporating each persuasion-relevant tactic may explain the difference in performance. hello, my name is _______ and i'm calling from _______. i am calling today because we are closely monitoring the outbreak of respiratory illness caused by the new coronavirus (called covid-19). we have identified you as potentially being sick. can you first please confirm the following information? [confirm name matches] thank you. can you please assist in providing some additional information so that we may understand your risk and potentially enroll you in public health monitoring? i am going to ask you to think back over each day while you have been sick to remember what you did each day. this will help us figure out who you may have been around, and who else might get sick. if you are having a hard time remembering, sometimes it is helpful to look back at a calendar, or on your phone for messages sent on each day, or even at your credit card receipts. hi, this is _____ calling from penn state health (designed to incorporate the tactics of conveying expertise and trustworthiness of a health care provider and university, on the one hand, which increases a communicator's influence and enhancing feelings of unity of place, on the other, which increases survey participation 4 ). i'm not sure if you've been told before but unfortunately, the results of your covid or coronavirus test were positive, meaning that you were infected with the virus at some point. can i ask, how are you doing? how are you holding out in this crisis? (designed to incorporate the tactic of enhancing rapport, which increases compliance with medical professionals requests 5 ). i'm not sure if someone told you that other people will be calling, but i work with infection control and my team's job is to talk to people who have been diagnosed with covid and find out all of the people who they have been in contact with, so we can get those people to quarantine themselves. this is not mandated by law, so you are free not to be involved in this (designed to incorporate the tactic of reducing perceived threats to personal autonomy that, using similar wording, doubled request compliance over 32 studies 6 ) , but this process is very important to help us stop the disease from spreading and has been used to stop many outbreaks in the past (designed to incorporate the tactic of demonstrating social proof, in which people follow the lead of multiple successful others 7 ). this process is one of the only things we can do to stop the spread of this virus, so your help is essential. most importantly, your privacy is our high priority and your information is completely confidential. if you agree to help, we will reach out to people and places you've been in contact with and just tell them that they have been exposed to someone without telling them who. most people contact many people each day so it's very unlikely they'll identify you (designed to incorporate the tactic of reducing privacy concerns which, if not addressed, appear to undercut compliance with contact tracing 3 ). if you agree to help, we will reach out to the people and places you've been in contact with to tell them they were exposed and help them get testing and a doctor's note, if needed. we would also like to talk to you about your own quarantining measures and ways that we may be able to help (designed to incorporate the tactic of reciprocity, in which people feel obligated to help to those who seek to help them and their close others 8 ). do you have any questions so far? ok, the next step is for us to talk about the people and places you may have been in contact with. i know the questions will feel invasive, like a police investigation. but this detective work is essential for doing all we can to stop the spread of this virus, so i really appreciate your help (designed to incorporate the tactic of enhancing source credibility, in which a communicator points to a drawback before advancing to a request 9 ) . is that okay with you? we fully recognize that we have not tested our scripting, in a randomized controlled trial, against the astho script or any other script, so it is possible that our script is not actually superior. however, the astho script includes only information, though decades of behavioral economics and persuasion science research suggest that specific additions to an information-only script can markedly improve performance. these behavioral strategies are summarized in a recent report, co-authored by dr. cialdini, published by the societal experts action network (sean), an activity of the national academies of sciences, engineering, and medicine, entitled "encouraging adoption of protective behaviors to mitigate the spread of covid-19: strategies for behavior change (2020)" 10 . given how simple these changes are to make and the strength of the underlying science, incorporating these tactics into existing scripts, or formally testing these and similarly proven scripting tactics, should be given serious consideration. we present this in the spirit of quality improvement. the institute of medicine's crossing the quality chasm noted that it takes 17 years, on average, for new knowledge generated by randomized controlled trials to be incorporated into practice 11 . given the urgency of limiting morbidity and mortality from covid-19 while simultaneously re-opening society, along with the widely agreed impact that contact tracing may have, we are hopeful that these scientifically-grounded insights can be implemented much more quickly. implementation and process of a covid-19 contact tracing initiative: leveraging health professional students to extend the workforce during a pandemic only half of people identified for covid-19 exposure in lancaster county may be isolating hired 3,000 workers for contact tracing. it's off to a slow start an experimental test of the effects of survey sponsorship on internet and mail survey response physician communication and patient adherence to treatment: a meta-analysis but you are free" compliance-gaining technique reappraising academic and social adversity improves middle school students' academic achievement, behavior, and well-being reciprocity and the art of behavioural public policy accentuate the negative: the positive effects of negative acknowledgment national academies of sciences, engineering, and medicine; 2020. 11. crossing the quality chasm : a new health system for the 21st century key: cord-264972-hrbo3awj authors: yee, colin; suarthana, eva; dendukuri, nandini; nicolau, ioana; semret, makeda; frenette, charles title: evaluating the impact of the multiplex respiratory virus panel polymerase chain reaction test on the clinical management of suspected respiratory viral infections in adult patients in a hospital setting date: 2016-11-01 journal: am j infect control doi: 10.1016/j.ajic.2016.04.221 sha: doc_id: 264972 cord_uid: hrbo3awj a retrospective cohort design was used to study the impact of a multiplex respiratory virus panel polymerase chain reaction test in 186 adult patients with suspected influenza-like illness. decisions regarding continuation of empirical antiviral therapy appear to be impacted by the test. however, the impact on reducing antibiotic use remains unclear. respiratory tract infections are very common and manifest themselves through a wide range of symptoms. 1, 2 it is often difficult to distinguish between viral and bacterial etiologies on clinical grounds alone; however, rapid and accurate etiologic identification is important to guide patient management and hence reduce morbidity and mortality and implement appropriate infection control practices. [3] [4] [5] targeted therapy is expected to decrease the risk of emergence of drug-resistant bacterial strains and of nosocomial infections, such as clostridium difficile. 6 in the context of limited health care resources, there is interest in assessing the impact of respiratory virus diagnostic testing on antimicrobial therapy. nucleic acid amplification testing is now considered the gold standard for respiratory virus testing. 7 an in-house multiplex reverse transcription polymerase chain reaction (mrvp) that simultaneously detects and identifies 12 respiratory virus targets (influenza a, influenza b, parainfluenza 1-2-3, adenovirus, rhinovirus, enterovirus, coronavirus (types 229e and oc43), respiratory syncytial virus, and human metapneumovirus) and has an excellent turnaround time of ≤24 hours has been used since 2009 at the mcgill university health centre. the objective of our study was to evaluate the impact of the mrvp test on the use of antiviral and antimicrobial therapy among adult patients in a hospital setting (either emergency room or inpatients) with suspected influenza-like illness. the study was designed as a retrospective cohort study conducted among adult patients in the emergency department and inpatients during the peak of the 2013-2014 influenza season. similar to many hospital centers in canada, the mcgill university health centre emergency room includes a holding area for internal medicine patients, including sick patients under observation and admitted patients waiting for a bed. length of stay in these patients can average ≥24 hours. polymerase chain reaction testing is indicated for patients likely to be admitted or at risk for complications. the mrvp test is carried out using automated specimen extraction (nuclisens extractor; biomérieux, marcy-l'étoile, france) and simultaneous amplification of 11 respiratory viruses on a lightcycler 480 (roche applied systems, penzberg, upper bavaria, germany). the assay was validated in 2008 and field tested in 2009 8, 9 (see supplementary appendix s1 for details). between january 1 and march 1, 2014, 93 adult patients with suspected influenza-like illness and who tested positive by mrvp (positive for influenza or other respiratory virus) were enrolled (exposed group). for efficiency, of 564 patients (either emergency department patients or inpatients) who had a negative mrvp test during the study period, an equal number of patients (n = 93) were randomly selected within a 1-week time frame of the exposed group. clinical data, including demographic characteristics, comorbidities (present or absent), patient location at the time of mrvp testing, prescription of antibiotics and antivirals, and chest radiograph results, were collected from the medical charts. use of antibiotics considered potentially prescribed for respiratory bacterial infection (namely ceftriaxone, doxycycline, azithromycin, piperacillin-tazobactam, and fluoroquinolones [moxifloxacin]) was recorded. patients were classified according to their mrvp results into 1 of the following 3 groups: influenza positive, noninfluenza positive, and negative to all viruses. we compared clinical characteristics of patients in the 3 groups by calculating the difference in means (for continuous characteristics) or difference in proportions (for categorical characteristics) together with a 95% confidence interval. we evaluated whether the mrvp test result was associated with the changes in management in antiviral and antibiotic treatment (see the definition in supplementary appendix s1), after stratifying by patient location. we also evaluated the association between mrvp and the decision to admit patients from the emergency room setting. all analyses were performed using ibm spss 20 for windows (ibm, armonk, ny). of 186 selected patients, half were men (table 1) . on average, patients in the positive influenza group were younger than the negative influenza group (difference in mean, -11 years; 95% confidence interval, -20 to 1) and the positive noninfluenza group (difference in mean, -7 years; 95% confidence interval, -17 to 5). patients in the 2 test positive groups were more likely to present with fever and cough than those who tested negative. the percentage of patients with a comorbidity was very high in all 3 groups. the percentage of patients suspected to have pneumonia based on chest radiography results was similar in all 3 groups. seventy percent of the patients with positive results and onethird of patients with negative results were only treated in the emergency room, whereas the rest were hospitalized at the time of testing. polymerase chain reaction test results were available on the same day for 80 (43%) of the patients and on the next day for the remaining patients. results were available for all patients in our study prior to their discharge from hospital. among hospitalized patients, 7 of 17 (41.2%) patients positive for influenza were empirically treated with oseltamivir antiviral prior to test result, and all of them continued the treatment given the mrvp test result (table 2) . after a negative mrvp result, empirical oseltamivir antiviral treatment was discontinued in two-thirds (10/ 15) of the hospitalized patients. empirical oseltamivir antiviral treatment was also discontinued in all hospitalized patients with a positive noninfluenza result. the proportions of empirical antibiotic treatment in hospitalized patients were 66.1% in patients with negative mrvp test, 70.0% in patients with positive noninfluenza, and 70.6% in patients with positive influenza. empirical antibiotic treatment was continued in 85.4% of hospitalized patients with negative mrvp test. empirical antibiotic treatment was discontinued in only one-quarter (ie, 3/12) of mrvp-positive hospitalized patients. when further stratifying hospitalized mrvp-positive patients according to whether they had suspected pneumonia, we found that 5 of 6 patients with suspected pneumonia continued empirical antibiotics compared with note. values are n (%) or as otherwise indicated. mrvp, multiplex reverse transcription polymerase chain reaction; n/a, not applicable. *chest radiograph results were missing for 9, 2, and 8 patients in the positive influenza, positive noninfluenza and negative categories, respectively. † results were missing for 8 patients among the influenza-negative category. 4 of 6 patients with no suspected pneumonia. the high prevalence of comorbidity did not permit a stratified analysis. most influenza-positive patients, who were not treated empirically, were highly likely to be initiated after the test results: 80% (8/10) among hospitalized patients and 85% (6/7) among emergency room patients scheduled to be admitted. among patients with a negative mrvp test who were not empirically treated, antibiotic treatment was initiated in only 1 patient in each setting: 1 in 21 (5%) hospitalized patients and 1 in 9 (11%) emergency room patients. among patients tested in the emergency room, 20.6% (7/34) of mrvp-positive patients were admitted compared with 78.9% (15/ 19) of mrvp-negative patients. our findings show that the antiviral management was generally appropriate during influenza season. after the mrvp result, all admitted patients with positive influenza continued empirical oseltamivir antiviral treatment. a high proportion of patients with negative results and all patients with noninfluenza positive result discontinued the treatment. antiviral was initiated in most admitted patients with positive influenza who were not empirically treated. impact of the mrvp test on antibiotic management was less evident. seventy percent of patients in the ward who turned out to have positive influenza were empirically treated with antibiotics, and only a quarter of them discontinued the treatment given the mrvp result. the suspicion of a concomitant presence of a secondary bacterial infection is the most likely explanation for the continuation of antibiotic in these cases. however, the small sample size of this study precluded our ability to study this hypothesis in greater depth. moreover, the introduction, use, and interpretation of this mrvp test is relatively new to our institution, and clinical practice may have not changed yet. nonetheless, a mrvp-positive result in the emergency room setting appears to be associated with discharge from the hospital. our nonrandomized study design has the drawback that the differences in mrvp-positive and mrvp-negative patients may be attributable to the difference in distribution of important confounding factors (eg, age, comorbidity). we could not further analyze the role of comorbidity on the continuous use of antibiotics or antivirals because almost all of the treated patients had a comorbidity. in future studies, a finer definition of comorbidity and suspicion of a bacterial respiratory infection would be needed to investigate the reasons for continuation of antibiotic use. another limitation of this work is that we were not able to measure the impact of the mrvp test on infection control because of the lack of individual-level data on initiation of these measures. we conclude that the mrvp test could potentially positively impact the clinical management of respiratory viral infections in adult patients. however, the impact on reducing antibiotic use remains unclear. our findings support the concept that viral respiratory tract infections are a common cause of inappropriate antibiotic usage and should be targeted for education and antibiotic stewardship programs. epidemiology of viral respiratory infections the epidemiology of respiratory tract infections clinical and financial benefits of rapid detection of respiratory viruses: an outcomes study impact of rapid diagnosis on management of adults hospitalized with influenza effect of rapid diagnosis on management of influenza a infections general principles of antimicrobial therapy detection of respiratory viruses by molecular methods a real-time rt-pcr assay for detection of influenza h1n1 swine-type and other respiratory viruses a multiplex rt-pcr assay for the rapid diagnosis of 10 respiratory viruses we thank ian schiller for his contribution to data management. supplementary data to this article can be found online at doi:10.1016/j.ajic.2016.04.221. key: cord-271187-rlevoj41 authors: vijh, rohit; ghafari, cher; hayden, althea; schwandt, michael; sekirov, inna; morshed, muhammad; levett, paul; krajden, mel; boraston, suni; daly, patricia; lysyshyn, mark; harding, john; mclennan, meghan; chahil, navdeep; mak, annie; mckee, geoff title: serological survey following sars-cov-2 outbreaks at long term care facilities in metro vancouver, british columbia: implications for outbreak management and infection control policies date: 2020-10-18 journal: am j infect control doi: 10.1016/j.ajic.2020.10.009 sha: doc_id: 271187 cord_uid: rlevoj41 a cross-sectional serological survey was carried out in two long term care facilities that experienced covid-19 outbreaks in order to evaluate current clinical covid-19 case definitions. among individuals with a negative or no previous covid-19 diagnostic test, myalgias, headache and loss of appetite were associated with serological reactivity. the us cdc probable case definition was also associated with seropositivity. public health and infection control practitioners should consider these findings for case exclusion in outbreak settings. a cross-sectional serological survey was carried out in two long term care facilities that experienced covid-19 outbreaks in order to evaluate current clinical covid-19 case definitions. among individuals with a negative or no previous covid-19 diagnostic test, myalgias, headache and loss of appetite were associated with serological reactivity. the us cdc probable case definition was also associated with seropositivity. public health and infection control practitioners should consider these findings for case exclusion in outbreak settings. given the high mortality rate associated with covid-19 among ltc residents 1 , timely and evidenceinformed interventions are critical for mitigating transmission risk. serological testing may be useful to evaluate and inform public health infection control practices by uncovering cases missed during an outbreak using current laboratory-based and clinical case definitions. 2 communicable disease case definitions can be utilized in public health for a variety of purposes (ex. surveillance). in the context where diagnostic tests are not rapidly available or have limited sensitivity, symptom-based case definitions are essential. in ltc outbreaks, uncontrolled introduction of infections not identified through testing may perpetuate transmission despite outbreak control measures. currently, various national probable/epidemiologically-linked (clinical) case definitions largely focus on respiratory symptoms (ie. cough and shortness of breath), with varying inclusion of systemic/generalized symptoms (ie. fever, chills, loss of appetite)(appendix a). given ltc residents often present with non-specific generalized symptoms for other respiratory pathogens 3 , potential cases of covid-19 are likely missed and potentially contribute to propagation within ltc facilities. our analysis aims to provide a descriptive overview of a serological survey of ltc residents and staff members following outbreaks at two facilities and evaluate clinical case definitions of covid-19 used in ltc outbreaks against serological results. a cross-sectional serological survey of ltc residents and staff members was administered from venous specimens were tested using an orthogonal approach 4 with five different commerciallyavailable sars-cov-2 antibody assays with varying target immunoglobulin and epitopes (appendix b), in accordance with manufacturers' recommendations. each individual was assigned by a medical microbiologist into "reactive", "non-reactive" or "equivocal" category based on degree of agreement/disagreement of aggregate antibody results from all tests. clinical information (symptomatic/asymptomatic history, symptoms recorded, medical comorbidities, medications) for each individual was gathered by abstracting data from a standardized case report form (appendix c), medical charts of ltc residents, and phone interviews. resident symptoms were documented through a combination of resident report/staff observation and utilization of a standardized symptom checklist(appendix d). symptom onset dates were captured using both clinical information and diagnostic test data (appendix e). participants were classified as immunocompromised or immunocompetent using provincial criteria (appendix f). data on clinical information and diagnostic test results were abstracted from may 22 nd to june 5 th 2020. descriptive statistics of the study population were summarized in r (v.3.6.2) and stata (v.15). multi-variable logistic regression (adjusting for age, gender and facility) was used to generate adjusted odd ratio (aor) estimates of associations between serological results and different individual symptoms, symptom clusters (appendix a), immunocompromise status (yes vs. no) and history of negative naats (<3 vs.3). covariate selection accounted for differences between staff and residents (age, gender) and facility characteristics. individuals for whom we could not access a clinical history were excluded from regression analyses (n=6). research ethics board review was not required, as this study was part of routine public health operations for quality improvement and program evaluation. serological testing was offered to all residents and staff in both facilities, with 44% (303/691) consenting to participate (48% staff, 39% residents). a total of 303 ltc residents (n=127) and staff (n=176) were included in the study. after excluding 12 individuals with equivocal serological results, 39% (n=113) were reactive and 61% (n=178) were non-reactive. table 1 provides a descriptive epidemiological summary of study participants. the median time between symptom onset and serological collection was 50 days (iqr= 15) for the entire cohort, 52 days (iqr= 9.5) for naat positive cases, and 48 days (iqr=23.5) for no or negative naat cases. .60) were most prominently associated with increased odds of reactive serology ( figure 1a ). all symptom cluster case definitions were significantly associated with seropositivity ( figure 1c ). serological studies of covid-19 have largely focused on cluster identification and characterization 9 , assessment of seroprevalence 10 , and patterns of seroconversion 11 . a recent study among hospitalized patients also utilized serology to identify cases with negative naat or asymptomatic infections 12 ; however, no studies to date have used serology to inform clinical case definitions and subsequently infection control measures in ltc facilities. our findings support using a low threshold for symptoms in ltc settings (particularly nonrespiratory symptoms) when considering exclusion and isolation of symptomatic staff and residents. given the non-specific nature of symptoms found to be highly predictive, such as headache, myalgia, and loss of appetite, implementation of universal contact/droplet precautions early in the outbreak may be effective in curbing transmission within facilities, rather than relying on isolating residents when they present with fever and/or respiratory symptoms. moreover, staff and residents with several negative naats for covid-19 should warrant further investigation with serology and/or be considered a clinical case if repeat naat testing is due to persisting symptoms. lastly, ongoing evaluation of the canadian, european, and who probable case definitions in outbreak settings is necessary, given gaps in covid-19 diagnosis highlighted by this and other serological studies. 12 amendment to align more closely with the us cdc definition, which was more sensitive to historical infection in this analysis, may be appropriate in ltc outbreak settings. strengths of this study include serological testing on several platforms and utilization of multiple sources (i.e. phone interviews, medical charts and public health data) to gather reliable clinical histories immediately after the outbreak; however, the study was limited by the small sample size, preventing further regression analysis stratified by case type. given that systematic collection of clinical histories was refined over the duration of the outbreaks, symptoms may have been underreported for some resident cases. our findings should be generalized to other settings with caution, as the study was conducted in an outbreak setting with a high pre-test probability for covid-19. the use of serological testing introduced some additional limitations. baseline serological testing was not available at the start of the outbreaks and thus prior cases may not have been identified; however, both ltcf facilities represent the earliest covid-19 outbreaks and cases in canada, reducing the theoretical probability of prior infection to the start of the outbreak. due to the rapid and evolving nature of the pandemic response, there is also potential risk for misclassification bias, as the clinical and diagnostic laboratory data structures used to compare and interpret serology results underwent continual quality improvement and reconciliation. while diagnostic misclassification may also occur due to the performance characteristics of covid-19 serological assays, tests used in this evaluation were found by the performing laboratory to have specificity of 97%-99.5% and sensitivity of up to 98% at >14 days from symptoms onset. an orthogonal approach to the interpretation of test results further improved the overall specificity. our serological survey demonstrates that generalized/non-specific symptoms and repetitive negative naat testing are highly associated with seropositivity. the findings of this survey can help inform case identification when managing covid-19 outbreaks in ltcfs. impact of covid-19 on residents of canada's long-term care homes -ongoing challenges and policy response. int long term care policy netw the important role of serology for covid-19 control new respiratory viruses and the elderly sars-cov-2 (covid-19) serology: implications for clinical practice, laboratory medicine and public health real-time tracking of self-reported symptoms to predict potential covid-19 clinical features of covid-19 asymptomatic and presymptomatic sars-cov-2 infections in residents of a long-term care skilled nursing facility connecting clusters of covid-19: an epidemiological and serological investigation low sars-cov-2 sero-prevalence based on anonymized residual serosurvey before and after first wave measures in british columbia different longitudinal patterns of nucleic acid and serology testing results based on disease severity of covid-19 patients. emerg microbes infect antibody responses to sars-cov-2 in patients with covid-19 funding statement: no financial sources/grants to disclose. key: cord-009169-hzxgi1t0 authors: sun, bingwei title: nosocomial infection in china: management status and solutions date: 2016-07-01 journal: am j infect control doi: 10.1016/j.ajic.2016.01.039 sha: doc_id: 9169 cord_uid: hzxgi1t0 nan to the editor: in china, nosocomial infection is a prominent public health concern and is associated with an annual direct economic burden of $1.5-$2.3 billion (¥10-¥15 billion). 1 advances in medical technology, extensive application of novel diagnostic and therapeutic techniques, and increased adoption of traumatic and invasive interventions have drastically altered the source, transmission route, and susceptible population of nosocomial infection. emergence of multidrug-resistant bacteria has increased the proportion of refractory infections and the challenges of infection control. [2] [3] [4] china has reinforced legislation to control nosocomial infection, drawing extensive support from society and medical community. 5 this transition is reflected in the chinese governmental response to the epidemic of middle east respiratory syndrome. in january 2013, 99 out of 120 patients receiving treatments for varicosity at donggang social insurance medical clinic were infected with hepatitis c virus. investigations indicated that this aggressive, multisource, and nosocomial hepatitis c virus infection resulted from repeated syringe use among different patients. 6 in july 2011, 15 cataract patients undergoing surgical treatment at an ophthalmic hospital in the raodu district, linfen, suffered from endophthalmitis. investigation showed that patients were infected with pseudomonas aeruginosa endophthalmitis, which resulted from a shortage of surgical equipment and nonstandard disinfection of the surgical instruments. 7 in march 2009, incidence of neonatal nosocomial infection was reported in a maternal and child care service center in the ji county of tianjin. in a neonatal ward, 5 of the total 6 newborns were dead. investigations revealed a severe nosocomial infection resulting in deaths attributed to negligence by staff with poor infection prevention and control standards. 8 the ongoing incidence of such serious events reflects poor standards of nosocomial infection management. first, inadequate medical sources and imbalance in hospital development are increasingly serious challenges. nearly 50 million of the total 1.3 billion people in china require hospitalization annually because of diseases or trauma. however, the chinese health care system is riddled with long wait lists, shortages, and poor equipment because of funding constraints. the national medical system is not hierarchical in structure. as a result, most patients are traditionally segregated in large-and medium-sized hospitals, and hospital wards have become breeding grounds for microbial pathogens, with increased risk of infection. second, the under-reporting of nosocomial infection and the number of full-time staff experienced in infection control have been highlighted by health administrators during the performance appraisal of health care institutions. in some hospitals, hospital leaders neglect poststandardization training and continuing education of the managers involved in controlling infection. full-time professional staff members fail to undergo training in nosocomial infection and occupational health. in most hospitals, target and prospective monitoring are rare, which results in delayed discovery of high-risk areas. third, hospitals lack expertise and human resources skilled in infection management. senior managers fail to consider qualified personnel. a few health care institutions simply fill available vacancies with retired nurses to ensure the number of required personnel in the department of nosocomial infection. forth, drug-resistant bacteria as a result of antibiotic abuse and unreasonable use are still important factors leading to nosocomial infection. epidemiology studies suggest that the usage rate of antibiotics in hospitalized patients in some regions and hospitals is still >60%, reaching a rate of 74.67%, 9, 10 or even exceeding 90% in the neonatal ward. inadequate catheterization and subsequent care along with poor concept of asepsis are other factors. failure to comply with standard regulations of hand hygiene or even handwashing after examining patients with infections, lack of standardized or complete disinfection of surgical instruments, failure to implement surgical standards, failure to consider oxygen humidifiers as an important source of lower respiratory infection, and inappropriate measures of disinfection and isolation are some of the factors that artificially increase nosocomial infection. a solution for improved nosocomial infection management in china has been proposed. the overall goal of the chinese action plan on prevention and control of nosocomial infection (2012-2015) 11 includes enhanced prevention and control of nosocomial infection, insisting on "scientific prevention and control, standard management, highlighting the key points, and enforcing the implementation." the solutions are designed to improve the related technical criteria, upgrade and implement prevention and control measures, raise the professional skills and capacities, and increase the quality and safety of medicines. the following additional steps are recommended to address the challenges of nosocomial infection: • governments at all levels must invest increasingly to improve hospital conditions. public hospitals should be transformed into not-for-profit organizations in the national health care system. • to disseminate the knowledge of nosocomial infection, the government and health workers should popularize and publicize new techniques and know-hows for infection prevention and control. • to improve environmental hygiene, a national system of sanitation should be created to provide population access to adequate sanitation measures given the current unsanitary conditions in hospitals sustainable care and development and nosocomial infection management. the government and the director of the hospital should emphasize the role of rational design of the wards and hospital layout and balance the costs and benefits in prevention of infection. • the hospital information system (his) enables the control of infection by regulating all of the operational aspects, such as medical, administrative, financial, and legal issues and the corresponding services. the his is the essential technologic backup of the environment and infrastructure in a modernized hospital system. information sources related to nosocomial infection may be enriched using the his and enhance the ability of health care professionals. the his facilitates organizations in nosocomial infection management, official documentation, and ensures data security. • evidence-based medicine (ebm) is intended to optimize decision-making by emphasizing the use of evidence from welldesigned research studies. according to the theory of ebm, the strongest evidence based on meta-analyses, systematic reviews, and randomized controlled trials yields strong recommendations. combined with the data of epidemiologic survey and analysis, ebm may provide useful strategies to improve nosocomial infection management. however, the inadequacy of clinical application of ebm in nosocomial infection management in china needs to be addressed. • a no-pay policy by the government and medical insurance organizations must be implemented rigorously for items of nosocomial infection that are not covered by medical insurance. this policy will encourage awareness of prevention and control measures that reduce the incidence of hospital infection. the quality of infection control is an important indicator balancing quality of management and medical administration. during the early period of the severe acute respiratory syndrome epidemic in 2002, the nosocomial infection rate of medical staff reportedly exceeded 10% because of inadequate disease knowledge. however, this rate does not represent all the data because there were several hospitals or wards with a zero infection rate among the medical staff during the outbreak. the discrepancy is associated with different attitudes toward infection. overall, nosocomial infection management in china and worldwide has a long way to go. to the editor: serratia marcescens has become an important cause of nosocomial infections over the last 2 decades. 1 these bacteria can survive on inanimate surfaces and 2% chlorhexidine solutions for months 2, 3 or in medications, and they can subsequently cause outbreaks. 4, 5 although s marcescens strains are usually reported to be a cause of outbreaks, especially in neonatal intensive care units (icus), 6, 7 there are also several reports about these strains causing pseudo-outbreaks. 8, 9 a pseudo-outbreak is defined as the recovery of the same organism from the cultures of patients who are not infected or colonized with the organism. 9 such pseudooutbreaks increase laboratory costs and may lead to unnecessary treatment. leaving the source of contamination undetermined may also eventually cause nosocomial infections. during a 35-day period, 22 s marcescens strains were isolated from 20 patients (19 blood cultures, 2 tracheal aspirates, and 1 urine sample). after isolating the first 4 isolates from blood cultures, the laboratory informed hospital infection control committee. throughout the environmental investigation, the number of isolates reached 22 before the source was determined. these patients were hospitalized in 2 different icus. nearly all of the examined patients (19/ 20) had a history of admittance to the emergency department (ed) on the same day or 1 day before hospitalization in the icus, and some of the patients were transferred to the ed via a common ambulance delivery system. all of the invasive procedures performed on the patients were also examined. most of the s marcescens instances were isolated from the active surveillance cultures that were taken when the patients entered the icus. in addition to these factors, the patients did not have any signs and symptoms compatible with clinical infection. this situation was therefore considered a survey on current status of hospital infection management in 52 medical institutions (master's thesis) the prevalence of nosocomial infection in intensive care units in europe. results of the european prevalence of infection in intensive care (epic) study. epic international advisory committee effect of selective decontamination on antimicrobial resistance in intensive care units: a systematic review and meta-analysis epidemiology of infections acquired in intensive care units procalcitonin levels in patients with positive blood culture, positive body fluid culture, sepsis, and severe sepsis: a cross-sectional study ministry of health. 99 patients were afflicted with infections of hepatitis c virus (hcv) shanxi provincial government. 15 cataract patients suffered from endophthalmitis neonatal nosocomial infections in maternal and child care service center in the ji county of tianjin analysis on incidence of hospital infection and antibiotic usage rational use of antibiotics and preventive medication ministry of health. action plan on prevention and control of nosocomial infection key: cord-259338-q3kw6n9o authors: jean, sim xiang ying; conceicao, edwin philip; wee, liang en; aung, may kyawt; wei, sylvia seow yi; yang, raymond teo chee; qing, goh jia; ting, dennis yeo wu; jyhhan, kuo benjamin; lim, john wah; gan, wee hoe; ling, moi lin; venkatachalam, indumathi title: utilizing the electronic health records to create a syndromic staff surveillance system during the covid-19 outbreak date: 2020-11-04 journal: am j infect control doi: 10.1016/j.ajic.2020.11.003 sha: doc_id: 259338 cord_uid: q3kw6n9o objectives since december 2019, covid-19 has caused a worldwide pandemic and singapore has seen escalating cases with community spread. aggressive contact tracing and identification of suspects has helped to identify local community clusters, surveillance being the key to early intervention. healthcare workers have contracted covid-19 infection both at the workplace and community. we aimed to create a prototype staff surveillance system for the detection of acute respiratory infection (ari) clusters amongst our healthcare workers (hcws) and describe its effectiveness. methods/results a prototypical surveillance system was built on existing electronic health record infrastructure. over a 10-week period, we investigated 10 ari clusters amongst 7 departments. one of the ari clusters was later determined to be related to covid-19 infection. we demonstrate the feasibility of syndromic surveillance to detect ari clusters during the covid-19 outbreak. conclusion the use of syndromic surveillance to detect ari clusters amongst hcws in the covid-19 pandemic may enable early case detection and prevent onward transmission. it could be an important tool in infection prevention within healthcare institutions. late in december 2019, reports of an unknown respiratory virus arose from a seafood market in wuhan, china. since then, sars-cov-2, the causative agent of covid-19 has sparked a global pandemic. (1) healthcare workers (hcws) in singapore have not been exempt from infection, with exposure arising from the community and the work place. (2, 3) there have been various methods described for the surveillance of our hcw groups including regular intermittent pcr testing versus active symptom monitoring. (4) within local institutions, use of real time location tracking devices and institutional temperature recording systems have been utilized as a method of identifying at risk individuals. (5, 6) surveillance is one of the key pillars of infection prevention, enabling early detection and institution of downstream practices that allow reduction in pathogen spread and containment of infection. syndromic surveillance may allow for an even earlier mobilization of response before the causative pathogen is identified and enhance disease containment. increasingly so, institutions are moving away from traditional laborious methods of healthcare surveillance. utilizing the electronic health records, we have created a prototypic surveillance system in the detection of acute respiratory infection (ari) clusters amongst staff and aim to describe its effectiveness in this study. our institution is a tertiary hospital in singapore with approximately 1700 patient beds and employs around 12,000 staff. we implemented the staff surveillance system prototype on 23 rd february 2020 and analyzed data for the first 10-week period till 2 nd may 2020. the aim of this descriptive analytic study is to describe the effectiveness of a prototypic staff syndromic surveillance system in identifying acute respiratory infection (ari) clusters amongst the staff population in the hospital. the main outlets for staff to report sick at our institution are the department of emergency medicine (dem) and the staff clinic (sc). laboratory tests were ordered by physicians in dem or sc at their discretion. we combined data from the electronic health records (ehr) and human resource (hr) data sources to build the syndromic staff surveillance system. using the ehr we identified staff at risk of an ari using the snomed diagnosis codes present on clinical documents. the snomed codes included were, 'upper respiratory tract infection', 'lower respiratory tract infection', 'bronchitis', 'pneumonia', 'tonsillitis' and 'pharyngitis'. given the concerns for an atypical presentation of covid-19 infection (8) at a time when disease had not been sufficiently characterized, 'undifferentiated fever' and 'gastroenteritis' was also included in the analysis. hr databases were utilized to obtain the department of at-risk staff mapped by their associated cost centers. the laboratory database contains respiratory virus multiplex panel that tests for rhinovirus, adenovirus, parainfluenza sub-types 1,2,3 and 4, influenza subtypes a and b, human coronavirus subtypes 229e, nl63 and oc43, metapneumovirus, respiratory syncytial virus subtypes a and b, pcr swabs and covid-19 pcr swabs. the system is be able to differentiate inpatient from outpatient orders based on accounting codes. the institution uses a nation-wide temperature surveillance for outbreak monitoring called s3. this requires all employed staff to input their temperatures within the system twice daily. the s3 system is accessible via the hospital's intranet and to enable easy access, an internet-based form via the formsg platform was created (6) . staff with temperatures of more than 37.5 degrees celsius were deemed as at-risk individuals for purposes of this surveillance system. as staff interaction is not limited to persons within their own department, in order to group them according to their risk association, these at-risk staff presenting to dem or sc were prompted to submit a self-administered questionnaire via formsg separate from the s3 fever declaration system (available at: https://form.gov.sg/#!/5e5b6857130b0100115f3e93). to improve uptake of this questionnaire, it was made accessible through the above link as well as a qr code that was displayed prominently in sc and dem. the fields collected included date of symptom onset, type of symptoms, whether their work involved direct patient contact or exposure to a clinical area in the 2 weeks prior to symptom onset, travel history 2 weeks prior to symptom onset, close contact with other healthcare workers within the institutional campus who had been unwell and close contact with any other persons outside the institution who had been unwell. this provided further granularity to their work locations prior to onset of symptoms as well as work and social contact with persons known to be ill. a network analysis is then applied to information from the formsg to obtain the general distribution of staff with specific symptoms, and their social circles. this network analysis might be able to identify super-spreaders, in particular allied and ancillary health workers and physicians who may not provide location-centric care. for the duration of the study, all at-risk staff, were mapped in time and location by their various departments and locations. the data was aggregated and presented in a heat map for further visualization. baseline data was obtained for the first 2 weeks, following which data was reviewed on a daily basis (monday to friday) and a twice weekly aggregated output was used to set alert thresholds for the emergence of any clusters. a cluster was defined as a signal of >50% the previous baseline or an upward trend for 2 weeks of aggregated results of > 1 standard deviation. the workflow is summarized in figure 1 . the longest lag time between detection of a threshold of a defined cluster till study team detection was three days. upon identification of a cluster, the departmental heads of those clusters were contacted for further information such as rostered location of work, communal eating areas and other symptomatic staff. staff who were symptomatic at the time of review and who had not been assessed at the sc or dem were advised to go to staff clinic where they were seen and swabbed for sars-cov-2. the results of these swabs were tracked by the epidemiology team. during this 10-week period, a total of 8814 unique at-risk staff records were identified, 4712 (53.4%) staff with at-risk symptoms who presented to dem or sc and 4102 staff with fever as self-recorded in the s3 system. of those with at-risk symptoms, 4341 (49.2%) presented to sc and 371 (table 2) . for the network analysis, no outliers were reported because of the restrictions placed to minimize cross-covering of duties. a total of 10 ari clusters in 7 departments were identified amongst staff and later investigated. these involved the following departments in the hospital: radiology, ambulatory endoscopy centre, outpatient pharmacy, medical social services, central operating theatre, emergency department and physiotherapy. amongst these identified departments, 624 (7.1%) staff attended sc or dem, 305 were swabbed for sars-cov-2, of whom 13 were positive and 292 (3.3%) were negative. one staff from the ambulatory endoscopy centre was identified with rhinovirus infection on respiratory virus pcr testing (figure 2a and figure 2b ). of the 13 staff with covid-19, two were within the medical social worker cluster. the first patient presented on 14 th of march 2020, and the large contact tracing and case finding exercise that followed, lead to a surge in staff from this department presenting to sc. this was picked up by the newly initiated surveillance system as a potential cluster. further investigation of the cluster, also revealed a workplace transmission of covid-19 to a colleague within the same department. (2) the remaining 11 covid-19 positive staff were attributed to community acquisition. four of the 13 cases were identified through mass screening of asymptomatic staff as part an essential worker screening exercise. they were not identified by the staff surveillance system as they did not present to dem or sc but were identified after laboratory confirmation of covid-19. the concept of innovative electronic surveillance systems is not novel, clinicians and administrators have long wished to improve upon more traditional methods of gathering and analyzing data. the push in our institution to a fully electronic system has allowed an ehr driven ari cluster surveillance system to develop. these have been utilized within emergency departments and hospitals to act as early warning systems ahead of traditional laboratory surveillance to help reduce the time lag between detection and diagnosis. (9) others have evaluated the feasibility of syndromic surveillance in detecting lower respiratory tract infections and were able to demonstrate detection of legionnaires' disease clusters in a timely fashion. (10) given the time pressure to create a staff surveillance system during the covid-19 outbreak, our system draws from the existing infrastructure of the ehr and building upon various existing data sources. as this staff surveillance system was created early in the covid-19 pandemic when we did not have baseline data to set thresholds, we set arbitrary thresholds based on the prior week results. whilst we managed to demonstrate feasibility, the thresholds will be revised based on cumulative data in the next phase of this study. this initial feasibility study shows that the use of a syndromic surveillance system has the ability to identify ari clusters amongst staff populations that would initiate downstream investigation and active screening. the ari cluster surveillance system managed to identify an ari cluster in the medical social worker group. active contact tracing efforts within the department after the detection of a positive case resulted in heightened alertness of staff towards mild symptoms that may have otherwise gone unnoticed and resulted in increased testing and an increase in attendances to sc and dem by the msw cohort. this was subsequently picked up on our staff surveillance system. it is important to emphasize that having a robust staff surveillance system, does not eliminate the need for good infection prevention practices, active/passive screening and a thriving staff culture aimed at safety and quality. the staff surveillance system requires the presentation of staff to our institutional health services such as sc and dem, those who report sick outside of institution were not captured by this surveillance system. during the covid-19 pandemic, our institution mandated that all staff presented to the institution sc or dem to report sick, only ancillary staff who are not under direct employ were exempt from this rule. as they were a specialized group of staff, specialized measures were undertaken including mass screening. this mandate coupled with strong action taken against presenteeism and data access provided by management aided in the robustness of the system resulting in a near complete data capture. this situation however is unique to the covid-19 pandemic and new thresholds will need to be established as the institutional policies change according to the state of the ongoing pandemic. asymptomatic infections will also not be picked up by this staff syndromic surveillance system. although a large proportion of staff were found to work in inpatient locations based on the formsg survey, no ari clusters were found in staff in inpatient locations. this may be in part attributed to infection prevention measures that were instituted including universal masking for staff as well as use of appropriate ppe and timely patient isolation in inpatient locations. whilst not performed for staff, we also managed to demonstrate a reduction in health-care associated respiratory viral infections during a similar period in the covid-19 pandemic. (11) this may have further reduced the risk of transmission of ari illnesses from patients to staff and indirectly result in a reduction in ari clusters amongst staff in inpatient locations. in one of the investigated clusters, a staff was found to be positive for rhinovirus suggesting a possible etiology for the ari cluster other than covid-19. however, cost concerns resulted in lack of widespread testing for other respiratory pathogens, thus limiting the discovery of other respiratory viral clusters other than covid-19. furthermore, respiratory virus testing resulting in identification of another pathogen may in part help to relieve the on-ground anxiety of staff. due to initial studies suggesting that a gastroenteritis illness may be an atypical presentation of covid-19, to increase data capture this was included as an at-risk presentation. based on our institutional data, and available current literature, such symptoms are low in covid-19 and this will be revised moving forth. future directions to create a more robust surveillance system within the institution include creating a patient syndromic surveillance system, meshing output from both systems and incorporating geospatial mapping to allow for better visualization of ari clusters. further review of thresholds with the current collected data is also planned for the next phases of the staff surveillance system. our study demonstrates the feasibility in utilizing the ehr in the detection of ari clusters amongst hospital staff. this will aid in the early detection of aris including covid-19. hence, the staff syndromic surveillance system is an important component of the hospital's infection prevention efforts to prevent healthcare associated covid-19. world health organisation coronavirus disease (covid-19) pandemic containment of covid-19 cases among healthcare workers: the role of surveillance, early detection, and outbreak management healthcare workers in singapore infected with covid-19 monitoring approaches for health-care workers during the covid-19 pandemic use of a real-time locating system for contact tracing of health care workers during the covid-19 pandemic at an infectious disease center in singapore: validation study responding to the covid-19 outbreak in singapore: staff protection and staff temperature and sickness surveillance systems overview of sentinel systems for hospitalized severe acute respiratory infections (sari) represented in the weekly euroflu surveillance bulletin covid-19 and the gastrointestinal tract: more than meets the eye emergency department syndromic surveillance providing early warning of seasonal respiratory activity in england syndromic surveillance for local outbreaks of lower-respiratory infections: would it work reduction in healthcare-associated respiratory viral infections during a covid-19 outbreak our team would like to acknowledge all staff within the institution who have contributed in covid-19 pandemic efforts. this work was not grant funded. the authors have no conflict of interest to report. waiver of consent was obtained from institutional irb ( key: cord-275552-ijxxeo27 authors: yen, zui-shen; chang, chee-jen; chen, shey-ying; lee, chien-chang; hsu, chiung-yuan; chen, shyr-chyr; chen, wen-jone title: how much would you be willing to pay for preventing a new dangerous infectious disease: a willingness-to-pay study in medical personnel working in the emergency department date: 2007-10-10 journal: am j infect control doi: 10.1016/j.ajic.2006.09.008 sha: doc_id: 275552 cord_uid: ijxxeo27 background: the risk of developing nosocomial infectious diseases among medical personnel in the emergency department (ed) can result in tremendous psychologic stress. the objective of this study was to estimate the median amount of money ed personnel would be willing to pay for preventing nosocomial severe acute respiratory syndrome (sars). methods: a contingent valuation approach with close-ended format was used. during the study period from june 15, 2003 through june 30, 2003, a convenience sample of all medical personnel working in the ed of national taiwan university hospital was carried out. participants were interviewed by a standard questionnaire and were asked to choose whether or not they would pay at a specified price to purchase a hypothetical sars vaccine. a logistic regression model was created to evaluate the relationship between willingness-to-pay and the log of the price offered in the bid questions. the median and mean amounts of willingness-to-pay were calculated. results: a total of 115 subjects were interviewed and most were nurses (68.7%). the median and mean amount subjects reported being willing to pay for a sars vaccine was us $1762 and us $720, respectively. subject responses were significantly related to the price of vaccination and their type of job. conclusions: medical personnel in the ed reported that they would be willing to pay substantial monetary amounts for preventing nosocomial sars. severe acute respiratory syndrome (sars) can spread extensively among health care workers in various settings. 1 the use of precautions, such as n95 masks, gloves, and gowns, can reduce nosocomial transmission of sars. 2 despite the adoption of such precautions, clusters of sars cases still occurred among properly protected medical personnel in the emergency department (ed) of national taiwan university hospital (ntuh) in 2003 may. nine medical personnel developed illness that met the criteria for the world health organization case definition of suspected or probable sars. 3 a comfortable protective device that is suitable for long-term usage in eds or vaccination may be needed to fully protect medical personnel in eds from nosocomial transmission of sars. until such an ideal protective device or vaccination is available, medical personnel in eds will continue to face the psychologic stress associated with the risk of contracting a potentially fatal illness. the contingent valuation method (cvm) is an established research method for valuing nonmarket goods. 4 cvm was initially applied to questions of environmental interest, such as wildlife preservation and water quality. 5, 6 more recently, cvm has been used to estimate the value placed by people on such health care intervention as in vitro fertilization, 7 and autologous blood donation. 8 this method provides a means of acquiring monetary estimates of the value placed on intangible outcomes. 9 in this study, cvm was used to estimate the median amount emergency medical personnel would be willing to pay for a hypothetical vaccine to prevent developing nosocomial sars. this sum may serve as a quantitative proxy measure for factors such as workers' anxiety and distress in facing the threat from sars. this study surveyed the willingness of medical personnel to pay for a hypothetical vaccine. this study was approved by the institutional review board of ntuh. the study was conducted among medical personnel working in the ed of ntuh, a 2000-bed public, tertiarycare, university-based medical center in taipei city with an annual ed census of approximately 110,000 patients. the ed is staffed primarily by staff physicians and emergency medicine residents along with rotating residents from the internal medicine, surgery, and pediatrics departments. all participants were medical personnel, including nurses, residents, and staff physicians, who were serving in the ed of ntuh during june 2003. subjects were interviewed with a standardized questionnaire and were compensated us $3 in small gifts for their time and efforts. medical personnel were considered ineligible for participation if they had just started employment in june 2003. during the study period from june 15th, 2003 to june 30th, 2003, a convenient sample of all the medical personnel working in the ed of ntuh was carried out. the 9 cases of sars were excluded. all the participants were interviewed by the authors with a standardized questionnaire. the questionnaire assessed demographic information, risk perceptions, and willingness-to-pay (wtp) for a hypothetical safe and effective vaccination. subjects indicated their perceived risk of acquiring nosocomial sars infection by selecting 1 of 5 different fixed response alternatives: 1/100, 1/1000, 1/10,000, 1/100,000, and 1/1,000,000. the time frame for the perceived risk is lifetime. to determine the monetary value of the precautions to our subjects, each subject was asked the following question: ''suppose there was a vaccine that could fully protect you from developing nosocomial sars. knowing what you know now, would you pay $x out of pocket for such a vaccine?'' in the question for determining the monetary value of the vaccination, $x was selected at random from a group of 9 bids ranging in value from 1000 to 1,000,000 new taiwan dollars (nt$). for the convenience of international comparison in the future, these values (in nt$) were then converted to 2003 us dollars at the rate of nt $34.96 : us $1 in further data processing. 10 subjects could provide either a ''yes'' or ''no'' response to the question, indicating whether they were willing to pay for the hypothetical vaccine at the price they had been quoted. a logistic regression model was created to evaluate the relationship between wtp and the log of the price offered in the bid questions. in this regression model, we evaluated whether the probability of answering ''yes'' to the wtp) questions was related to the price listed. data on the median and the mean wtp were reported. the effect of social-economic factors and different perceived risks of acquiring nosocomial transmission of sars on wtp were assessed through the creation of a multivariate logistic regression model with a backward elimination algorithm. 11 all statistical analyses were performed with sas version 8.1 (sas institute, cary, nc). during the study period, 120 subjects out of 158 ed personnel in total were recruited. five subjects were unwilling to respond to the questionnaire. the characteristics of the remaining 115 participants are outlined in table 1 . the average age of study participants was 30.5 years, and 67.0% were women. sixty-nine percent of participants were nurses, and 57% had graduated from college. annual incomes of 41% of the participants were equal to or more than us $28,604. among the 115 subjects who responded to the wtp question, a strong negative association was seen between the log of the dollar bid presented and the subject's wtp for a vaccine that could avert their development of nosocomial sars infection ( table 2 ). the odds ratio (or) for wtp associated with a 10 fold increase in the bid presented to the study subject was 0.20. this suggests that in this sample, the odds of a person willing to pay for a vaccine costing us $100 would be 0.20 times the odds of wtp for a us $10 vaccine. a fitted logistic curve of the expected proportion of subjects willing to pay for a vaccine over a range of costs is presented in fig 1. the projected median amount subjects would be willing to pay was us $1762. thus, presented with a vaccine costing us $1762, half the study subjects would have been expected to agree to purchase it. the mean amount our study subjects would be willing to pay was us $720. a multivariable logistic regression model was created to adjust for potential confounding of wtp by subject-related covariates. in this multivariate model, we found the price of the vaccine and the type of jobs were significantly related to the wtp responses. the wtp responses were not significantly related to age, gender, perceived risk, education level, or income level. increased amount of wtp was found in resident physicians as compared with nurses (or, 12.06; 95% confidence interval [ci], 1.54-94.48). when adjusted for this confounding variable, the median amount subjects were willing to pay was us $2729, us $3922, and us $1333 in staff physicians, resident physicians, and nurses, respectively. sars, avian flu, and other dangerous infectious diseases present a constant and significant threat to the health of medical personnel in eds. the importance of recognizing the intangible costs of nosocomial transmission of these infectious diseases cannot be overemphasized. economic analyses that include the costs of workers' anxiety and distress are likely to provide a more favorable assessment of a new vaccination. we used this study as an example to demonstrate that medical personnel would be willing to pay substantial monetary amounts to avert the risk of nosocomial sars infection. there are several clinical implications of our results. first, the anxiety and psychologic stress of healthy workers when they are facing threats from dangerous infectious diseases can be measured quantitatively or monetized. the estimates of wtp can be used as a reference to improve benefits and compensation for those healthy workers. second, to policy makers, the preference assessment can also be of great assistance in guiding decisions on resource allocation. the aggregate wtp will be a substantial dollar amount and provide a solid ground for the investment in new vaccine development or more effective protective measures. based on our results, medical personnel in the ed showed very strong preference for a sars vaccine. the usual costs of vaccines are all below or around us $10 in taiwan. however, we found that the median amount medical personnel in the ed would be willing to pay for a sars vaccine was us $1,762, which was exceedingly high compared to the usual cost of a vaccine and equal to 14% of the 2002 taiwan gross domestic product per capita (us $12,588). 12 dashed line, median amount subjects would be willing to pay. subjects refused to answer the question. while the sars vaccine is still under development, the only effective mechanism for containment of sars is quarantine. the cost of quarantine was estimated at can $2611 to can $4150 per averted infection in canada. 13 however, with the probability of infection among ed workers of ntuh around 0.07, the implied benefit per averted infection was approximately us $25,000 ($1762/0.07). compared with the cost of quarantine, the potential benefit assessed by cvm was much larger. it may suggest that it's worth investing more resources in the control of sars. incorporating the monetary value of wtp in the cost-benefit analysis of a sars vaccine would provide a more favorable result from the perspective of ed workers. income-sensitivity (ie, differential wtp according to income) is an important issue in assessing wtp for health technologies because it raises crucial questions about equitable distribution of health resources. we did find income-sensitivity in our study. however, the responses of our participants were related to their job description, a surrogate measure of income, and education level. data on factors such as marital status or the presence of dependent children, which could affect risk attitudes by increasing the circle of people who suffer the consequences of sars infection by a family member, may be needed to explain the results. assessment of the effect of the perceived risks that might confound wtp for a hypothetical sars vaccine in this study revealed no significant positive or negative relationship between the perceived risks of developing nosocomial sars infection and wtp for a sars vaccine. this result was not consistent with the findings of a study by bosompra et al of psychosocial factors associated with the public's wtp for genetic testing for cancer risk. 14 it is possible that the number of our participants was not large enough to detect the effect on wtp for a sars vaccine was largely explained by the price of vaccination. these questions warrant additional exploration. several formats of wtp survey questions, such as open-ended questions, closed-ended questions with dichotomous choice, and payment card questions, are currently in use. many cvm researchers still do not agree about which valuation question is the most appropriate. 4, [15] [16] [17] open-ended questions has been used in early cvm applications but are relatively difficult to answer. a payment card valuation question is an improvement over the open-ended valuation question, but some arguments exist as to whether there are range and centering biases. 15, [18] [19] following the recommendation and praxis of some health economic studies, [8] [9] 17, 20 the closed-ended question with dichotomous choice was used in this study. the advantage of the dichotomous choice question is that each respondent is asked a single valuation question that is relatively easy to answer. the major disadvantage is that the cvm researcher only learns the threshold of each respondent's wtp, and more sophisticated econometric methods are necessary to develop an average wtp amount. 15 even with adjustments for some important factors, values for other populations may differ. our results included both the median amount subjects would be willing to pay and also the corresponding percentage of gross domestic product per capita to allow comparison of our results with studies from other countries. however, as with other studies in health care, extrapolation of population results to the behavior of particular individuals must be made with caution. participants were not actually forced to pay the amount they claimed they would have been willing to provide; 21 nonetheless, the decrease in wtp as bids increased suggests that subjects were price-sensitive, notwithstanding the hypothetical nature of this transaction. this pilot study was intended to illustrate the importance of assessing intangible costs associated with a dangerous infectious disease. the number of participants in the study was not very large. the survey respondents were all ed personnel in a hospital that experienced an outbreak of sars. further studies are needed to determine whether our results can be generalized to other populations. in conclusion, medical personnel in the ed reported that they would be willing to pay substantial monetary amounts for preventing nosocomial sars. we suggest these findings should be considered in further studies for promoting safety of medical care providers. the authors would like to thank hsin-yi chen for her help in the statistics. cluster of severe acute respiratory syndromes cases among protected health-care workers-toronto, canada and advisors of expert sars group of hospital authority. effectiveness of precautions against droplets and contact in prevention of nosocomial transmission of severe acute respiratory syndrome (sars) world health organization. case definitions for surveillance of severe acute respiratory syndrome (sars) contingent valuation of health option price estimates for water quality improvements: a contingent valuation study for the monongahela river a comparison of stated preference methods for environmental valuation the willingness to pay for in-vitro fertilization: a pilot study using contingent valuation patients' willingness to pay for autologous blood donation willingness to pay to avoid sharps-related injuries: a study in injured health care workers foreign currency exchange rate. taipei: statistics taiwan selecting the best regression equation: applied regression analysis and other multivariable methods gross domestic product per capita. taipei: statistics taiwan the economic impact of quarantine: sars in toronto as a case study psychosocial factors associated with the public's willingness to pay for genetic testing for cancer risk: a structural equations model a practitioner's primer on the contingent valuation method can hypothetical questions reveal true values? a laboratory comparison of dichotomous choice and open-ended contigent values with auction values eliciting willingness to pay: comparing closed-ended with open-ended and payment scale formats a test for payment card biases the contingent valuation method in health care outcome measurement in economic evaluation hypothetical versus real willingness to pay in the health sector: results from a field experiment key: cord-288589-bt9429bh authors: habibzadeh, farrokh title: hadj ritual and risk of a pandemic date: 2013-12-31 journal: am j infect control doi: 10.1016/j.ajic.2013.08.011 sha: doc_id: 288589 cord_uid: bt9429bh nan at mass gatherings such as the hadj, one of the greatest islamic rituals, pilgrims are exposed to various infectious agents. 1 the pilgrims bring home not only souvenirs but also various infectious agents, as is evident from an increase in the incidence of infectious diseasesdmainly flu-like syndromesdin returning pilgrims every year. from early october 2013, saudi arabia will be hosting millions of muslims from different parts of the world who travel to saudi arabia to participate in the hadj. however, since november 2012, saudi arabia has also hosted a new fatal viral infection: the middle east respiratory syndrome coronavirus (mers-cov). coronaviruses are enveloped, single-stranded, positive-sense rna viruses. the first known occurrence of mers-cov in human was reported in a patient with severe acute respiratory infection in april 2012, in jordan. 2 later, person-to-person transmission was reported, 3 which is very important because it might result in a switch from aborted outbreaks to a pandemic, which was probably the case for the severe acute respiratory syndrome (sars) coronavirus outbreak in 2003-2004. as of august 13, 2013, 94 laboratory-confirmed cases of human infection with mers-cov had been reported to the world health organization, 46 (49%) of which have been fatal. the age of the affected patients ranged from 14 months to 94 years (median, 50 years). the incubation period of the infection is estimated at 1 week, based on the available data. 4 mers-cov has a high mortality rate of almost 50%, and thus the possibility of a pandemic is worrying. soon after pilgrims return home, they hold ceremonies and invite relatives and friends to celebrate their return from hadj, which provide further opportunities for the spread of the virus. there are many reasons to convince us that mers-cov represents a high risk: a deadly virus that can be transmitted from person to person, a mass gathering of millions of people from different parts of the world at the epicenter of the infection, an incubation period that provides enough time for pilgrims to return home and disseminate the virus, ceremonies that place relatives and friends in close contact with infected individuals when they return, and signs and symptoms that can easily be mistaken for common postpilgrimage flu-like syndromes. 5 this year, health care workers should be more alert to identify the probable cases of mers-cov infection as early as possible. the total risk may not be very high, but, considering the devastating outcome for the middle east in particular, and world at large, it would be wise to take into account even minute risks and take all possible safety precautions into action. emergence of medicine for mass gatherings: lessons from the hajj isolation of a novel coronavirus from a man with pneumonia in saudi arabia clinical features and viral diagnosis of two cases of infection with middle east respiratory syndrome coronavirus: a report of nosocomial transmission middle east respiratory syndrome coronavirus (mers-cov), update middle east respiratory syndrome coronavirus: the unseen menace key: cord-273604-0w5shxmf authors: psevdos, george; papamanoli, aikaterini; barrett, nancy; bailey, lisa; thorne, monique; ford, florence; lobo, zeena title: halting a sars-cov-2 outbreak in a u.s. veterans affairs nursing home date: 2020-11-03 journal: am j infect control doi: 10.1016/j.ajic.2020.10.022 sha: doc_id: 273604 cord_uid: 0w5shxmf a veterans affairs long term care facility on long island new york was confronted with a covid-19 outbreak in late march to mid-april 2020. faced with a dwindling supply of ppe, the infection control team distributed supplies saved for a possible ebola outbreak; a covid unit was created within the nursing home facilitating the geographic isolation of cases; universal testing of residents and employees allowed for the implementation of proper quarantine measures. it was a multidisciplinary team approach led by the infection control team that successfully contained this outbreak. reported. 5 in a review of over 9,000 nursing homes from the us, covid-19 outbreaks were more related to facility size, location-with massachusetts and new jersey having the greatest number of affected facilities-and greater percentage of african american residents. 6 the last mentioned fact mirrors a critical health disparity seen in this pandemic at large, namely african americans contracting sars cov-2 at higher rates and are more likely to die. 7 although nationally the virus spreads like wildfire in nursing homes (among residents and working staff), the department of veterans affairs (va) reported lower covid-19 rates in their affiliated nursing homes in a u.s. congressional hearing. 8 we discuss here our experience in facing a covid-19 outbreak in our va affiliated nursing homes. northport veterans affairs medical center provides hospital-based acute medical and psychiatric care for u.s veterans, as well as long-term/extended nursing home and residential mental health program care. the nursing homes are structured as community living centers (clcs), with a 139 total bed capacity. there are four clcs, clc1 to 4, which include mental health (clc3) and hospice care units (clc4). the covid-19 outbreak involved clc 1 and clc2, both totaling 80 beds. veterans are eligible to live in the clcs if they have service-connected disability (70% or more)-a disability assigned to them by the department of veterans affairs based on injury or illness that incurred, or, was aggravated during active military service. clc 1 and 2 units admit veterans with complex underlying medical issues that can include immobility due to stroke and cardiovascular disease, continuous oxygen requirement due to chronic obstructive lung disease, end stage renal disease on dialysis, complex wound care, chemotherapy, prolonged intravenous antibiotic therapy, and other rehabilitation needs. patients, five remained asymptomatic, nine got hospitalized, six died. the mortality rate was 24%. no coinfection with influenza or other respiratory viruses was identified. table 1 summarizes the demographic characteristics, medical history and laboratory findings of the patients. the median age was 74 years, with no difference in age between recovered and diseased., 73 vs. 77, p: 0.105. simplified acute physiology score (saps) ii was higher in the deceased group (p:0.001) and so were d-dimer (admission and peak levels), c-reactive protein, lactate dehydrogenase, and peak ferritin and procalcitonin levels. see table 1. during this outbreak, 11 hcps were diagnosed with covid 19 and all recovered. among the patients who recovered, 13 had persistent positive nasopharyngeal rt-pcr for average 32 days (range 19 to 52 days) since diagnosis. seven out of these thirteen were tested for sars-cov-2 igg antibody (abbott, lake forrest, il) and were all positive. the median incubation period for a symptomatic sars-cov-2 infection is 5 days; symptoms can appear within 12 days of infection. 11 how effective the creation of a covid unit inside the nursing home can be; cohorting of cases allowed for residents to stay in familiar grounds, enabled the restriction of staff movement between the wards, and overall reduced the potential of viral transmission. 13 universal testing of residents (first aiming close neighboring residents and then every resident) and hcps was another principal measure to successfully interrupt the outbreak. eckardt et al, demonstrated that a productive structured 14-day interval universal testing in their long-term care facility aided to contain the spread of the virus in a six-week period. 14 implementing the measures described above we managed to suppress the outbreak within 3 weeks in both clc 1 &2. at this writing there are no active covid-19 cases in our clcs. we followed the cdc's proposed test-based strategy to remove covid-19 precaution/isolation measures. this had the unfortunate effect of keeping residents longer on strict isolation as their rt-pcr tests remained positive, even though they had recovered or remained asymptomatic and had also developed an igg antibody. the cdc has since updated their guidelines regarding discontinuation of transmission-based precautions, no longer requiring a testbased strategy for asymptomatic or patients with mild disease. 15 prolonged positive sars-cov-2 rt-pcrs, up to five weeks, have been reported in many studies; the rna detected in these cases is likely from nonviable virus. a proposed way of how to interpret the pcr test in these cases is to utilize the cycle threshold (ct) value .16 this value is not reported to the clinician but can be reported upon request. it is part of the rt-pcr test, with a specified threshold for a positive result, and it is inversely related with the viral load. a ct value of >34 likely denotes non transmissible disease. 16 exploring this potential strategy in more rigorous studies could shorten duration of isolation, conserve tests, reagents, and ppe. in conclusion, sars-cov-2 infection can spread rapidly within skilled nursing facilities and can potentially cause high morbidity and mortality. swift detection by rapid rt-pcr testing of all asymptomatic carriers (residents and employees via universal testing) and implementation of strict infection control and isolation measures are pivotal in containing and thus eliminating a covid-19 outbreak. indeed, the infection control team working closely with the dedicated nursing home staff, are both the unsung heroes of the robust and unyielding defense against a formidable virus. legends: table 1 : demographics, laboratory findings, outcomes of covid-19 clc cohort who declares covid-19 a pandemic epidemiology of covid-19 in a long-term care facility in king county covid-19 and the elderly: insights into pathogenesis and clinical decision-making characteristics of u.s. nursing homes with covid-19 cases covid-19 and african americans jama 2020 va touts lower clc covid-19 rates vs. community nursing homes centers for disease control and prevention. testing guidance for nursing homes. interim sars-cov-2 testing guidelines for nursing home residents and healthcare personnel the incubation period of coronavirus disease 2019 (covid-19) from publicly reported confirmed cases: estimation and application presymptomatic sars-cov-2 infections and transmission in a skilled nursing facility universal and serial laboratory testing for sars-cov-2 at a long-term care skilled nursing facility for veterans hospital affiliated long term care facility covid-19 containment strategy by using prevalence testing and infection control practices discontinuation of transmission-based precautions and disposition of patients with covid-19 in healthcare settings acknowledgements: the authors would like to thank our veterans, and the nursing home staff, the facility leadership, the laboratory staff for their help during this pandemic. covid acei ace inhibitor, arb angiotensin receptor blocker, bmi body mass index, cad coronary artery disease, chf congestive heart failure, copd chronic obstructive lung disease, crp c-reactive protein, ldh lactate , neg negative, dehydrogenase, saps ii simplified acute physiologic score ii, sbp systolic blood pressure key: cord-259461-ig9g1o8b authors: choi, jeong sil; kim, kyung mi title: effects of nursing organizational culture and job stress on korean infection control nurses’ turnover intention date: 2020-04-11 journal: am j infect control doi: 10.1016/j.ajic.2020.04.002 sha: doc_id: 259461 cord_uid: ig9g1o8b this study's aim was to discern the nursing organizational culture and job stress, induced by infection control nurses (icns)’ working together, affects icns’ turnover intentions. job stress was the most significant factor affecting icns’ turnover intention. to reduce icns’ turnover intention, their task stress needs to be lowered and managed. in particular, efforts should be made to establish a relation-oriented organizational culture that values positive relationships while enhancing their community spirit at the organization level. recently, medical institutions have experienced a serious shortage of nursing staff internationally, and the turnover of professional nurses has become a threat to providing high-quality medical services. 1 in particular, because infection control nurses (icns) are professionals with significant clinical experience and qualifications, reducing their turnover is essential for effective human-resource management. 1 in 2015, when the middle east respiratory syndrome outbreak occurred in south korea, the number of professionals performing infection-control tasks increased rapidly, with the revision of medical law related to infection control in 2016. 2, 3 icns experience stress from their roles as professional nurses, excessive work load, and the lack of personnel and other support from nursing organizations. 4, 5 these reasons may cause icns' turnover intention, which in turn may bring about actual turnover, resulting in their career discontinuation. 1, 2 turnover intention ranges between thoughts of leaving and the action of leaving, and is considered the most important variable preceding actual turnover. 6 turnover intention is affected by organizational factors such as job stress, various types of organizational culture, and leadership, 7,8 as well as by personal factors such as demographic characteristics. 1 organizational culture includes relation-oriented culture, innovation-oriented culture, task-oriented culture, and hierarchy-oriented culture. 8 a relation-oriented culture focuses on human relationships and values such as trust, participation through teamwork, loyalty, and morale. 8 an innovation-oriented culture values organizational change and inventiveness with a focus on patients' satisfaction, and recognizes creativity and entrepreneurship as central values. 8 a task-oriented culture emphasizes productivity in achieving organizational performance and carrying out tasks and values external orientation and stability. 8 a hierarchy-oriented culture emphasizes stability, but also order and procedure among members of the organization. 8 this study aimed to understand the nursing organizational culture and job stress created by icns working together, affected turnover intention, and the general characteristics influencing it. another aim of this study was to identify the current status of turnover intention of the rapidly increasing number of icns, and provide basic data for the efficient management of personnel. of the 500 icns currently carrying out infection-control work who attended the 2018 summer conference held at the korea association of infection control nurses, 230 icns agreed to participate. two researchers distributed the questionnaire to participants during the conference. the researchers used g-power 3.1.3 to calculate the sample size. the effect of multiple regression analysis was under the condition of a medium effect size of 0.15, a significance level of 0.05, power of 0.90, and a total of 15 independent variables. the data collection was performed with 230 icns, considering the dropout rate based on the least sample size (199 samples). an institutional review board approved the study. the questionnaire comprised 4 sections: general characteristics, nursing organizational culture, job stress, and turnover intention. responses to 20 questions on nursing organizational culture were measured using a tool in korean developed by kim, han, and kim. 8 this 5-point likert-type scale survey consisted of relationoriented culture, task-oriented culture, innovation-oriented culture, and hierarchy-oriented culture. the higher the score for each culture type, the more strongly one recognizes that culture. cronbach's a was 0.88 in kim et al, 8 and 0.78 in this study. job stress includes any kind of job-related stress and was measured with a tool developed by parker and decotiis. 9 using the tool's 5-point likert-type scale, the higher the score, the higher the stress level. cronbach's a was 0.78 in the parker and decotiis' study, 9 and 0.93 in this study. turnover intention is defined as the intention of members to voluntarily leave the organization. this study used tools developed by lowler, 10 modified and supplemented for nurses by shin and cho. 11 responses were measured on a 5-point likert-type scale: the higher the score, the higher the turnover intention. cronbach's a was 0.88 in shin and cho, 11 and 0.79 in this study. differences in turnover intention according to general characteristics were analyzed by independent t tests and anova. correlations were computed using pearson's correlation tests. hierarchical multiple regression analysis was performed to verify the factors of turnover. in step 1 of the turnover intention regression model, job stress was selected as a significant variable in previous studies 4, 7 and each type of nursing organizational culture 6, 7, 8 step 2. the statistical significance level was p < .05. from the 230 participants, data of only 202 were used for the analysis, after removing 14 incomplete responses and 14 responses from those who did not belong to a medical institution. all 202 participants' infection-control practice experience was relatively short at average of 3.68 § 3.81 years. further, 64% of icns were novices with less than 3 years of work experience. the hierarchy-oriented culture scored highest (3.40 § 0.58). the average score for job stress (score range 1-5) was 3.48 § 0.79, and that of turnover intention (score range 1-5) was 3.10 § 0.92. turnover intention showed no significant difference according to participants' characteristics (p < .05) ( table 1) . a correlation analysis between turnover intention and the subdomains of nursing organizational culture showed that turnover intention negatively correlated with relation-oriented culture (r = -0.305, p < .001), innovation-oriented culture (r = -0.150, p = .033), task-oriented culture (r = 0.219, p = .002), hierarchy-oriented culture (r = 0.178, p = .011), and job stress (r = 0.443, p < .001). effects of nursing organizational culture and job stress on turnover intention in step 1, job stress was a significant factor in turnover intention (b = 0.443, p < .001), with an explanatory power of 19.2%. when considering 4 subdomains of nursing organizational culture in step 2, relation-oriented culture (b = -0.199, p = .027) was a new influential factor that significantly affected turnover intention, with an additional explanation power of 4.1%. the total explanatory power of the 2 variables of job stress and relation-oriented culture on turnover intention was 23.3% (table 2) . organizational factors such as organizational culture and job stress predict the turnover intention of general nurses 7, 8, 11 ; it is important to explore how these factors affect turnover intention in newly established infection-control organizations. in this study, too, job stress was the factor with the strongest influence, aligned with previous studies. relation-oriented organizational culture was observed, for the first time, as the factor with the next strongest influence. many icns report experiencing significant stress from their infection-control tasks, conflict over their roles as professional nurses, excessive work, psychological pressure from institutional assessments, and lack of infection control knowledge. 1, 4, 5 because these stress factors may eventually lead to actual turnover and discontinuation of their infection-control work, proper compensation along with professional and administrative support are necessary to manage job stress and help nurses adapt to the organization. 4, 8, 11 in the analysis, correlating with turnover intention, organizational culture, in which new relationships were formed by 2 or more nurses working together to perform a task (not working alone in infection control), showed lower turnover intention; relation-oriented organizational culture and the innovation-oriented culture scored higher. these correlations were similar to those in general nursing organizations, 8, 9 and the results were the same as those in a preceding study in that relation-oriented organizational culture was the main influential factor that significantly affected turnover intention. 12 therefore, an infection-control department composed of experts from nursing organizations should pay attention to relation-oriented culture and develop new strategies to establish this culture: organizations should make efforts to foster a sense of community in an organizational dimension and to place importance on positive relationships. the results are expected to help infection-control organizations manage staffing in a stable and efficient manner by lowering icns' turnover intention, allowing icns to manage their job stress and establish a relation-oriented organizational culture. the limitation of this study is that it was conducted only with icns in a single country. additional studies should compare data from various countries. study results also suggest adding infection-control doctors and clinical pathologists as participants. researchers could query these members of the same teams to identify job differences and explore additional variables such as task satisfaction, leadership, organizational immersion, and empowerment at an organizational level. 1, 7, 8, 12 computed by independent hierarchical multiple linear regression analysis, p < .05*. job embeddedness factors as a predictor of turnover intention among infection control nurses in korea crisis prevention and management by infection control nurses during the middle east respiratory coronavirus outbreak in korea improve infection control of hospitals by establishing infection prevention and control fee a study on work condition, stress, role conflict and job satisfaction of infection control nurses working in general hospitals changes of the core competency of infection control nurses in accordance with the new law supporting infection control manpower meta-analysis of antecedents and correlates of employee turnover: update, moderator tests, and research implications for the next millennium impact of job satisfaction components on intent to leave and turnover for hospital-based nurses: a review of the research literature the development of the nursing organization culture measurement tool organizational determinants of job stress. organ behav and hum perform satisfaction and behavior relationship between job stress and turnover intention among nurses in university hospitals effects of job characteristics, organizational culture on job satisfaction and turnover intention in public institution nurses key: cord-282272-wy8do2z6 authors: nelson, atiba; kassimatis, jennifer; estoque, jay; yang, cicely; mckee, geoff; bryce, elizabeth; hoang, linda; daly, patricia; lysyshyn, mark; hayden, althea s.; harding, john; boraston, suni; dawar, meena; schwandt, michael title: environmental detection of severe acute respiratory syndrome coronavirus 2 (sars-cov-2) from medical equipment in long-term care facilities undergoing covid-19 outbreaks date: 2020-07-06 journal: am j infect control doi: 10.1016/j.ajic.2020.07.001 sha: doc_id: 282272 cord_uid: wy8do2z6 we conducted environmental sampling at long-term care facilities to determine the extent of surface contamination with sars-cov-2 virus. medical equipment used throughout the facility was determined to be contaminated. outbreaks abstract: we conducted environmental sampling at long-term care facilities to determine the extent of surface contamination with sars-cov-2 virus. medical equipment used throughout the facility was determined to be contaminated. keywords: sars-cov-2, covid-19, long-term care, infection control, environmental sampling background: sars-cov-2 outbreaks in community long-term care facilities have primarily been linked to person-to-person transmission; however, despite implementation of enhanced infection control measures limiting person-to-person transmission potential, many long-term care facilities continue to report new cases and outbreaks. 1 environmental contamination with sars-cov-2 virus has been hypothesized to propagate spread; however, the extent to which environmental contamination occurs in long-term care settings has yet to be fully understood. 2, 3 we conducted environmental sampling to assess the extent of surface contamination with sars-cov-2 virus within long-term care facilities with declared covid-19 outbreaks. we assessed surface sars-cov-2 contamination at three licensed long-term care facilities with declared covid-19 outbreaks within a canadian metropolitan city. each longterm care facility services over 150 residents and provides room and board, management of medical conditions and assistance with activities of daily living. 4 environmental samples were collected from high-touch surfaces, communal sites, and mobile medical equipment at various sites in each of the three facilities. sampling sites were selected based on the distribution of covid-19 cases within the facility, areas common to case clusters, and the advice of an infection prevention and control specialist. patient rooms and patient bathrooms were excluded from sampling, as the presence of sars-cov-2 in the personal areas of patients diagnosed with covid-19 was expected. overall 89 sites were sampled. table 1 details the sites sampled at each facility. sampled sites included 20 (22·5%) sites in staff communal areas, and 60 (67·4%) sites in care provision areas; for example, nursing stations, and related medical equipment. seven sites (7·9%) in an institutional kitchen were also sampled, as well as 2 sites (2·2%) at a main entrance of a facility. eighty-four (94·3%) of the 89 sites were negative for both sars-cov-2 virus targets. six (6·7%) sites tested positive or indeterminate for the sars-cov-2 virus: two from each of the three facilities. the six sites with detected sars-cov-2 included the bladder of a normal adult size, reusable blood pressure cuff (e gene cycle threshold: 39·18) (image 1) and the bladder of the large adult size, reusable blood pressure cuff (38·6) (image 2) in facility one (table 1) ; the touch fastening strap of a reusable blood pressure cuff (38·65) (image 3) and the handle of a mobile linen cart (38·54) (image 4) in facility two (table 1) ; the bladder of a reusable blood pressure cuff (37·38) (image 5) and the touch display of an electronic medication administration record (mar) tablet (38·48) (image 6) in facility three ( table 1) . the lowest cycle time for a sample with sars-cov-2 detected was from the bladder of the blood pressure cuff in facility three (37·38). four (44%) of 9 environmental samples taken from blood pressure cuffs contained detectable levels of sars-cov-2 viral rna. environmental contamination with sars-cov-2 virus was detected at each of three covid-19 outbreak facilities sampled in this study, including surfaces of five frequently used medical devices transferred between patient rooms, and one high-touch surface used by care staff this study contains limitations. the swabs used were not validated for environmental sampling, and the sensitivity of their use for the novel virus sars-cov-2 is not known. additionally, all samples with viral rna detected recorded a ct value greater than 24, a level at which the detected virus may not be infectious in the context of a human nasopharyngeal sample infecting vero cell lines. 7 however, although the cycle threshold values for these six samples were above an observed threshold for sars-cov-2 vero cell infectivity, infectious levels of the virus may have been present before an environmental sample was taken. future studies focusing on environmental contamination with sars-cov-2 are required to confirm these results and explore other mechanisms of environmental transmission in the long-term care environment. given the ubiquity of blood pressure cuffs throughout acute and community healthcare settings, further research should also explore their role as fomites for sars-cov-2 transmission. our findings suggest medical equipment is a potential environmental route for transmission of sars-cov-2 virus in long-term care facilities. as such, enhanced environmental cleaning for all medical equipment or prohibiting communal use is recommended. presymptomatic sars-cov-2 infections and transmission in a skilled nursing facility air, surface environmental, and personal protective equipment contamination by severe acute respiratory syndrome coronavirus 2 (sars-cov-2) from a symptomatic patient stability of sars-cov-2 in different environmental conditions.the lancet microbe an international definition for "nursing home surface sampling of oronavirus disease c vid-1 : a practical "how to" protocol for health care and public health professionals. world health organization guidelines for environmental infection control in health-care facilities: recommendations of cdc and the healthcare infection control practices advisory committee (hicpac) predicting infectious sars-cov-2 from diagnostic samples key: cord-270909-wb7mwklo authors: cheng, vincent c.c.; wong, shuk-ching; chuang, vivien w.m.; so, simon y.c.; chen, jonathan h.k.; sridhar, siddharth; to, kelvin k.w.; chan, jasper f.w.; hung, ivan f.n.; ho, pak-leung; yuen, kwok-yung title: absence of nosocomial transmission of coronavirus disease 2019 (covid-19) due to sars-cov-2 in the pre-pandemic phase in hong kong date: 2020-05-24 journal: am j infect control doi: 10.1016/j.ajic.2020.05.018 sha: doc_id: 270909 cord_uid: wb7mwklo background: to describe the infection control strategy to achieve zero nosocomial transmission of symptomatic coronavirus disease (covid-19) due to sars-cov-2 during the pre-pandemic phase (the first 72 days after announcement of pneumonia cases in wuhan) in hong kong. methods: administrative support with the aim of zero nosocomial transmission by reducing elective clinical services, decanting wards, mobilizing isolation facilities, providing adequate personal protective equipment, coordinating laboratory network for rapid molecular diagnosis under 4-tier active surveillance for hospitalizedand out-patients, and organizing staff forum and training was implemented under the framework of preparedness plan in hospital authority. the trend of sars-cov-2 in the first 72 days was compared with that of sars-cov 2003. results: up to day 72 of the epidemic, 130 (0.40%) of 32,443 patients being screened confirmed to have sars-cov-2 by rt-pcr. compared with sars outbreak in 2003, the sars-cov-2 case load constituted 8.9% (130 sars-cov-2/1458 sars-cov) of sars-cov infected cases at day 72 of the outbreak. the incidences of nosocomial acquisition of sars-cov per-1,000-sars-patient-day and per-100-sars-patient-admission were 7.9 and 16.9 respectively, which were significantly higher than the corresponding incidences of sars-cov-2 (zero infection, p<0.001). conclusion: administrative support to infection control could minimize the risk of nosocomial transmission of sars-cov-2. pandemic infection of a coronavirus disease 2019 (covid-19) due to severe acute respiratory syndrome-associated coronavirus-2 (sars-cov-2) was declared by world health organization (who) on 11 march 2020, which is 72 days after announcement of a cluster of patients with community acquired pneumonia in wuhan, hubei province by national health commission of the people's republic of china (nhcprc), on 31 december 2019 (day 1) [1] . on day 72, the covid-19 had already spread to 113 countries or territories in five continents, resulting in 118,319 confirmed cases all over the world [2] . while the epidemic of covid-19 is slowing down in china, there is active community transmission in europe and north america, resulting in 30% of disease burden is outside china [2] . overwhelming number of covid-19 infections could not only paralyze the healthcare system, but more importantly, result in nosocomial outbreak, associated with increased morbidity and mortality of the hospitalized patients and healthcare workers (hcws). up to 24 february 2020 (day 56), nhcprc reported that 3,387 healthcare workers were infected with covid-19, resulting in 22 (0.6%) deaths [3] . this has exceeded the number of hcws death due sars in mainland china after 6 months in 2003 [4] . in hong kong, eight hcws succumbed as a result of nosocomial acquisition of sars-cov [5] . the top priority of our pandemic preparedness is to achieve zero covid-19 infection among hcws in hong kong. here, we report our infection control strategy and epidemiology of sars-cov-2 in the first 72 days (from the official announcement of pneumonia by nhcprc to the declaration of pandemic infection by who), using the historical data on the epidemiology of sars-cov in hong kong for comparison. after the outbreak of sars-cov in 2003, a total of 1755 persons were infected and 299 persons (17.0%) died [6] . of 386 healthcare workers (hcws) infected with sars-cov in hong kong, 8 of them (2.2%) succumbed. six hcws (2 doctors, 1 nurse, and 3 healthcare assistants) of 8 were the employee of hospital authority, the governing body of all 43 public hospitals, divided into 7 cluster-networks, responsible for 90% of inpatient service in hong kong. a "select committee to inquire into the handling of the severe acute respiratory syndrome outbreak by the government and the hospital authority" was established by the legislative council of the hong kong special administrative region, china to in order to examine the performance and accountability of the government and hospital authority and their officers at policymaking and management levels [7] . the report includes temporal sequence of events and daily statistics on sars patients with breakdown by healthcare workers and patients. the information is retrieved for analyzing the epidemiology of sars in 2003 [8] . when a novel coronavirus disease, known as covid-19 due to sars-cov-2 emerged 17 years later, hospital authority immediately activated our response plan to combat the epidemic and to prevent nosocomial transmission and outbreaks of sars-cov-2. the clinical perspective of infection control measures was reported recently [9] . the epidemiology of sars-cov-2 until 11 march 2020 (at day 72 after the official announcement of a cluster of pneumonia of unknown etiology in wuhan, hubei province, by nhcprc in hong kong) was analyzed. this is also the date when who declared the covid-19 pandemic. our results were compared with the epidemiological data of sars-cov at day 72 (11 april 2003) after the official announcement of atypical pneumonia in guangdong province, china on 11 february 2003. in addition, we also compared the epidemiology of sars-cov-2 in hong kong with hubei province, china, which is the most severe affected region by sars-cov-2, and the other countries or areas with uncontrolled local transmission at day 72, including republic of korea, islamic republic of iran, and italy, using the publicly accessible information from the who website [10] . after the sars outbreak in 2003, a preparedness plan for emerging infectious diseases, including pandemic influenza and middle east respiratory syndrome-associated coronavirus, was formulated under the governance of hospital authority. the preparedness plan to combat against sars-cov-2 is basically referring to the framework of these plans. according to the risk assessment, the response levels can be categorized into alert level, serious response level 1 (s1), serious response level 2 (s2), and emergency response level [11] . the command structure depends on the different response levels ( figure 1 ). in the alert and s1 level, the response plan is coordinated by ad hoc central committee on infectious disease and emergency responses (ad hoc ccider). in the s2 and emergency response level, the governance will be under the command of central command committee, which is chaired by chief executive of hospital authority, or emergency executive committee, which is chaired by chairman of hospital authority. the response measures at each response level comprises of a series of action, including active surveillance and electronic notification, laboratory network for rapid molecular diagnostic, infection control measures, provision of essential medical services, facility management in the hospital, human resources and staff deployment, staff training, research, and communication. contact tracing for potential secondary cases was performed to investigate for any possible nosocomial infection as reported previously [12, 13] . clinical specimens including nasopharyngeal aspirates, nasopharyngeal swabs, throat swab, saliva, sputum, endotracheal aspirates, or bronchoalveolar lavage were subjected to nucleic acid extraction by the emag extraction system (biomérieux, marcy-l'étoile france) as previously described [9, 11] . the presence of the sars-cov-2 rna in the specimens was first determined by the lightmix modular sebeccov e-gene commercial kit (tib molbiol, berlin, germany) and further confirmed by another in-house real-time rt-pcr assay targeting the sars-cov-2 rna-dependent rna polymerase/helicase gene [14] . the fisher's exact test was used to compare independent categorical variables between groups. all reported p values were two-sided. a p value of <0.05 was considered statistically significant. computation was performed using the spss version 15.0 for windows. up to 11 march 2020 (day 72 after the official announcement of a cluster of pneumonia of unknown etiology in wuhan, hubei province, a total of 130 cases of sars-cov-2 infection were confirmed in hong kong, while the first 42 patients were reported previously [9] . with these additional cases, there were 63 males and 67 hcws were infected with sars. 293 (75.9%) of them were investigated for nosocomial acquisition of sars-cov in 8 acute hospitals [15] . the incidences of nosocomial acquisition of sars-cov per 1,000 sars-patient-day and per 100 sars-patient-admission were 7.9 and 16.9 respectively, which were significantly higher than the corresponding incidences of nosocomial acquisition of sars-cov-2 (p<0.001). in the first 72 days, the incidence of sars-cov-2 in hong kong was 0.16 per 10,000 populations, which was lower than china (hubei province), europe (italy), asia (republic of korea, and singapore), and middle east (iran) ( table 1) . upon receiving the official announcement of a cluster of pneumonia of unknown etiology in wuhan, hubei province, on 31 december 2020 (day 1), the infection control responses were stepped up by hospital authority according to the rapidly evolving epidemiology in hong kong [9] . the level of response towards emerging infectious disease was directly elevated from alert to s2 on day 5. ad hoc ccider was regularly held among infection control professionals in 7 clusternetworks and senior management team in the head office of hospital authority infection of healthcare workers due to occupational exposure to infectious diseases is always a great challenge to hospital administration and infection control professionals. sporadic cases of occupation related infection among hcws due to various infectious diseases such as mycobacterium tuberculosis, hepatitis b virus, and hepatitis c virus were occasionally reported [16] . however, the impact of sars transmission among hcws was unprecedentedly high. according to who, hcws accounted for 1,707 (21%) of 8,098 cases of sars patients in 2003 [6] . it produced a significant psychosocial effects and long-term psychological effects on hcws [17] . therefore, when the covd-19 emerged, it is important to maximize our administrative resources and infection control measures to protect our hcws, which is particularly relevant in hong kong as we had 8 hcws died in 2003 as a result of nosocomial acquisition of sars-cov [5, 18] . administrative support to infection control is important to prevent nosocomial outbreak but it is not well studied in recent years [19] . however, suboptimal administrative support was attributed to the prolonged outbreak of carbapenemaseproducing enterobacteriaceae in a tertiary care hospital in france [20] , as well as the major outbreak of sars in hong kong [7] . therefore, the command structure for serially updated along with the evolving epidemic of covid-19 [9] . with the support of hospital administration, the infrastructure of hospitals was improved from the period of sars-cov to sars-cov-2 by the provision of 1400 aiirs in hong kong. early isolation of patients with sars-cov and their close contacts was found to be effective in termination of chain of transmission [5, 18] when the viral load sars was peaked at day 10 after symptoms onset [5] . for sars-cov-2, high viral load was detected soon after onset of symptoms onset [21] . a the evolving criteria of active surveillance was reported [9] . b aami level 1 isolation gown is used when small amounts of fluid exposure is anticipated. aami level 3 isolation gown can be considered when splashing is anticipated. alternatively, a waterproof apron on top of the aami level 1 isolation gown is also acceptable (with effect from 19 february 2020, day 51) c the fourth tier enhanced laboratory surveillance was updated since 20 february 2020 (day 52). the centre for health protection closely monitors cluster of pneumonia cases on mainland. press release of the department of health accessed 16 world health organization exploring the reasons for healthcare workers infected with novel coronavirus disease 2019 (covid-19) in china list of medical professionals who died during the sars outbreak severe acute respiratory syndrome coronavirus as an agent of emerging and reemerging infection sars cases with onset of illness from 1 report of the select committee to inquire into the handling of the severe acute respiratory syndrome outbreak by the government and the hospital authority daily statistics on sars patients with breakdown by healthcare workers, amoy gardens residents and others escalating infection control response to the rapidly evolving epidemiology of the coronavirus disease 2019 (covid-19) due to sars-cov-2 in hong kong coronavirus disease (covid-2019) situation reports preparedness and proactive infection control measures against the emerging novel coronavirus in china prevention of nosocomial transmission of swine-origin pandemic influenza virus a/h1n1 by infection control bundle infection control preparedness for human infection with influenza a h7n9 in hong kong improved molecular diagnosis of covid-19 by the novel, highly sensitive and specific covid-19-rdrp/hel real-time reverse transcription-polymerase chain reaction assay validated in vitro and with clinical specimens evidence/documents provided by the administration and related persons for the select committee to inquire into the handling of the severe acute respiratory syndrome outbreak by the government and the hospital authority infectious diseases in healthcare workers -an analysis of the standardised data set of a german compensation board long-term psychological and occupational effects of providing hospital healthcare during sars outbreak clinical management and infection control of sars: lessons learned the role of the hospital administrator in the control of nosocomial infections prolonged delay for controlling kpc-2-producing klebsiella pneumoniae outbreak: the role of clinical management temporal profiles of viral load in posterior oropharyngeal saliva samples and serum antibody responses during infection by sars-cov-2: an observatinoa cohort study the lessons of sars in hong kong sars and the removal of personal protective equipment hospitalized patients with 2019 novel coronavirus-infected pneumonia in wuhan, china center for diagnosis and treatment of infectious diseases, the ministry of education of china. all authors report no conflicts of interest relevant to this article. key: cord-273531-q9ah287w authors: li, yang; duan, guangfeng; xiong, linping title: characteristics of covid-19 near china's epidemic center date: 2020-06-26 journal: am j infect control doi: 10.1016/j.ajic.2020.06.191 sha: doc_id: 273531 cord_uid: q9ah287w background: this study described and analyzed the age, gender, infection sources, and timing characteristics of the 416 confirmed cases in two cities near the center of china's covid-19 outbreak. methods: this study used publicly available data to examine gender, age, source of infection, date returned from hubei, date of disease onset, date of first medical visit, date of final diagnosis, and date of recovery of covid-19 cases. results: public-use data revealed similar risks of infection by age and that the numbers of new and final diagnoses of confirmed cases first increased, peaked at about two weeks, and then gradually decreased. the main sources of infection were firsthand or secondhand exposure in hubei province and contact with confirmed cases, which mostly involved contact with infected household members. the mean periods from disease onset to first medical visit, first visit to final diagnosis, and final diagnosis to recovery were 4.44, 3.18, and 13.42 days, respectively. conclusions: the results suggest that the measures taken to control the rate of infection were effective. prevention and control efforts should respond as quickly as possible, isolate and control activities of individuals leaving infected areas, and restrict household contact transmission. the first novel coronavirus pneumonia (covid19) case was identified in wuhan, hubei province, china, on december 12, 2019, after which the disease gradually spread. 1 the emergence of the covid-19 epidemic coincided with the traditional chinese spring festival when most migrant workers return to their hometowns to celebrate. covid-19's novel infection presented few obvious upper respiratory symptoms (such as nasal discharge, sneezing, or sore throat), indicating the virus mainly was infecting the lower respiratory tract, 2,3 and most patients' first symptom was fever. the mode of transmission might have been by droplets, close contact, aerosol, mother-infant, or fecal-mouth transfer. during the incubation period, patients could transmit the virus to other humans. [4] [5] [6] [7] [8] [9] [10] as of february 22, 2020, 29 countries had reported confirmed cases of covid-19, of which china reported 76,936 confirmed cases, 22,888 recovery cases, and 2,442 deaths. 11, 12 according to the research reports, covid-19 is highly infectious, 13 and the large-scale population migration associated with the spring festival exacerbated the spread of the disease to outlying areas. xinyang city is in southern henan province, china, on the northern border of hubei province, and fuyang city is in northwest anhui province, adjacent to xinyang city. xinyang and fuyang are typical labor exporting cities near the epidemic's center. 14, 15 this study investigated aspects of the covid-19 transmission regarding xinyang and fuyang, described its characteristics, and evaluated the prevention and control measures. china's data on covid-19 are gathered based on its classification as a class b infectious disease. class b infectious diseases are considered mandatory notifiable diseases; all new cases must immediately be reported using the national infectious diseases monitoring information system database. to prevent rapid spread of the disease, the municipal health departments publicized information about the confirmed cases on the governments' websites, including personal information, personnel exposure, and the disease trajectory. we downloaded the case information from the target cities' health commission websites and transformed it into numerical data. the variables used in the analysis were: gender, age, source of infection, date returned from hubei, date of disease onset, date of first medical visit, date of final diagnosis, and date of recovery. as of february 22, 2020, 416 cases of effective data were collected in the two cities 16,17 : 270 cases in xinyang and 146 cases in fuyang. the sources of infection were: (1) firsthand or secondhand contact with hubei ("hubei exposure"), (2) "confirmed case contact," (3) "non-hubei returnee exposure," and (4) "others." "hubei exposure" comprised confirmed cases of individuals who had recently left hubei province or had not recently left hubei but had been in contact with asymptomatic individuals who had been in hubei province. "confirmed case contact" refers to infected individuals who had not left their residential areas and they had been in close contact with individuals who were confirmed cases. "non-hubei returnee exposure" refers to individuals who had recently returned to xinyang or fuyang from non-hubei provinces. in this study, a "returnee" was an individual who had returned to xinyang or fuyang from some other location, and "non-returnee" referred to an individual who had not left xinyang or fuyang. the age, gender, trajectory, and rates of infection distributions of the 416 confirmed cases in xinyang and fuyang were analyzed. the distribution of confirmed cases in households was analyzed to describe the extent of covid-19 clustered within household units. using the data on timing of disease onset and final diagnosis, the covid-19 development over time was investigated. regarding the disease trajectory (confirmed cases), four temporal stages were identified: (1) arrival → disease onset, (2) disease onset → first medical visit, (3) first medical visit → final diagnosis, and (4) final diagnosis → recovery. the mean periods of each stage were described and analyzed. ibm spss 22.0 was used for data analysis. as of february 22, 2020, 429 cases had been confirmed in xinyang and fuyang. in xinyang, 184 of the 274 cases were in recovery (67.15%), and two had died (0.73% fatality rate); in fuyang, 99 of the 155 cases were in recovery (63.87%), and no deaths were reported. thus, on that date, there were 88 and 56 ongoing cases in xinyang and fuyang, respectively. however, 13 cases were not included due to incomplete information. among the confirmed cases with complete effective data (n=416), 236 were male (56.73%) and 180 were female (43.27%). the proportional age distribution was zero-18 years old (5.05%), 19-59 years old (78.84%), and 60 years or older (16.11%). the proportion of confirmed cases aged 19-59 years in the returnee group was higher than among the non-returnees, and the proportions of confirmed cases aged zero-18 and aged 60 or older among the non-returnees were higher than among the returnees. table 1 presents the distributions regarding age, gender, source of infection, and within-household transmission and figure 1 illustrates the disease trajectory between onset and final diagnosis from january 11, 2020, through february 22, 2020, and the disease trajectory from january 23, 2020, through february 22, 2020, by source of infection. figure 1a illustrates that the first day of disease onset in the two cities was january 11, 2020, after which the number of confirmed cases gradually increased. the disease onset peak was january 25 through january 30 and then the number of newly confirmed cases gradually decreased. the first final diagnosis was on january 23, 2020, the numbers of final diagnoses gradually increased, they peaked january 31 through february 5, and they gradually decreased from that date. the peak of the final diagnoses was about six days after the peak of disease onset. hubei exposure was the source of 213 (51.20%) confirmed cases, 108 (25.96%) cases were confirmed case contacts, non-hubei returnee exposure accounted for 32 (7.69%) cases, and there were 63 (15.14%) cases due to other sources. figure 1b shows that the main source of infection before february 7 was hubei exposure, and, after february 7, the main source of infection was confirmed case contact. regarding within-household infection, 51 households (with 130 confirmed cases) experienced within-household transmission based on multiple infected household members (table 1) . of them, 33 households had two, 13 households had three, two households had four, one household had five, and two households had six infected household members (64.71%, 25.49%, 3.92%, 1.96%, and 3.92% of the households with more than one infected household member, respectively). the mean number of people infected in the households with more than one infected member was 2.55. returnees. the period between date of first visit and date of final diagnosis was slightly longer for non-returnees than returnees, and the period between date of final diagnosis and date of recovery was slightly longer for returnees than non-returnees. numbers less than zero mean that some confirmed cases did not present symptoms at the time of first medical visit. among the returnees, the proportion of confirmed cases aged 19-59 years was 87.37%, whereas the proportion of those aged 60 years or older and 0-18 years was just 12.64%. in comparison to the returnees, the proportion of non-returnees aged 19-59 years was 16.28% higher and the proportion of those aged 60 or older was 13.38% lower. the returnees' male to female sex ratio was 1.64:1, and the male to female sex ratio among non-returnees was 1.08:1. these results might reflect the fact that migrant workers are most likely to be males aged years, which means that there were relatively higher proportional representations of females and older people among the non-returnees. moreover, this finding indicates that people of all ages are susceptible to covid-19. the numbers of final diagnoses of confirmed cases peaked within 14 days of onset and then gradually decreased until february 22 when just one case was diagnosed. this finding demonstrates that the spread of the virus had effectively been controlled through various measures, such as isolating exposed people, reducing public gatherings, increasing screenings for fever, and widespread public dissemination of prevention and control information. this study's analysis revealed that the main source of confirmed cases was hubei exposure or confirmed case contact. during the first half of the outbreak period, hubei exposure was the likeliest source and, during the second half of the outbreak period, confirmed case contact was the likeliest source of infection. previous studies have found that close contact with infected individuals tended to carry a high risk of infection. 18, 19 the present study found that, of the confirmed cases whose source of infection was "confirmed case contact," 72.22% were via household contact with one or more confirmed cases. 25 studies have shown that the number of infected cases was significantly reduced by controlling the city's traffic, closing entertainment venues, and banning public gathering. implementing these measures can limit the progression of the epidemic. 26 by further controlling within-household contact with infected people and the size of public gatherings, incidence might be further decreased. the key to controlling infectious diseases is early detection, reporting, isolation, and treatment. we found that the mean period from date of return to the study area and date of disease onset was 6.69 days (range -7 1 -33). twenty confirmed cases among the returnees (10.1%) had symptoms before they arrived in xinyang or fuyang, suggesting that one of the first steps to take should be to assertively control of workers' abilities to return home which, in the early stage, might slow the rate of infection. the mean period from date of disease onset to first medical visit was about 4.44 days (range: -3 2 -21). two cases did not have symptoms at the time of first medical treatment (screening). li et al. found that the mean interval between date of disease onset and date of first visit was 5.8 days (cases with onset before january 1, 2020) or 4.6 days (onset from january 1 through january 11). 27 we found a slightly shorter period, implying that public awareness of covid-19 and medical treatment had gradually improved and people were increasingly likely to seek treatment. moreover, the mean period between date of disease onset and date of first visit 1 numbers less than zero indicate that some confirmed cases had symptoms reflecting disease onset before they returned home. 2 the negative number indicates that some cases did not present symptoms at the time of first medical treatment. among non-returnees was slightly longer than among returnees, indicating that quarantine and isolation measures were slightly stronger for returnees than non-returnees. we found that the mean period between date of first visit and date of final diagnosis was 3.18 days, suggesting that the efficiency of early detection measures needed improvement. in addition, the mean period between date of final diagnosis and date of recovery was about 13.42 days (range: 5-25). the mean hospital stay was 10 days in a previous study, 28 but it was slightly longer in our study. effective responses to covid-19 for prevention and control required implementation of governmental measures, which apparently controlled the rate of infection in xinyang and fuyang, which are cities with significant flows of migrant workers to and from hubei province. the key to controlling the rate of infection via returnees is to act as quickly as possible, focus on isolating and controlling returnees' mobility, and decreasing close within-household contact between infected and non-infected household members. if these measures were implemented as a preemptive first step, the rate of infection would further be reduced. the funder had no role in the study's design, data collection, analysis, the decision to publish epidemiology working group for ncip epidemic response. an update on the epidemiological characteristics of novel coronavirus pneumonia (covid-19) clinical features of patients infected with 2019 novel coronavirus in wuhan a familial cluster of pneumonia associated with the 2019 novel coronavirus indicating person-to-person transmission: a study of a family cluster first case of 2019 novel coronavirus in the united states national health commission of the people's republic of china. what is fecal-oral transmission? national health commission of the people's republic of china the state council information office of the people's republic of china. press conference of the joint prevention and control of the state council a 30-hour old infant in wuhan diagnosed and mother-to-child infection suspected clinical analysis of 10 neonates born to mothers with 2019-ncov pneumonia world health organization epidemiology working group for ncip epidemic response. the epidemiological characteristics of an outbreak of 2019 novel coronavirus diseases (covid-19) in china the investigation and research on fuyang's off farm workers national health commission, ministry of human resources and social security, ministry of finance. measures to improve working conditions of and care for physical and mental health of healthcare workers clinical characteristics of 138 hospitalized patients with novel coronavirus-infected pneumonia in wuhan, china henan provincial people's government a new coronavirus associated with human respiratory disease in china the novel coronavirus originating in wuhan, china: challenges for global health governance reduce large-scale gathering activities in wuhan an investigation of transmission control measures during the first 50 days of the covid-19 epidemic in china early transmission dynamics in wuhan, china, of novel coronavirus-infected pneumonia. the new england journal of medicine 2020 the state council information office of the people's republic of china. press conference of the joint prevention and control of the state council we would like to thank editage (www.editage.cn) for english language editing. the authors declare that they have no competing interests. key: cord-009114-mdlthnnp authors: subhash, shobha s.; baracco, gio; fennelly, kevin p.; hodgson, michael; radonovich, lewis j. title: isolation anterooms: important components of airborne infection control date: 2012-10-02 journal: am j infect control doi: 10.1016/j.ajic.2012.06.004 sha: doc_id: 9114 cord_uid: mdlthnnp nan comprehensive airborne infection control systems in health care settings encompass engineering controls, administrative controls, work practice controls, and personal protective equipment. no one of these elements is failure-proof but a redundancy of controls provides the most beneficial strategy. the centers for disease control and prevention recommends administrative measures, respiratory protection, and engineering (or environmental) controls for preventing the transmission of tuberculosis, the prototypical airborne infection, in health care settings. 1 in its "hierarchy of controls" to deal with workplace hazards, the occupational safety and health administration recommends engineering measures be prioritized above others. 2 however, the health care environment differs from other industries in that the source and nature of the inhalation hazard (eg, infectious aerosols) is usually not immediately defined. hence, a major goal of administrative control measures in health care settings is to place potentially infectious patients in appropriate environments where engineering controls and personal respiratory protection can be implemented. engineering controls support the implementation of permanent changes that are independent of human behavior and most cost effective. 2 airborne infection isolation rooms (aiirs), and the anterooms adjacent to aiirs, clearly fall in the category of engineering controls. despite their importance, guidance on the construction of anterooms is less than clear. we provide arguments in support of building anterooms alongside aiirs. we also review the guidance by various organizations on this topic and urge that the guidelines be made firmer in support of the construction of anterooms for aiirs. anterooms provide a permanent fixture to prevent or minimize escape of contaminated air from aiirs when the doors are opened and closed. if used properly they can buffer an aiir from pressure fluctuations in the corridor. 1 anterooms serve as an additional protective barrier when there is an unintentional entry of personnel without adequate personal respiratory protection into an aiir. finally, they serve as a dedicated location for health care personnel to don and doff equipment, thus eliminating unnecessary traffic into an aiir, and also giving engineers the flexibility to convert negative-pressure rooms to mixed isolation rooms when necessary. aiirs are used to house patients with respiratory infections such as tuberculosis, measles, varicella, and other diseases transmitted by the airborne route. aiirs are maintained at a negative pressure relative to their surroundings so that air flows into the room and not in the opposite direction, theoretically preventing escape of infectious aerosols from the aiir. unfortunately, these isolation rooms are not always maintained at a negative pressure. as reported by several studies, aiirs intermittently develop positive or neutral ventilation pressures. [3] [4] [5] [6] one of the most common reasons cited as responsible for loss of pressure differential in isolation rooms is the opening and closing of doors, which happens routinely. 7, 8 simply opening and closing of doors may move tracer gases and particles, surrogates for infectious aerosols, out of patient rooms into the adjacent hallways. [8] [9] [10] even with a negative pressure differential, airflow across open doorways can be counteracted by the turbulence routinely created by the movement of doors and people. such bidirectional airflows have been shown in laboratory studies to depend on temperature, air density, velocity of dooropening, and the angle to which the door is opened. 11, 12 a demonstration study conducted in a fully operational health care setting evaluated an aiir's performance while a human subject made routine movements. the presence of an anteroom in this setting reduced the net migration of particles from the isolation room into the corridor. 8 another study demonstrated that air exchange from an aiir to the surrounding areas often occurs during routine entry or exit, concluding that an anteroom enhances containment. 9 further, spaces equipped with anterooms have been shown to more effectively maintain a negative pressure differential than spaces without anterooms. 13 however, critics of anterooms cite a lack of clinical evidence on their effectiveness. there are no published clinical or epidemiologic studies conclusively showing that anterooms diminish or prevent the spread of lab-confirmed airborne infectious human illnesses. current scientific evidence in favor of anterooms is solely based on models or simulated human traffic where tracer gases and fluorescent microspheres have been used as surrogates of small infectious particles. more studies on aiir containment efficacy in realistic hospital environments, with and without anterooms, would be the most ideal. unfortunately, studies requiring realistic clinical data, which might be more convincing, are challenging and expensive. many of these studies are ethically questionable because they call for exposing human beings to different standards of protection in the presence of human pathogens. but still, "absence of evidence is not evidence of absence." 14 the general perceived notion about these rooms is that they are an extra space that is of not much use. some opponents of anterooms also cite the added cost ($5,000-$20,000) required for their construction as an additional burden on already stringent budgets. on the other hand, if a facility's risk assessment has determined a need to build aiirs to protect staff and patients, it would be imprudent, perhaps even disingenuous, to build isolation rooms that are known to fall short of expectations, especially when the cost of building anterooms is modest compared with the cost of a whole facility or the cost of adverse clinical outcomes over the entire lifespan of a building. although the above arguments may be valid, the case study described below further signifies the possible role anterooms may play in hospital infection control. in a recent case in the united kingdom a 62-year old white man was hospitalized with a severe case of chickenpox that required intensive care. 12 despite aggressive treatment that drew on all available resources, the patient's pneumonia relentlessly progressed and he died of multi-organ failure. hospital staff members caring for this man followed infection control precautions carefully, including observing a policy permitting only those who were chickenpox-immune to enter his room. yet 1 nurse who worked in the same intensive care unit developed chickenpox 10 days after this patient was hospitalized. importantly, this nurse did not have a personal history of chickenpox, so he made certain to never enter the room housing the patient infected with the chickenpox virus. this nurse did acknowledge that he handed equipment to coworkers several times per day through the open doorway of the isolation room housing the patient with chickenpox. he did not wear personal protective equipment because the patient's room was equipped with negative pressure ventilation, drawing air away from the hallway into the patient's room in a fashion that should have spared this nurse any exposure. however, laboratory analyses strongly suggested nosocomial transmission, and modeling revealed that opening the patient's door may have resulted in retrograde airflow and inadvertent exposure, despite the use of negative pressure ventilation. 12 even though the room was maintained at a negative pressure differential of 3 pa, rapid door opening may have caused the pressure gradient to transiently reverse. 12 the patient room in this case did not have an anteroom. the fundamental question is, what if the aiir had been equipped with an anteroom? would an anteroom have prevented inadvertent exposures in this setting? and what if the patient had been infected with h5n1 influenza, severe acute respiratory syndrome, smallpox, or another deadly virus; would the absence of an anteroom have been acceptable? we propose that anterooms are key components of infection prevention and control and must always be considered in the design and operation of aiirs in the setting of health care delivery. there is a lack of consistency in construction guidance for aiir anterooms across various professional organizations and federal agencies. table 1 summarizes the recommendations by various us and international agencies and organizations on isolation anteroom requirements. [15] [16] [17] [18] [19] [20] negative pressure isolation rooms in both the united kingdom and some states of australia are required to have anterooms between patient aiirs and adjacent corridors, but in the united states they are not required. a recent recommendation in the uk incorporates a modified design of an isolation room called a positive pressure ventilated lobby room. 12 if anterooms are included in the design, us guidelines, similar to australian guidelines, call for isolation rooms to be maintained at a negative pressure compared with the anteroom and, in turn, the anteroom to be maintained at a net negative pressure compared with the corridor. in contrast, uk guidelines call for the anteroom referred to as "vestibule or lobby" to be positively pressurized (at 10 pa) compared with both the corridor and the isolation room, positioning the lobby to act as an air-block (ie, barrier) that prevents movement of contaminated air between the isolation room and corridor. in this case, the isolation room is maintained at a quantitatively neutral pressure with respect to the corridor, whereas the en-suite (ie, private bathroom) is negatively pressurized. this arrangement positions the lobby to serve as a barrier to particles passing in either directiondinto or out of the roomdmaking the space suitable for use as an aiir, protective environment, or aiir/ protective environment room. even though anteroom inclusion makes intuitive sense, us professional organizations do not categorically call for their inclusion in isolation room design, even when housing patients with airborne-transmissible infections. instead, us guidelines generally leave the decisions to each local facility based on their perceived need. according to the facility guidelines institute, "[an] anteroom is not required for airborne infection isolation (aii) rooms" 15 ; however, if an anteroom is part of the original design, the institute still specifies these requirements. american society of heating, refrigerating and air conditioning engineers guidance states "[an] anteroom is not required [but] some isolation rooms may be provided with a separate anteroom," 16 whereas the centers for disease control and prevention/healthcare infection control practices advisory committee guidelines state "aii rooms can be constructed either with or without an anteroom." 17 one instance when anterooms are recognized as essential by most of these organizations is when combination airborne isolation and protective environment rooms are used to house infected patients with dysfunctional immune systems. despite available evidence showing the value of anterooms, the ambiguous nature of recommendations by various agencies for inclusion of anterooms leads many decision makers to undervalue their inclusion. such decisions may be unwise and might prove costly if a highly virulent pathogen is encountereddanterooms might offer an added layer of protection. when an anteroom is provided for an aiir, airflow shall be from the corridor into the anteroom and from the anteroom into the patient room (page 65, section 2.1-8.2.2.1) the airflow pattern for a aiir/pe anteroom will either be from the anteroom to both the patient room and the corridor, or from both the patient room and the corridor into the anteroom (page 172, section 2. anteroom is not required by this standard. some isolation rooms may be provided with a separate anteroom (section 7.1, part e) if the design criteria indicate that aiir is necessary for pe patients, an anteroom should be provided. rooms with reversible airflow provisions for purpose of switching between protective environment and aiir functions shall not be permitted (section 7.1, part t) the aiir described in this standard shall be used for isolating the airborne spread of infectious diseases, such as measles, varicella, or tuberculosis (section 7.1, part u) for aiirs pressure relationship to adjacent areas must be negative and shall have a minimum of -0.01 water gauge (-2.5 pa) minimum outdoor ach is 2 and minimum total ach is 12 ( 1) airflows from anteroom, to patient room and the corridor, or 2) airflows from the patient room and the corridor, into the anteroom 3) minimum total ach is 10 ( table 2 .1-2) pressure differentials for aiirs shall be a minimum of 0.01-in water gauge (2.5 pa). air movement relationship to adjacent areas is into the room. minimum total ach is 12. minimum outdoor ach is 2 ( isolation room is known as positive pressure ventilated lobby room. it is an enhanced single room with a positive pressure ventilated entry lobby and en-suite facilities (with extract ventilation) that enables the suite to be used for both source and protective isolation without need for switchable ventilation (sections 1.6 and 2.9) isolation room pressure differential to corridor is nominally 0, ach 10 lobby/vestibule pressure differential with respect to corridor is þ10 pa, ach 63 (for bed access lobby) and ach 69 (for personnel access lobby) en-suite pressure differential to isolation room is negative, ach 10 ventilated lobby acts as barrier to contamination passing in or out of isolation room ( the emergence of drug-resistant tuberculosis and the unexpected occurrences of the severe acute respiratory syndrome epidemic and the h1n1 influenza pandemic unequivocally affirm the importance of sound airborne infection prevention and control programs. the insidious threats of another influenza pandemic, bioterrorism, or the emergence of a novel airborne virus with a high fatality rate should be sufficient to convince health care administrators to ensure their facilities are equipped with robust and redundant isolation and infection prevention capabilities. aiir anterooms may not be the single most important defense against airborne infections, but available evidence indicates they play an important role. health care facilities must adopt a precautionary approach and include anterooms in the design and planned construction of isolation rooms. we call on the different professional and regulatory agencies to revise their guidelines and firmly require anterooms for all aiirs. guidelines for preventing the transmission of mycobacterium tuberculosis in health-care settings guidance on preparing workplaces for an influenza pandemic a performance assessment of airborne infection isolation rooms an evaluation of hospital special ventilation-room pressures identification of factors that disrupt negative air pressurization of respiratory isolation rooms evaluation of exposure to tuberculosis among employees at a medical center -arizona the use of engineering measures to control airborne pathogens in hospital buildings the effect of pressure differential and care provider movement on airborne infectious isolation room containment effectiveness air volume migration from negative pressure isolation rooms during entry/exit containment testing of isolation rooms combining door swing pumping with density driven flow door-opening motion can potentially lead to a transient breakdown in negative-pressure isolation conditions: the importance of vorticity and buoyancy airflows follow-up evaluation of respiratory isolation rooms in 10 midwestern hospitals absence of evidence is not evidence of absence guidelines for design and construction of health care facilities ventilation of health care facilities (ansi/ashrae/ashe approved). ashrae standard 170 n guidelines for environmental infection control in health-care facilities guidelines for design and construction of healthcare facilities in-patient accommodation: options for choice. supplement 1. isolation facilities in acute settings. health building note 4. london [uk]: national health service victorian advisory committee on infection control. guidelines for the classification and design of isolation rooms in health care facilities key: cord-259639-j7pmb3mk authors: cadnum, jennifer l.; jencson, annette l.; livingston, scott h.; li, daniel; redmond, sarah n.; pearlmutter, basya; wilson, brigid m.; donskey, curtis j. title: evaluation of an electrostatic spray disinfectant technology for rapid decontamination of portable equipment and large open areas in the era of sars-cov-2 date: 2020-06-06 journal: am j infect control doi: 10.1016/j.ajic.2020.06.002 sha: doc_id: 259639 cord_uid: j7pmb3mk in the setting of the coronavirus disease 2019 pandemic, efficient methods are needed to decontaminate shared portable devices and large open areas such as waiting rooms. we found that wheelchairs, portable equipment, and waiting room chairs were frequently contaminated with potential pathogens. after minimal manual pre-cleaning of areas with visible soiling, application of a dilute sodium hypochlorite disinfectant using an electrostatic sprayer provided rapid and effective decontamination and eliminated the benign virus bacteriophage ms2 from inoculated surfaces. contaminated surfaces are a potential source for dissemination of many bacterial and fungal pathogens. 1 there is also increasing concern that the environment may be an underappreciated source for spread of respiratory viruses, including severe acute respiratory syndrome coronavirus 2 (sars-cov-2). [2] [3] [4] many respiratory viruses survive for hours to days on surfaces, [2] [3] [4] and respiratory virus nucleic acid has been recovered from surfaces in healthcare and community settings, including households, day care centers, airports, and schools. [4] [5] [6] [7] enhanced environmental cleaning and disinfection is therefore recommended as one component of control measures for sars-cov-2 in healthcare and community settings. 8 most cleaning and disinfection of surfaces is performed through manual application of liquid disinfectants. cleaning prior to or concordant with application of disinfectants is generally considered important to reduce bioburden that might decrease the action of the disinfectant. 1 however, in one study, organic and inorganic material recovered from hospital surfaces did not affect efficacy of sodium hypochlorite and only modestly affected efficacy of ultraviolet-c light. 9 moreover, thoroughness of manual cleaning is often inadequate, and application can be challenging and time-consuming particularly when surfaces are irregular or large open areas are being cleaned. 1 one potential strategy to improve cleaning and disinfection under these conditions might be to apply disinfectant as a spray with only minimal pre-cleaning to remove visible soil. however, relatively little information is available on this approach to cleaning and disinfection. here, we tested the effectiveness of a novel spray disinfectant technology that uses an electrostatic sprayer to apply a sporicidal disinfectant to surfaces after minimal pre-cleaning. we focused on items or areas that are challenging to manually clean and disinfect, including wheelchairs, portable equipment, and patient waiting areas. the louis stokes cleveland veterans affairs medical center is a 215-bed acute care facility. shared-use wheelchairs are present throughout the facility, and hospital transport staff are available to assist patients. the facility policy states that wheelchairs should be wiped daily with a disinfectant wipe and as needed if they become soiled and portable equipment is to be wiped by personnel after each use. waiting areas are to be cleaned daily by environmental services personnel, but cleaning of these areas is not monitored. test organisms included the non-enveloped single-stranded bacteriophage ms2 in escherichia coli. 10 c. difficile spores were prepared as previously described. 9 electrostatic sprayer device and disinfectant figure 1 shows the electrostatic sprayer device (clorox total 360 system-electrostatic sprayer, clorox, oakland, ca). the device is 1 meter tall and is moved from room to room on wheels. it is plugged into a standard electrical outlet and a hand-held nozzle is used to direct a fine mist onto surfaces. the sprayer delivers electrostatically charged droplets with an average size of 40 to 80 µm that are actively attracted to surfaces to improve thoroughness of surface coverage. the device is intended to be used with a variety of different disinfectants and sanitizers. for the current study, the disinfectant used was spore defense cleaner disinfectant (clorox) which contains 0.25% sodium hypochlorite. per the manufacturer, this relatively dilute sodium hypochlorite solution leaves only minimal residual when sprayed and is non-corrosive to common materials in healthcare settings. no protective equipment is required, but the manufacturer recommends that users wear goggles. because the spray bleach product tested has a reduced concentration of sodium hypochlorite in comparison to many other bleach products, we initially tested its efficacy for killing of c. difficile spores (american type culture collection [atcc] strain 43598) and bacteriophage ms2 in the presence of 5% fetal calf serum using aoac international official method 961.02 germicidal spray products as disinfectants. 11 based on the manufacturer's recommendations, a 5-minute exposure time was used for c. difficile spores and a 2-minute exposure time was used for ms2; the product has a 1-minute claim against vegetative bacterial pathogens and many viruses. the product was sprayed once at 6 inches from stainless steel carriers applying sufficient disinfectant to thoroughly wet the inoculated surface of the carrier for the specified exposure time. the carriers were neutralized with dey-engley neutralizer (remel products, lenexa, ks). serial dilutions were plated on selective media and cultured as previously described. 9 log 10 reductions were calculated by subtracting viable organisms recovered after exposure to the disinfectants versus deionized water controls. experiments were performed in triplicate. we examined the effectiveness of the spray application of disinfectant on wheelchairs (n=30), portable medical equipment (n=40 devices), and patient waiting area chairs (n=30). the wheelchairs and chairs in waiting areas included soft and hard surfaces. portable equipment included bladder scanners, electrocardiogram machines, pulse oximeters, workstations on wheels, and doppler ultrasounds. a commercial improved hydrogen peroxide wipe was used to clean and disinfect areas with obvious visible soiling. the spray disinfectant was then applied once to the surfaces in accordance with the manufacturer's instructions and allowed to air dry. after spraying, all surfaces remained visibly wet for 2 minutes or longer. horizontal surfaces typically remained wet for at least 5 minutes but areas at the periphery began to appear visually dry within 2 minutes, and surfaces that were curved or vertically oriented also became dry within 2 minutes. cultures were collected before spraying and after spraying and air drying. cultureswabs (becton dickinson) pre-moistened with dey-engley neutralizer were used to collect samples from the wheelchairs (composite of arm rest, seat, seat back rest, and hand grips for pushing the wheelchairs), portable equipment (composite including the controls and handles commonly touched during use), and waiting area chairs (composite of chair arm rests, seat, and seat back rest); 10 cm 2 areas were sampled using a template or one-half of the entire surface of small items such as hand grips were sampled. for c. difficile cultures, sterile gloves were donned and sterile 2x2 cm gauze pads pre-moistened with dey-engley neutralizer were used to sample the same sites. after spraying, adjacent 10 cm 2 areas were sampled or alternate halves of small items were sampled. cultures were processed for c. difficile, methicillin-resistant staphylococcus aureus (mrsa), enterococci, and gram-negative bacilli as previously described. 9 for the wheelchair evaluation, additional work was performed to assess ability to eradicate inoculated viruses and to assess the time required for the spray application versus manual cleaning. for 3 of the wheelchairs, 10 6 plaque-forming units (pfu) of bacteriophage ms2 was inoculated and spread to cover 1 cm 2 areas of the seat, seat back rest, arm rest, and hand grip and allowed to air dry before the spray disinfectant was applied; 3 control wheelchairs were inoculated concurrently but not treated with disinfectant application. the personnel spraying the disinfectant were blinded to the location where the ms2 was applied. cultures of swabs and gauze pads for bacteriophage ms2 were processed as previously described. 10 the time required to apply the spray disinfectant was measured in comparison to the time required for research personnel to manually apply the same disinfectant to thoroughly cover the surfaces on the body of the wheelchair. fisher's exact test was used to compare the percentages of contamination of the wheelchairs, portable equipment, and waiting area chairs with a composite of any of the pathogens cultured. all analyses were performed using r version 3.5.1 statistical software (the r foundation for statistical computing, vienna, austria). on steel disks, the sodium hypochlorite spray reduced c. difficile spores by >6.0 log 10 colony-forming units (cfu) with a 5-minute contact time and bacteriophage ms2 by >6.0 log 10 pfu with a 2-minute contact time. as shown in figure 2 , contamination with 1 or more of the potential pathogens was present on 30% or more of surfaces cultured in waiting rooms and on portable equipment and wheelchairs. however, areas of visible soiling requiring pre-cleaning were uncommon (3 of 30, 10% wheelchairs; 2 of 40, 5% portable devices; 0 of 30 waiting room chairs). there was a significant reduction in contamination for each site after application of the spray disinfectant (p<0.01 for each comparison). c. difficile contamination was reduced but not eliminated for each of the sites, whereas the other bacteria were eliminated except for 1 isolate of gram-negative bacilli recovered after spraying a wheelchair. approximately 5 minutes was required to complete spraying of a waiting room area with 15 to 20 chairs. for the 3 wheelchairs inoculated with bacteriophage ms2, all 12 sites (4 per wheelchair) were negative for ms2 after application of the spray disinfectant whereas 4 log 10 pfu was recovered from inoculated but untreated wheelchairs. the amount of time required to apply the spray disinfectant to a wheelchair was 20 seconds, whereas manual disinfection required 84 seconds. there was minimal to no visible residue after spraying the product. eight environmental services personnel trialed the device and all expressed positive opinions regarding its use for devices such as wheelchairs and waiting areas. in the setting of the coronavirus disease 2019 (covid-19) pandemic, there has been increasing attention to the need for improved decontamination of portable devices and large open areas such as waiting rooms. television and online reports suggest that spray disinfectants are commonly being used despite limited information on their efficacy. in the current study, we found that wheelchairs, portable equipment, and waiting room chairs were frequently contaminated with potential pathogens including c. difficile spores. application of a dilute sodium hypochlorite disinfectant using an electrostatic sprayer provided a rapid and effective means to reduce bacterial contamination on these surfaces and to eliminate an inoculated bacteriophage. as noted previously, the electrostatic sprayer can be used with a variety of different disinfectant and sanitizers. the dilute sodium hypochlorite solution applied in the current study has several advantages. there is no requirement that protective equipment be worn, but the manufacturer does recommend use of goggles during operation. the product left minimal to no residue, whereas disinfectants with higher sodium hypochlorite concentrations often leave a residue. the disinfectant has a 1-minute contact time for killing of many vegetative bacteria and respiratory viruses. one limitation of the dilute sodium hypochlorite product used in this study is that a 5minute contact time is required for c. difficile spores. on real-world surfaces, c. difficile spores were reduced but not eliminated completely after a single spray application of the disinfectant. it is likely that failure to eliminate c. difficile spores was in part related to the fact that curved or vertical surfaces typically had drying times of approximately 2 minutes. thus, in settings where c. difficile is a concern, repeated application of the dilute sodium hypochlorite product may be required to maintain 5-minutes of wet contact time. our study has some limitations. first, we assessed efficacy of the spray disinfectant against the benign bacteriophage ms2 rather than against viral pathogens. however, there is evidence that bacteriophage ms2 may have increased resistance to liquid disinfectants in comparison to enveloped respiratory viruses. 12 second, we only studied one type of disinfectant with the spray technology. third, we did not compare the efficacy and efficiency of the spray technology with alternatives such as ultraviolet-c (uv-c) light. however, uv-c light is not well-suited for irregular devices with multiple angles (eg, wheelchairs) that might result in shadowing or large open areas such as waiting rooms. 1 fourth, we did not collect information on the number of colonies of the pathogens recovered from the surfaces. finally, we did not compare the efficacy of the spray technology with manual application of disinfectant. however, we do not anticipate that the spray technology will replace manual cleaning of items and surfaces that can easily be wiped. rather, the technology will be most useful for items and areas that are not amenable to standard cleaning and disinfection. in summary, our results suggest that application of a dilute sodium hypochlorite disinfectant using an electrostatic sprayer could provide rapid and effective decontamination of portable equipment and large open areas. additional studies are needed to evaluate the utility of the spray technology in community settings. for example, the technology could be useful for decontamination of areas such as airport waiting areas, classrooms, and gyms during situations such as the covid pandemic. decontamination devices in health care facilities: practical issues and emerging applications transmission of sars and mers coronaviruses and influenza virus in healthcare settings: possible role of dry surface contamination aerosol and surface stability of sars-cov-2 as compared with sars-cov-1 significance of fomites in the spread of respiratory and enteric viral disease the occurrence of influenza a virus on household and day care center fomites presence of influenza virus on touch-surfaces in kindergartens and primary schools environmental sampling for respiratory pathogens in jeddah airport during the 2013 hajj season does organic material on hospital surfaces reduce the effectiveness of hypochlorite and uv radiation for disinfection of clostridium difficile? contamination of the skin and clothing of healthcare personnel during removal of personal protective equipment aoac official method 961.02 germicidal spray products as disinfectants financial support. this work was supported by a grant from clorox and by merit review grant (1 i01 bx002944-01a1) from the department of veterans affairs to c.j.d. c.j.d has received research grants from clorox, pfizer, and pdi. all other authors report no conflicts of interest relevant to this article. key: cord-278592-67y4f9av authors: kurup, asok; chlebicki, m.p.; ling, m.l.; koh, t.h.; tan, k.y.; lee, l.c.; howe, k.b.m. title: control of a hospital-wide vancomycin-resistant enterococci outbreak date: 2008-03-24 journal: am j infect control doi: 10.1016/j.ajic.2007.06.005 sha: doc_id: 278592 cord_uid: 67y4f9av background: to analyze control measures used to eradicate a large vancomycin-resistant enterococci (vre) outbreak in a nonendemic 1600-bed tertiary care institution. methods: in mid-march 2005, vre van b was isolated from 2 clinical samples from different wards. despite such measures as screening patients sharing rooms with index cases and isolating vre patients, 43 isolates from different wards were detected by the end of march 2005. to eradicate a hospital-wide outbreak, a coordinated strategy between march and june 2005 comprised (1) formation of a vre task force, (2) hospital-wide screening, (3) isolation of carriers, (4) physical segregation of contacts, (5) surveillance of high-risk groups, (6) increased cleaning, (7) electronic tagging of vre status, and (8) education and audits. this is a retrospective study of this multipronged approach to containing vre. the adequacy of rectal swab sampling for vre was assessed in a substudy of 111 patients. the prevalence of methicillin-resistant staphylococcus aureus (mrsa)/vre co-colonization or co-infection also was determined. results: a total of 19,574 contacts were identified. between april and june 2005, 5095 patients were screened, yielding 104 vre carriers, 54 of whom (52%) were detected in the first 2 weeks of hospital-wide screening. the initial positive yield of 11.4% of persons actively screened declined to 4.2% by the end of june 2005. pulsed-field typing revealed 1 major clone and several minor clones among the 151 total vre cases, including 4 clinical cases. hospital-wide physical segregation of contacts from other patients was difficult to achieve in communal wards. co-colonization or co-infection with mrsa, which was present in 52 of 151 cases (34%) and the indefinite electronic tagging of positive vre status strained limited isolation beds. analysis of 2 fecal or rectal specimens collected 1 day apart may detect at least 83% of vre carriers. conclusion: a multipronged strategy orchestrated by a central task force curbed but could not eradicate vre. control measures were confounded by hospital infrastructure and high mrsa endemicity. although vancomycin-resistant enterococci (vre) is endemic in many settings worldwide, with the centers for disease control and prevention (cdc) reporting an increasing prevalence in united states hospitals from 0.3% in 1989 to . 25% of all isolates in 1999, its prevalence in a tertiary care institution in singapore in 2001 was , 0.01%. 1 in 2004, a localized vre outbreak in a hematology ward of singapore general hospital (sgh) involving 6 inpatients was blamed on overseas importation of the index case with breaches in infection control measures, resulting in subsequent dissemination in that ward. 2 enhanced infection control measures eradicated that outbreak. no more vre cases were seen until a large hospital-wide outbreak in march 2005, for which there was no previous local precedence. presuming background nonendemicity for vre, we embarked on an eradication strategy modeled on a previously successful effort by christiansen et al at royal perth hospital. 3 here we review our infection control approach and its shortcomings in dealing with this large outbreak. sgh has 1600 beds and offers comprehensive medical and surgical services, including acute trauma care, burn care, and solid organ and hematopoietic stem cell transplantation. single rooms (class a) comprise 11% of the beds; 4-bed rooms (class b1), 21%. the majority of the beds (68%) are in either 6-bed rooms (classes b2 and b21; 52%) or large open, communal wards with 8-or 9-bed class c cubicles (16%). the latter serve low-income populations, who receive an 80% government subsidy for medical care. for class b1 and b2 beds, patients pay 80% and 35% of the cost, respectively. patients in class a pay 100% of the costs, with no government subsidy. figure 1 shows a plan of a typical c class ward. in mid-march 2005, van b phenotype vancomycinresistant enterococcus faecium was isolated from wound samples of 2 patients from different wards. these isolates were resistant to ampicillin and had minimum inhibitory concentrations of 32 mg/ml for vancomycin and 1 to 2 mg/ml for teicoplanin. vre-positive patients were isolated, and all neighboring contacts were screened. despite this, by the end of march 2005, another 43 isolates from several different wards had been detected. subsequently, measures were applied to eradicate a hospital-wide outbreak of vre. a vre task force reporting to senior management was formed on april 3, 2005, comprising representatives from various departments, including infectious diseases, microbiology, infection control, bed management, nursing, epidemiology, information technology, operations, and corporate communications. the task force met twice daily to review various details of the outbreak and was responsible for developing policies on control measures and communicating these to all staff. the first index case was traced to an inpatient in december 2004. contacts were broadly defined as inpatients (n 5 19,574) between december 1, 2004 and april 3, 2005 . patients with high-risk acquisition for vre-like end-stage renal failure (esrf) on dialysis, those with hematologic or oncologic malignancies, those transferred from other local or overseas hospitals, or those with hospital admissions after january 1, 2005 were defined as ''unknowns.'' records of ''contacts'' and ''unknowns'' were electronically tagged to facilitate vre screening by stool or rectal swab on 2 separate occasions at least 24 hours apart. all other patients were considered ''clean'' and not screened. tagging of vre-positive status prompted admission to an isolation or cohort room on admission. rectal swabs or stool samples from patients were either directly plated onto enterococcosel agar (bd, sparks, md) containing 6 mg/ml of vancomycin (sigma, st louis, mo) or first inoculated into enterococosel broth (bd). if the inoculated broth changed color after overnight incubation, then dna was extracted and subjected to real-time polymerase chain reaction (pcr) for vana/b genes (roche diagnostics, mannheim, germany). if the pcr was positive, then the broth was subcultured onto agar containing 6 mg/ml of vancomycin. vre was identified using conventional methods 4 and confirmed by vitek 2 gp identification cards (bio-mérieux, marcy-l'etoile, france). susceptibility testing was done using vitek 2 ast p535 cards and confirmed by etest (ab biodisk, solna, sweden) if necessary. all vre isolates underwent molecular typing by pulsedfield gel electrophoresis (pfge) following the protocol specified by oon et al. 5 in instances where pcr tests were discrepant with culture results, the culture results were used to guide infection control decisions. active vre screening of all inpatients was instituted on april 3, 2005, with physical segregation of inpatients into ''clean,'' ''contact,'' and ''unknown'' categories. elective surgical admissions were cancelled on april 3 to 10 to facilitate this process. all existing inpatients on april 3 were classified as contacts and moved to predesignated cubicles, usually to 1 side of each ward, to facilitate new admissions (unknown or clean) to the other side. screening was done in phases over 2 weeks to avoid overwhelming the microbiology laboratory with specimens. at least 2 negative stool or rectal swab cultures or pcr tests collected at least 1 day apart were required before a patient could be transferred to a clean section of the ward. all vre-positive patients were isolated under strict contact precautions and screened for methicillin-resistant staphylococcus aureus (mrsa) through a single nasal swab culture where feasible. co-colonized individuals were not allowed into cohorts with those infected or colonized only with vre. the ''unknown'' category was dropped in mid-april 2005. thereafter, active surveillance for vre involving a single rectal or stool swab for vre pcr was instituted for all interhospital and overseas hospital transfers, esrf patients on dialysis, and patients undergoing renal transplantation on admission. vre-positive patients were scheduled as the last cases of clinic sessions, followed by terminal cleaning of the consultation rooms. only contacts already discharged to community dialysis centers and long-term care facilities were proactively screened as outpatients. electronic tagging of contacts and positive cases was implemented using the hospital's electronic medical record system. vre-positive tagging continued indefinitely. cleaning of isolation, cohort, and ''contact'' areas involved a 2-step decontamination process with a quarternary ammonium detergent followed by a phenolicbased disinfectant twice daily on all surfaces in the room (ie, walls, furniture, mattress, sinks, doorknob). in all other areas, only quarternary ammonium detergent cleaning was used. environmental screening was not attempted in this outbreak due to lack of resources. heightened infection control measures, especially hand hygiene, and enhanced auditing of these measures were enforced. hospital-wide education regarding vre, appropriate infection control measures, and vancomycin use involved both didactic lectures and information disseminated through the hospital's intranet. strict criteria for vancomycin use were endorsed and circulated to all clinicians. the pharmacy department audited compliance. education materials were also given to vre carriers and their caregivers. on april 1, 19,574 contacts were identified for active screening. between april and june 2005, 4934 patients were screened at least once, including 84% (912 of 1086) of inpatients on april 3. by the end of june, a total of 147 carriers and 4 clinical cases had been detected. the latter comprised 3 patients with bacteremia and 1 with wound infection, all of whom died from underlying comorbidities, which included metastatic carcinoma. pfge analysis of these isolates demonstrated the presence of a major ''outbreak'' clone pattern, a, along with smaller clones, none of which bore any relation to the 2004 hematology outbreak. all of the clinical cases bore the ''outbreak'' clone pattern a. of note, clone pattern b appeared to involve mainly esrf patients (fig. 2 ). the epidemic curve is shown in figure 2 . a total of 43 carriers were detected before the creation of the vre task force, followed by another 104 until the end of june 2005, 54 of which (52%) were detected during the first 2 weeks of the hospital-wide screening. seven carriers were detected through outpatient screening. multivariate analysis has revealed that vre carriers are likely to be found among the elderly, diabetic, and female patients with recent and prolonged hospitalization stay particularly in communal wards. 6 there was no association of vre with any specific ward. the first specimen detected 72 positive patients (65%); 2 specimens on different days detected 92 patients (83%). nineteen patients (17%) underwent screening with 2 specimens on more than 1 occasion before vre was detected. subsequent specimens were collected as part of contact screening (4 cases) or active surveillance of high-risk groups (9 cases). in 6 cases, reasons for rescreening could not be determined. the specimens were collected an average of 17.5 days (range, 1 to 43 days) after initial vre screening. the patients spent an average of 9 days (range, 1 to 33 days) in the hospital after their second negative stool test; 17 (90%) received various antibiotics for an average of 8.4 days (range, 2 to 27 days). co-colonization and/or co-infection with mrsa was present in 52 of 151 (34%) vre cases. this affected the creation of pure vre cohorts and stretched the capacity of the existing 16-bed isolation ward. consequently, the latter was extended to a 46-bed ward by temporarily displacing an adjacent colorectal ward. at the peak of the outbreak, active screening for vre revealed a positive yield of 11.4% (29 of 254) of persons actively screened. this fell to 4.2% (6 of 142) by late june 2005 (fig 2) . note, however, that the denominator (ie, the number of patients screened each week during the outbreak) was higher before week 17 due to hospital-wide screening and declined thereafter due to cessation of screening of the ''unknown'' patient category. a prevalence study involving hematology and oncology wards and medical and surgical icus yielded no vre cases. physical segregation was discontinued in early july 2005, followed by discontinuation of contact screening. the restriction of vancomycin use and active surveillance of high-risk groups continued. vre endemicity may have serious consequences in tertiary care institutions with immunocompromised patients. vre has been independently associated with increased mortality among patients with enterococcal bloodstream infections. 7 infections caused by vre also can result in increased morbidity, length of hospitalisation, and costs. the threat of vancomycin-resistant staphylococcus aureus (vrsa) will be raised if vre becomes as endemic as mrsa. an aggressive approach to controlling vre, akin to ''nipping the problem in the bud,'' requires identifying the reservoir while isolating positive patients. the numerous carriers from several different wards within 2 weeks of the outbreak suggested the existence of a large hospital-wide reservoir of vre. 8, 9 this triggered hospital-wide screening as part of a multipronged strategy to weed out carriers for isolation while maintaining surveillance of high-risk groups. in retrospect, it could be argued that we did not actually have a true nonendemic state, and that there was a transition from an initial monoclonal vre outbreak in the hematology ward in 2004 to a multiclonal, hospital-wide spread in 2005. however, no vre case was identified at any time between these 2 periods. controlling vre in a nonendemic setting has little precedence. we tried to reproduce a successful containment effort at royal perth hospital, 2 albeit with numerous conundrums. to avoid overwhelming the laboratory, hospital-wide screening of the more than 2000 stool specimens was done in phases over 2 weeks. in contrast to the 4 separate screening stool samples used by christiansen et al, 2 only 2 samples per patient were usually analyzed, which detected 83% of carriers. nineteen carriers were detected several days after they were ''cleared'' by 2 negative stool cultures; however, acquisition of vre after initial screening could not be excluded. the outbreak appeared to spare hematology, oncology, and icu patients through limited surveillance. although risks included coexisting diabetes and prolonged hospitalizations, the stay in crowded communal wards was the biggest infection control challenge. interbed spacing of , 3 feet, limited toilet facilities (fig 1) , and a low nurse-to-patient ratio were among the problems. physical segregation was artificial, and dedicating nursing teams to separate cohorts of patients was impossible. a transient attempt to improve interbed spacing by reducing the number of beds per cubicle was abruptly reversed by pressure from bed management and the high hospital occupancy rates. the cancellation of surgical electives to facilitate patient segregation movements affected costs and inconvenienced patients. to facilitate appropriate patient placement, long delays in admissions from the emergency department ensued. similar bed ''crunches'' limited ring-fencing of vulnerable patients to parent wards and forced discontinuation of the ''unknown'' category 2 weeks into the outbreak. bed management systems were stressed by the need to physically segregate patients according to the different outbreak categories while maintaining their class status. lack of resources prevented us from doing environmental screening, although this would have been useful, 10 because cleaning practices could not be supervised adequately. proactive outpatient screening also was limited. some lessons were learned. centralized planning, coordination, and dissemination of information from a multidisciplinary task force with a strong mandate from senior management were important. the experience dealing with the severe acute respiratory syndrome (sars) outbreak in 2003 allowed us to respond quickly to this new threat. coordinated outbreak control measures were introduced within hours of the first vre task force meeting. typing using pfge provided insight into the outbreak and nonoutbreak strains but was limited in its turnaround time. identifying the outbreak clone by a faster method could have prompted earlier focused strategies. the existence of a vre clone specific to esrf patients suggests the need for a coordinated national effort to study vre prevalence in community dialysis centers. given our high background mrsa endemicity, determining mrsa status before the creation of vre cohorts was imperative, as evidenced by the fact that more than 1/3 of cases were co-colonized or co-infected with mrsa although this and the indefinite tagging of vre-positive status stretched our limited isolation facilities, it certainly highlighted the need to also control endemic mrsa. educating staff unfamiliar with vre was challenging, but at least half of the staff attended more than 20 lectures held throughout the outbreak. although an audit showed a noncompliance rate of 23.4% of 260 vancomycin orders, it offered opportunities to further educate prescribers. the scale of the outbreak necessitated dissemination of information to the public through the media and other resources. although this prompted several claims for compensation from affected patients, it made it easier for the public to understand the constrained processes within the hospital during the outbreak. a multipronged strategy orchestrated by a central task force helped curb the outbreak at the expense of bed management systems, loss of revenue, and inconvenience to patients. the total cost of this strategy is still being computed. eradicating vre was hampered by our large hospital size, heterogenous patient mix with numerous inpatient movements, and communal wards. the 2006 vre incidence in sgh was 0.04 per 1000 patient-days. along with surveillance of risk groups including communal ward patients, the following measures are aimed at averting another outbreak: we thank the epidemiolgy unit of sgh for their kind assistance in providing the epidemiology data. tional nosocomial infections surveillance (nnis) system report: data summary from first outbreak of vancomycinresistant enterococcus faecium in a tertiary-care hospital in singapore eradication of a large outbreak of a single strain of vanb vancomycin-resistant enterococcus faecium at a major australian teaching hospital performance standards for antimicrobial susceptibility testing: twelfth informational supplement. wayne (pa): national committee for clinical laboratory standards gastrointestinal colonisation of vancomycin-resistant enterococcus in a singapore teaching hospital predictors of vancomycinresistant enterococcus (vre) carriage in the first major vre outbreak in singapore comparison of mortality associated with vancomycin-resistant and vancomycinsusceptible enterococcal bloodstream infections: a meta-analysis shea guideline for preventing nosocomial transmission of multidrug-resistant strains of staphylococcus aureus and enterococcus what to think if the results of the national institutes of health randomized trial of methicillin-resistant staphylococcus aureus and vancomycin-resistant enterococcus control measures are negative (and other advice to young epidemiologists): a review and an au revoir reduction in acquisition of vancomycin-resistant enterococcus after enforcement of routine environmental cleaning measures key: cord-302103-mwlgvuag authors: higgins, wayne; wainright, charles; lu, ning; carrico, ruth title: assessing hospital preparedness using an instrument based on the mass casualty disaster plan checklist: results of a statewide survey date: 2004-09-27 journal: am j infect control doi: 10.1016/j.ajic.2004.03.006 sha: doc_id: 302103 cord_uid: mwlgvuag background: hospitals would play a critical role in a weapon of mass destruction (wmd) event. the purpose of this study is to assess preparedness for mass casualty events in short-term and long-term hospitals in kentucky. methods: all short-term and long-term hospitals in kentucky were surveyed using an instrument based on the mass casualty disaster plan checklist and a brief supplemental bioterrorism preparedness questionnaire based on a checklist developed for the agency for healthcare research and quality. results: responses were received from 116 of the 118 (98%) hospitals surveyed. hospitals reported surge capacity equal to 27% of licensed beds, and virtually all respondents were engaged in planning for weapons of mass destruction events. however, advanced planning and preparation were less common. large regional differences were observed, especially in the area of pharmaceutical planning. preparedness planning in general and pharmaceutical management planning in particular were more advanced in counties participating in the metropolitan medical response system program (mmrs). conclusions: hospital mass casualty preparedness efforts were in an early stage of development at the time of this survey, and some critical capabilities, such as isolation, decontamination, and syndromic surveillance were clearly underdeveloped. preparedness planning was more advanced among hospitals located in mmrs counties. in response to the terrorist attacks of september 11, 2001 (9/11) and the release of anthrax through the mail in the following weeks, the federal government provided $135 million to the states in fiscal year 2003 through the bioterrorism hospital preparedness program. 1 states were required to assess hospital preparedness and develop regional response plans to receive the bulk of these funds. 2 in kentucky, the total allocation was approximately $1.8 million, and the kentucky department for public health contracted with the kentucky hospital association (kha) to conduct the assessment. 3 the kha established a bioterrorism task force comprising hospital executives, infection control practitioners, emergency planners, and kha staff to survey hospitals in the state. this task force approved the survey methodology and provided oversight for the study. after considering several checklist type instruments, the task force selected the mass casualty disaster plan checklist: a template for healthcare facilities, developed by the association of professionals in infection control and epidemiology (apic) and the center for the study of bioterrorism and emerging infections, 4 as the basis for the survey instrument. this paper reports findings from the kha survey. the danger of terrorism involving weapons of mass destruction (wmd) was recognized well before 9/11. the federal government increased support for preparedness in response to presidential decision directive 39, issued in 1995, and the defense against weapons of mass destruction act of 1996, which included funds to improve planning, training, and equipment for local emergency response agencies. 5, 6 the federal government also funded the metropolitan medical response system (mmrs), which supports planning, training, and equipment purchases to improve hospital and health system preparedness 6 and implemented a number of programs to strengthen the public health system. the critical role of hospitals in any wmd event is widely recognized. macintyre et al cited prompt recognition of the incident, staff and facility protection, patient decontamination and triage, medical therapy, and coordination with external emergency response and public health agencies as key elements of health care facility response plans. 7 the american hospital association (aha) offered broad recommendations for hospital and community-wide preparedness. 8 more detailed recommendations for dealing with bioterrorism were developed jointly by the apic bioterrorism task force and the centers for disease control and prevention (cdc) hospital infections program bioterrorism working group, 9 and, effective on january 1, 2001, the joint commission for the accreditation of healthcare organizations (jcaho) required hospitals to have emergency management plans based on a hazard vulnerability analysis. however, the limited research evidence available prior to 9/11 suggested that hospitals were ill prepared to respond to casualties resulting from exposure to hazardous materials or radiation. [10] [11] [12] [13] [14] [15] this study assesses the preparedness of kentucky hospitals to respond to bioterrorism and other mass casualty events. the mass casualty disaster plan checklist was modified in 2 ways to convert it into a survey instrument. first, some items on the checklist asked for a single answer to questions that contained 2 or more parts. these items were separated, unless the multiple parts were so closely related that a single response was appropriate. second, some items of specific interest to the kha task force were added (eg, respondents were asked how much their facility had spent on preparedness since 9/11). the final instrument was 14 pages long, with 252 items. in july 2002, the questionnaire along with a cover letter was mailed to chief executive officers (ceos) of all 118 short-term and long-term hospitals in kentucky. the ceos were asked to oversee completion of the survey. in practice, most ceos assigned completion of the survey to staff members responsible for emergency planning and/or infection control, and input was typically obtained from several staff members. the survey was also available on the kha web site, and a few respondents completed it electronically. in august 2002, the agency for healthcare research and quality (ahrq) released a needs survey for hospitals to use as a checklist for assessing their capacity to handle victims of bioterrorist attacks and the adequacy of their emergency plans. 16 because the ahrq instrument focused on bioterrorism, the area of greatest concern to state officials, the kha task force mailed a brief supplemental survey (3 pages, 20 questions) using items selected from the ahrq instrument in september 2002. repeated calls were made by kha staff to hospitals that did not respond to the surveys. clarification and corrections were also made via telephone. in total, the survey process extended from july 2002 to february 2003. one hundred sixteen hospitals and hospital systems (98%) responded to at least 1 survey. one hundred eight (92%) responded to both surveys; 3 responded to the first survey only, and 5 responded to the supplemental survey only. responding hospitals accounted for all but 325 of kentucky's 18,403 licensed hospital beds (98%). hospital responses were aggregated for the state as a whole and for each of 14 multicounty emergency management areas (emas). twelve of the emas had 100% response rates, and the lowest ema response rate was 86%. states were directed by the cdc to prepare regional response plans based on the assumption that resources to treat 500 casualties should be available. no guidance was provided regarding how many of the 500 casualties might require inpatient care. statewide, hospitals reported the ability to surge 4881 beds or 27% of all licensed beds in the state. one hundred thirty-two surge beds (3%) were reported by long-term hospitals. based on the assumption that 25% of casualties would require inpatient treatment, all 14 emas met the 500 casualty planning standard. however, when it was assumed that half of the casualties would require hospital admission, 6 rural emas did not have adequate surge beds. respondents reported a total of 594 isolation beds and 937 adult, 193 pediatric, and 214 neonate ventilators. only hospitals in the louisville area reported operating at full bed capacity more than 25% of the time. virtually all hospitals (99%) had disaster plans and disaster planning committees (95%). more than 9 out of 10 reported collaborative relationships with emergency medical services (96%), emergency management agencies (94%), law enforcement agencies (95%), fire departments (95%), and health departments (92%). almost all respondents (96%) reported that disaster plans were widely distributed and readily available throughout the facility. eighty-three percent reported that the board and medical staff had reviewed the plan, and 73% reported that disaster plans addressed weapons of mass destruction incidents (defined as biologic, nuclear, incendiary, chemical, explosive and/ or radiologic on the survey instrument). almost all (96%) reported conducting annual disaster exercises and conducting a formal critique of the exercise, which is shared with all key participants (90%). more detailed questions concerning planning and preparation activities revealed mixed results. the vast majority of respondents reported that emergency plans addressed basic activities, such as designating an incident commander (90%), assigning responsibility for recalling off-duty staff (91%), and specifying the location of the hospital disaster control command center (90%). however, fewer reported plans that addressed more detailed activities, such as specifying which areas to close if staffing shortages occur (26%), specifying how volunteers were to be incorporated and managed (35%), and describing how to manage vehicles and personnel that converge on the facility (12%). seventy-eight percent reported having the ability to lock down the facility, but only 56% had tested the lock down procedures. six sections of the primary survey had sufficiently high internal consistency and intercorrelation among items (cronbach's a>0.7) to serve as composite measures of the variables of interest. for these sections (general response capability, ability to handle and control external traffic flow, preparation to deal with the news media, preparation to receive casualties and victims, preparation to deal with being out of communication or cut off from resources, and preparation to manage pharmaceuticals), a single index score, ranging from 0 to 1.0, was calculated for each ema. lower scores suggest that hospitals are less prepared to respond in a particular area. table 1 displays median scores for each ema and the median score for the state as a whole. for each composite measure, there was considerable variation across emas, although, as a group, hospitals reported a reasonable level of preparedness planning in all areas except pharmaceutical management. hospitals were generally well prepared to receive casualties and conduct activities such as triage and treat, admit, or transfer multiple casualties on short notice, but pharmaceutical planning, which could be of vital importance in a bioterrorism event, was less advanced. only 43% of respondents reported that the pharmaceutical allocation plan provided for prophylaxis of caregiving staff, and even fewer reported planning for prophylaxis of first responders (34%) and caregiver's family members (20%). thirty-two percent of respondents reported participating in a community or regional pharmaceutical stockpile. thirty-eight percent reported emergency plans that addressed stockpiling antibiotics and supplies, and only 25% maintained a separate cache of antibiotics to treat staff in the event of a bioterrorist incident. higher levels of pharmaceutical planning were observed in emas 6 and 13, which include kentucky's 2 mmrs regions. most respondents reported that their medical staff members have access to information for treating victims of biologic (82%), chemical (77%), nuclear (67%), radiologic (69%), and major burn (73%) exposures. sixty-three percent reported having radiation detection instruments, but only half reported having surveillance capability is essential for detecting a covert bioterrorism event when the first indication of an attack may be patients presenting with influenzalike illness at hospital emergency departments, primary care physician practices, and clinics. 17, 18 table 2 displays surveillance related responses from both surveys. more than half (56%) of respondents had electronic database systems that track patient's presenting problems. of these, only 28% tracked influenza-like illness, and only 1 in 5 tracked increased antibiotic prescription rates. questions added to the primary survey by the kha task force asked about hospital participation in regional bioterrorism response planning and changes initiated after 9/11. half of all respondents reported participating in regional response plans. among participants, about one quarter (24%) reported regional response plans addressing quarantine, and 39% reported plans addressing patient isolation. respondents reported updating disaster plans (81%), implementing additional training (66%), and purchasing new equipment (38%) since 9/11. overall, respondents reported spending almost $1.7 million to increase preparedness in response to the terrorist attacks. when asked to identify their 3 highest priority needs if external funds became available, respondents listed almost $18.5 million in needed investments, primarily for training and equipment. the metropolitan medical response system (mmrs) of the us department of health and human services, which became operational in 1997, provides funds to major us cities to help them develop plans for responding to the health and medical consequences of a terrorist attack with chemical, biologic, or radiologic agents. 7 in fiscal year 2000, louisville-jefferson county and lexington-fayette county received mmrs contracts. to evaluate the impact of the mmrs program, responses from hospitals in jefferson and fayette counties were compared with responses from hospitals in all other counties. the louisville and lexington areas contain most of the state's large, tertiary care hospitals and both of its academic medical centers; thus, it was not surprising that hospitals in these areas reported more beds, larger pharmaceutical inventories, and more equipment, such as ventilators. they also reported greater laboratory capability to rule out potential bioterrorism agents. however, hospitals in fayette and jefferson counties evidenced superior readiness in other areas that may be attributable to the mmrs program. table 3 displays preparedness activities that were significantly more common among hospitals located in fayette and jefferson counties. pharmaceutical planning was considerably more advanced in the mmrs counties. hospitals in these counties were more likely to have dedicated decontamination facilities and to have conducted a disaster exercise using the decontamination facility. agreements with other health care facilities to accept patients were more likely to be in place, and, as expected, regional planning was more advanced in the mmrs counties. mean scores on the 6 composite measures were compared for hospitals in fayette and jefferson counties and facilities in all other counties. hospitals in the mmrs counties scored significantly higher on the measures for pharmaceutical management (p < .001) and preparation for being out of communication or cut off from resources (p < .001). the mass casualty disaster plan checklist formed the basis for a useful instrument to assess hospital preparedness for wmd events. results from the kha surveys were used to develop regional hospital preparedness plans in kentucky. large regional differences in hospital preparedness were observed across emas, with areas containing mmrs counties generally reporting more advanced levels of preparedness. overall, the results suggest that much work remains to be done. hospital wmd preparedness planning and coordination on a community or regional basis were in early stages of development at the time of this survey, and some critical hospital response capabilities, such as isolation, decontamination, and syndromic surveillance were clearly underdeveloped. these results are generally consistent with those of a national survey of 2021 short-term, nonfederal, general hospitals in metropolitan statistical areas conducted by the us general accounting office (gao) between may and september 2002. the gao found that most hospitals reported participating in basic planning and coordination activities for bioterrorism response, but many lacked the medical equipment to handle the number of patients that would likely result from a bioterrorist incident. 2 the mmrs program appears to be producing positive results as evidenced by the comparison of mmrs and non-mmrs counties in kentucky. most encouragingly, hospitals in mmrs counties reported more advanced pharmaceutical planning and preparedness, an area of critical importance in a bioterrorism event. however, the need for greater support for preparedness efforts in non-mmrs counties was evident in the large variations across emas and low scores on the composite measure of pharmaceutical planning. there are several limitations to this study. first, the results cannot be generalized nationally because only hospitals in kentucky participated. second, the 2 surveys extended over 7 months at a time when hospitals were busily engaged in preparedness activities. thus, it seems likely that early respondents continued to improve during the study period, and these improvements are not reflected in the results. however, much of the delay was caused by the need to clarify responses to questions in the supplemental survey, and the gao survey also extended over a prolonged time period (4 months). 2 in addition, repeated calls from kha staff resulted in a remarkably high response rate, although this process extended the duration of the survey. third, kentucky hospitals have continued to improve preparedness and response capabilities since this survey was completed. it is likely that hospitals are better prepared today in a number of areas, both because of increased investment and training related to bioterrorism readiness and in response to concerns raised by the outbreak of severe acute respiratory syndrome (sars). almost $1.8 million in federal funds have been provided to hospitals in the commonwealth, and some hospitals purchased decontamination equipment and ppe with these funds. however, kentucky hospitals had already spent almost $1.7 million of their own revenues to improve preparedness, and respondents identified more than $18 million in high priority needs. thus, in kentucky as elsewhere, the burden of preparing for catastrophic terrorism is largely an unfunded mandate for hospitals. finally, the finding that the mmrs program has had a favorable impact on hospital preparedness should be viewed as suggestive. the institute of medicine has recommended a comprehensive evaluation process for this program and noted several limitations of checklisttype questionnaires for evaluating complex programs, such as the mmrs. 7 overall, the surveys described above provided a valuable input to regional and state-level preparedness planning. comments from hospital ceos suggest that responding to the survey based on the mass casualty disaster plan checklist provided a useful educational experience for them and their staff, as well as helping improve emergency plans. as preparedness efforts continue, these or similar instruments could be administered periodically to assess the progress of hospital preparedness planning. statement of the american hospital association before the national committee on vital and health statistics panel on national preparedness and a national health information infrastructure report to congressional committees: hospital preparedness: most urban hospitals have emergency plans but lack certain capacities for bioterrorism response. us general accounting office mass casualty disaster plan checklist: a template for healthcare facilities national health and medical services respond to incidents of chemical and biological terrorism national defense authorization act for fiscal year 1997. p.l. 105-201, title xiv, defense against weapons of mass destruction, subtitle a, domestic preparedness section preparing for terrorism: tools for evaluating the metropolitan medical response system program weapons of mass destruction events with contaminated casualties american hospital association. hospital preparedness for mass casualties final report bioterrorism readiness plan: a template for healthcare facilities hospital response to a chemical incident: report on casualties of an ethyldichlorosilane spill hospital evacuations due to hazardous materials incidents contaminated casualties: are we prepared to receive them? hospital preparedness for hazardous materials incidents and treatment of contaminated patients hazardous materials preparedness in the emergency department hospital preparedness for victims of chemical or biological terrorism agency for healthcare research and quality domestic preparedness for events involving weapons of mass destruction use of automated ambulatory-care encounter records for detection of acute illness clusters, including potential bioterrorism events key: cord-261595-c69vfs8q authors: allegranzi, benedetta; memish, ziad a.; donaldson, liam; pittet, didier title: religion and culture: potential undercurrents influencing hand hygiene promotion in health care date: 2008-10-03 journal: am j infect control doi: 10.1016/j.ajic.2008.01.014 sha: doc_id: 261595 cord_uid: c69vfs8q background: health care–associated infections affect hundreds of millions of patients worldwide each year. the world health organization's (who) first global patient safety challenge, “clean care is safer care,” is tackling this major patient safety problem, with the promotion of hand hygiene in health care as the project's cornerstone. who guidelines on hand hygiene in healthcare have been prepared by a large group of international experts and are currently in a pilot-test phase to assess feasibility and acceptability in different health care settings worldwide. methods: an extensive literature search was conducted and experts and religious authorities were consulted to investigate religiocultural factors that may potentially influence hand hygiene promotion, offer possible solutions, and suggest areas for future research. results: religious faith and culture can strongly influence hand hygiene behavior in health care workers and potentially affect compliance with best practices. interesting data were retrieved on specific indications for hand cleansing according to the 7 main religions worldwide, interpretation of hand gestures, the concept of “visibly dirty” hands, and the use of alcohol-based hand rubs and prohibition of alcohol use by some religions. conclusions: the impact of religious faith and cultural specificities must be taken into consideration when implementing a multimodal strategy to promote hand hygiene on a global scale. health care-associated infection is a major patient safety problem worldwide, affecting hundreds of millions of patients each year. 1 hand hygiene is considered the leading measure to reduce the impact of health care-associated infections and prevent pathogen transmission in health care settings, 2,3 but compliance with hand hygiene measures remains poor overall. 4, 5 the world health organization's (who) global patient safety challenge, ''clean care is safer care,'' a core component of the who's world alliance for patient safety, 6 is dedicated to tackling the issue of health care-associated infection worldwide. 1, 7 the central strategy for achieving the goals of the challenge focuses on the development of who guidelines on hand hygiene in health care 8 and their implementation in a pilot-test phase. these guidelines consider new aspects of hand hygiene promotion, including behavioral and transcultural issues. within this framework, the present article reflects the findings of the who's task force on religious and cultural aspects of hand hygiene. the task force was created to explore the potential influence of transcultural and religious factors on attitudes toward hand hygiene practices among health care workers and to identify some possible solutions for integrating these into strategies for improving hand hygiene. research into religious and cultural factors influencing health care delivery has been conducted previously, but mostly in the field of mental health and in countries with a high influx of immigrants, where unicultural care is no longer appropriate. 9, 10 in a recent world conference on tobacco use, the role of religion in determining health beliefs and behaviors was raised and deemed a potentially strong motivating factor to promote tobacco control interventions. 11 a recent review has listed various potential positive effects of religion on health as shown by studies demonstrating its impact on disease morbidity and mortality, behavior, and lifestyle, as well as the capacity to cope with medical problems. 12 beyond these particular examples, the complex association between religion and culture and health-particularly hand hygiene practices among health care workers-remains a lightly explored, speculative area. an exhaustive literature search of the us national library of medicine's pubmed database from january 1966 to october 2007 was conducted without language restrictions. the key search terms used were ''religion,'' ''culture,'' ''hand hygiene,'' ''hand washing,'' ''hygiene,'' ''alcohol-based hand rub,'' ''buddhism,'' ''christianity,'' ''hinduism,'' ''islam,'' ''judaism,'' ''orthodox christianity,'' and ''sikhism.'' bibliographies of retrieved articles were also hand-searched for additional studies. relevant books on culture and health were consulted as well. leaders from the most important religions affiliated with the world council of churches (a fellowship of churches associated in an ecumenical movement to promote christian unity) and the muslim world league (an islamic nongovernmental organization that promotes islamic unity) were individually consulted to gather knowledge regarding the importance of hygiene, hand hygiene, and alcohol prohibition within the precepts and holy texts of their faiths. a total of 2332 articles were retrieved through the medline search. many of the articles referred to ''culture'' in the microbiological sense and had to be eliminated, together with numerous articles restricted to mental health. of the remaining articles, only 27 referred to cultural and/or religious aspects influencing health, in particular hygiene, hand hygiene practices, and alcohol prohibition according to the most important religions; these were retained for review. the literature review and consultation with religious leaders were performed by 2 of the authors (b.a. and d.p.), who identified the relevant issues to be considered and then brought these to the attention of the task force members through a formal consensus process. the task force comprised experts in infection control and behavioral theories, as well as anthropologists and psychiatrists. they met in april 2005 and were consulted by e-mail and telephone in 2006 and 2007 to finalize the article after an additional literature search. of the vast number of religious faiths worldwide, only the most widely represented were considered in this study (fig 1) . 13 for this reason, this review cannot be considered exhaustive by any means. some ethnoreligious aspects, such as practices of local, tribal, animistic, or shamanistic religions, also were evaluated. based on the literature review and the consultation of religious authorities, the most important topics identified by the task force were the importance of hand hygiene in different religions, hand gestures in different religions and cultures, the interpretation of the concept of ''visibly dirty hands,'' and the use of alcohol-based hand rubs in the light of alcohol prohibition by some religions. according to behavioral theories, 14, 15 hand cleansing patterns are most likely to be established in the first 10 years of life. this imprinting subsequently affects the attitude toward hand cleansing throughout life, particularly ''inherent hand hygiene,'' which reflects the instinctive need to remove dirt from the skin. the attitude toward hand cleansing in more specific opportunities, called ''elective hand hygiene practice,'' more frequently corresponds to the indications for hand hygiene during health care delivery. 2, 8 in some populations, both inherent and elective hand hygiene practices may be deeply influenced by cultural and religious factors, although establishing whether a strong inherent attitude toward hand hygiene directly determines an increased elective behavior has proven difficult. hand hygiene can be practiced for hygienic reasons, for ritualistic reasons during religious ceremonies, and for symbolic reasons in specific everyday life situations (table 1) . islam, judaism, and sikhism have precise rules for handwashing specified in holy texts, and this practice punctuates several crucial times of the day. in the sikh culture, hand hygiene is not only a holy act, but also an essential element of daily life. islam places great emphasis on cleanliness 10 in both its physical and spiritual aspects, and the qu'ran gives clear instructions as to how this should be carried out (table 1) . 16, 17 with the exception of the ritual sprinkling of holy water on hands before consecration of the bread and wine and the washing of hands after touching the holy oil (the latter in the catholic church), the christian faith does not include definite indications for hand cleansing. in general, the indications given by christ's example refer more to spiritual behavior, but the emphasis on this specific viewpoint does not imply that personal hygiene and body care are not important in the christian way of life. similarly, the buddhist faith has no specific indications regarding hand hygiene in daily life or during ritual occasions, apart from the hygienic act of washing hands after each meal. culture also may be an influential factor regardless of religious background. in certain african countries (eg, ghana and some other west african countries), hand hygiene is commonly practiced in specific situations of daily life according to ancient traditions; for instance, hands always must be washed before raising anything to one's lips. furthermore, it is customary to provide facilities for hand aspersion (a bowl of water with special leaves) outside the house door to welcome visitors and allow them to wash their face and hands before even inquiring of the purpose of their visit. unfortunately, the hypothesis that community behavior influences health care workers' professional behavior has been corroborated by only scanty scientific evidence. in particular, we found no data on the impact of religious norms on hand hygiene compliance in health care settings in which religion is very deep-seated. this topic merits further research from a global perspective to identify the most effective components of hand hygiene promotion in these communities. hand use and specific gestures are universal but have considerable significance in certain cultures. 18 the most common popular belief regarding the hands in african, hindu, jewish, and muslim cultures is to consider the left hand ''unclean'' and reserved solely for ''hygienic'' reasons, with the right hand used for offering, receiving, eating, and gesticulating. in the sikh culture, as in mahayana and tibetan buddhism, a specific cultural meaning is given to the habit of folding the hands together as a form of greeting, in prayer, or as a mark of respect. studies have demonstrated the importance of the role of gestures in teaching and learning, and there is certainly a potential advantage to considering this in the teaching of hand hygiene, particularly in its representation in pictorial images for different cultures. 19, 20 in multimodal strategies to promote hand hygiene, posters placed in key points in health care settings have proven to be very effective tools for reminding health care workers to cleanse their hands. 2, 8, 21 efforts to consider specific hand uses and gestures according to local customs in visual posters, including education and promotion material, may help convey the intended message more effectively. this area also merits further research. both the centers for disease control and prevention 2 and the recent who guidelines 8 recommend that health care workers wash their hands with soap and water when visibly soiled. otherwise, rubbing the hands with an alcohol-based formulation is recommended as the preferred practice for all other hand hygiene indications during patient care, because it is faster, more effective, and better tolerated by the skin. but infection control practitioners find it difficult to precisely define the meaning of ''visibly dirty'' and to provide practical examples when teaching hand hygiene. from a transcultural perspective, finding a common understanding of this term is even more difficult; for example, a spot of blood or other proteinaceous material is more difficult to see on very dark skin. furthermore, in a hot and humid climate, the need to wash the hands with fresh water also may be driven by the feeling of sticky or humid skin. according to some religions, the concept of dirt is not strictly visual and reflects a wider meaning, referring to interior and exterior purity. 22, 23 among some health care workers, such a perspective may lead to the perceived need to wash the hands with water when feeling ''impure'' and may be an obstacle to the use of alcohol-based hand rubs. the cultural issue of feeling cleaner after handwashing rather than after hand rubbing actually was raised recently during a widespread hand hygiene campaign in hong kong and may underlie the inability to sustain the excellent hand hygiene compliance attained during the recent severe acute respiratory syndrome (sars) pandemic (w.h. seto, personal communication). from a global perspective, the foregoing considerations underscore the importance of making every possible effort to consider the concept of ''visibly dirty'' in accordance with racial, cultural, and environmental factors, and to adapt it to local situations with appropriate strategies to promote hand hygiene. based on scientific evidence, the use of alcoholbased hand rubs is considered the gold standard for hand hygiene in health care. 2, 3, 8, 16, 24, 25 for this purpose, who recommends specific alcohol-based formulations that take into account antimicrobial efficacy, local production, distribution, safety, and cost issues at a country level worldwide. 7 in some religions, alcohol use is prohibited or considered an offense requiring a penance (sikhism) or is considered to cause mental impairment (hinduism, islam) ( table 2) . nonetheless, in theory, those religions with an alcohol prohibition in everyday life demonstrate a pragmatic vision that allows acceptance of the most valuable approach in the perspective of optimal patient care delivery. despite this generally tolerant approach, however, the religious background still may influence some health care workers who are unwilling to use alcohol-based formulations due to either reluctance to come in contact with alcohol or concerns about alcohol ingestion, inhalation, or skin absorption. 8, 26 even the designation of a product simply as an ''alcohol-based formulation'' could become an obstacle for the implementation of worldwide recommendations. islamic tradition poses the toughest challenge to alcohol use. alcohol is clearly defined as forbidden (haram) in islam, and some muslim health care workers may feel ambivalent about using alcohol-based hand rub formulations. but in fact the qu'ran permits the use of any substance that man can manufacture or develop to reduce illness or contribute to better health, including alcohol used as a medicinal agent. similarly, cocaine is allowed for use as a local anesthetic, but not as a recreational drug. to better understand muslim health care workers' attitudes toward alcohol-based hand cleansers in an islamic country, the study by ahmed et al 26 conducted in the kingdom of saudi arabia is very instructive. interestingly, although saudi arabia is considered the historic epicenter of islam, no state policy or permission or fatwa (islamic religious edict) was sought for the approval of alcohol-based hand rubs. indeed, hand rub dispensers have been installed in numerous health care settings since 2005. 26 this experience demonstrates that alcohol-containing hand rub solutions are indeed finally acceptable to many muslim health care workers, even within an islamic kingdom legislated by sharia (islamic law), and this may encourage other muslims to reconsider their attitude (fig 2) . one concern of health care workers regarding the use of hand rub formulations is the potential systemic diffusion of alcohol or its metabolites after skin absorption or airborne inhalation. only a few anecdotal and unproven cases of alcohol skin absorption leading to clinical symptoms have been reported in the literature. 27, 28 in contrast, reliable studies on human volunteers clearly demonstrate that the quantity of alcohol absorbed after application is minimal and well below toxic levels for humans. [29] [30] [31] [32] in a study mimicking high-quantity, high-frequency use, 31 the cutaneous absorption of 2 alcohol-based hand rubs with different alcohol components (ethanol and isopropanol) was carefully monitored. whereas insignificant levels of ethanol were measured in the breath and serum of a minority of the participants, isopropanol was not detected. finally, alcohol smell on the skin may be an additional barrier to the use of hand rubs; further product development should be conducted to eliminate this smell from hand rub preparations. in addition to targeting areas for further research, some possible solutions to existing problems may be identified (table 3) . for example, starting in childhood, the inherent nature of hand hygiene, which is strongly influenced by religious habits and norms in some populations, could be shaped in favor of an optimal elective behavior toward hand hygiene. indeed, some studies have demonstrated that it is possible to successfully educate children of school age to practice optimal hand hygiene to help prevent common pediatric community-acquired infections. [33] [34] [35] when preparing such guidelines, international and local religious authorities should be consulted and their advice clearly reported. an example of this is the statement issued by the muslim scholars' board of the muslim world league at its 16th annual meeting in mecca, saudi arabia, in january 2002: ''it is allowed to use medicines that contain alcohol in any percentage that may be necessary for manufacturing if it cannot be substituted. alcohol may be used as an external wound cleanser, to kill germs and in external creams and ointments.'' 36 in hand hygiene promotion campaigns in health care settings in which religions prohibiting the use of alcohol are represented, educational strategies should include focus groups on this topic to allow health care workers to openly raise their concerns regarding the use of alcohol-based hand rubs, help them understand the scientific evidence underlying this recommendation, and identify possible solutions to overcome obstacles ( table 3) . results of these discussions could be summarized in an information leaflet to be produced and distributed locally. it has been suggested that in settings in which the observance of related religious norms is very strict, the term ''alcohol'' be avoided in favor of the adjective ''antiseptic'' when describing hand rubs. but concealing the true nature of the product by using a nonspecific term may be construed by some as deceptive and considered unethical. further research is needed before any final recommendation along these lines can be made. finally, the opportunity to involve patients in a multimodal strategy to promote hand hygiene in health care should be carefully evaluated. despite its potential value, this intervention may be premature in settings in which religious proscriptions are taken literally; rather, it could be a later step, after the achievement of awareness and compliance among health care workers. religious faith has made many important contributions to the ethics of health care and has helped focus the attention of health care providers on both the physical and spiritual nature of humans. however, wellknown examples exist of health interventions in which a religious viewpoint had a critical impact on implementation or even interfered with it. 37, 38 an awareness of commonly held religious and cultural beliefs is vital when attempting to apply innovative concepts of modern medicine and implementing good clinical practice in today's increasingly mobile, multicultural health care community. in response to the challenge of incorporating an understanding of religious and cultural beliefs into programs to promote hand hygiene compliance, our study has identified some of the implications of those beliefs, has offered some potential solutions in response, and has suggested some areas for future research. the global patient safety challenge guideline for hand hygiene in health care settings. recommendations of the healthcare infection control practices advisory committee and the hicpac/shea/apic/idsa hand hygiene task force. society for healthcare epidemiology of america/association for professionals in infection control/infectious diseases society of america hand hygiene and patient care: pursuing the semmelweis legacy perneger tv, and the members of the infection control program. compliance with handwashing in a teaching hospital hand hygiene among physicians: performance, beliefs, and perceptions patient safety: a global priority clean care is safer care: a worldwide priority world health organization. who guidelines on hand hygiene in health care (advanced draft) hand hygiene: simple and complex culturally sensitive care of the muslim patient religion-based tobacco control interventions: how should who proceed? religion and health: a review and critical analysis the 2005 annual megacensus of religions why healthcare workers don't wash their hands: a behavioral explanation behavioural considerations for hand hygiene practices: the basic building blocks muslim teaching gives rules for when hands must be washed maintaining cleanliness and protecting health as proclaimed by koran texts and hadiths of mohammed savs you need hands constructing shared understanding: the role of non-verbal input in learning contexts teachers' gestures facilitate students' learning: a lesson in symmetry effectiveness of a hospital-wide programme to improve compliance with hand hygiene culture, religion and patient care in a multi-ethnic society. london: age concern books culture, religion and patient care in a multi-ethnic society. london: age concern books use alcohol hand rubs between patients: they reduce the transmission of infection cost implications of successful hand hygiene promotion hand hygiene and the muslim healthcare worker topical absorption of isopropyl alcohol induced cardiac and neurologic deficits in an adult female with intact skin gait disturbance, confusion and coma in a 93-year-old blind woman dermal absorption of isopropyl alcohol from a commercial hand rub: implications for its use in hand decontamination alcohol-based hand sanitizer: can frequent use cause an elevated blood alcohol level? can alcohol-based hand-rub solutions cause you to lose your driver's license? comparative cutaneous absorption of various alcohols quantity of ethanol absorption after excessive hand disinfection using three commercially available hand rubs is minimal and below toxic levels for humans effect of hand sanitizer use on elementary school absenteeism effect of handwashing on child health: a randomized controlled trial a systematic review of the effectiveness of antimicrobial rinse-free hand sanitizers for prevention of illness-related absenteeism in elementary school children resolutions of the islamic fiqh council crusading for change key: cord-261736-jlwctmxw authors: marchand, geneviève; duchaine, caroline; lavoie, jacques; veillette, marc; cloutier, yves title: bacteria emitted in ambient air during bronchoscopy—a risk to health care workers? date: 2016-12-01 journal: am j infect control doi: 10.1016/j.ajic.2016.04.241 sha: doc_id: 261736 cord_uid: jlwctmxw background: health care workers are at risk of occupational infections, and some procedures are known to increase this risk. the aim of this study was to qualify and quantify bioaerosol concentrations during bronchoscopy to estimate the occupational risk. methods: full-day sampling was conducted in 2 rooms while bronchoscopies were performed on patients. two microbial air samplers were used, a wet wall cyclonic sampler and an impactor, on culture media. identification of the culturable bacterial flora was performed with chromatographic analysis of cellular fatty acid of the isolated strain and additional biochemical tests if needed. specific polymerase chain reaction analysis was completed on wet wall cyclonic samples for the detection of influenza a and b and mycobacterium spp. results: a wide variety of bacteria were collected from the ambient air. all samples yielded at least 1 staphylococcus species. although most of the culturable bacteria identified were normal nonpathogenic flora, such as streptococcus spp, neisseria spp, and corynebacterium spp, some opportunistic pathogens, such as streptococcus pneumoniae, were found. neither mycobacterium spp nor influenza virus was detected with the polymerase chain reaction method during this study. conclusions: culturable bacteria from oral, nasal, and pulmonary flora are aerosolized during bronchoscopy and could be inhaled by medical staff. the potential presence of pathogens in those aerosols could represent an occupational infection risk. health care workers (hcws) are at risk of occupational infections due to the nature of their work. 1 even when safety protocols are implemented, hcws are still considered to be at continued occupational risk of many infectious diseases transmitted from ill patients. 2 although transmission of highly infectious diseases from patients to hcws is uncommon, a number of cases have been reported. 3 several cases of transmission of streptococcus pyogenes to hcws have been described. [3] [4] [5] [6] neisseria meningitis, haemophilus influenza, and acinetobacter baumanii are other well-documented occupational pathogen infections acquired by hospital personnel. 3, [7] [8] [9] the risk of influenza pandemics, emerging infections, and antimicrobial resistance of bacteria has raised concerns about the health of hcws 10 and therefore about prevention practices that should be followed during particular procedures. worldwide, hcws are reported to account for 20% of all cases of acquired severe acute respiratory syndrome. 11 some medical procedures increase the risk of occupational infections because of exposure to airborne pathogenic microorganisms. staff can be infected during routine endoscopy procedures. 12 accordingly, endoscopists show a higher seropositivity to helicobacter pylori. 13, 14 transmission of tuberculosis from infected patients undergoing bronchoscopy is another recognized occupational risk. 15 , 16 catanzaro 15 calculated that during intubation and bronchoscopy, more than 200 units per hour of infectious mycobacteria are aerosolized from a patient. intubation with a bronchoscope stimulates a patient's coughing reflex. 17, 18 coughing produces droplets of various sizes, 18 many of which are inhalable and can be drawn deep down into the lungs. [19] [20] [21] particles of saliva, mucus, and pathogenic microbes can be emitted when a patient coughs. because particles of this kind originate from a deeper area of the respiratory system, the droplets released by coughing may be more infectious than those from sneezing. [22] [23] [24] [25] many of these particles are small enough to remain suspended in the air for a long time, and through evaporation, larger particles can become small enough to remain suspended in the air for an extended period also. 26 from the perspective of infectious disease spread by the airborne route, inhalable particles include particles in the size range from 0.1-10 μm in diameter. if particles carrying pathogens are inhaled, they may be deposited in parts of the respiratory tract where they are likely to cause infection and disease. 20, 26 although some researchers have reported on the infectious risk to hcws performing high-risk procedures, to our knowledge, no study has ever documented, during bronchoscopy procedure, the real bioaerosol exposure of hcws. davies et al 27 reported in their 2009 review that "no quantitative study has yet been carried out on aerosol generating procedures," and that "uncertainty surrounding aerosol generating procedures make it difficult to construct effective infection control policy." the aim of this study was to qualify and quantify bioaerosol concentrations during bronchoscopy to evaluate the occupational risk to hcws. knowing the real exposure is essential to encouraging hcws to implement better prevention protocols and wear personal protective equipment if needed. this study has been approved by the ethics boards of the 2 involved hospitals and by the university of quebec in montreal ethics board. two bronchoscopy rooms in 2 different hospitals were investigated. the first room had a volume of 79 m 3 and was located in a recently constructed building. it had negative pressure in relation to its anteroom, with 12 air changes per hour. room b was smaller, with a volume of 59.8 m 3 . three air outlets equipped with highefficiency particulate air filters expelled the air directly outdoors. the room is located in an older hospital built in the 1930s. extensive renovations have been done over the years, and the current configuration dates from 2010. bacteria collected were analyzed by culture, whereas mycobacterium spp and influenza a and b viruses were analyzed by molecular biology methods. one full day of sampling was carried out in each bronchoscopy room. depending on the bronchoscopy procedure time, up to 8 samples were collected per patient. in room a, 5 bronchoscopies were performed during the sampling day, for a total of 24 culturable samples. in room b, 10 bronchoscopies were performed, for a total of 37 culturable samples. the measurements were taken consecutively for all steps in the bronchoscopy procedure, from the arrival of the patient through his or her departure. at the beginning of the day, before the first bronchoscopy, samples were taken to establish the background concentrations in the room. at both hospitals, 1 member of the research team was permitted by the medical staff to remain in the bronchoscopy room. all samples were collected at a fixed station located within a radius of 1.5 m from the patient's mouth and the workers' breathing zone. sampling continued for 20 minutes at the end of the day to determine whether bioaerosol concentrations would return to their morning background levels during this time. twenty minutes was chosen because that is the recommended waiting time before re-entering a room after a procedure has been performed on a patient with tuberculosis. on average, 4 people (research team member, doctor, nurse, and patient) were present in the room. the sampling devices used to assess the bioaerosols were the andersen n6 impactor (andersen instruments, atlanta, ga) for the culturable bacteria and the coriolis μ biological air sampler (bertin technologies, montigny-le-bretonneux, france) for the molecular biology analysis. the andersen impactor is known as a standard for culturable bioaerosol analysis. 28 five-minute sampling periods were used. the pump flow rate was adjusted in the bronchoscopy room to 28.3 lpm using a tsi mass flowmeter 4199 (tsi inc, shoreview, mn) and checked between patients. the total volume of air sampled was used to calculate the culturable bacterial concentrations. the andersen samplers were loaded with 90-mm petri dishes containing trypticase soy agar media to which 5% defibrinated sheep blood was added (oxoid, ontario, canada). all dishes were incubated at 37°c for 48 hours. all colonies were enumerated according to the total count method. 29 the limit of detection was 7 cfu/m 3 air for the andersen impactor. the cyclonic coriolis μ sampler was used at a flow rate of 150 lpm. fifteen milliliters of sterile 1× phosphatebuffered saline solution, ph 7.4 (life technology, ontario, canada), were placed in the conical vials. a sampling time of 10 minutes was used to obtain an adequate detection limit of 1,200 genomes. as with the andersen impactor, > 1 sample was taken for some patients. identification was performed with the sherlock microbial identification system (midi, newark, de) using fatty acid extraction analysis by instant fame (fatty acid methyl ester) on pure culture of each isolated strain. 30 the clinical aerobes (iba) method following the manufacturer's protocol was used. each strain was grown on trypticase soy agar blood and incubated at 35°c for 24 ± 2 hours. some slow grower strains needed an extra 24 hours. two to 3 mg bacteria cells were harvested for the fatty acid extraction. identification to the species level was completed if the similarity index was > 0.6; the gram stain and the phenotypic characteristics needed to match. when identification was not possible with the sherlock microbial identification system, the gen-iii microplate (biolog, hayward, ca) or the microscan neg id type 2 panel or pos id type 3 panel (beckman coulter, mississauga, ontario, canada) was used to complete the identification. 31 even with the 3 systems, some strains could not be identified to the species level. aliquots of coriolis μ air samples (1.5 ml) were centrifuged (10 minutes at 14,000 × g) and the pellets were stored at -20°c until extraction. total genomic dna was extracted using the powerlyzer ultraclean microbial dna isolation kit (mo bio laboratories, carlsbad, ca) according to the manufacturer's instructions. the dna extraction homogenization was performed with a mixer mill mm301 (retsch, düsseldorf, germany) at 20 movements per minute for 10 minutes. total dna was eluted in 50 μl elution buffer. the rna was extracted with the magmax viral rna isolation kit (thermo fisher scientific, waltham, ma). amplifications were performed using the bio-rad cfx384 thermocycler (bio-rad laboratories, mississauga, ontario, canada). previously published primers and probes were purchased from integrated dna technologies (coralville, ia). the detection systems used were specific for influenza a and b viruses and for bacteria of the genus mycobacterium. [32] [33] [34] the polymerase chain reaction mixture contained 2 μl dna/rna template, 0.4 μmol/l (each) primer, 0.08 μmol/l probe, and 10 μl 2 × quantitect probe pcr master mix (qiagen, mississauga, ontario, canada) in a 20-μl reaction mixture. the results were analyzed using bio-rad cfx manager software, release 3.0.1224.1015 (bio-rad laboratories). an analysis of variance statistical test followed by a tukey-kramer multiple-comparison test was performed on log-transformed concentrations measured in the 2 rooms to determine whether a difference could be observed between the periods. four periods were compared: the background measured in the morning, the waiting and preparation of the patient, the bronchoscopy procedure, and the return to background at the end of the day. the average concentrations (colony forming units/meters 3 of air) and the standard deviations of the culturable bacteria measured in the 2 bronchoscopy rooms are presented in table 1 . the bacterial identifications obtained are shown in table 2 . because of the high bacterial diversity found, pure culture isolation was done on the most frequently observed colony phenotypes to perform the strain identifications. all the staphylococcus spp strains were confirmed not to be staphylococcus aureus. the average concentrations measured in room a varied from 43-100 cfu/m 3 air. in room b, the average concentrations were higher, ranging from 40-370 cfu/m 3 . the highest concentration (580 cfu/m 3 air) was measured during the second bronchoscopy procedure of the day in room b. neither mycobacterium spp nor influenza a and b viruses were detected in our investigations. the results of the tukey-kramer test done on the logtransformed concentrations are presented in figure 1 . the test confirmed that the concentrations, measured during the bronchoscopies and the preparation of the patient, were significantly higher than the ones measured during the return to background at the end of the day. the morning background concentrations, on the other hand, were not significantly different, although they appeared to be lower than those found during the medical procedures. to our knowledge, this is the first study to measure and identify the actual bacterial flora present in the ambient air of a room while bronchoscopies are being performed on patients. although bronchoscopy has been identified as a high-risk procedure for hcws, 10, 15, 35, 36 this recognition had until now been based on risk guesstimate and epidemiologic studies, but actual exposure had never been documented as it is here. sampling of the ambient air of the 2 bronchoscopy rooms yielded a wide diversity of bacteria. many sources of bioaerosols were identified, including outdoor air, medical staff, patients, and resuspension from surfaces. during the background and medical procedure periods, the concentrations and diversity of bacteria in the 2 rooms were noticeably different. according to brandl and mandal, 37 the main factors affecting the levels and diversity of airborne microorganisms in the indoor air of hospitals are the lack of cleanliness of the hospital, human activities, organic materials brought in from outdoors, and the efficiency of the hospital ventilation system. in general, the predominant genera of airborne bacteria reported in hospitals by other researchers are staphylococcus, bacillus, micrococcus, and corynebacterium. [37] [38] [39] this was confirmed by our study, because at least 1 species of staphylococcus spp was identified in every sample. microorganisms from environmental and human sources were anticipated, and their presence was confirmed by our investigations. some of the bacteria identified are known to originate from the human buccal cavity and respiratory tract. patients undergoing bronchoscopy cough numerous times, especially when the bronchoscope is being inserted. because it is well known that coughing produces a high number of aerosol particles, 17, [19] [20] [21] 40 it would seem logical to attribute a proportion of the microorganisms found in the ambient air to the patient's respiratory system. short-term variation in, or sporadic appearance of, specific bacteria cannot be attributed to the background 4 58 64 2 50 14 1 2 60 0 4 208 105 2 2 100 42 3 370 193 3 1 60 4 105 37 4 8 76 24 3 136 46 5 3 53 25 3 183 64 6 2 50 28 7 2 165 106 8 1 310 9 16 0 hcws because they are present during all bronchoscopies. certain bacteria most definitely originate from the patients, such as the streptococcus pneumoniae found in room b during the second bronchoscopy. the fact that culturable bacteria from patients were found in the air 1.5 m from their mouths indicates that hcws in closer proximity can be exposed to some pathogenic microorganisms. the survival capacity of microorganisms is often overlooked, but it can greatly affect the bioaerosol content of the air in a room. nosocomial pathogens can persist on inanimate surfaces. 41 like dust, microorganisms deposited on the floor or other surfaces can be resuspended in the air as a result of people moving around, rolling stretchers in and out of the room, or any other air disturbance that might occur. 42, 43 pathogens present in the air can therefore originate from previous patients, which underscores the importance of thorough room cleaning. the higher concentrations measured during the waiting/preparation period may well be explained by bacteria from the floor being resuspended in the air by the rolling of stretchers and by nurses walking around the room during that period. in this study, whereas most of the culturable bacteria identified (brevundimonas diminuta, corynebacterium pseudodiphthericum, gordonia terrae, moraxella sp, psychrobacter phenylpyruviens, and actinomycetes) are nonpathogenic to humans in good health, some opportunistic pathogens (streptococcus pneumoniae, acinetobacter radioresistens, acinetobacter lwoffi, and escherichia sp) were found. mycobacterium spp and influenza a and b viruses were not detected. pathogens present in the air are undoubtedly dependent on patient pathology, and the absence of any specific pathogens from the samples collected in this study does not mean they will always be absent. the identification of streptococcus pneumoniae, neisseria sp, and corynebacterium sp shows that culturable bacteria from oral, nasal, and pulmonary flora were present in the air of the rooms during bronchoscopy procedures. hcw exposure to bioaerosols needs to be managed by implementation of prevention protocols and by providing them with appropriate personal respiratory protection if necessary. as previously pointed out, the main problem is not the treatment of known tuberculosis patients, but that of patients admitted for other problems with unsuspected or undiagnosed tuberculosis. 15, 44 because hcws never know what is hiding in the lungs of their patients, emphasis must be placed on prevention and protection. bioaerosol concentrations in the working zone of hcws are certainly higher than those reported here. in fact, given the distance between the sampling zone and the hcws, the concentrations measured may well have been reduced as a result of dilution or sedimentation of the particles. the implication is that a sampling zone located closer to a patient's mouth would have revealed higher concentrations and perhaps the presence of other strains of microorganisms. sample size was also a limitation of the study. our presence in the room needed to be accepted by the medical staff. only 1 sampling day was allowed in each hospital, and the number of bronchoscopy procedures was limited on those days. still, in this study, the number of bronchoscopies necessary to be statistically representative (p ≤ .05) with an acceptable error of 20% was calculated to be 14. 45 nevertheless, this study still raises concerns about the occupational hazards to which hcws are exposed. it provides clear evidence of the presence of culturable opportunistic bacteria originating from the respiratory tract of patients in the air of bronchoscopy rooms. the presence of pathogenic microorganisms in the air of these rooms is to be expected from time to time, depending on patient pathology. quantifying the risk of respiratory infection in healthcare workers performing high-risk procedures lessons learned: protection of healthcare workers from infectious disease risks 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bronchoscopy. ottawa (on): public health agency of canada helicobacter pylori prevalence in endoscopy and medical staff occupationally acquired infections in health care workers: part ii nosocomial tuberculosis 1, 2 occupationally acquired infections in health care workers: part i cough frequency and infectivity in patients with pulmonary tuberculosis 1 occupational tuberculous infections among pulmonary physicians in training coughgenerated aerosols of mycobacterium tuberculosis: a new method to study infectiousness quantity and size distribution of cough-generated aerosol particles produced by influenza patients during and after illness cough-generated aerosols of pseudomonas aeruginosa and other gram-negative bacteria from patients with cystic fibrosis airborne transmission of disease in hospitals understanding the symptoms of the common cold and influenza global physiology and pathophysiology of cough: accp evidencebased clinical practice guidelines protecting the faces of health care workers: knowledge gaps and research priorities for effective protection against occupationally-acquired respiratory infectious diseases toward understanding the risk of secondary airborne infection: emission of respirable pathogens a review of the risks and disease transmission associated with aerosol generating medical procedures evaluation of eight bioaerosol samplers challenged with aerosolof free bacteria new sampler for the collection, sizing, and enumeration of viable airborne particles identification of bacteria by gas chromatography of cellular fatty acids preliminary evaluation of biolog, a carbon source utilization method for bacterial identification multiplex pcr assay for immediate identification of the infecting species in patients with mycobacterial disease evaluation of three influenza a and b real-time reverse transcription-pcr assays and a new 2009 h1n1 assay for detection of influenza viruses world health organization. cdc protocol of real-time rtpcr for swine influenza a (h1n1) aerosol generating procedures and risk of transmission of acute respiratory infections to healthcare workers: a systematic review environmental and occupational medicine bioaerosols in indoor environment-a review with special reference to residential and occupational locations distribution characteristics of airborne bacteria and fungi in the general hospitals of korea airborne bacteria and antibiotic resistance genes in hospital rooms dispersion and exposure to a cough-generated aerosol in a simulated medical examination room how long do nosocomial pathogens persist on inanimate surfaces? a systematic review elevated personal exposure to particulate matter from human activities in a residence human occupancy as a source of indoor airborne bacteria the hazard is relative sampling strategies for airborne contaminants in the workplace. leeds: h and h scientific consultants the authors thank yves beaudet, carole pépin, and nancy lacombe for their technical assistance. key: cord-297462-c5hafan8 authors: tang, lu; bie, bijie; zhi, degui title: tweeting about measles during stages of an outbreak: a semantic network approach to the framing of an emerging infectious disease date: 2018-06-19 journal: am j infect control doi: 10.1016/j.ajic.2018.05.019 sha: doc_id: 297462 cord_uid: c5hafan8 background: the public increasingly uses social media not only to look for information about emerging infectious diseases (eids), but also to share opinions, emotions, and coping strategies. identifying the frames used in social media discussion about eids will allow public health agencies to assess public opinions and sentiments. method: this study examined how the public discussed measles during the measles outbreak in the united states during early 2015 that originated in disneyland park in anaheim, ca, through a semantic network analysis of the content of around 1 million tweets using kh coder. results: four frames were identified based on word frequencies and co-occurrence: news update, public health, vaccination, and political. the prominence of each individual frame changed over the corse of the pre-crisis, initial, maintenance, and resolution stages of the outbreak. conclusions: this study proposed and tested a method for assessing the frames used in social media discussions about eids based on the creation, interpretation, and quantification of semantic networks. public health agencies could use social media outlets, such as twitter, to assess how the public makes sense of an eid outbreak and to create adaptive messages in communicating with the public during different stages of the crisis. emerging infectious diseases (eids) present novel and unfamiliar risks to the public. as a new tool for strategic communication during eid outbreaks, social media allows government agencies such as the centers for disease control and prevention (cdc) to reach wider audiences. 1 as a platform based on user-generated content, social media enables the public to share opinions and sentiments during these outbreaks. one such eid is measles. measles is a highly contagious and acute illness that can lead to pneumonia, encephalitis, and death. 2 it was declared eliminated in the united states in 2000 as the result of the successful nationwide administration of a 2-dose vaccination (ie, measles, mumps, and rubella vaccine). however, recent years have witnessed the re-emergence of measles outbreaks. 2 most of these outbreaks were associated with imported cases; at the same time, a decrease in the domestic vaccination rate has made the country increasingly vulnerable during such outbreaks. presented here is a semantic network analysis of twitter content about measles during the measles outbreak that first appeared in california during early 2015. examining the most frequently used key words and their co-occurrences allows researchers to induce a semantic network that represents the major frames used in large amounts of text. frames represent the cognitive structure people use in understanding and communicating issues. through framing, media and individuals choose to highlight certain aspect of the crisis while downplaying other aspects. 3 this study adds to the research on crisis and emergency risk communication by demonstrating that social media users applied different frames to understand the public health crisis associated with a measles outbreak: news update frame, public health frame, vaccination frame, and political frame. in terms of research methodology, this study demonstrates the feasibility of identifying frames through semantic network analysis. practically, the findings of the study allow public health professionals to understand how social media users make sense of an eid during different stages of the outbreak so that they can develop more effective crisis communication strategies. social media plays an essential role in the dissemination of information on eids. what social media users post, share, like, and comment on reflects not only what information is available, but also what they consider important. researchers have used social media data to assess public perceptions, sentiments, and responses toward eid outbreaks such as the 2009 h1n1 outbreak, 4 the 2011 european escherichia coli outbreak, 5 the 2014 ebola virus disease outbreak, 6 and the 2013-2014 measles outbreak in the netherlands. 7 with the exception of lazard et al, 6 all these studies examined social media contents deductively based on pre-existing categories through either manual coding or text mining based on manually coded training dataset. semantic network of social media contents represents a new lens through which researchers could inductively investigate how the public thinks and feels during an eid outbreak without the need for a training dataset. semantic networks represent the semantic relationships among a set of words. 8 semantic network analysis is both a theoretical framework and a quantitative text analysis method that uncovers the structure of relationships among words. 9 in a semantic network, word-use frequencies and co-occurrence of the most frequently occurring words represent shared meanings and common perceptions in people's minds. 9 semantic networks can be used to infer the frames used in texts. framing is the process by which organizations and individuals choose to report or discuss an event (such as a public health crisis) by selectively highlighting certain aspects and downplaying other aspects of the event. 3 researchers have explored the frames used by different stakeholders facing a crisis through the examination of semantic networks. david et al 10 examined 6 pre-established frames about population issues in news articles in the philippines by looking at weighted semantic networks between 1986 and 2000. however, a strength of semantic network analysis is it allows new and unfamiliar frames to emerge from the data inductively. for instance, schultz et al 11 studied the associative frames used by public relations professionals and news media in the united states and united kingdom after the 2010 bp oil spill into the gulf of mexico and found that bp framed the oil spill as caused by external factors and downplayed internal factors (such as company's behaviors), whereas the news media adopted more complicated frames. van der meer et al 12 compared the frames used by public relations professionals, news media, and the public in times of crises such as explosions and volcano eruptions by examining the semantic networks and found the frames used by these groups converged overtime. tian and stewart 13 compared the semantic networks based on word cooccurrence in cnn and bbc online news report about severe acute respiratory syndrome and found that although both news outlets used the public health frame, cnn used the economic impact frame, and bbc used the outbreak impact frame. exploring frames during a measles outbreak as indicated by semantic networks by twitter users can provide insights into how social media users make sense of the crisis and what issues concern them. hence, the first research question (rq) was proposed. rq1: what are the frames used in the twitter discussion about the 2015 measles outbreak as indicated by semantic networks? crisis communication takes different forms in different stages of the crisis. reynolds and seeger 14 identified a stage-based model of crisis and emergency risk communication, which includes 5 stages: pre-crisis, initial event, maintenance, resolution, and evaluation. each of these stages is associated with different tasks for crisis communication. although this model was proposed as a strategic tool for guiding the crisis communication of government agencies such as the cdc, it nevertheless shows that the public goes through different stages in information processing and sensemaking about public health crises such as a measles outbreak. as a result, they are likely to use different frames to discuss measles on twitter during each stage of the crisis. hence, we asked the next rq: rq2: how does the use of different frames change over different stages of the outbreak? because the most recent measles outbreak in the united states occurred between december 2014 and april 2015, 2 tweets including the word measles posted between december 1, 2014, and april 30, 2015, were purchased from discovertext.com (n = 1,154,156). using this time frame allowed us to look at the twitter discussion before, during, and after the outbreak. first, raw texts were cleaned and transformed into an appropriate format to be mined. 10 non-english tweets were excluded, resulting in 1,133,656 tweets. for the purpose of semantic network analysis, urls in tweet texts were deleted. special characters such as \,^, and $ as well as user names mentioned after @ were also deleted from tweet texts. next, stop words were excluded, including conjunctions, auxiliary verbs, and transitive verbs, among others. 12 plural forms of words were replaced by singular forms and high frequency words sharing the same root were combined into single words to facilitate the analysis. 10 similarly, multiword phrases with the same meaning were combined. semantic network analysis was conducted to answer the rqs proposed. first, the content of tweets was analyzed to calculate the frequency of words and determine the most frequently co-occurring word pairs using kh coder version 2.00f, a free software for analyzing text and identifying co-occurrence networks (available for download at https://sourceforge.net/projects/khc/). when the data were loaded into the program, a word frequency table and a word co-occurrence network were generated. each individual tweet was a unit of analysis and word pair co-occurrence was defined as the appearance of 2 words in the same tweet. to explore the dynamic nature of twitter discussion during an eid outbreak, the duration of the measles outbreak was divided into 4 stages. the pre-crisis stage (stage 1) was between december 1, 2014, and january 4, 2015. the first cases of this outbreak were reported on january 5, which marked the beginning of outbreak and thus the initial stage (stage 2). 2 the maintenance stage (stage 3) started on january 28, when the number of new cases started to decline and ended on march 6, when the last case in this break was reported. the resolution stage (stage 4) was between march 7 and april 17, when the cdc announced this outbreak to be officially over. 2 five days were selected for each stage. to be included in the final semantic network, a word or multiword phrase must have appeared in more than 1% of tweets and be involved in the top-60 edges (connections) of each stage filtered based on jaccard coefficient. 15 jaccard coefficient 16 is a statistical measure widely used for assessing similarity between objects (jaccard, 1912) . the values of jaccard coefficient vary between 0 and 1. in kh coder, words that appear frequently in the same tweet are considered to be closely associated, and their jaccard coefficient become closer to 1. to facilitate a more nuanced understanding of the network structure during different stages of outbreak progression, an inductive approach was adopted to identify potential frames based on the high-frequency words and co-occurrence links among them. 17 the visualization of the semantic networks was accomplished using graphviz (http://graphviz.org). to explore the longitudinal changes in the use of the 4 frames identified, dictionaries containing key words associated with each frame were created based on the semantic networks identified and on the authors' further reading of tweets adopting these frames. tweets were labeled as containing a frame based on the presence of tags (ie, frame-relevant terms). in other words, each tweet was labeled by a unique set of key words. for example, the groups of words classified as news update frame included california, disney, utah, january, visitor, official, and today. the list of words associated with the public health frame included cdc, patient, disease, contract, infectious, and virus, among others. the vaccine frame, which included any mention of vaccine-related issues, was associated with key terms such as vaccine, antivaccine, unvaccinate, unvaccinated, inhaled measles vaccine, safety, immunity, and jenny mccarthy (an actress often associated with the anti-vaccine movement). finally, the political frame was associated with terms such as obama, republicans, democrats, immigration, illegal, lawmaker, debate, governor christie, and politics. a single tweet can be labeled as using 1 frame, multiple frames, or none of the frames. next, percentages of tweets using different frames were calculated for the 4 stages identified and χ 2 tests were run to see whether the differences among stages were statistically significant. bonferroni correction was conducted to account for the effects of multiple testing. overall, original tweets (n = 567,391) accounted for 50.05% of all tweets collected (n = 1,133,656). as shown in figure 1 , although the numbers of tweets and retweets were similar during the most active part of the outbreak, retweets outnumbered original tweets mostly in early february during the maintenance stage. figure 2 represents the semantic network of twitter content about measles during the entire outbreak. four distinct frames were identified inductively based on the reading of the semantic networks and tweets containing the key words included in these semantic networks: news update frame, public health frame, vaccine frame, and political frame. the titles of these frames were coined by the authors based on the typical message carried in each frame, similar to the practice described in odlum and toon (2015) . 18 the news update frame provided news and updates about suspected and confirmed cases of measles before, during, and after the outbreak. typically, a tweet adopting the news update frame included the number of cases in a geographic location; for example, "california reports 4 more measles cases." tweets using the news update frame did not typically contain opinions. tweets adopting the public health frame conveyed medical information such as symptoms of measles, methods of prevention, and treatment. for instance, the following tweet introduced a new complication of measles: "eye complications possible with measles warn ophthalmologists." tweets using the public health frame educated the public about measles and sometimes included behavior recommendations. the vaccine frame referred to the discussion and debates about the safety and necessity of vaccination. tweets using this frame were often emotionally charged. an example of a provaccine tweet was: "if i get measles because some nitwit talked my parents into not vaccinating me, somebody's getting their ass kicked." an example of an anti-vaccine tweet was: "measles vaccine kills 6 kidsmedia blackout." the political frame was used in those tweets that presented the causes of and solutions for the measles outbreak in political terms. some twitter users blamed the outbreak on the influx of illegal immigrants and called for tighter immigration law and border control. the political frame was also used in tweets debating governmental policies on vaccination and disease prevention. an example of a tweet using the political frame was: "am i the only one wondering if the surge of illegals in 2014 has anything to do with the measles outbreaks we see now?" across the 4 stages of the outbreak, the pre-crisis stage had the fewest original tweets (n = 2,182), whereas the maintenance stage included 137,233 original tweets, followed by the initial stage (n = 13,556) and the resolution stage (n = 8,702). the use of the 4 frames showed different patterns in the 4 stages of the outbreak (see fig 3) . the news update frame appeared to be the most dominant frame during the initial and resolution stages. the public health frame was 1 of the 2 most dominant frames in the precrisis stage; however, its use decreased during the initial stage and was lowest during the maintenance stage. the use of the vaccine frame increased from pre-crisis stage to the initial stage and the vaccine frame became the most dominant frame during the maintenance. the political frame was the least often used frame in all 4 stages of the outbreak and appeared most frequently during the maintenance stage. a series of χ 2 tests showed that the use of these frames was significantly different across the 4 stages of the outbreak (see table 1 ). pairwise χ 2 tests were conducted to further explore the differences among these 4 stages in the use of frames (see table 2 ). specifically, the following 3 pairs of comparisons were performed based on the chronological order of development stages: the precrisis stage versus the initial stage, the initial stage versus the maintenance stage, and the maintenance stage versus the resolution stage. all of the pairwise comparisons were significant at the adjusted p < .001 level, except for the use of the political frame in pre-crisis and initial stages. social media allows the assessment of public opinions, sentiments, and responses during an eid outbreak. our study examines the frames used in twitter discussion during the 2015 measles outbreak through a semantic network analysis. this study finds that around half of tweets are retweets. furthermore, retweets outnumbered original tweets during the early days of the maintenance stage. this stands in contrast with the findings of previous studies. for instance, liu, kliman-silver, and mislove 19 found that overall around 30% of tweets are retweets. radzikowski et al 20 studied the tweets about vaccines during the later stages of the 2015 measles outbreak (the maintenance stage in our study) and found around 44% of tweets in their data corpus were retweets. our data also suggest the highest rate of retweets during this stage, although our data were about measles instead of vaccine. it is possible that the maintenance stage sees more reflection and activism when the immediate threat of the outbreak has been contained and thus is associated with more retweets. the current study identified 4 major frames that emerged organically from the semantic network based on word frequencies and co-occurrence. each frame highlighted an important dimension of measles-related discussion on twitter. furthermore, different stages of the outbreak witnessed fluctuations in each frame's popularity. during the pre-crisis stage, the news update frame and public health frame were the 2 most dominant frames used, whereas the vaccine frame was rarely used and the political frame was almost never used. during the initial stage, use of the news update and vaccine frames increased, although the use of the public health frame actually went down. during the maintenance stage, the vaccine frame became the most frequently used frame, followed by the news update frame, public health frame, and political frame. as the outbreak drew to an end, the use of frames revert to the pattern observed in the precrisis stage, with news update being the most used frame, followed by the public health frame, vaccine frame, and political frame. there are 2 possible explanations for the changes in how measles is framed on twitter. it is possible that the frames on twitter are influenced by the frames set by the mainstream media. for instance, lee and basnyat 21 studied media framing of the 2009 h1n1 outbreak in singapore and suggested that although traditional media predominantly used the update frame and prevention frame throughout the break, their use of frames diversified to some extent in the later stages of the crisis to include more personal frames and social frames. our semantic network shows that traditional news media (eg, cnn, cbs, reuters, and ap) featured prominently in the discussion about the measles outbreak. future research could examine the intermedia agenda setting process between traditional news media and social media in covering and framing public health crises associated with eids to see if twitter frames are influenced by the frames used in the traditional news media or if the public may influence the frames used by traditional news media through voicing their concerns and opinions in twitter. the other possible explanation for the changes in the use of frames is psychological. according to the psychometric paradigm, people's response to a risk is decided by the dread, catastrophic potential, controllability, and familiarity of said risk. 22 it is possible that during the early stages of a measles outbreak, the public is unsure about the seriousness of the risk and the controllability of the outbreak and therefore prefers the update frame and the public health frame. these 2 frames provide information that can help the public assess the scale and severity of the crisis. however, as the outbreak develops, people perceive the risks associated with measles as more familiar and more controllable. as a result, they start to try to make sense of the crisis by deciding whom they should blame for the outbreak, thereby leading to the increased use of the vaccine frame, which blames parents who refuse to vaccinate their children, as well as the political frame, which blames illegal immigrants or the government for the outbreak. through surveys, future research could establish the relationship between social media users' risk perception and the frames they apply in discussing eids. the high frequencies of the political frame during the maintenance stage, some of which state that illegal immigrants were responsible for the measles outbreak, also indicates the spread of fake news on twitter. recently, vosoughi, roy, and aral 23 found that false news stories spread further, faster, deeper and more broadly on twitter than truthful stories. compared with truth, false news stories only took one-sixth of the time to reach 1,500 people and were 70% more likely to be retweeted. these findings have particularly important implications for health care professionals during infectious disease emergencies. when rumor or misinformation gains high virality, informing and educating the public would become very challenging and difficult. radzikowski et al. studied the measles vaccination narrative in twitter by examining the semantic networks of popular hashtags and retweeting patterns in the aftermath of the outbreak. they found that although official public health agencies such as the cdc and world health organization have all entered the social media arena, mainstream media coverage about key health issues still have the power to lead online public participation. our study confirmed some of the findings of radzikowski et al. 20 that mainstream news coverage of health topics actually played a very important role in leading online audience attention and shaping public debate on social media and political frame was the most observed (9.3%) during the maintenance stage when the vaccine frame also came to its peak (39.5%). our study also extended radzikowski et al. 20 by extending the observation time, looking at twitter discussion of this outbreak as a whole from a risk communication perspective, and comparing the content patterns in different stages of the outbreak. this study proposes and tests a method for assessing the frames used in social media discussions about eids based on the creation, interpretation, and quantification of semantic networks. this method can be used to study the public response to different eid outbreaks as well as other ongoing public health crises, such as heart disease and obesity. instead of looking for known frames used in social media, this method allows the identification of unique frames associated with different public health crises. in terms of this study's practical implications, our study shows that agencies could use social media content on platforms such as twitter to assess how the public makes sense of an eid outbreak and to create adaptive messages in communicating with the public during different stages of the crisis. for instance, if it is detected that the public tends to use the vaccine frame during a certain stage of the crisis, public health agencies could design and disseminate specific social media messages to spread useful information and combat misconceptions. this study only represented an early-stage effort at mining the contents about eids on social media. future studies can take a number of directions. it is possible that individuals, government agencies, nonprofit organizations, and news media might use different frames in tweeting about measles before, during, and after an eid outbreak. further research should compare these different stakeholders' tweets. in addition, it would be of interest to study the retweeting network about eids (as done in radzikowski et al, 2016) . studying the structure of retweeting networks can shed lights on how information and opinion is diffused among twitter users. it would be useful to compare the retweeting networks during different stages of the outbreak to see if information flows differently during these stages and explore the roles played different stakeholders (eg, traditional news media, nonprofit organizations, and corporations) during across the stages. emerging infectious disease (eid) communication during the 2009 h1n1 influenza outbreak: literature review (2009-2013) of the methodology used for eid communication analysis measles -united states framing as a theory of media effects pandemics in the age of twitter: content analysis of tweets during the 2009 h1n1 outbreak tweeting during food crises: a psychosocial analysis of threat coping expressions in spain during the 2011 european ehec outbreak detecting themes of public concern: a text mining analysis of the centers for disease control and prevention's ebola live twitter chat disease detection or public opinion reflection? content analysis of tweets, other social media, and online newspapers during the measles outbreak in the netherlands in 2013 theories of communication networks what constitutes semantic network analysis? a comparison of research and methodologies news frames of the population issue in the philippines strategic framing in the bp crisis: a semantic network analysis of associative frames when frames align: the interplay between pr, news media, and the public in times of crisis framing the sars crisis: a computer-assisted text analysis of cnn and bbc online news reports of sars crisis and emergency risk communication as an integrative model network analysis of message content the distribution of the flora in the alpine zone lexical shifts, substantive changes, and continuity in state of the union discourse what can we learn about the ebola outbreak from tweets? the tweets they are a-changin': evolution of twitter users and behavior. aaai the measles vaccination narrative in twitter: a quantitative analysis from press release to news: mapping the framing of the 2009 h1n1 a influenza pandemic the perception of risk the spread of true and false news online key: cord-253240-rtv136j7 authors: mcgrath, eric j.; thomas, ronald; asmar, basim; fairfax, marilyn r.; lephart, paul; ameli, jamal; abdel-haq, nahed; salimnia, hossein title: detection of respiratory coinfections in pediatric patients using a small volume polymerase chain reaction array respiratory panel: more evidence for combined droplet and contact isolation date: 2013-03-16 journal: am j infect control doi: 10.1016/j.ajic.2013.01.010 sha: doc_id: 253240 cord_uid: rtv136j7 background: in fall 2009, children’s hospital of michigan (chm) instituted combined isolation precautions (contact and droplet isolation) for pediatric inpatients with upper respiratory infection (uri) symptoms to prevent health care-associated infection. methods: pediatric patients with symptoms of uri had nasopharyngeal (np) swab samples obtained prospectively between january and april and september and december 2010 for small volume polymerase chain reaction (svpcr) array respiratory panel (rp) multiplex nucleic acid testing. np swabs or nasal washes were obtained for viral culture and rapid antigen testing (rat). results: of 499 evaluable svpcr array rp samples, 344 (69%) tested positive for at least 1 of the 21 tested organisms. the most commonly identified pathogen was rhinovirus/enterovirus (181/344 [53%]) for which no rat exists at chm. of 344 positive specimens, 57 (17%) had at least 2 identified pathogens; 8 (2%) of these had 3. in 11% of patients, molecular testing detected pathogens or pathogen combinations requiring both contact and droplet precautions. conclusion: svpcr array rp testing detected respiratory pathogens in pediatric patients with uri at rates higher than that of rat and viral culture. because of the pathogens and pathogen combinations detected, the study findings suggest that combined contact and droplet isolation precautions may be warranted to prevent health care-associated infection in pediatric inpatients with uri. further studies will be needed to confirm these results. in fall 2009, in light of the 2009 h1n1 influenza pandemic, children's hospital of michigan (chm) instituted a policy requiring combined contact (gown and glove) and droplet (mask) isolation precautions for all inpatients with uri symptoms. determination of appropriate isolation precautions for hospitalized pediatric patients with potential respiratory coinfection is an important intervention to prevent health care-associated infections (hai). 10 cohorting of patients with clinical bronchiolitis symptoms has also been recommended in centers without private patient rooms for all admissions. however, because clinical bronchiolitis may be caused by more than 1 etiologic agent, 10 the use of rapid respiratory testing platforms gives clinicians information that may allow for more focused isolation and cohorting of patients in real time. the study hypothesis is that the use of combined isolation precautions should be continued, even after the h1n1 pandemic, in pediatric patients with uri symptoms based on the detection of pathogen coinfections by use of a small volume polymerase chain reaction (svpcr) array respiratory panel (rp) that requires both droplet and contact isolation precautions. this svpcr array rp is the first us food and drug administration (fda)-approved molecular method capable of detecting 17 viral and 3 bacterial respiratory pathogens and has been compared with other molecular testing methods. 11, 12 detroit medical center was 1 of 3 us sites involved in clinical evaluation of filmarray respiratory panel (biofire diagnostics, inc; previously idaho technology inc, salt lake city, ut). from january through april and again from september through december 2010 (no samples were collected may-august), pediatric patients (up to age 20 years) presenting to the emergency department (ed) at chm, a tertiary pediatric medical center in detroit, michigan, were offered participation in the study if the treating clinician had ordered any testing for viral respiratory pathogens. some admitted patients had specimens collected in the hospital. the protocol required study patients to have one or more of the following signs or symptoms suggesting respiratory infection: fever, cough, sore throat, runny nose, pain or pressure in ears, sinus pressure, and/or sneezing. the study coordinator confirmed with the treating clinician that the patient exhibited the recorded signs or symptoms before patient enrollment into the study. the study was approved by the wayne state university human investigation committee. our laboratory offers 2 rapid antigen tests (rat) based on lateral flow immunochromatographic methods for respiratory viruses: binaxnow rsv (binax, scarborough, me) and quickvue influenza a & b (quidel, san diego, ca). they were performed according to the manufacturers' instructions. for respiratory virus cultures, patient specimens are inoculated into 4 monolayer cell culture tubes: rhesus monkey kidney, hep-2, and 2 mrc-5 (human fetal lung fibroblast cell line; binax, scarborough, me). all except 1 mrc-5 tube are incubated at 36 c and observed daily for the development of cytopathic effect (cpe). if cpe develops, depending on its appearance, the cells are reacted with the appropriate fluorescent antibody (influenza a; influenza b; parainfluenza viruses 1, 2, and 3; adenovirus, or respiratory syncytial virus (rsv); d 3 ultra respiratory screening and identification kit, diagnostic hybrids). the 36 c mrc-5 tube of all respiratory cultures that are older than 3 days and do not show cpe are tested by hemadsorption using guinea pig red blood cells (viromed, minnetonka, mn). hemadsorbing viruses include influenza a and b and the parainfluenza viruses. hemadsorption-positive cultures are tested with the fluorescent antibodies described above, potentially shortening the time to diagnosis. the remaining mrc-5 cell culture is incubated at 32 c. if cpe characteristic of rhinovirus is seen, the culture is signed out as presumptive rhinovirus. these techniques cannot detect coronavirus, human metapneumovirus (hmpv), or human bocavirus (hbcv). viral cultures were monitored 14 days for cpe before being reported negative. the filmarray respiratory panel assay (biofire diagnostics, inc) is a svpcr assay and was designed to detect 21 respiratory pathogens simultaneously, from the same nasopharyngeal (np) swab. freeze-dried reagents for nucleic acid purification, reverse transcription, nested multiplex pcr, and high-resolution melting analysis are contained within a proprietary reagent pouch that is inoculated with the patient respiratory specimen. 13 filmarray respiratory panel testing can identify 21 common and emerging bacterial and viral respiratory pathogens: adenovirus; hbcv; bordetella pertussis; chlamydophila pneumoniae; coronaviruses hku1, nl63, 229e, and oc43; hmpv; rhinovirus and enterovirus (r/e); influenza a viruses a/h1, a/2009 h1, a/h3, influenza b; mycoplasma pneumoniae; parainfluenza viruses 1, 2, 3, and 4; and rsv. as of may 2012, fda clearance had been obtained for all but hbcv. filmarray respiratory panel test results were compared with rat and viral culture results as part of the clinical evaluation of this system. results were analyzed locally for coinfection trends. per study protocol, results of filmarray respiratory panel testing were not shared with treating clinicians. suggested isolation precautions are recommended for specific respiratory pathogens based on methods of transmission to prevent hai. 10, 14 respiratory isolation precautions are recommended for influenza viruses, r/e, b pertussis, and m pneumoniae. 10, 14 contact isolation precautions are recommended for rsv, hmpv, hbcv, and parainfluenza viruses. 10, 14 standard precautions are recommended for coronaviruses and c pneumoniae. 14 dual contact and respiratory isolation precautions are recommended for adenovirus. 10, 14 statistical analysis the pearson c 2 test was used to compare the age-based differences in the detection of r/e, rsv, and hmpv. fisher exact test was used to compare age-based differences between those with a pathogen detected compared with none detected and single and multiple detected pathogens. five hundred three np swabs were obtained from 503 pediatric patients who were offered participation in the study because their physician had ordered testing for a respiratory pathogen. no patient parent/guardian offered participation in the study refused consent. of the 503 enrolled, 499 had valid svpcr array rp results (4 samples did not pass internal quality controls within the assay). there were 300 males (60%) and 199 females. ages ranged from 1 week to 20 years (mean, 2.2 ae 3.2 years; median, 1 year). there were 377 patients aged 24 months (younger children) and 122 aged !25 months (older patients). this age designation was chosen because infants and young children cannot contain their secretions and require close physical contact for patient care, which may lead to an increased risk of transmission of pathogens. the most commonly reported symptoms were runny nose (358/ 499: 72%), cough (342/499: 69%), and fever (332/499: 67%). the median number of reported symptoms was 2 (range, 1-5 symptoms). standard techniques utilizing rat (for rsv and influenza a/b) and viral culture yielded positive results for at least 1 pathogen in 99 of 499 (20%) samples. rat was positive in 66 (63 rsv, 3 influenza a) samples. viral culture was positive in 63 samples (29 rsv; 18 adenovirus; 5 enterovirus; 5 parainfluenza 3; 3 parainfluenza 2; 2 influenza a; and 1 influenza b). rsv was detected by rat (alone) 38 times, by culture (alone) 4 times, and by both rat and culture 25 times. influenza a was detected 1 time in culture (alone) and 2 times by both rat and culture. only 6 samples that tested positive by standard techniques gave negative svpcr array rp results: these included 3 viral cultures positive for adenoviruses, 1 for enterovirus, and 1 for influenza a virus (the last was confirmed by positive influenza a rat). one additional sample positive for rsv by rat was negative by viral culture and svpcr array rp. one patient with a positive rat for rsv had a discordant viral culture that grew only adenovirus. that patient's svpcr array rp identified rsv as well as r/e but not the adenovirus. of the 499 samples tested by svpcr array rp, 344 (69%; 3.4-fold higher than standard techniques) were positive for a total of 408 pathogens (table 1) , including 275 (73%) of 377 specimens from younger children and 69 (57%) of 122 from older patients. this difference is significant (p ¼ .001). excluding coronaviruses, hmpv, and hbcv, which our routine virologic diagnostic assays cannot detect, svpcr array rp detected 318 viruses (3.2-fold higher than standard techniques). at least 1 pathogen detected by standard techniques correlated for at least 1 pathogen detected by svpcr array rp results except for in the 6 cases noted above. only 5 bacterial infections were detected: 4 b pertussis and 1 m pneumoniae. the pathogens most frequently identified by svpcr array rp were r/e in 181 of 344 (53%), rsv in 95 of 344 (28%), and hmpv in 39 of 344 (11%). rsv detection was significantly higher in younger children (95/377 or 25%) as compared with older patients (10/122 or 8%; p .001). frequency of the 3 pathogens most commonly detected by svpcr array rp testing during the study months is shown in figure 1 . fever, as the only qualifying sign or symptom, was the single inclusion criterion for enrollment in only 28 (6%) of all participants having viral respiratory testing ordered by the treating clinician. nine of these 28 (32%) had positive svpcr array rp results. those with positives results included 6 with r/e, 2 with rsv, and 1 with parainfluenza 2. one participant with r/e had coinfection with parainfluenza 3. more than 1 pathogen was identified in 57 svpcr array rp specimens (11% of the total and 17% of those testing positive). of those, 49 (86%) tested positive for 2 and 8 (1.4%) for 3 (fig 2) . multiple pathogens were detected in 49 younger children (13% of the total and 18% of those with a positive svpcr array rp) but only in 8 older patients (6.6% of the total and 11.7% of those with a positive svpcr array rp test). this age difference in the number of coinfections was not significant (p ¼ .277). of those with coinfection, 36 of 57 (63%) would have required combined contact and droplet isolation precautions (gown, gloves, and mask) based on the pathogen combinations identified. combined precautions are also recommended for adenovirus, which was detected in 17 singly infected patients. therefore, 53 of 344 (15%) of those with at least 1 pathogen identified, or 11% of the months. the other pathogens were not tested because their numbers were too small. z rsv detection differed significantly in all children aged < 24 months (combined) compared with those ! 25 months (p value .001). x coronavirus values are combined totals within the age categories and included hku1, nl63, oc43, and 229e. 499 tested, would have required combined isolation precautions (fig 2) . to estimate the theoretical number of children who may have been assigned to the wrong level of isolation precautions, only the rat and svpcr array rp assays had results available in time to impact isolation precaution determinations as culture is significantly slower. thus, only the rat and svpcr array rp results were used in the calculation. only 66 rat were positive compared with the 344 who had at least 1 pathogen identified by svpcr array rp. the difference between the 2 assays is 278. standard testing with rat could have wrongly assigned isolation precautions (either no precautions for a false negative rat or single precautions when there should have been dual precautions (for coinfection) based in increased yield from svpcr array rp) in 278 of those 344 (81%) with a positive test result or 278 of the 499 (56%) total participants. co during the 8-month evaluation of this svpcr array rp at a tertiary care children's hospital, participants were enrolled during the traditional months when respiratory pathogens infect children. this svpcr array rp assay is rapid, takes 2 minutes of hands-on time/sample, and does not require special molecular training for the operator. this svpcr array rp detected at least 1 pathogen in 344 (69%) of the 499 np samples, whereas standard rat and virus culture techniques detected only 99 (20% of the total and 29% of those with svpcr array rp-detected pathogens). this rate is in the middle of the range of other studies using molecular methods for respiratory pathogen detection, which reported positive rates ranged from 46% to 93%. 5,15-18 based on svpcr array rp results, there was a significant difference in the number of children 24 months and younger with a detected pathogen compared with those aged 25 months and greater. this difference may be related to the developing immune system of the younger age group, lack of previous virus exposure during early life, or to possible colonization. 17 those 25 months and older presenting with uri symptoms may have various other non-svpcr array rp tested pathogens causing their symptoms. the fda-cleared svpcr array rp assay package insert reports 87.4% to 100% sensitivity and 94.6% to 100% specificity, based on pediatric and adult data (65% were children 5 years) obtained from the prospective clinical evaluation of the svpcr array rp assay (excluding bocavirus). 19 in our patient population, coinfection with 2 or more pathogens, including the 3 bacteria included in the svpcr array rp, was noted in 57 (17%) of 344 svpcr array rp-positive specimens, with 8 of these having 3 detected pathogens. other investigators have also reported "mixed" viral infection or coinfection in children. one study from finland, utilizing both pcr and diagnostic assays, including serology, noted mixed viral infections in 57 of 293 (19%) samples. in their study, as in ours, respiratory rhinoviruses/ enteroviruses were among the most commonly identified viruses in mixed infection. 16 a study from france found that 21.4% of pcrpositive nasal aspirate samples contained at least 2 viruses. 20 additionally, a german group reported that 16.1% of their pediatric patients with acute respiratory tract infection had positive test results for more than 1 virus. 21 two molecular studies from seattle, wa, detected viral coinfection in 18% of their patients with at least 1 identified viral pathogen 17 and in 23% of their pediatric patients with symptoms of bronchiolitis. 18 neither of these reports suggested that testing to identify respiratory picornaviruses was performed. 17, 18 however, in a multicenter study, mansbach et al reported that 28.9% of infants and children up to 2 years of age with bronchiolitis had multiple pathogens detected, including rhinovirus. 5 the identification of viral coinfection has been associated with differing clinical outcomes. for example, aramburo et al 22 used real-time pcr to detect respiratory viruses in critically ill children with respiratory tract disease and reported that 70.5% of the children sampled had 1 viral pathogen and that 14.5% of these patients had viral coinfections. patients with viral coinfections had higher mortality rates, although this was not statistically significant. 22 in another study of patients with hematologic disorders, no significant differences were noted in presentation or outcome between episodes of febrile neutropenia caused by bacterial infection and those caused by mixed viral and bacterial infections. 23 some combinations of pathogens, especially coinfection with rsv, have been associated with longer length of stay. 5 treatment of infants and young children with uri or bronchiolitis symptoms may not be altered by viral testing or pathogen identification. 2 however, for patients hospitalized with uris, for whom private rooms are not available, cohorting has been recommended. 10 additionally, isolation precautions are employed to prevent transmission of specific pathogens with known methods of transmission (ie, aerosols or contact) to minimize the risk of hai. 10 rsv transmission may be optimally prevented by the use of contact isolation precautions (gown and gloves), whereas spread of rhinovirus and influenza is prevented by droplet precautions (mask). data provided from multiple investigations, including this study, add to the growing body of evidence suggesting that viral coinfections are common in infants and young children with uri symptoms. [15] [16] [17] [18] [24] [25] [26] [27] the clinical significance of the multiple pathogens identified both by quantitative (viral load) and qualitative methods (present study) has been questioned before and has been variously reported to have different degrees of clinical importance. 17, [26] [27] [28] the detection of dead or noninfectious virus particles by molecular assays is theoretically possible, as is the possibility of asymptomatic carriage. 1, 5 for example, the svpcr array rp detects mycoplasma pneumoniae and chlamydophila pneumoniae, which have been reported to persist long after active infection has resolved. 14 the clinical relevance and transmissibility of these 2 agents require clinical correlation. in contrast, b pertussis is thought not to cause prolonged np colonization but may become undetectable, even by molecular techniques, shortly after the characteristic whoop develops. this suggests that positive results for b pertussis may indicate detection of a true pathogen, as was noted in 2 of our patients with coinfections. heininger et al suggested that coinfections of viruses, such as rsv and hmpv, with bordetella spp are rare. 25 if viral coinfection does truly increase disease severity, it may be that multiple infections are overrepresented in study samples from patients seeking evaluations in the ed and especially in those admitted to the hospital. additionally, other agents both known and as yet unknown may also cause uri in children. based on review of the published pediatric literature using molecular techniques to identify respiratory pathogens, the reported rates of coinfection with pathogen combinations that would require combined isolation vary from an estimated 4% to 15% of the total samples tested. 5, 17, 18, 22 of note, combined isolation precautions are routinely recommended for some respiratory viruses, including adenovirus, because of known mechanisms of transmission. 10 this estimated rate of pathogens requiring combined isolation precautions would be even higher if detection of adenovirus alone is included. in our study, considering both mixed and adenovirus infections, 11% of all of the children tested had pathogens requiring both droplet and contact isolation precautions. svpcr array rp detected a large number of pathogens and multiple coinfections in children with uri seeking medical care at our children's hospital. many of these required combined contact and droplet isolation precautions. therefore, our center has continued the use of combined isolation (contact and droplet) precautions for hospitalized children with uri symptoms yearround. this is maintained for all in-patients with uri symptoms for the duration of the illness or until hospital discharge. patients placed in combined isolation are cohorted upon admission when private rooms are not available. although cohorting of patients should be based on symptoms because of the range of pathogens we cannot culture and for which no rapid diagnostic tests exist, the full impact of rapid respiratory testing platforms, such as the svpcr array rp, may allow for more focused isolation and cohorting of patients in the future and needs further study. like many issues in hospital infection control, causation is difficult to prove because increases or decreases in hai rates are multifactorial. hospital epidemiologists at chm track and report hai rates for rsv, as detected by rat or culture, during january through april for annual benchmarking. no other hai respiratory viruses were routinely monitored. for the 3 years prior to initiation of combined droplet and contact isolation (2006) (2007) (2008) , the average rsv hai rate per 1,000 patient days was 0.25 (16 rsv cases; unpublished data). during 2009 to 2011, after the implementation of combined isolation, the rate was 0.15 (9 rsv cases; unpublished data). this difference is not significant (p ¼ .478). however, targeted infection control interventions, including specific viral testing, isolation precautions, and cohorting, have been reported to be associated with prevention of hai and cost savings at other centers. 4 the low number of influenza a strains detected may have reflected the timing of the influenza seasons. during the winter of 2009-2010, influenza peaked between october and december. during the winter of 2010-2011, almost all the influenza occurred during january through march. thus, little influenza was detected by any methodology during our study periods. strengths of this study are the large sample size, the broad age range of enrolled pediatrics patients sampled for the study, and the use of the sensitive molecular method-based detection by svpcr array rp. limitations include that the data are obtained from a single center, that no samples were obtained or analyzed from may to august 2010, and that no further data on the patient's clinical course were recorded after enrollment. as noted above, with most respiratory molecular diagnostic sample testing including this study and others, there is a possibility of pcr tests from respiratory samples yielding positive results that may be due to dead virion detection as opposed to active viral replication. in pediatric patients with uri symptoms, infections with common pathogens, including rhinoviruses, were detected when sensitive molecular assays are utilized. however, those same patients often had negative rat and viral culture results because of limitations in sensitivity and in inherent detection capabilities of these assays. nearly 70% of our patients with uri symptoms (73% of those aged 24 months) had positive svpcr array rp results for at least 1 pathogen. coinfection was present in 11% of all tested and 17% of those testing positive for at least 1 pathogen. because of the pathogens and pathogen combinations detected in 11% of all participants tested, our study findings suggest that combined contact and droplet isolation precautions (gown, gloves, and mask) may be warranted to prevent hai in pediatric inpatients with uri. further studies will be needed to confirm these findings and to assess the effect of combined isolation precautions on prevention of hai in pediatric hospitals. bronchiolitis: too-familiar yet too-mysterious disease of childhood diagnosis and management of bronchiolitis viral testing and isolation of patients with bronchiolitis nosocomial respiratory syncytial virus infections: the cost-effectiveness and cost-benefit of infection control prospective multicenter study of viral etiology and hospital length of stay in children with severe bronchiolitis rapid testing for respiratory syncytial virus in a paediatric emergency department: benefits for infection control and bed management evaluation of an evidence-based guideline for bronchiolitis sustaining the implementation of an evidence-based guideline for bronchiolitis bronchiolitis: recent evidence on diagnosis and management guideline for isolation precautions: preventing transmission of infectious agents in health care settings comparison of two broadly multiplexed pcr systems for viral detection in clinical respiratory tract specimens from immunocompromised children comparison of the idaho technology filmarray system to real-time pcr for detection of respiratory pathogens in children fil-marray, an automated nested multiplex pcr system for multi-pathogen detection: development and application to respiratory tract infection summaries of infectious diseases two-year prospective study of single infections and co-infections by respiratory syncytial virus and viruses identified recently in infants with acute respiratory disease respiratory picornaviruses and respiratory syncytial virus as causative agents of acute expiratory wheezing in children multiple versus single virus respiratory infections: viral load and clinical disease severity in hospitalized children multiple viral respiratory pathogens in children with bronchiolitis filmarray respiratory panel instruction booklet. salt lake city comparison of multiplex pcr assays and conventional techniques for the diagnostic of respiratory virus infections in children admitted to hospital with an acute respiratory illness frequent detection of viral coinfection in children hospitalized with acute respiratory tract infection using a real-time polymerase chain reaction role of real-time reverse transcription polymerase chain reaction for detection of respiratory viruses in critically ill children with respiratory disease: is it time for a change in algorithm? frequency and clinical outcome of respiratory viral infections and mixed viralbacterial infections in children with cancer, fever and neutropenia single versus dual respiratory virus infections in hospitalized infants: impact on clinical course of disease and interferon-gamma response bordetella pertussis and concomitant viral respiratory tract infections are rare in children with cough illness clinical disease and viral load in children infected with respiratory syncytial virus or human metapneumovirus multipathogen infections in hospitalized children with acute respiratory infections respiratory syncytial virus infections in hospitalized infants: association between viral load, virus subgroup, and disease severity the authors thank lynn semproch for providing the chm epidemiology data for this analysis. key: cord-266667-6isk8jgj authors: fix, gemmae m.; reisinger, heather schacht; etchin, anna; mcdannold, sarah; eagan, aaron; findley, kimberly; gifford, allen l.; gupta, kalpana; mcinnes, d. keith title: health care workers’ perceptions and reported use of respiratory protective equipment: a qualitative analysis date: 2019-06-07 journal: am j infect control doi: 10.1016/j.ajic.2019.04.174 sha: doc_id: 266667 cord_uid: 6isk8jgj background: little is known about health care workers’ (hcw) perceptions of, or experiences using, respiratory protective equipment (rpe). we sought to characterize their perceptions and identify reasons underlying inappropriate use. methods: we conducted 12 focus groups with nurses and nursing assistants at 4 medical centers. we analyzed the thematic content of 73 discrete “stories” told by focus group participants. results: we identified 5 story types surrounding rpe use: 1) policies are known and seen during work routines; 2) during protocol lapses, use is reinforced through social norms; 3) clinical experiences sometimes supersede protocol adherence; 4) when risk perception is high, we found concern regarding accessing rpe; and 5) hcws in emergency departments were viewed as not following protocol because risk was ever-present. discussion: hcws were aware of the importance of rpe and protocols for using it, and these supported use when protocol lapses occurred. however, protocol adherence was undermined by clinical experience, perceived risk, and the distinct context of the emergency department where patients continually arrive with incomplete or delayed diagnoses. conclusions: protocols, visual cues, and social norms contribute to a culture of safety. this culture can be undermined when hcws experience diagnostic uncertainty or they mistrust the protocol and instead rely on their clinical experiences. advanced respiratory protective equipment (rpe), like powered air-purifying respirators and n95 respirators, are critical for protecting health care workers (hcws) from contracting and spreading airborne infections. proper rpe use reduces risk, yet existing research documents low adherence. 1 moreover, the emergence of pathogens such as ebola and severe acute respiratory syndrome (sars), has raised awareness of the importance of respiratory protection. 2, 3 although much work has been done to understand how discomfort (eg, facial pressure, shortness of breath) might affect use, [4] [5] [6] [7] [8] less is known about how beliefs, perceptions, or work experiences might influence protocol adherence. understanding what contributes to a system-level safety culture can ensure that when more significant pathogens are present, and increased n95 use is needed, barriers to use can be systemically addressed. hcw adherence to respiratory infection control guidelines, including vaccinations, are known to be influenced by personal and contextual factors, such as knowledge gaps, perceived risk, ethical and legal concerns, and economic issues 9, 10 health behavior theories, such as the health belief model, 11 have been used to examine adoption of health-related behaviors. 12 health belief model constructsperceived severity, susceptibility, benefits and barriers to the health behaviors, perceived threat, cues to action, self-efficacy, and demographic factors-may inform whether protective action is taken. 13 the health belief model has been previously used to understand use of respiratory protection. 14, 15 these studies found that perceived seriousness and perceived susceptibility were major factors in hcw decisions to wear respiratory masks during a sars outbreak. however, there may be other unexplored factors impacting respiratory protection use. we therefore sought to characterize perceptions of rpe, identify reasons for use, and examine how work routines might impede or facilitate protocol adherence. we used a qualitative study design to examine hcw's perceptions and reported rpe use. we focused on registered nurses (rns) and nursing assistants (nas) because they provide frontline care, spend significant time with patients, are frequently exposed to infectious agents, and thus are more likely to require rpe. 1, 16 this design facilitates identifying previously unknown issues from the participants' perspectives. importantly, whereas some responses may not be "true," the perception of their veracity may still inform behaviors and highlights the use of our qualitative approach. for example, transmission routes described by an hcw may not be biologically plausible, yet this understanding may inform rpe use. we recruited from hospitals in the northeastern and midwestern united states (1 veterans health administration and 1 academic medical center per region). local contacts at each hospital provided eligible participants from adult inpatient medical, surgical, and intensive care units, and emergency departments (ed) information about our study. focus groups were restricted to na only or nurse only; however, they could provide patient care in any of the targeted recruitment units mentioned earlier. focus groups often had more than 1 nurse or na from a particular unit. originally, we planned 2 focus groups per hospital, 1 each with nas and rns. however, an international ebola outbreak spurred an additional focus group at each hospital of rns who had ebola prevention training. the focus group guide (see appendix), informed by the health belief model, covered experiences using rpe (cues to action), reasons for use (perceived benefits and barriers), experiences with rpe (perceived seriousness and susceptibility), descriptions of situations when masks were not worn (motivating factors), and comfort and usability (motivating factors). we brought n95s and surgical masks to the focus groups. we focused questions and analysis on n95s. after obtaining informed consent, focus groups were audio-recorded and transcribed. participants completed a survey about their employment and whether they had been fit tested or received rpe training. study procedures were approved by the hospitals' institutional review boards. we used a qualitative analytic strategy, initially guided by the health belief model. however, during data review, we noted the health belief model, which is a useful heuristic to organize the data, was insufficient to fully capture the rich narrative content of the data. we noted data were comprised of short stories relating to events surrounding rpe use. to take advantage of this data and reduce disaggregation of the findings, we organized the data into "story units," defined as segments of text with a beginning, middle, and end. 17 our team subsequently analysed transcripts looking for discrete "story units." two team members independently reviewed each transcript and delineated the stories using a template. each templated story was given a title, summary, and discussed by the full team. we then conducted an inductive thematic analysis of these stories, sorting them into different story types. we noted when participants brought up droplet or contact precautions. nurses with advanced training* 5 3.5-23 12 nursing assistants 2 1-3 vha, veterans health administration. *the focus groups were conducted at a time of heightened awareness of ebola. these nurses received advanced training in triaging and caring for patients with potential ebola. we conducted 12 focus groups (table 1) . across the focus groups, we identified 73 discrete stories about rpe use, which we organized into 5 categories: 1) participants knew their sites' rpe policies and protocols. they described visual cues, such as signs resulting from these policies encountered during work routines that promoted rpe use. 2) sociocultural norms reinforced rpe use, particularly during unexpected events. 3) hcws used their clinical experiences to determine use, sometimes opting to wear more rpe than required. 4) additionally, risk perceptions varied by rural and urban contexts. in urban areas, for example, hcws who perceived exposure to many high-risk patients reported limited access to rpe. finally, 5) perceived underuse in the ed was attributed to the constant presence of patients with incomplete or delayed diagnoses. further descriptions of each category are in the following paragraphs. following hospital rpe protocol was considered part of the job. when asked about not wearing rpe when required, a site 3 participant replied, "that's not an option." participants specified clinical indications that necessitated rpe, including a medical evaluation to "rule out" tuberculosis (tb), ebola, sars, middle east respiratory syndrome, meningitis, or upper respiratory infections. participants' stories included a variety of cues prompting rpe use, including door signs on patient rooms, personal protective equipment carts in front of patient rooms, documentation in the electronic medical record, and patients being in a negative air pressure room. a site 1 participant recounted 2 common cues, signs, and nurse reports: "we have a big sign on the door that says 'airborne precaution' and it will tell you some things that you have to wear, so when it says airborne precaution you know that you have to wear a mask and things like that. and on report, before we get to the room, you need to get report from the other nurse that was taking care of that patient so the report will tell you. . .what to do before you get in." several stories described scenarios highlighting how it was socially acceptable to identify lapses in following the rpe protocol. wearing rpe was consistently recognized as "one of the things that you have to do," despite rpe being "suffocating" and "claustrophobic." these feelings could be acute when the nurse had an upper respiratory infection, which meant "you actually can't breathe at all [with rpe on]." despite discomfort, a common sentiment was that rpe was protective, as a site 2 na said: "i wouldn't wanna wear [rpe] all the time. but they're manageable, and i'd rather have them on than have them off." the safety culture could be seen in practice. when lapses in protocol adherence occurred, hcws were enculturated to enforce the policy. at site 1, several participants told a story about a non-english speaking patient with tb who became hypoxic and disoriented, coughing up blood-tinged sputum as he unexpectedly emerged from his isolation room. several hcws quickly gathered, and whereas some began providing direct care, others, who sensed the risk of infection, began yelling to colleagues, "put a mask on! put a mask on!" in another story, site 4 participants described how a food service worker walked into a negative pressure room without a respirator, despite an "airborne precautions" door sign. after informing this individual, the nursing staff reported the event to supervisors who helped organize a respiratory precaution training for food service staff. beyond protocols, participants evaluated patient behaviors and symptoms to determine whether to wear rpe. this meant they might decide to use rpe even if protocol specified droplet or no precautions. often, patient symptoms served as a cue to don rpe; "yeah, i've put [rpe] on if someone is coughing so forcefully that it sounds like one of their organs is gonna come out. . .." [site 4] similarly, several nurses at site 2 recounted a series of symptoms that prompted "clinical judgement to kick in." one participant described likely exposures to tb because of patients being misdiagnosed with pneumonia: "it took a couple of events where i was exposed [to a patient who had an active, but undiagnosed airborne infection] and then i was like okay, i'm not gonna, you know, make that mistake again." now, with symptomatic patients, she dons rpe even when the working diagnosis does not require airborne precautions. historical, personal experiences also framed current use. a site 1 nurse described her history wearing protective equipment: "hiv had just started to come out in 1983, 84, and so we were trained not wearing gloves when you would do a bed bath. there were no gloves. . . . you would just clean your patient and wash your hands well afterward, so we had just been introduced to gloves as hiv came out in the '80s, early '80s, so the masks were, geez, like i can't wear that [laughing] . . . like when that was introduced it was a whole learning curve . . . and now we have this whole-body thing. a colleague noted that in light of current outbreaks, rpe use might increase, "it's not just ebola anymore. . .there's a lot more viruses coming down the pike. . .. we could end up wearing masks all the time at work." perceptions of risk, need for rpe, and access to equipment vary by context we found a relationship between risk perceptions, perceived access to rpe, and local context. participants reported varying degrees of exposure to patients with potential airborne infectious diseases, which in turn informed their perception of individual risk. for example, at sites treating more rural populations, participants reported few encounters requiring hcws to don airborne precautions and a lower perception of risk of exposure. they also described rpe as plentiful and accessible. a nurse at site 2 described access to rpe, saying "they're everywhere." at another site serving rural areas, several participants described the multiple ways of ensuring equipment availability: in contrast, participants from urban sites serve populations with a higher prevalence of respiratory infections such as tb and perceive a greater risk of exposure when compared with the rural colleagues. as a nurse from urban site 1 described, rpe was down a long hallway, "at the end of the universe." she noted having a "small face" requiring a small-sized mask, which was infrequently stocked. another nurse at site 4 stated, ''they keep them [in another area] because they know how expensive they are,'' and further explained, "some people go to grab the yellow masks for droplet precautions and they might put on the n95 respirator for a droplet" perceiving that the hospital was trying to prevent hcws from mistakenly using a more expensive n95 instead of appropriate droplet precautions. uncertainty about diagnoses for patients entering the health care system through the ed participants described receiving inaccurate or delayed clinical information, for example, not knowing the patient had a potential airborne infection. this was especially the case for nurses working in the ed, who described distinctly different experiences. one site 2 na noted, "it's a little scarier in the er [emergency room], just 'cause you don't know what they're coming with." similarly, nurses from other sites described the ed as different, too. a site 3 nurse reported that when transferring a patient with a diagnosis requiring rpe from the ed, only the accepting department wore protection. she reasoned the ed staff not wearing rpe by saying, "they've kind of already been exposed to it, then it's too late." the ed was perceived as a place with less use of rpe, both because diagnosis was unknown, and this was attributed to ed staff being less likely to follow protocol. we conducted one of the few large, in-depth, qualitative studies of rpe use in hospital settings. 18, 19 in 12 focus groups, spanning 4 hospitals, with rns and nas, participants described 2 types of nonadherence. one was of rapidly evolving situations in which hcws were caught off guard, and unable to immediately don rpe. the other was related to an insufficient safety culture. importantly, each of these is modifiable to some extent through enhanced communication and multidisciplinary teamwork. the first type of rpe protocol nonadherence was not hcw oversight or ignorance, but rather unexpected actions by patients and other staff. illustrating this type was the story about a distressed patient with tb emerging from his negative pressure room without warning. hcws sprang to action to assist the patient, but without rpe. nearby colleagues, observing the potentially dangerous situation, quickly reminded the first responding hcws of the urgent need to don masks. another example of this type was a food service employee, apparently oblivious to precaution signs, walking into a patient room without the required rpe. similarly, hcws requested additional training for food service employees. these instances suggest the hcws felt empowered to speak up to colleagues when safety standards were not met. this indicates a pervasive safety culture, in which following protocols is habituated. this culture is created, as we and others have found, 20 through trainings, leadership addressing safety concerns, peer influence, and tangible resources like accessible equipment. hcws appear to have the training to identify "moments of risk" and feel empowered to take immediate action to mitigate them. this type of culture and hcw empowerment has been associated with robust patient safety practices. 21, 22 achieving the appropriate cultural among hcws, however, has been shown to be challenging in hospital systems perhaps undermined, as we found, by inaccessible equipment. the other type of nonadherence we found indicated limitations in the safety culture. we found 3 problematic areas, as well as indications of how to address. in the first, some hcws did not trust the protocols and safety systems in place. instead they relied on their clinical experience to determine what protection to wear. several hcws we spoke with talked about wearing n95s when the protocol specified a surgical mask. this was because they suspected, based on their clinical experience, that the patient might later be diagnosed with a respiratory infection. one nurse stated: "i'm not gonna, you know, make that mistake again." this was attributed to, in part, experiences that hcws had in which they had initially worn droplet protection, only to learn that the patient was later diagnosed with an airborne infection, which would require a higher level of rpe. clinical experience has been shown to improve adherence, 23 yet it may also spur overuse. in our data, when hcws did not trust the working diagnosis they relied on their own clinical judgement, which led them to use a higher level of rpe protection than the protocols specified. this behavior can result in variable rpe use owing to the different levels of experience across staff. further, inappropriate overuse may desensitize people to the importance and value of rpe, and send a confusing, and potentially alarming, message to others. overuse of rpe may also result in equipment being unavailable when needed, as we and others have found. 19 moreover, availability is an important factor in adherence. 23 when hcws do not trust the diagnosis, huddles could help team members communicate about risks, address potential concerns, and lead to consistent and appropriate rpe use. 24 team huddles are a proven management and communication approach 25 that could be used to review emerging patient diagnostic data and discuss with team members how to best use rpe for the unique situation. this deliberate review and clarification of risk levels may lead to hcws' increased trust in infection control systems and belief that the hospital is motivated not by finances, but instead hcw safety. a second problem area was the perception of heightened risk and the related feeling of inadequate rpe availability. some hcws believed that their site had many high-risk patients, particularly those in larger facilities in dense urban areas. in contrast, hcws at sites that reported that there were few high-risk patients, described plentiful, accessible equipment. other hcws reported the hospital not having their specified mask size or that rpes were locked away, leading study participants to speculate that the hospital was trying to save money by limiting access to n95 use to discourage inappropriate use. prior research has documented that hcws in larger, more urban hospitals are at greater risk of respiratory infections, especially during outbreaks. 26 the relationship between site type and risk of infections may be further complicated by risk perceptions. the third problem we found related to the unique circumstances in eds. patients coming into the ed arrive without a diagnosis, which puts hcws at greater risk of exposure to infectious agents. yet, perplexingly, this seems to have desensitized these hcws. some hcws reported that even after an ed patient had received a diagnosis warranting use of rpe, ed staff might continue to forgo rpe, because, as one hcw noted, the staff believed they had "already been exposed." hcws working in the ed may perceive that exposure risks are omnipresent, with rpe being unable to protect from the myriad of potential exposures. this is problematic because these hcws may habituate to not wearing rpe when protocol requires use. other research has shown lower adherence to personal protective equipment, including n95s, among hcws in eds. 23 our findings were consistent with several domains in the health belief model. 11 for example, we found that hcw's desire to wear rpe may increase in the presence of symptomatic, but undiagnosed, patients, a feature of perceived susceptibility. rpe use was also informed by perceptions of the seriousness of patient symptoms or disease. additionally, the health belief model may provide guidance for strengthening safety systems, such as providing cues to action (eg, signs, carts) to help initiate donning rpe. however, whereas the health belief model was useful in developing the focus group guide, and used to guide parts of the analysis, it had limitations; our additional use of an inductive analytic approach was useful where the health belief model was lacking. for example, we encountered stories around rpe availability or rapidly developing emergent situations that may have precluded hcws' abilities to adequately process the severity and susceptibility. the health belief model was originally developed with the individual in mind to understand what influenced their likelihood of getting vaccinated. this origin helps explain why it was limited for explaining hcw behavior because hcws are enmeshed in complexities of health care facilities and systems. workplace culture, training, resource constraints, and clinical experiences create a multilayered work context above and beyond the individual perceptions of risk, susceptibility, and threat. our study has limitations. it was conducted at 4 hospitals in 2 regions of the united states, and not designed to determine differences among settings or differences by unit. findings related to the unique context of the ed were emergent and not part of our original study design, thus, more work needs to be done to understand ed microculture. study participants were limited to rns and nas; other clinicians, staff, and patient and family perspectives were not represented. the timing of our study was unique given the ebola outbreak and therefore increased sensitivity to rpe use. therefore, we may have heard greater concerns about rpe availability and use. moreover, our data collection method (focus groups) may have led to social desirability biases, with reluctance to report nonadherence. recent ebola and sars outbreaks remind us that a large-scale pandemic is always possible. adherence to respiratory precautions may become critical with little advanced notice. although government and public health agencies should continue to develop data-driven protocols, hospitals need to assess their own unique context, 27 including local norms, particularly in the ed where patients arrive without a diagnosis or hcws may not fully trust the protocols for rpe use. our data provide insight into reasons for rpe nonadherence; importantly, these are to a large extent modifiable. early appraisal of facility-level-or ward-level in the case of the ed-vulnerabilities in patient safety culture surrounding rpe use could be a useful strategy for ensuring improved adherence during high incidence respiratory illness seasons when rpe use is critical. supplementary material associated with this article can be found in the online version at https://doi.org/10.1016/j.ajic.2019.04.174. behind the mask: determinants of nurse's adherence to facial protective equipment sars among critical care nurses appraisal of recommended respiratory infection control practices in primary care and emergency department settings development and initial validation of the respirator comfort, wearing experience, and function instrument health care workers' reported discomfort while wearing filtering face-piece respirators discomfort and exertion associated with prolonged wear of respiratory protection in a health care setting respirator tolerance in health care workers canadian agency for drugs and technologies rapid response reports. wear compliance and donning/doffing of respiratory protection for bioaerosols or infectious agents: a review of the effectiveness, safety, and guidelines. ottawa on: canadian agency for drugs and technologies in health influenza vaccination in healthcare workers: a comprehensive critical appraisal of the literature perceived risk of tuberculosis infection among healthcare workers in swaziland health belief model health behavior and health education: theory, research, and practice social learning theory and the health belief model the use of facemasks to prevent respiratory infection: a literature review in the context of the health belief model family physicians' experiences, behaviour, and use of personal protection equipment during the sars outbreak in singapore: do they fit the becker health belief model? factors influencing nurses' compliance with standard precautions in order to avoid occupational exposure to microorganisms: a focus group study the narrative structure as a way to gain insight into peoples' experiences: one methodological approach working experiences of nurses during the middle east respiratory syndrome outbreak current practices and barriers to the use of facemasks and respirators among hospital-based health care workers in vietnam a multilevel neo-institutional analysis of infection prevention and control in english hospitals: coerced safety culture change? mistake-proofing healthcare: why stopping processes may be a good start patient safety: a literative review on the impact of nursing empowerment, leadership and collaboration impact of the 2009 influenza a (h1n1) pandemic on canadian health care workers: a survey on vaccination, illness, absenteeism, and personal protective equipment communication huddles: the secret of team success huddle up! the adoption and use of structured team communication for va medical home implementation emergency department response to sars behavioral science at the crossroads in public health: extending horizons, envisioning the future key: cord-273748-xy4f5kon authors: armijo, priscila r.; markin, nicholas w.; nguyen, scott; ho, dao h.; horseman, timothy s.; lisco, steven j.; schiller, alicia m. title: 3d printing of face shields to meet the immediate need for ppe in an anesthesiology department during the covid-19 pandemic date: 2020-08-04 journal: am j infect control doi: 10.1016/j.ajic.2020.07.037 sha: doc_id: 273748 cord_uid: xy4f5kon anesthesia providers are at risk for contracting covid-19 due close patient contact. proper personal protective equipment (ppe) use is critical to providing a safe environment and to minimize the risk of contagion. during the covid-19 pandemic, a series of supply chain issues, constant changes in ppe use policy, and higher demand for ppe led to shortages in ppe, specifically n95 masks and face shields. implementation of decontamination protocols successfully allowed n95 mask reuse but, required masks to be unsoiled. face shields not only act as a barrier against the soiling of n95 face masks, they also serve as more effective eye protection from respiratory droplets over standard eye shields. the university of nebraska medical center produced face shields using a combination of 3d printing and assembly with commonly available products. approximately 112 face shields were constructed and made available for use in 72 hours. importantly, we created and implemented a simple but effective decontamination protocol, which allowed reuse of the face shields. these methods were successfully implemented for in-house production of face shields used at tripler army medical center (tripler amc, hawaii). the effectiveness of the decontamination protocol was evaluated using the average log(10) reduction in colony counts for escherichia coli atcc 8937 and staphylococcus aureus atcc 25923 from the american type culture collection (atcc, manassas, va). in this manuscript, we present our detailed protocol and supplies needed for printing 3d face shields to enable the rapid production of this product by individuals with little to no 3d printing experience, in times of urgent need. (sars-cov-2) was first isolated in human airway epithelial cells from a cluster of patients with pneumonia of unknown etiology in december 2019 from wuhan, china [2] . the novel virus has since spread to every continent, except for antarctica, infecting greater than 1.5 million people and causing greater than 170,000 deaths as of today. it is estimated that millions of americans will get infected by the sars-cov-2 virus that causes coronavirus disease 2019 and that 40% of the healthcare workforce will be infected and removed from the workforce due to exposure to the virus primarily through respiratory droplets emitted by patients [3, 4] . anesthesia providers are at increased risk for exposure because of their primary role in airway instrumentation for symptomatic and asymptotic covid-19 patients during diagnostic, therapeutic, and surgical procedures. 5 surgical masks, the standard personal protective equipment (ppe) before the covid-19 outbreak for anesthesia providers, do not offer satisfactory protection from covid-19 during close patient interaction, partly due to the risk for aerosol generation at the time of intubation. current literature indicate that surgical masks provide insufficient protection against inhalation of viral particles that exist in both respiratory droplets and aerosolized sub-micron particles generated by infected patients [6] . to overcome this challenge, stringent policies and appropriate use of ppe, such as face shields, safety glasses, and n95 masks, are indicated for providers performing aerosol-generating procedures [7] . n95 filtering face piece respirators (ffr) and powered air-purifying respirators (papr) are a more sophisticated ppe that provides full face and body coverage, respectively, enhancing the level of protection against aerosolized particles. however, there are several challenges associated with the continuous use of ppe, especially for papr and ffr, including the limited supply chain due to the high demand, communication barriers between provider and patient, and discomfort after long-hours of wear [8] [9] [10] . therefore, extending the use of n95 masks, as recommended by the cdc, is an appropriate and suitable alternative in a resource-constrained environment, in which the use of papr and ffr is not practical [11] . with the fast development of the covid-19 pandemic and the incredibly high transmission rates of sars-cov-2, shortage of ppe has become one of the greatest and most concerning challenges among healthcare professionals. high cost, limited availability, low storage stocks to meet surge capacity, and limited capabilities for reuse of ppe all contribute to unavailability. additionally, changing recommendations of appropriate ppe use rapidly evolved in response to the pandemic, producing previously unused supply chain requests [5, [8] [9] [10] . the cdc recommends the implementation of procedures that extend the use of n95 masks 11 to combat the shortage of ppe. this sentiment is echoed by a joint position statement supported by the american society of anesthesiologists (asa), anesthesia patient safety foundation (apsf), american academy of anesthesiologist assistants (aaaa) and american association of nurse anesthetists (aana). 5 one strategy to mitigate the soiling of n95 masks and extend their use is the addition of a face shield that is capable of withstanding decontamination. the physical barrier provided by the face shield provides an added layer of protection of the n95 mask and the face of the provider from respiratory droplets. it prevents the n95 from becoming soiled, allowing for prolonged use. in response to the covid-19 pandemic, the university of nebraska medical center (unmc), department of anesthesiology, mandated that anesthesia providers use face shields during patient care to extend the life of n95 masks and adequately protect providers from infection with sars-cov-2. this mandate required the immediate procurement of 112 face shields for approximately 60 clinical providers working at any one time. our goal was to meet the immediate demand for an increased level of provider protection by providing face shields to reduce viral transmission to the provider. the face shields also prevent the soiling of n95 masks, allowing for reuse with a previously developed ultra-violet radiation sterilization protocol recently approved by cdc/niosh [12] . due to the high demand and low supply of commercially produced face shields, unmc turned to in-house 3d printed face shields using publicly available resources. using this strategy, unmc was able to quickly and efficiently produce 112 face shields in approximately 72 hours using four relatively inexpensive and readily available 3d printers. the face shields were deployed for use by our clinical anesthesia providers the very next day, along with a sterilization protocol that allowed for the reuse of the face shields. the methods developed by unmc as described in this paper was also successfully replicated by the 15th maintenance squadron (15th wing airmen joint base pearl harbor-hickam) and the combat logistics battalion 3 marines (marine corps base hawaii) to rapidly produce and supply face shields to healthcare providers (nurses, medics, physicians, intensivists) at tripler army medical center (tripler amc, hi). they were able to produce approximately 100 face shields in 72 hours with follow-up plans to equip greater than 1000 military and military associated healthcare providers and first responders on the island of oahu. all the information we used to make the face shields was readily available from various sources in the public domain. however, we had to overcome several significant, time-wasting challenges to produce a final, working product. first, we were limited in materials acquisition, to only using locally available materials and previously acquired equipment. secondly, we needed to understand and produce a product that had the appropriate dimensions not to impede our providers in clinical care. finally, we had a significant learning curve to overcome a significant learning curve to produce face shields without prior 3d printing experience. consequentially, we are providing a complete step-by-step instructional guide to producing 3d printed face shields rapidly. our protocol is specific to producing a face shield that is sized appropriately to not interfere with commonly performed procedures, such as endotracheal intubation, and are reusable after decontamination. however, the methods we provide can be used to produce and decontaminate face shields for general use at all treatment facilities. additive manufacturing, or what is commonly referred to as 3d printing, is a fabrication process in which layers of material are added successively to form the desired object. methods of additive manufacturing fall under several different categories, such as filament deposition manufacturing (fdm), also known as fused filament fabrication (fff), stereolithography (sla), digital light processing (dlp), selective laser sintering (sls), or multi-jet fusion (mjf). the key similarity among the methods is the process by which layer-by-layer an object is built through the addition of material. while the same object may be created using any of the methods mentioned above, each has its strengths and limitations [13] . for all 3d printing platforms, the electronic file of the object to be printed (commonly a stereolithography or .stl file) can either be created by the user or downloaded from the shared sources on the internet. in order to print an object, the electronic file must first be loaded into the printer software, and potentially altered to be compatible with the specifications of the printer. a major consideration is the printing platform to use. printers used for fdm and dlp are commonly used desktop-sized printers. of these, fdm is the most frequently used 3d printing platform for non-industrial applications because it is relatively affordable in both the printer and the required thermoplastic filament. fdm printing platforms offer both low-cost filament use and often a more substantial build plate compared to a dlp platform, enabling fdm printers to produce larger or more objects in one run. thus, this was our platform of choice. a significant disadvantage of fdm is that it results in individual layers of a thermoplastic material that, while fused, may not be air-or watertight. dlp printing utilizes a digital projector screen to flash images of the object on to photosensitive resin in order to cure the resin layer by layer. this process results in objects with the potential for higher-layer resolution and are solid pieces that are air and watertight. the authors recognize that all fdm prints generated for the headband of the face shield are not watertight, allowing water and air to pass through them to some degree. this would make uv sterilization or a simple wipe down with anti-bacterial/viral wipes inappropriate and ineffective. given this information, we developed a decontamination protocol that utilized a dilute bleach solution that would allow penetration into any of the pores that are generated in the 3d printing process and permit the reuse of the face shields. the solid headband and chin piece of the face shield we created were 3d printed via fmd, while all other materials, including the transparent face guard, were purchased commercially, and then used to construct the face shield ( table 1 ). the fdm fabrication process, even with a clear pet filament, does not allow for the type of uniformity and consistency that would permit the creation of a truly clear shield that allows good visual acuity for the wearer. fdm filament types include polylactic acid (pla), acrylonitrile butadiene styrene (abs), polyethylene terephthalate (pet). pla requires lower printing temperatures (200-210ºc) and has less warping than abs or pet but is more brittle. abs has higher printing temperatures (230-255ºc) and more durability, but is more prone to warping and can generate toxic gas fumes during printing. pet has a moderate printing temperature (220-235ºc) with durability similar to abs with the ease of use similar to pla. however, it absorbs water and requires additional care when storing the filament. nylon is very durable and is a high-temperature (240-260ºc) filament. while other thermoplastic filaments are available, the need for high-speed and low-cost prompted the use of pla in the current protocol. we chose pla as our printing material due to the fact that the material was readily available, we were very familiar with its use, and the material was low-cost. moreover, pla has excellent printing properties, allowing a fdm printer to print at very high speeds for the make and model (150mm/sec on a prusa mk3 and/or mk3s printer). after careful consideration, we chose to use a prusa i3 mk3s model printer for our 3d face shield printing needs. this model of printer is relatively low-cost (approximately $600), handles pla filament well, and has sufficient printing surface area. additionally, many files are available in the public domain that are designed for use with this printer, thus lowering the barrier for production for individuals who may have little or no 3d printing experience. the specifications for the computer used for designing, modeling, processing, and printing of the .stl file depends on the 3d printing software used. for the face shields printed at unmc, we used a standard dell desktop (xps) computer running slic3r software ( table 1 ). the processed .stl file was then saved to an sd card, and the sd card inserted into the prusa 3d printer for printing. a wide array of software options is available, ranging from relatively simple such as google sketchup (free software) to highly complex such as autodesk autocad. mid-range software includes blender, autodesk maya, and solidworks. as complexity increases, the computer requirements also increase. for example, google sketchup requires a 2.1+ghz cpu and 4gb ram, while autodesk autocad requires, at minimum, an intel pentium 4 processor with 8gb ram. due to the need to transfer files from computer to 3d printer, downloading and installation of software, downloading of .stl files, there may be limitations/challenges to producing face shields at government and military installations, treatment facilities, or hospitals with secure networks that do not allow for easy transfer of files from computer to printer by an external drive. additionally, at these locations, there may be restrictions on acquiring or installing 3d printing software onto network computers. the successful production of a 3d printed face shield will require the following steps: a) creating or obtaining the electronic file for the 3d printed parts; b) printing the face shield parts ( figure 1 ); and c) assembling the face shields with the additional required supplies. first, one must either make or find the file of the idealized model of the desired object. the .slt files used in this paper are located on the prusa face shield website (https://www.prusaprinters.org/prints/25857-prusa-face-shield), under files. this file is optimized for use in the prusa printer and thus would require minimal, if any, modifications by the user to print a quality product. once the .stl file was obtained, it was loaded onto a computer capable of running the slicer software. the slicer software takes the 3d virtual model and determines the process required for the printer to produce the object layer by layer. the slicer printer software can assist in setting the appropriate speed, layer height, and generation of tool paths (the path that the printer extruder follows while printing) for the 3d printer being used. unlike traditional ink printers, where most settings are universal and ink pages would be printed the same regardless of the printer used, 3d printers will require unique modifications based on the model and brand of printer used. the headband print file was adjusted using slicer software to control speed, layer height, support material and the use of other supporting materials. using the prusa rc3 quattro file, a .gcode file was produced that would result in an optimized print speed. using and 0.2mm layer height, 2 outer layers and 3 layers for top and bottom layers along with 0% infill, a stack of 4 head and lower pieces could be printed in 7.5 hours. this print file also utilized a raft to provide optimum adhesion to the build plate give the small amount of contact area this design has with the build plate. no support material is used as the chamfered undersides of the headband allow the printer to successively print layers vertically without issue. prepare all components of the face shield for assembly. figure 1 contains the terminology of the face shield components, whereas figure 2 depicts a pictorial description for the initial face shield assembly. 1. remove the printed headbands and chins (item 7) from the printing deck of the 3d printer. separate into individual components. 2. using the face guard template from the prusa website, item 7 (www.prusa3d.com), mark the location of the needed holes in the clear pvc binding cover (item 3) that will be used for the face guard, using a permanent marker. 3. using a standard hole punch (item 5), punch the holes marked in the face guard. our choice to utilize a high speed and low cost fdm printer with pla, had a known result of leaving small pores present in the final 3d printed product, making the use of uv light sterilization not possible. to circumvent this challenge, we created a liquid sterilization protocol that would allow reuse of our face shields. in brief, the face shields were dissembled, placed briefly in a dilute bleach solution, and allowed to be air dry. when dry, the clear face guard was wiped to remove any spots, and the face shield reassembled for use. our detailed decontamination protocol is included in appendix a. the surface of each face shield part was cleaned by wiping surfaces with caviwipes (metrex, orange, ca) followed by 70% ethanol prior to spiking. following drying, spots to be inoculated were marked with permanent marker. subsequently, 10 µl of bacterial concentration was applied to each marked spot. as a positive control, organism suspensions were inoculated to each face shield part, allowed to dry, and swabbed without decontamination. pbs was inoculated to each part as a negative control. the droplets were left to air dry for 1 hour. each face shield part was disinfected according to appendix a. after adequate drying, a cottontipped swab (puritan medical products company, guilford, me) was used to sample each marked spot. swabs were moistened in sterile pbs and the area was swabbed using a firm sweeping and rotating motion. organisms were enumerated using the spread-plate technique on ba plates. the plates were incubated at 37°c for 20-24 hours. experiments were repeated five times per face shield part (head band, head piece, face shield) and organism (e.coli, s. aureus) for a total of 30 experiments not including positive and negative controls. decontamination effectiveness was evaluated using the average log10 reduction in colony counts. to assess the effectiveness of the appendix a decontamination protocol, we inoculated bacterial suspensions of e. coli atcc 8937 and s. aureus atcc 25923 directly onto each part of the face shield unit. all positive organism and pbs controls were as expected. the decontamination protocol effectiveness against e. coli was greater than s. aureus. two-spiked e. coli spots exhibited growth, one colony each, whereas five-spiked s. aureus spots had characteristic growth. e. coli was observed on the face guard piece, s. aureus was detected from the chin piece and face guard. no organisms were recovered from the head bands. overall, the decontamination protocol was highly effective against both e. coli and s. aureus, achieving a ≥ 4 log10 (99.99%) reduction in colony counts for every replicate. the masks we created are comparable and sometimes superior, to standard commercially available face shields, in terms of the protection area and coverage (figure 3) . a known limitation of our face shield design is the gap between the clear shield and the forehead of the wearer. this space is usually occupied by a foam barrier present in several commercially available face shield models. while this foam provides comfort, it limits the ability to extend the use of the product. in order to reduce the possibility of provider contamination from droplets entering this top opening, a bouffant surgical cap can be pulled forward and attached to the four pins of the headband holding the face guard in place. another option to mitigate this concern is to print a cover piece for the headband, which is currently under development [14] . however, for our purposes of rapidly producing enhanced ppe in the form of face shields, this design met the needs of our department. given the emergent circumstances and perceived time constraints, institutional infection control was notified, provided input, and was responsible for determining the sites for donning, doffing, and disinfection protocol. while the goal of the authors is to provide a detailed protocol and methodology that met the urgent needs of the unmc department of anesthesiology, modifications may be desired, or even necessary, depending on the availability of resources. to that end, we have included popular modifications and additional product resources. if a prusa brand printer is unavailable, or undesirable for other reasons, printer options with similar functionality are available. we recommend the creality cr-10s pro v2 (https://www.creality3dofficial.com/) or the creality ender 5 series that was used to produce face shields in-house for tamc personnel. for this protocol, we recommend using pla due to its characteristics and compatibility with this project. other types of filaments could be used; however, they would require significant modifications of this protocol and additional steps. a 10" piece of foam is optional and can be attached to the headband. for the purchase, foam window seal can be found at any departmental store. make sure you have a 1/2 wide by 1/4 thick. to ensure that the foam holds in place, glue the foam into the headband. however, we do not recommend its use since it cannot be sterilized, nor detached from the headband. hence, if using the foam, the face shield will have to be disposed after a single use, and we therefore elected to not utilize a layer of foam inside the headband. there are several materials that can be used for the head strap. we tried three materials: rubber bands, elastic strips with buttonholes, and tourniquets. rubber bands have the advantage of being readily available, low-cost, ability to be sterilized in liquid and disposable. however, they were very difficult to adjust and tended to slip, making the security of the face shield a concern. however, they are easy to acquire and could be used if the urgency of the situation merited it. the elastic strip with buttonholes was also low-cost and somewhat easy to acquire, requiring a trip to a fabric or craft store. the buttonholes made adjustment and security of the face shield sufficient. however, the fabric-type and porosity of the material would not allow for reliable sterilization and reuse of the face shields. the material of choice for our design was a tourniquet used clinically for the placement of ivs or phlebotomy. this material was readily available, lowcost, able to be sterilized and did not get stuck in hair as easily as rubber bands we settled on an 8.5x11" clear 10mil polyvinyl chloride (pvc) binding cover as it was readily available and only created a small amount of distortion to the wearer's vision. the width permitted the holes to be punched to fit the rc3 headband. the edges were trimmed to prevent the lower corners from contacting the wearer's chest if they flexed their neck. the binding covers are offered in fixed width, to be used with standard-sized paper. nonetheless, if there is a need for adjusting the dimensions and size of the clear shield, one can replace the binding cover with laminating foil or plexiglas. however, there are limitations to using such materials, such as the need for additional equipment, such as a die cutter for the plexiglas or a laminating machine for the laminating foil. however, pvc poses no other benefits over these materials if this equipment and expertise in use are already available. due to the cleaning solution, the clear face guard became slightly blurred with time. additional clear face guards were available for providers who wanted to replace it. however, the number of times needed for the clear face guard to lose its transparency varied. we performed the swab method to recover organisms from the face shield surfaces, this method is commonly used in transfer studies [15, 16] , although other methods exist such as direct elution which may be more efficient in organism recovery from porous surfaces [17, 18] . the swab method was selected because it is simple and less labor-intensive than the direct elution method. it is acknowledged that swabs may retain some portion of organisms during plating. the rapid manufacturing capacity of commercially available desktop fdm printers paired with open source designed and readily available materials allowed for the creation of sufficient face shields to provide protection until other, more durable shields could be procured. at the time of this writing, these face shields have been in use in the unmc anesthesiology department for 97 days, and at tamc for 93 days. unmc is currently awaiting a locally-sourced injection molding type face shield that has a cover over the opening in the top. 3d printing can allow for not only rapid prototyping and iterative changes but can allow the user to manufacturer and augment key components of ppe when providers and first responders are faced with supply shortages. center for disease control and prevention. coronavirus disease 2019 (covid-19) a novel coronavirus from patients with pneumonia in china supporting the health care workforce during the covid-19 global epidemic covid-19: protecting healthcare workers covid-19 faq's commentary: masks-for-all for covid-19 not based on sound data interim infection prevention and control recommendations for patients with suspected or confirmed coronavirus disease 2019 (covid-19) in healthcare settings f2019-ncov%2finfection-control%2fcontrol-recommendations.html behavioral considerations and impact on personal protective equipment (ppe) use: early lessons from the coronavirus (covid-19) outbreak covid-19: doctors still at "considerable risk" from lack of ppe, bma warns headaches associated with personal protective equipment -a cross-sectional study among frontline healthcare workers during covid-19 the efficacy of medical masks and respirators against respiratory infection in healthcare workers. influenza other respir viruses additive manufacturing (3d printing): a review of materials, methods, applications and challenges comparative surface-to-hand and fingertip-to-mouth transfer efficiency of gram-positive bacteria, gram-negative bacteria, and phage transfer efficiency of bacteria and viruses from porous and nonporous fomites to fingers under different relative humidity conditions transfer of bacteria from fabrics to hands and other fabrics: development and application of a quantitative method using staphylococcus aureus as a model assessment of surgical instrument bioburden after steam sterilization: a pilot study clear face protector portion of shield 10 key: cord-267860-mc0xa5om authors: lam, simon c.; lui, andrew k.f.; lee, linda y.k.; lee, joseph k.l.; wong, k.f.; lee, cathy n.y. title: evaluation of the user seal check on gross leakage detection of 3 different designs of n95 filtering facepiece respirators date: 2016-05-01 journal: am j infect control doi: 10.1016/j.ajic.2015.12.013 sha: doc_id: 267860 cord_uid: mc0xa5om background: the use of n95 respirators prevents spread of respiratory infectious agents, but leakage hampers its protection. manufacturers recommend a user seal check to identify on-site gross leakage. however, no empirical evidence is provided. therefore, this study aims to examine validity of a user seal check on gross leakage detection in commonly used types of n95 respirators. methods: a convenience sample of 638 nursing students was recruited. on the wearing of 3 different designs of n95 respirators, namely 3m-1860s, 3m-1862, and kimberly-clark 46827, the standardized user seal check procedure was carried out to identify gross leakage. repeated testing of leakage was followed by the use of a quantitative fit testing (qnft) device in performing normal breathing and deep breathing exercises. sensitivity, specificity, predictive values, and likelihood ratios were calculated accordingly. results: as indicated by qnft, prevalence of actual gross leakage was 31.0%-39.2% with the 3m respirators and 65.4%-65.8% with the kimberly-clark respirator. sensitivity and specificity of the user seal check for identifying actual gross leakage were approximately 27.7% and 75.5% for 3m-1860s, 22.1% and 80.5% for 3m-1862, and 26.9% and 80.2% for kimberly-clark 46827, respectively. likelihood ratios were close to 1 (range, 0.89-1.51) for all types of respirators. conclusions: the results did not support user seal checks in detecting any actual gross leakage in the donning of n95 respirators. however, such a check might alert health care workers that donning a tight-fitting respirator should be performed carefully. the unremitting worldwide outbreaks of different infectious respiratory diseases, such as severe acute respiratory syndrome, multidrug-resistant tuberculosis, avian influenza a (h5n1, h5n2, h7n2, and h7n3), and human swine influenza (h1n1), 1-6 have caused increased awareness of occupational protection among health care workers. therefore, use of n95 filtering facepiece respirators (also known as n95 respirators) to prevent spread of droplets transmitted and potential airborne infectious diseases is recommended internationally through announcements by the world health organization (who) and u.s. centers for disease control and prevention (cdc). 7, 8 regardless of the shapes or brands of such respirators, they are generally a tight-fitting half facepiece type, and their reliability is simply dependent on fit to the wearer. 9 according to a laboratory performance evaluation conducted by the cdc, the average penetration by ambient aerosol was found to be 33% in ill-fitting respirators compared with 4% in well-fitting respirators. 9 it is believed that the gap existing between the respirator and the wearer's face contributes to such penetration, which is often regarded as leakage. to achieve creditable occupational protection, most well-known authorities, such as the national institute for occupational safety and health, cdc, and who, made fit testing compulsory for wearers prior to use of an n95 respirator. 7, 8 in hong kong, fit testing should be a mandatory measure for frontline health care staff working in public and private hospitals. quantitative fit testing (qnft) is a recognized method to determine whether a tight-fitting respirator fits a wearer. this method adopts an electronic device to measure the ratio of particular air particles inside and outside the breathing zone (when donned with a respirator), and the ratio reflects the degree of leakage. 10 to make it simple, qnft is "an assessment of the adequacy of respirator fit by numerically measuring the amount of leakage into the respirator." 10 to assess any possible leakage, most of the preset fit testing systems require the wearer with a donned n95 respirator to perform a series of exercises, including a static portion without body movement (ie, normal and deep breathing) and a dynamic portion with both normal breathing and designated movements (ie, side-to-side head movement, up and down head movement, talking or reading a standard set of passages, grimacing, bending over). these exercises simulate the common working activities in the clinical environment; hence, the results of qnft can conservatively reflect any possible leakage. the characteristics of objective measurement and an automatic process increase the significance of qnft, which now serves as the gold standard in worldwide guidelines and research literature. [10] [11] [12] [13] [14] [15] [16] [17] although qnft warrants reliability of n95 respirator usage, any significant change in facial morphology, body weight, or donning method may contribute to on-site leakage. 10, 18, 19 therefore, even if a given respirator is considered fit by the recognized fit testing, a user seal check is still suggested in order to check the appropriateness of every donning. 10, [20] [21] [22] a user seal check is a self-examination procedure for wearers of n95 respirators to identify on-site gross leakage through repeated visual checks on obvious gaps and positive and negative pressure checks on the seal. 10, 15, [20] [21] [22] n95 respirator manufacturers and some authorities recommend that this practice should be routinely carried out by frontline health care workers. 10, 20, 21 previous experimental studies on u.s. subjects suggested that the user seal check improved the donning of n95 respirators. 23, 24 although the scale of these studies was not large enough (n = 11 and n = 64), 23,24 the rigor of the experimental design and the use of repeated measurements increased the credibility of the results. some guidelines suggest that no further fit testing is needed for a given respirator if subjective leakage is detected by a user seal check. this check may substitute for fit testing if fit testing is not available because of logistic difficulties or failure of the fit testing system. several recent studies, nevertheless, have consistently rejected this suggestion of substitution. 12, 14, 15, 25 in hong kong, a retrospective study demonstrated that the user seal check failed in determining the fit of n95 respirators because its false-positive (19%-31%) and false-negative (24%-40%) rates were too high among 84 chinese nursing staff. 12 lam et al further supported the previously mentioned claim through 2 prospective studies on chinese nursing students (n = 204 and n = 349, respectively) by presenting the sensitivity (15%-23%), specificity (89%-90%), positive (46%-63%) and negative (60%-67%) predictive values, and kappa values (-0.031 to -0.047, p > .05) of the user seal check. 14, 15 in a canadian study, similar results and conclusions were also reported on research involving 784 health care workers (false positive rate: 25%-30%). 25 the congruent results indicate that the user seal check cannot replace the fit testing. it is believed that the user seal check, which does not involve any dynamic body movement, is unlikely to mirror the fit testing results because the latter assessment is performed when the wearer performs 8 sequential exercises involving a series of head and body movement. however, the user seal check may still be able to identify onsite gross leakage and give some information on the gross leakage on normal breathing or deep breathing without head and body movement. given its immense implication on occupational protection, its validity has not yet been rigorously studied. therefore, the research question was as follows: can the result of the user seal check reflect the actual gross leakage under the conditions of normal and deep breathing? this study, hence, aimed to examine the sensitivity, specificity, predictive values, and likelihood ratios of the user seal check on actual gross leakage detection during normal breath-ing or deep breathing without head and body movement in 3 common respirator models of different designs. this study used a descriptive, prospective, and cross-sectional research design. from september 2010-december 2011, a convenience sample of 647 chinese students who studied in different nursing programs (ie, year 1 of bachelor's or higher diploma program) in a local university was invited to participate by internal e-mails and several announcements. data collection consisted of 3 phases (ie, registration, training session, fit testing session) (fig 1) . the demographic data of participants (sex, body height, and weight), the results of the user seal check, and the results of actual gross leakage detection through the fit testing device were recorded in a data sheet. during the registration, all participants were required to sign the consent form and prepare themselves in the same manner and appearance of clinical practicum (eg, pinning up long hair, shaving). in the training session, a 30-minute training, including video, demonstration, and practice on standardized n95 respirator donning technique and the user seal check method, was introduced by trained registered nurses. through redemonstration, the donning techniques and user seal check method of each participant were assessed by these nurses prior to moving on to the next session. apart from the time used in registration and the training session (various times among the participants), it took another 15 minutes to complete the remaining process of data collection, namely the user seal check and qnft on the exercises of normal and deep breathing for the given 3 types of n95 respirators, where the sequence of testing remained unchanged for all participants. to control the environmental factors, such as the concentration of suspended particles and dusts, which may affect the result of fit testing, all of the data were collected in an assigned air-conditioned room with an area of 10 m 2 , temperature at approximately 23°c, and humidity at approximately 75%. 15 to perform a user seal check, the wearer subjectively assessed and adjusted the position and tightness of a given n95 respirator through a visual check and positive and negative pressure checks. details on the steps and methods for the user seal check can be found in previous studies. 10, 15, 22 a positive result is indicative of subjective gross leakage. 14,15 the portacount pro+ respirator fit tester 8038 (tsi, st paul, mn) was adopted to measure the actual gross leakage. the details, including technologic information and protocol setting of this system, were introduced elsewhere. 10,15,18 currently, this system is widely adopted in public and private hospitals in hong kong and is used as a local quality control standard by respirator manufacturers. figure 2 shows the fit tester system, tubing connection, and respirator. all of the participants were only required to perform the static portion out of the 8 specified exercises (ie, normal breathing, deep breathing). in this portion, the participants should remain still in a normal standing position and breathe as usual for 60 seconds before taking long deep breaths as if working hard for another 60 seconds. the research nurses monitored and assessed chest movement by visual inspection to estimate adequacy of the depth (fig 2) . these 2 exercises gave particular individual fit factors (ffs; range, 0-200). each ff is the ratio of a challenge agent (ambient particles) concentration outside the respirator to the concentration of a challenge agent that leaks into the inside of the respirator. a ff <100 under the normal breathing and deep breathing exercises is defined as actual gross leakage. 10, 16 the higher the ff, the lesser amount of leakage. the portacount pro+ respirator fit tester 8038 went through a daily check procedure to warrant the sufficiency of ambient particles and performance of the system. 15 the cup-shaped 3m-1860s (3m, minneapolis, mn) (3m-a), 3-panel designed 3m-1862 (3m) (3m-b), and pouch-type kimberly-clark 46827 (kimberly-clark, neenah, wi) (kc-c) n95 respirators were selected. the selection was based on 3 reasons. first, these 3 models are typically and widely used in local clinical settings. second, previous studies demonstrated that the prevalence of the fittesting failure rate was approximately 40% for the 3m models. 11, 12, [14] [15] [16] it is estimated that the prevalence of actual gross leakage would be lower than that. according to our previous experience on qnft, the obtained ffs of normal and deep breathing were generally higher than that of the other exercises. extreme prevalence rates, such as <20% or >80%, greatly deteriorated the accuracy of both positive and negative predictive values. 26, 27 the prevalence rate of actual gross leakage among the 3 different designs of respirators should be within the optimal range for calculation of the predictive values. finally, it is unrealistic and unnecessary to include all types of n95 respirators for fit testing. in general, most of them were designed under these 3 categories. this study used a representative respirator from each category; hence, the results could provide a better evaluation on the validity of the user seal check. ethical approval was sought from the president's advisory committee on research and development, the open university of hong kong. an invitation letter was prepared. information about the purposes of the study, right to confidentiality, right to withdrawal, and duration of fit testing and a consent statement were provided. participants' written consent was obtained prior to data collection. descriptive statistics were used to present the participants' demographic variables and the results of the user seal check (ie, positive, negative) and actual gross leakage (ie, pass, fail). independent sample t tests were undertaken to test for the difference between participants in the 2 groups (positive and negative user seal checks) with regard to their results of ff. the significance level was set at p < .05. the results of the user seal check compared with the gold standard qnft on actual gross leakage through cross tabulation were used to compute the following diagnostic parameters: sensitivity, specificity, positive and negative predictive values, and likelihood ratios (refer to the "note" in table 4 for the respective formula). the sensitivity (ability of the user seal check to correctly identify a case with gross leakage) and specificity (ability of the user seal check to correctly identify a case without gross leakage) were calculated from the measurements. according to the evaluation of the performance characteristics of diagnostic tests in the medical literature, a combination of high sensitivity and specificity (>80%) [28] [29] [30] is equally important and is an indication of the characteristics of the user seal check itself (ie, test's ability). 31 because the user seal check is applied in clinical practice, additional performance evaluations, positive and negative predictive values, 32 are necessary to help interpret the results. a value ≥80% is considered to be satisfactory for both predictive values. 27 another method for describing the screening accuracy of the user seal check is the likelihood ratios. the ratios have an advantage over the aforementioned sensitivity, specificity, and predictive values because they are independent of the prevalence of actual gross leakage and hence can be applied across settings and populations. 31 according to the recommendation of using probabilistic reasoning, 31, 32 the user seal check is moderately good at ruling in leakage if the positive likelihood ratio is >2. conversely, such a check is moderately good at ruling out leakage when the negative likelihood ratio is <0.5. values close to 1.0 represent that the user seal check is useless in predicting the presence or absence of actual gross leakage. a total of 638 nursing students participated in the study. for those who did not participate or were excluded, the reasons included 6 who were physically unfit (eg, asthmatic attack, influenza), 2 who were absent (eg, withdrew from the program), and 1 who had unshaven bushy facial hair. the participants ranged from 18-30 years of age, and 25.5% of them were men (n = 163). their mean height was 163.1 ± 7.69 cm, and their weight was 56.2 ± 11.14 kg. as far as the ffs between a group of positive and negative user seal checks were concerned, generally the participants with negative user seal checks obtained an observable higher score in the 3 types of respirators compared with those with a positive check. however, only significant differences were found regarding the use of the kc-c respirator (t = 2.01-2.75, p = .006-.045) ( table 1) . the results of the user seal check compared with that of actual gross leakage performed by qnft are presented in tables 2 and 3 . among the participants, 25.7% (n = 164), 20.4% (n = 130), and 24.5% (n = 156) reported positive user seal checks regarding the 3m-a, 3m-b, and kc-c respirators, respectively. however, the prevalence of actual gross leakage identified by qnft in normal breathing was 34.3%-39.2% in both of the 3m respirator models and 65.8% in the kc-c model. in deep breathing, the prevalence was similar, 31.0%-35.0% in both of the 3m respirator models and 65.4% in the kc-c model. testing on the 3 different respirators in the 2 breathing conditions, the sensitivity and specificity of the user seal check for identifying a case with actual gross leakage ranged from 21.5%-28.0% and 75.2%-81.7%, respectively (table 4 ). extreme prevalence rates caused deviation of positive predictive values and negative predictive values. 27 according to the current results on prevalence rates of actual gross leakage (ie, between 31.0% and 65.8%), further evaluation on the characteristics of the test's performance of positive and negative predictive values was regarded as appropriate. regarding the test of the 3m respirators, the positive predictive values of a positive user seal check for estimating the probability of actual gross leakage ranged from 34.6%-42.7%, whereas the negative predictive values ranged from 62.0%-69.9%. in contrast, the test of the kc-c respirator showed different patterns, which were of relatively high positive predictive values (69.9%-74.4%) and low negative predictive values (36.1%-36.9%). finally, both the positive and negative likelihood ratios indicating the post-test probability of the user seal check were close to 1.0 (positive likelihood ratio range, 1.08-1.51; negative likelihood ratio range, 0.89-0.98). table 4 presents the detailed results. concerning the 3m respirators, the observed differences of the ffs between a group of participants with positive and negative user seal checks were minimal and these differences were not statistically significant at all (123.8-134.5 vs 127.2-141.9, respectively). although a significant difference was found for use of the kc-c respirator, the mean score of the ff of a group of negative user seal checks (no subjective gross leakage) was still <100 (a detection of actual gross leakage), which implies that kc-c respirator is difficult to fit chinese participants. concerning donning with 3m respirators, the prevalence of actual gross leakage in this study (31%-39%) was slightly lower than that of the failure rate of fit testing in previous studies (35%-43%). 12, 14, 15 this was not surprising because the fit testing examines the degree of leakage during a series of exercises, whereas the actual gross leakage is computed only based on the measured ff on the static portion. however, the actual gross leakage that was found in the kc-c respirators was still frequent (up to 65%). it may imply that a higher failure rate on fit testing of this model was expected among the chinese population. this warrants future empirical testing. the positive user seal checks ranged from 20%-25% in the current study, which is comparable with that of previous studies (10%-29%). 12, 14, 15 in some occasions, participants who felt the gross leakage of a given respirator (assessed by the user seal check) passed the fit testing in normal and deep breathing (ie, false-positive rate: 19.3%-24.8%). in contrast, more frequently, participants subjectively expressed the good fit of a given respirator, but the actual gross leakage was still detected by qnft in normal or deep breathing mode (ie, falsenegative rate: 72.0%-78.5%). similar observations were consistently reported in the literature, 12, 15 which reinforced that the leakage between the face and respirator is unlikely identified by human sense. the literature indicated the sensitivity and specificity of the user seal check in determining the fit of n95 respirators were 15%-23% and 89%-90%, respectively. 14, 15 such results suggested that the user seal check cannot replace the fit testing because the fit testing simulated a series of head and body movement on leakage detection. the current study hypothesizes that the user seal check may contribute to the detection of gross leakage in normal and deep breathing, which is important information during on-site donning. 25, 26 however, based on the unacceptable sensitivity (21.5%-28.0%) and specificity (75.2%-81.7%) in the current results, the hypothesis that the user seal check is able to detect actual gross leakage in normal and deep breathing is also rejected. interestingly, the sensitivity and specificity of the user seal check in determining the fit of n95 respirators and in detecting gross leakage are fairly comparable. such a phenomenon may imply that leakage in normal and deep breathing shall predict the result of fit testing. however, further empirical testing is warranted to work out this possibility. to illustrate the clinical implication of the current results of predictive values and likelihood ratios, by using an example of donning the 3m-a respirator, an interpretative summary of the validity and test performance of the user seal check for identifying actual gross leakage is presented as follows. the prevalence of the actual gross leakage was approximately 37% (39.2-35.0%, as indicated in table 4 ) when donning the given respirator, which was interpreted as pretest probability. 32, 33 before conducting any kind of testing, a randomly selected nurse wearing the 3m-a respirator would have a 37% chance of having actual gross leakage. predictive values vary according to the prevalence of the actual gross leakage. high prevalence tends to have higher positive predictive value, whereas low prevalence tends to have higher negative predictive value. [26] [27] [28] the current prevalence of actual gross leakage was approximately 37% as mentioned, which was satisfactory in further calculating post-test probability. this nurse then performs a routine user seal check to ensure the absence of subjective gross leakage. likelihood ratios help to calculate post-test probability of actual gross leakage. the current results indicated that positive and negative likelihood ratios were 1.13 and 0.96, respectively. therefore, with these ratios, the chance of the nurse with a positive user seal check having actual gross leakage is 41.8% (37% × 1.13), whereas a negative user seal check reduces the chance of the nurse having such leakage from 37% to 35.5% (37% × 0.96). figure 3 illustrates such probabilities through the nomogram. based on this example, the practice of the user seal check provides limited information in predicting the actual gross leakage when donning the given respirator. several limitations deserve discussing. one is that only 2 brands of respirators (ie, 3m and kimberly-clark) were used for gross leakage detection through qnft. although our aim was not to investigate the prevalence of gross leakage of all different models of n95 respirators, it was possible that different results might be obtained with different respirators. nevertheless, we believe that the results supported the unacceptably low sensitivity and positive predictive value and futile likelihood ratios of the user seal check in identifying gross leakage of respirators. apart from this, participants' characteristics might affect the passing rate of fit testing. first, most participants were novice users, except that some worked in clinical settings as health care workers. previous experience and knowledge of donning an n95 respirator were insufficient, which may influence the passing rate of qnft on gross leakage detection. this is different from a previous study, where viscusi et al recruited subjects who were required to pass a standard qnft. therefore, the current results may underestimate the passing rate of qnft. 24 second, asian participants' weight (reported here) and facial anthropometries (eg, face length, face width; not reported here) were significantly different from that of non-asian people, which hence affects the passing rate of qnft. such differences might reduce the generalizability of the results but increase the specificity of that to asian populations. concerning environmental factors, the average monthly humidity in hong kong (subtropical climate) ranged from 67%-86% in 2014 34 ; yearly humidity computed from 2000-2014 was 78.1%. most hospitals are only equipped with central air conditioning systems, and indoor humidity of wards may vary from 65%-75%. relatively high humidity might underestimate the positive result of the user seal check in the current study because participants rely on subjective comparison between inward and ambient air to detect the leakage. unlike well-controlled internal hospital settings in other regions, these environmental differences may limit the current results in that they are less relevant to other settings but are highly situation-specific results for many hospitals located in subtropical climate regions. further studies are recommended to replicate the works from myers et al 23 and viscusi et al, 24 which examined the effectiveness of the user seal check on improving n95 respirator donning among asian wearers. another study may investigate how the change of body weight and facial anthropometries of asian health care workers contributes to leakage of n95 respirators. it is difficult to cite any evidence on the value of the user seal check on determining the fit of n95 respirators or even detecting any actual gross leakage during normal and deep breathing. however, the practice of the user seal check might contribute to enhancing the donning procedure of a respirator. although the leakage is difficult to identify by subjective human sense, this check draws our attention to the issue that the tight-fitting respirator should be worn carefully. effectiveness of precautions against droplets and contact in prevention of nosocomial transmission of severe acute respiratory syndrome (sars) h5n1 outbreaks and enzootic influence influenza pandemics of the 20th century face mask use and control of respiratory virus transmission in households multidrugresistant tuberculosis outbreak among us-bound hmong refugees worldwide emergence of extensively drug-resistant tuberculosis epidemic and pandemic alert and response (epr): infection prevention and control of epidemic-and pandemic-prone acute respiratory disease in health care: who interim guidelines guidelines for preventing health-care-associated pneumonia, 2003: recommendations of cdc and the healthcare infection control practices advisory committee laboratory performance evaluation of n95 filtering facepiece respirators 1996 regulations (standards-29 cfr), occupational safety and health standards the fitness of n95 respirators among undergraduate chinese nursing students in hong kong predictive value of the user seal check in determining half-face respirator fit protecting healthcare staff from severe acute respirator syndrome: filtration capacity of multiple surgical masks respiratory protection by respirators: the predictive value of user-seal-check for the fit determination in healthcare settings sensitivity and specificity of the user-sealcheck in determining the fit of n95 respirators testing of the sensitivity and specificity of the user-seal-check procedure on "gross leakage" of n95 respirators racial differences in respirator fit testing: a pilot study of whether american fit panels are representative of chinese faces portacount pro 8030 respirator fit testers: operation and service manual respirator donning in post-hurricane new orleans 3m occupational health and environmental safety division qualitative fit testing instructions (kcpi-0356) use of personal protective equipment for respiratory protection effectiveness of fit check methods on half mask respirators evaluation of the benefit of the user seal check on n95 filtering facepiece respirator fit health care workers and respiratory protection: is the user seal check a surrogate for respirator fit-testing? understanding diagnostic tests 1: sensitivity, specificity and predictive values how to report statistics in medicine the sensitivity, specificity, and predictive value of traditional clinical evaluation of peripheral arterial disease: results from noninvasive testing in a defined population systematic reviews of evaluation of diagnostic and screening tests evaluation of sensitivity and specificity of rapid influenza diagnostic tests for novel swine-origin influenza a (h1n1) virus foundations of clinical research: applications to practice diagnosis in general practice: using probabilistic reasoning evidence-based medicine: how to practice and teach ebm the year's weather-2014 we thank all participants for their contribution to this study; jojo y.y. kwok, billy o.y. pang and rebecca c.m. tsang for supervision on data collection; ka-yan chan, suen-fuk fan, nga-yi lau, sinting tai, tsz-kwan yuen, wai-hung chung, and wing-on lui for assistance on data collection and data input; andy c.y. chong for provision of statistical support; and our division for support on specific equipment, consumables, and room usage. key: cord-275997-4ibeidyw authors: goldrick, barbara a. title: the practice of infection control and applied epidemiology: a historical perspective date: 2005-10-31 journal: am j infect control doi: 10.1016/j.ajic.2005.04.250 sha: doc_id: 275997 cord_uid: 4ibeidyw the united states health care system and patient populations have changed substantially over the past several decades. the practice of infection control also has evolved since the landmark study on the efficacy of nosocomial infection control project, and infection control professionals (icps) must continue to develop the knowledge and skills necessary to practice infection prevention and control. practice analyses of infection control conducted between 1982 and 2001 were analyzed to determine changes in practice. these data reflect a 145% increase in infection control activities over a 20-year period. however, resources for infection control and prevention have not kept pace with this increased activity. in addition, the current trend toward mandatory reporting of health care-associated infections (hais) among several states will add more tasks for icps with limited resources, at the risk of spending less time on prevention and control activities. in keeping with its philosophy of quality health care and responsible public reporting, the association of professionals in infection control and epidemiology, inc, continues to explore the issue of mandatory reporting of hais. the practice of infection control and applied epidemiology: a historical perspective barbara a. goldrick, rn, phd, mph, cic chatham, massachusetts the united states health care system and patient populations have changed substantially over the past several decades. the practice of infection control also has evolved since the landmark study on the efficacy of nosocomial infection control project, and infection control professionals (icps) must continue to develop the knowledge and skills necessary to practice infection prevention and control. practice analyses of infection control conducted between 1982 and 2001 were analyzed to determine changes in practice. these data reflect a 145% increase in infection control activities over a 20-year period. however, resources for infection control and prevention have not kept pace with this increased activity. in addition, the current trend toward mandatory reporting of health care-associated infections (hais) among several states will add more tasks for icps with limited resources, at the risk of spending less time on prevention and control activities. in keeping with its philosophy of quality health care and responsible public reporting, the association of professionals in infection control and epidemiology, inc, continues to explore the issue of mandatory reporting of hais. (am j infect control 2005;33:493-500.) the major infection control movement emerged in the united states in the 1970s. and by the mid-1970s, thousands of hospitals throughout the country had infection surveillance and control programs (iscps) in place. however, it was not until the landmark study on the efficacy of nosocomial infection control (senic), which was conducted by the centers for disease control (cdc) in the mid-1970s, that the link between iscps and the reduction of nosocomial infections (nis) in acute care facilities was established. 1 the senic demonstrated that effective iscps were associated with a 32% reduction in nis. 2 the senic project found that, prior to 1970, very few hospitals in the united states had an infection control professional (icp), but, by 1977, 80% of the hospitals had at least 1 icp. 3 in the early 1970s, the cdc recommended that hospitals have at least 1 full-time equivalent (fte) icp for every 250 beds 4 ; however, the senic found that only 28% of the icps surveyed worked full-time specifically on infection control activities, and the amount of time was related to hospital size, with an overall average of 24 hours per week. 3 the extensive 1976 revisions to the joint commission on accreditation of hospitals (jcah) guidelines for infection control, which formally recommended a position responsible for surveillance, added further impetus to include icp positions to hospital infection control programs. 5 until the senic, there were no published studies that assessed the dimensions of infection control practice; therefore, the senic project included a study of the role of the icp. nearly all (94%) of icps surveyed in 1976-1977 were registered nurses (rns), with two thirds of these having a diploma in nursing, one fourth a baccalaureate degree, and 8% an associate degree. the senic also identified 5 practice activities among icps: surveillance, policy development, training, epidemic investigations, and consulting 3 (table 1) . however, there were no certification standards for the icp at the time of the senic project. the association for practitioners in infection control, inc. (apic), a multidisciplinary organization, was established in 1972 to meet the education and practice needs of icps in the united states. the name was changed to the association for professionals in infection control and epidemiology, inc, in 1994 to recognize the organization's maturation and evolution into the broader context of health care delivery in the united states. 6 apic's sister organization, community and hospital infection control association-canada (chica-canada), was incorporated in 1976 for icps practicing in canada. 7 the apic developed 8 educational standards for infection control practice in 1980, which included epidemiology; microbiology; infectious diseases; sterilization, disinfection, and sanitation; patient care practices; education; management and communication; and employee health. 8 these standards were consolidated into the apic curriculum for infection control practice, which was published in 1983. 9 the first infection control practice analysis (pa) was conducted in 1982 at the request of the certification board of infection control (cbic), which was established in 1981. 10 the first pa survey collected demographic data and data from a task inventory rating scale, which consisted of 99 task statements, categorized according to the 8 educational standards of apic. 8 a randomized stratified sample of 600 icps who would receive the pa questionnaire was deliberately skewed toward larger hospitals (.100 beds) because the pa committee felt that these hospitals would most likely employ icps who performed the full range of infection control activities. based on inclusion/exclusion criteria, a total of 317 icp respondents' data were used for analysis to determine key tasks for infection control practice. 11 most (88%) of respondents in the 1982 pa survey were rns who worked in community hospitals (78%) with .200 beds (73%). all but 4% of the respondents' hospitals were accredited by the jcah. 12 although the majority of the respondents were full-time employees, 17% spent less than 20 hours/week in infection control, and many held multiple positions within the hospital; however, 54% of the icps surveyed indicated that infection control was their primary responsibility. the majority (72%) of respondents had been in infection control practice between 2 and 10 years, and nearly all (96%) had attended educational programs in infection control. sixty tasks (activities) related to the 8 areas/dimensions of infection control practice were identified as relevant in the 1982 pa 11 (table 1 ). the 1982 pa was the basis for the first infection control certification examination, which was offered in the united states in 1983. 11 it also defined and described the scope of infection control practice for the first time and established a baseline for measuring progress and changes in practice. 11 recertification for icps is required every 5 years; therefore, the cbic repeats the pa every 5 years. 10 by the 1980s, infection control practice had expanded beyond the acute care setting. infection control practice also had changed considerably. new infectious diseases such as acquired immunodeficiency syndrome had emerged, prospective payment systems for hospitals were in place, and the joint commission on accreditation of health care organizations (jcaho; formerly jcah) instituted outcome measures as part of the accreditation process. these changes required new or enhanced skills for the icp. therefore, in 1987, 5 years after the first infection control pa, a study was conducted to update and revalidate the original (1982) pa to ensure that the content of the certification examination was a valid representation of infection control practice. a modified delphi technique was used between 2 panels of icps and further validated by a third panel of subject matter experts for a total of 29 icps. there was a high level of agreement between respondents on the 1982 pa, the 1987 icps, and the expert panel, providing content validity for the certification examination based on current infection control practice. eight new tasks (activities) were identified for a total of 67 tasks in 8 areas (dimensions) of infection control practice (table 1) . these additional tasks ''reflect[ed] an expanding role of the icp as a planner and manager.'' 13 the cbic conducted its second pa survey among icps in 1992, which included a random sample of canadian icps for the first time. the original 1982 pa list was used with modifications to reflect current infection control practice and terminology. a total of 577 responses were available for analysis. the majority (87%) of respondents were rns; 9% held an associate degree; 44% held a baccalaureate degree; and 24% held an advanced degree. 14 the majority of respondents had 9 years or more in infection control practice (56%), worked in hospitals with greater than 200 beds (64%) less than 40 hours a week (52%), and were certified in infection control (72%). ninety-five tasks identified in the 1992 pa were organized into 5 major practice dimensions describing the responsibilities of icps in the united states and canada: infectious process, surveillance/epidemiologic investigation, transmission of infection, management and communication, and education 14 (table 1) ; however, new tasks were added, and outdated tasks were eliminated. 14 each pa builds on those conducted previously and is an important component of ensuring content validity that reflects current infection control practice. this process of content validation involves systematic collection of information that describes behaviors and activities (tasks) performed by occupants of the practice in question. 15 because of the numerous changes in health care delivery, which affected the scope and practice of infection control since the 1992 pa, a more contemporary analysis of infection control practice was needed in the 1996 pa survey conducted by the cbic. the application of decision rules ensured that the resulting certification examination accurately reflected infection control practice in the united states and canada, regardless of the region or size of facility. a representative sample across all health care settings was selected from the apic and the chica-canada icps to receive the 1996 pa questionnaire. 16 a return of 1530 responses significantly exceeded the n 5 1067 required by power analysis. as in past pa surveys, the majority (85%) of respondents in the 1996 survey were rns. thirteen percent of respondents held an associate degree; 41% held a baccalaureate degree; and 22% had an advanced degree. 16 the majority of respondents in the 1996 pa survey worked in acute care settings (65%), worked in facilities with greater than 100 beds (68%), and worked less than 40 hours per week in infection control (62%). nineteen percent of the respondents worked in long-term care (14%), mental health facilities (3%), and rehabilitation centers (2%). thirty-five percent of the respondents had 10 or more years of experience in infection control practice, but less than half (48%) were certified in infection control. 16 the completed inventory on the 1996 pa resulted in127 tasks organized into 5 major practice areas, 16 as listed in table 1 . the apic/chica-canada infection control and epidemiology: professional and practice standards were published in 1999. 17 the document has the following 2 sections: (1) professional standards that the icp is expected to meet or exceed and (2) practice standards that the icp is capable of meeting, regardless of applicability to the specific practice setting. these professional and practice standards were synthesized into the most current pa survey, which was conducted by the cbic in 2001, to ensure that the resulting content outline was consistent with current standards of infection control practice. the primary source for the 2001 pa survey questionnaire was the 1997 infection control professional task list. 16 the target population for the survey consisted of icps in the united states and canada who met the eligibility requirements for taking the certification examination. a final sample of 1306 responses were available for analysis in the 2001 pa survey, which significantly exceeded the n 5 1067 required by power analysis. therefore, results from this sample could be generalized to icps in the united states and canada. in the continuing process of serving the international infection control community, the survey instrument also was distributed to a selected sample of international icps. 18 table 1 outlines the 6 major areas of infection control practice identified in the 2001 pa. two changes in the major areas of practice were made. these included a category that incorporates both education and research. research had not been considered in previous pas; however, because there were only 5 tasks associated with the ''research'' category, it was combined with the ''education'' category, and the category was renamed ''education and research.'' several new tasks associated with employee health also were identified. as a result, all aspects of employee health were separated into a new category: ''infection control aspects of employee health,'' which had previously been included in the category that addressed preventing and controlling the transmission of infectious agents. 18 table 1 indicates that 147 tasks related to the 6 areas of infection control practice were identified in the 2001 pa. the majority of respondents in the 2001 pa survey was rns (80%), held a baccalaureate degree or advanced degree (73%), and was certified in infection control (84%). more than half (55%) of the respondents had been in infection control practice more than 10 years. most of the respondents (56%) worked in an acute care hospital with $200 beds (51%) with #1 full-time equivalent icp (59%), and nearly half (49%) worked 40 or more hours a week. eight percent of the respondents worked in long-term care (compared with 14% in 1996), 4% worked in public health, and 2% worked in mental health facilities. 18 the 2001 pa reflected changes in the practice of infection prevention/control and applied epidemiology at that time and identified the responsibilities of the icp both in the united states and in canada. 18 however, several new infection control activities have been identified since 2001. to remain current, the cbic will conduct its next pa in 2006, which will include tasks related to changes in infection control practice since 2001. table 1 illustrates that the practice of infection control evolved significantly between 1976 and 2001. figure 1 shows the increase in infection control tasks from 60 to 147 between 1982 and 2001, a 145% increase over a 20-year period, with little or no additional resources allotted to infection control programs during that time. although the 2001 pa survey 18 was undertaken early in 2001, long before the september 11, 2001 , attacks on the united states and the department of homeland security was formed, the cdc developed a plan to upgrade the nation's public health infrastructure to respond to acts of biological terrorism. 19 in 1999, the apic and the cdc developed a bioterrorism readiness plan ''. to serve as a tool for [icps] and health care epidemiologists to guide the development of practical and realistic response plans for their institutions in preparation for a real or suspected bioterrorism attack.'' 20 as a result, many icps across the united states developed policies and procedures based on the apic and the cdc recommendations to prepare their health care facilities to deal with bioterrorism, and, although bioterrorism was not a separate infection control practice category listed in the 2001 pa, 18 the tasks related to attacks of biologic warfare are another layer in the practice of infection control, which deals with the prevention and control of the transmission of infectious agents (table 1 ). since the september 11 attacks, there has been a substantial increase in icps involvement in emergency preparedness and management for bioterrorist attacks and emerging infections. for example, the recent emergence of severe acute respiratory syndrome (sars) and the threat of a new influenza pandemic are further examples of the need for due diligence in infection control. the main lesson learned from the sars outbreak was that it was contained through the conscientious application of enhanced infection control measures at the national and local levels. these same measures will defeat sars should it reemerge. control of an emerging infection requires swift action by health care providers and an adequate public health infrastructure. 21 as change in the health care system continues, infection control practice also must evolve. icps are instrumental in ensuring that their health care facilities comply with new regulations and guidelines, which include education of health care workers on proper hand hygiene, prevention of needlestick injuries, isolation techniques, and appropriate use of personal protective equipment, and are prepared for emerging and reemerging infectious diseases. in addition, changes in the us health care infrastructure occurred during the past 20 years when many hospitals merged or became part of multihospital health systems that included health care facilities across the continum of care. these changes in the organization and delivery of health care services prompted an expansion of the role of many icps to include not only the responsibility for infection control programs in acute care and/or long-term care facilities but the added responsibility for nonacute health services such as freestanding surgery centers, medical and dental clinics, rehabilitation units, child and adult day care centers, and home care. however, icps report that resources for the infection control staff have remained static despite the need to respond to emerging infections and implementation of new regulations and guidelines. emergence of multidrug-resistant microorganisms in all health care facilities also has necessitated increased icp activity. 22 o'boyle et al used a delphi method to study infection control tasks in addition to those found in the 1996 pa, along with additional responsibilities. 22 a panel of experts (n 5 32) from 20 states, who represented icps in acute care, long-term care, and community settings, identified 14 new tasks added to the 127 listed in the 1996 pa. the delphi panel also estimated the percentage of time used in the major infection control practice domains. 22 the activity with the greatest average estimated time was surveillance (27%), followed by education (16%), prevention (14%), and communication (14%). the activity with the least average estimated time was control measures (8%). lack of adequate resources was seen as influencing icps' ability to perform tasks across all infection control functions. 22 the panelists in the study determined that a ratio of 0.8 to 1.0 icp for every 100 occupied acute care beds was adequate infection control staffing. 22 despite the additional responsibilities involved in the practice of infection control, the ratio of 1 icp for every 250 acute care beds has continued in many health care facilities in the united states since the 1976 senic project. 2 however, the ratio of icps per 250 beds was a recommendation that was not evidence based. two recent reports recognized that the complexity of the current practices of icps has changed considerably since the senic and that the old ratio of 1 icp per 250 beds is no longer adequate. the authors also recommend that infection control programs be based on the scope of the infection control program rather than bed size. 23, 24 in the past year alone, 5 new guidelines for infection control practice were published. icps must be aware of these guidelines and implement those recommendations that are strongly evidence based. 25 the cdc recently released draft documents of revised isolation procedures and tuberculosis prevention guidelines. when the final documents are published, icps must implement the new recommendations. in addition, revised jcaho infection control standards, which went into effect in january 2005, include an emergency management plan (standard ic.6.10) that requires health care facilities to respond to epidemics and infections that may require expansion of patient care over extended periods of time. 26 the first report, which addressed the ratio of icps per number of beds since the senic project, was published in the canadian journal of infection control in the summer of 2001. 27 a canadian infection control alliance, consisting of infection control experts, was asked to reach consensus on the key components and resources needed to support effective infection prevention and control programs across the health care continuum: acute care settings, long-term care facilities, and community and home care settings. the alliance recommended 3 full-time equivalent icps for every 500 beds in acute care settings and 1 full-time equivalent icp for every 150 to 250 beds in long-term care facilities. the projected needs for icps in each of these settings was determined based on the expertise represented by members of the alliance. 27 22 and the canadian infection control alliance study 27 were conducted before the september 11 attacks on the united states and therefore do not reflect current infection control practice, which now includes emerging infections and bioterrorism preparedness. one state, new jersey, recently recognized the importance of infection control programs and published revised hospital licensure regulations that mandate an icp ratio of 1 full-time icp per 200 adjusted-occupied beds as a minimum standard. the adjusted-occupied bed calculation takes into account patient days, outpatient factors, and case mix. also mandated was certification by the certification board in infection control and epidemiology for all icps within 5 years of beginning infection control practice. 30 the 1999 landmark institute of medicine (iom) report on medical errors identified nosocomial infection surveillance as a model for voluntary patient safety reporting systems. 31 the national nosocomial infection surveillance (nnis) system, created by the cdc in 1970 to establish a national nosocomial infections database, is the nation's largest and oldest performance measurement system devoted to hospital-acquired infections. 32 the nnis system started with 62 hospitals in 1970, and, by 2000, approximately 315 hospitals were participating in the nnis system. participation in the nnis system is voluntary and involves only acute care facilities in the united states. surveillance data are collected uniformly by trained icps using standardized protocols that target inpatients at high risk of infection and are reported routinely to the cdc at which they are aggregated into a national database. participating hospitals are assured by law that the cdc will not provide any information that would identify any individual or institution and that the data received will be held in strict confidence. 32 icps in the nnis system collect data for selected ''surveillance components'': adult and pediatric intensive care units, high-risk nursery, and surgical patients, using standard cdc definitions that include both clinical and laboratory criteria. nnis data provide benchmarks to guide hospitals within and outside the nnis system to improve efforts aimed at reducing infection rates. nnis reports are published in the biomedical literature on a regular basis, with the latest providing data from january 1992 through june 2004. 33 the infrastructure of the nnis system offers a national resource on which to build improved voluntary patient safety monitoring efforts, as outlined in the 1999 iom report. 34 other than the nnis system, there currently is no national standardized method for collecting hospital infection data. in addition, because each hospital monitors those infections and procedures that are most risky for their specific patient populations, all hospitals do not monitor the same infections. nonetheless, by early 2005, 5 states-pennsylvania, missouri, illinois, virginia, and florida-had new regulations, which mandate that icps report hais to state agencies; however, each state's requirements differ. for example, the missouri regulations call for the ''methodologies and systems for data collection established by the federal centers for disease control and prevention national nosocomial infection surveillance system, or its successor .'' 35 the florida bill, on the other hand, would allow patients to request and obtain information about hospital infection rates. 36 mandatory reporting of hais is currently pending in at least 30 other states. 6 legislation for mandatory reporting of hais in california was vetoed by governor schwarzenegger, making the following case: 37 ''. infection control programs have considerable merit and are currently in effect. the department of health services and the joint commission on accreditation of health care organizations scrutinize hospital infection control programs and the national quality initiative is expected to more than double the number of quality indicators tracked by may 2005. this calls into question the need of a new program to address this issue .. the absence of data auditing and review by impartial clinical experts may call into question the quality and ultimate validity of the data on hospital-acquired infections ..'' the healthcare infection control practices advisory committee (hicpac) (formerly the hospital infection control practices advisory committee), which is authorized under the public health service act, advises the secretary, department of health and human services (dhhs) and the cdc regarding the practice of infection control and strategies for surveillance, prevention, and control of hais, antimicrobial resistance, and related events in settings in which health care is provided. the committee also advises the cdc on periodic updating of existing guidelines, development of new guidelines, and other policy statements regarding the prevention of hais. 38 in response to the recent states' legislation regarding mandatory public reporting of hais, hicpac released a document, guidance on public reporting of healthcare-associated infections, which includes recommendations for use by policy makers and organizations that are tasked to design and implement public reporting systems for hais. however, based on an extensive review of the scientific literature, hicpac found no conclusive evidence for or against public reporting of hais as a method to prevent or control their occurrence in health care settings. 39 the apic supports the right of consumers and purchasers of health care to expect quality health care and responsible public reporting of performance indicators. 6 in its 1998 position paper entitled ''release of nosocomial infection data,'' 40 the apic outlined specific guidelines for interhospital comparison of hai surveillance data. these included (1) trained icps who use standardized protocols for data collection, (2) maintenance of a continued level of surveillance over time, (3) consistent use of valid case definitions for identifying infections, (4) appropriate use of denominator data and time periods for rate-based data, and (4) risk stratification to control for different levels of illness among patients. 40 in keeping with its philosophy, mandatory reporting of hais has become a high priority issue for the association. on march 14, 2005 , the apic released its ''position on mandatory public reporting of healthcare-associated infections.'' 6 the apic continues to explore this issue with other stakeholders and to identify and develop informational resources to assist its members at the local level. 6 the united states health care system and patient populations have changed substantially over the past several decades. the practice of infection control also has evolved, and icps must continue to develop the knowledge and skills necessary to practice infection prevention and control as changes in health care, standards, guidelines, and regulations evolve. practice analyses of infection control conducted between 1982 and 2001 reflect an increase in infection control activities from 60 to 147 tasks in 6 areas of infection control practice, a 145% increase over a 20-year period. however, resources have not kept pace with the increase in infection control activities. in addition, the recent trend toward public reporting of hais will add more tasks for icps with limited resources, at the risk of spending less time on prevention and control activities. in keeping with its philosophy of quality health care and responsible public reporting, the apic continues to explore this issue. the emergence of infection surveillance and control programs in us hospitals: an assessment, 1976 the efficacy of infection surveillance and control programs in preventing nosocomial infections in us hospitals the infection control nurse in us hospitals, 1976-1977: characteristics of the position and its occupant a hospital program for control of nosocomial infections joint commission on accreditation of hospitals (jcah) association for professionals in infection control and epidemiology (apic) community and hospital infection control association (chica)-canada educational standards of the association for practitioners in infection control the apic curriculum for infection control practice. volumes i and ii certification board of infection control and epidemiology (cbic) part ii: tasks, knowledge, and abilities for practice a task analysis of infection control practitioners, 1982. part i: methodology and demography validating the certification process for infection control practice job analysis 1992: infection control practitioner practice analysis: building the foundation for validity job analysis 1996: infection control practitioner apic/chica-canada infection control and epidemiology: professional and practice standards practice analysis for infection control and epidemiology in the new millennium biological and chemical terrorism: strategic plan for preparedness and response bioterrorism readiness plan: a template for healthcare facilities public health grand rounds staffing requirements for infection control programs in us health care facilities: delphi project requirements for infrastructure and essential activities of infection control and epidemiology in out-of-hospital settings: a consensus panel report requirements for infrastructure and essential activities of infection control and epidemiology in hospitals: a consensus panel report. society for healthcare epidemiology of america the state of the science of health care epidemiology, infection control, and patient safety critical access hospitals surveillance, prevention and control of infection development of a resource model for infection prevention and control programs (ipcps) in acute, long term, and home care settings: conference proceedings of the infection prevention and control alliance development of a resource model for infection prevention and control programs (ipcps) in acute, long term, and home care settings: conference proceedings of the infection prevention and control alliance canadian report: icp needs across the health care continuum institute of medicine (iom) national nosocomial infections surveillance (nnis) system report, data summary from characteristics of hospitals and infection control professionals participating in the national nosocomial infections surveillance system section 11 consumer union healthcare infection control practice advisory committee (hicpac) healthcare infection control practice advisory committee (hicpac) association for professionals in infection control and epidemiology (apic) the next report from the cdc containing comparative healthcare-associated infection rates, which will include data from the national nosocomial infections surveillance (nnis) system and the first full year of data from the new national healthcare safety network (nhsn), will be published in june 2006. although nnis hospitals began collecting data under the new nhsn protocols beginning in january 2005, they have not been able to report these data to cdc yet, because of unforeseen complexities encountered in launching the web-based reporting tool. until the new report is available, the nnis report issued in october 2004 (published in december 2004) may be used for comparison purposes. key: cord-279640-n391v32y authors: atreja, ashish; gordon, steven m.; pollock, daniel a.; olmsted, russell n.; brennan, patrick j. title: opportunities and challenges in utilizing electronic health records for infection surveillance, prevention, and control date: 2008-03-26 journal: am j infect control doi: 10.1016/j.ajic.2008.01.002 sha: doc_id: 279640 cord_uid: n391v32y nan opportunities and challenges in utilizing electronic health records for infection surveillance, prevention, and control there are unique patient safety challenges in the prevention and control of health care-associated infections (hai). it is estimated that approximately 2 million hai occur every year in the united states, and each infection increases the risk of death by as much as 6 times. 1 this amounts to an estimated 90,000 deaths annually and $4.5 billion excess health care costs. 2, 3 the emergence of specific multidrug-resistant organisms (mdro), the growing number of immunocompromised patients, and the increasing number of invasive procedures and medical device implantations are posing new challenges for infection control. how many of these hai are preventable remains unclear, but payers such as the centers for medicare medicare & medicaid services have already enacted rules that preclude reimbursement for certain conditions that are attributed to hospitalization, eg, catheter-associated urinary tract infections. 4 initiatives such as the institute for healthcare improvement's 100,000 and 5 millions lives campaigns, the joint commission's national patient safety goals, and guidelines for public reporting of hai reflect growing concern over hai and the need for their prevention. 3, 5 many such initiatives are evidence based and have shown to reduce the rate of hai. for example, adherence to the ''bundle'' (hand hygiene, full-barrier precautions during insertion of catheter, using chlorhexidine antiseptic to clean the skin, avoiding the femoral site, and removing unnecessary catheters) was recently shown to reduce significantly the rates of catheter-related bloodstream infections among patients receiving care in intensive care units. 5 however, creating a successful culture of safety requires a significant investment in both education of health care personnel and infrastructure support. currently, a third of all hospitals have less than 1 recommended ratio of infection control professionals (icps) to patient beds (a ratio of 0.8 to 1.0 icp for every 100 occupied acute care beds). 6 hence, icps struggle to keep up with essential infection control tasks because of other competing responsibilities and lack of adequate resources. without deploying resources that allow for automation, it may not be possible for icps to collect more and richer data (such as catheter-days and details on adherence to the bundle for catheter insertion) and at the same time design specific interventions required for pay-for-performance initiatives. emerging information technology such as electronic health records (ehrs) can help meet these challenges. they can facilitate automated collection of surveillance data, provide risk-adjusted patient outcomes, and facilitate infection control interventions at the point of care. in 2004, the us department of health and human services declared the start of a ''decade of health information technology (health it)'' (appendix) and called for universal ehr adoption by 2014. the increased adoption of ehrs and related health it provide a unique opportunity for icps and infection diseases specialists to automate manual processes and address the growing challenge of hai and guidelines for public reporting. the present paper is an awareness and advocacy paper from the healthcare infection control practices advisory committee (hicpac), which provides advice to the department of health and human services and the cdc regarding surveillance, prevention, and control of hai and related occurrences (http:// www.cdc.gov/ncidod/dhqp/hicpac_charter.html). the paper should not be construed as a standard of care or guideline but as a viewpoint document that aims to (1) provide a conceptual overview of opportunities in utilizing ehrs for infectious disease management, in its most simple form, ehr can be defined as computerization of health record content and associated processes. the term ehr has often been used interchangeably with emr (electronic medical records) even though there are minor but significant differences between the 2 terms. emr is the older term in use and is often associated with electronic patient record systems within an institution. ehr is usually considered the term most reflective of the actual patient experience of receiving health care across institutions. we chose to use the term ehr instead of emr to reflect the growing consensus toward a need for interoperable electronic records. as part of a national effort to encourage the adoption of ehrs, an institute of medicine panel has identified a set of 8 core functions that ehrs should perform to promote greater safety, quality, and efficiency in health care delivery (fig 1) . 7, 8 health information and data, results management, electronic communication, and administrative processes are either built-in or readily supported by the majority of the existing ehrs. health information and data and results management allow for an efficient view of patients' past records including medications, allergies, past admissions, and laboratory and microbiology results. electronic communication enables better coordination of care plan among multiple providers and ancillary services as well as timely notification of critical patient data. administrative processes such as scheduling and billing increase the efficiency of heath care organizations, provide timely service to patients, and decrease the paperwork. 7 order management, clinical decision support, patient support, and population health functions have the potential for a more direct impact on infectious disease management, surveillance, prevention, and control but are not generally essential components of all present day ehrs. order management includes functions such as computerized physician order entry (cpoe), which allows electronic entry of laboratory, medications, and radiology orders instead of orders being recorded on paper sheets or prescription pads. the electronic entry allows clinical decision support (cds) functions to compare the order against standards for dosing, allergies, and others and warn the physician about potential problems. patient support means providing tools such as patient portals or personalized health records (phrs), which give patients access to their health records, provide patient education, and help patients carry out home monitoring and self-testing. this can empower patients and help improve control of chronic conditions, such as diabetes and congestive heart failure. reporting and population health management support the use of already collected electronic data in ehr for uses other than clinical care. quality management, outcomes reporting, and infectious disease surveillance are included in this category. although the benefits of health information, result management, electronic connectivity, and administrative support activities in terms of 24/7 chart access and better availability of the data are apparent and well understood, cpoe and cds when customized and utilized appropriately can also have a direct and significant impact on patient care. cpoe can support process improvement, increase accuracy and legibility of the order, and integrate cds into the order-entry process. 9,10 cds can provide alerts for drug-drug, drug-allergy, and drug-food interactions based on routinely updated drug formularies. in addition, cds also includes reminders, prompts, and alerts to improve compliance with best clinical practices and hyperlinks that can provide context-specific drug or disease information to the provider at the point of care. studies have shown that properly designed cpoe and cds can lead to as much as 85% reduction in serious medication errors. 10 other system-wide benefits from fully functional ehrs include increased compliance with preventive care guidelines, better coordination and management of chronic conditions, improvement in quality indicators for pay-for-performance initiatives, reduced staff time spent on paperwork, reduced number of duplicate or unnecessary laboratory and imaging orders, and increased accuracy and timeliness of billing. 11 to support infectious disease (id) management, cds can be customized to incorporate patient-specific clinical information such as laboratory or microbiology information along with diagnostic, demographic, and clinical guidelines. this allows for several modes of decision support including alerts for critical laboratory values and recommendations for best antibiotic practices. figure 2 shows a cds where information from patient and a knowledge base feed into an inference engine (a software that uses different rules to draw conclusions) to generate a computerized alert that specifies the need for isolation and a negative-air room for a patient that is suspected to be infected with mycobacterium tuberculosis. cds can also be customized to generate reminders to enhance vaccination rates and preventive screening that have shown to be more effective and less expensive than the paper-based reminders. 11, 12 it is estimated that such computerized reminders to providers at the point of care can lead to a 6.1% to 28.4% increase in preventive health activities such as pneumococcal and influenza vaccinations. 12 cds can also help address the persistent problem of inappropriate antimicrobial prescribing that can promote antimicrobial resistance. for example, evans et al reported the use of an antiinfective-management program that recommended antimicrobials for patients admitted in intensive care unit and provided warnings and immediate feedback. 13 the use of the program led to significant reductions in orders for antibiotic-susceptibility mismatches (12 vs 206, respectively, p , .01) and in adverse events caused by antiinfective agents (4 vs 28, respectively, p , .02). in addition, patients who always received the regimens recommended by the computer program had reduced length of the stay (adjusted mean, 10.0 vs 12.9 days, respectively; p , .001) and total hospital costs (adjusted mean, $26,315 vs $35,283, respectively; p , .001). in a separate study, the authors reported that the percentage of patients having surgery who received appropriately timed preoperative antimicrobial prophylaxis increased from 40% to 99.1%, and the antibiotic-associated adverse drug events decreased by 30%. during the study, antimicrobial resistance patterns were stable, and mortality rates decreased from 3.65% in 1988 to 2.65% in 1994 (p , .001). the authors concluded that computer-assisted decision support programs can improve antibiotic use, reduce associated costs, and stabilize the emergence of mdro. 14 in summary, cpoe and cds can decrease medication errors by increasing accuracy and legibility of the physician orders and providing alerts for drugdrug, drug-allergy, and drug-food interactions. in addition, they can help reduce inappropriate antimicrobial prescribing, which is one of the leading causes of adverse drug events and antimicrobial resistance. these tools can be also customized specifically to improve isolation practices for those infected with mdro or active contagious diseases. surveillance is defined as a comprehensive method of measuring outcomes and related processes of care, analyzing the data, and providing information to members of the health care team to assist in improving those outcomes. 15, 16 manual methods to identify potential hai cases by chart reviews, entering data, and looking for associations can be inefficient, labor intensive, and error prone. 17 ehrs can automate many of these processes. if properly designed, ehrs and related health it can also help in data analysis by identifying abnormal distributions of variables from large interrelated databases. 18 this has shown to be more efficient (requiring one third to one sixth the amount of time required by standard surveillance methods) and effective in screening potential outbreaks as well as finding and reporting endemic hai. 18, 19 with current emphasis on mandatory reporting of hai and requirement by some states to perform house-wide surveillance, ehrs and related information technologies provide a unique opportunity to support the paradigm shift to automated surveillance strategies, which allow icps to minimize time spent finding hai and to maximize time spent preventing them (fig 3) . 20 ehr-supported surveillance has the potential for being a more proactive approach compared with traditional techniques for case finding by which data are collected post hoc after the infection or outbreak has happened. for example, pittet et al used their hospital information system to generate a ''readmission alert'' to icps that informed them about a readmission to the hospital of any patient previously colonized or infected with mrsa. 21 during the first 12 months of application, delayed recognition of readmitted mrsa carriers decreased significantly, and the proportion of mrsa patients recognized at the time of admission to the hospital increased from 13% to 40% (p , .001). the effectiveness of this approach has also been reported by gransden et al, who found that two thirds of patients readmitted to the hospital were not known to be previously infected by the admitting staff and were instead alerted by the computerized system. 22 early identification of patients at risk, such as at the time of hospital admission, allows icps to conduct active surveillance and take prompt contact precautions if needed to prevent nosocomial spread. 23 this strategy has been found to be cost-effective and supported by institutions that do not have comprehensive ehrs can benefit from utilizing web-based systems and other health information technologies for hai prevention, control, and surveillance. for example, the chicago antimicrobial resistance project (carp) reported a successful use of the clinical data warehouse to automate measurement of performance indicators and surveillance for infection control. 25 the clinical data warehouse was designed to store data collected from both nonelectronic sources (eg, manually abstracted data from patient medical records and scanned surveys) and electronic data from many different hospital information systems: pharmacy, laboratory, radiology, medical records, and emergency department. the carp data warehouse has been used in regular surveillance activities such as determining rates of hai, central venous catheter use, and antimicrobial resistance as well as for quality improvement activities. these investigations as well as others highlight potential applications that utilize increased convergence between ehrs and laboratory and pharmacy information systems for electronic reporting of endemic and syndromic conditions in the population. 26, 27 a recent report described a stand-alone electronic anesthesia record system and 6 sigma methodology to improve successfully the timing of perioperative antibiotic prophylaxis before surgical incision. 28 the time interval for antibiotic administration before surgical incision decreased from a preintervention mean of 88 minutes (95% ci: 56-119 minutes) to 38 minutes (95% ci: 25-51 minutes) (p , .01). a recently published study reported using an intranet-based tool for improvement and documentation of influenza vaccination and declination rates of 20,170 health care personnel in an 1100-bed hospital. with an estimated direct cost of $4800, the intranet-based tool was associated with a significant increase in documented vaccination rates from 38% to 55% in 1 year. 29 there are commercial surveillance technology software that can work with ehrs or other health information systems to help automate identification of hai using algorithms that analyze laboratory results, admission records, and possible pathogens. the majority of these can be readily implemented within a few months. some of these products can simultaneously track infection data and combine it with pharmacy data such as antibiotic use to generate antibiotic utilization and resistance reports and recommend targeted and cost-effective antibiotic selections at the point of care. a few can even provide real-time infection risk profiles via an electronic clinical dashboard that helps alert clinicians to specific patients who may be at high risk for infection. 18, 20 in addition, some may facilitate efficient and timely reporting of notifiable conditions to public health agencies. 30 more detail on commercial surveillance technology solutions is reported elsewhere (www.manageinfection.com/10-06/mic1006w26. pdf). because these solutions may require significant capital investment and customization, a thorough analysis is recommended to find the best fit for an organization. there are also cdc-led initiatives for endemic hai and outbreak surveillance. for example, the national healthcare safety network (nhsn) is a web-enabled surveillance system designed for surveillance of hai in health care facilities. 31, 32 enrollment in the nhsn is free and currently open for hospitals and outpatient hemodialysis centers. the nhsn allows entry of event and denominator data for both device-and procedureassociated events as well as data entry for microbiology susceptibility and antimicrobial use that can be risk adjusted and used for interfacility comparisons and quality improvement activities (fig 4) . in addition, the nhsn plans to implement modules that will focus on mdros, central line insertion practices, and high-risk patient influenza vaccination. there are an increasing number of states that are adopting nhsn participation as a platform for responding to legislative mandates for public reporting. during the global epidemic of severe acute respiratory syndrome (sars), the cdc successfully utilized web-based tools to rapidly establish multiregion syndromic surveillance. a total of 27 emergency departments reported syndrome frequencies from more than 146,000 patient encounters, confirming the usefulness of web-based systems for triage and outbreak surveillance. 33 currently, the cdc's biosense application is aimed at detecting early signs of disease outbreaks by gathering real-time data related to illness syndromes and clinical severity and confirmed clinical findings from hospitals to cdc. 34 the application provides electronic ''views,'' analytics, and reports to inform outbreak surveillance at national, state, and local public health levels and aims to reduce burden of clinical data collection during the early outbreak investigation. because each health care organization must tailor its surveillance according to its population characteristics and outcome priorities, it helps to list clearly the purpose and objectives of the surveillance system and indicate its level of usefulness to the organization. the cdc has published guidelines for evaluating public health surveillance systems that can also be applied to commercial surveillance software and information systems at individual health care facilities. 15 after determining the objectives of the surveillance systems, evaluation should assess system attributes, including simplicity, flexibility, data quality, acceptability, sensitivity, predictive value positive, representativeness, timeliness, and stability. it is also useful to assess whether the system uses data exchange and messaging standards that can automate data collection from ehrs and existing health it and facilitate reporting to public agencies. although automation enhances efficiency, it does not by itself lead to more accurate data. overt reliance on administrative or billing databases can lead to inaccurate and misleading reporting. 35, 36 hence, due diligence should be exercised to confirm the accuracy of data and associated processes so as to meet the requirements of an epidemiologically sound surveillance system. 15, 16 transformation in current practice of id management, surveillance, prevention, and control will not occur without proactive involvement of id specialists and icps in health it initiatives at the local, regional, or national level. awareness about health itand its adoption and advocacy is key to successfully leveraging ehrs and related information technologies. the icps and id specialists need to first become aware of the changing landscape in the field of infection control; the opportunities created by modern health it to realize the new paradigm; and the evolving role of health it in surveillance, prevention, and control of hai. it is necessary to become familiar with current and planned it initiatives in ones own health care institution and at regional, state, and national levels to promote synergy and prevent duplication of efforts. regular communication and dialogue with health care institutions' chief informatics officer or chief technology officer could be the initial step in starting to know more about an institution's short-and longterm health it strategies. at present, only 1 in 4 physicians use some type of ehrs, and fewer than 1 in 10 use a comprehensive ehr system. the return on investment and incremental benefit of ehrs increase when they can also be utilized for id management, surveillance, prevention, and control. because ehrs differ with respect to their features, it is important for icps and id specialists to know which ehr has functionalities that can support their practices (see table 1 ). icps in institutions that have already adopted ehrs or made the decision to do so should, as subject experts, help with the customization of the ehrs to support best practices for id management and surveillance. there needs to be advocacy to decision makers at the federal, state, and local levels for the promotion of a synergistic strategy to leverage it for id management and surveillance. currently, many of the ehrs are not prepackaged with decision support capabilities and the surveillance solutions required for id management and control. this requires many institutions to either customize the ehrs or resort to stand-alone commercial surveillance systems to meet their requirements. hicpac plans to work closely with standard developing organizations such as health level 7 (hl7) to drive standards and support for features and functions that enable id management and surveillance. it is important to realize that ehr is not a panacea but an important and critical tool in patient-centered health care. there are many significant barriers to widespread use of ehrs that could limit its potential to transform our practices in the 21st century. most notable are the cost of technology, the lack of standards to support data exchange, and the potential for adverse consequences if not implemented correctly. cost is the cited as the biggest impediment to the widespread implementation of health it. it has been estimated that universal ehr adoption and interoperability will cost $156 billion in capital investment over 5 years and $48 billion in annual operating costs. 38 in addition, there needs to be continued investment in human capital that has a diverse skill set (programming, database administration, network support, project management, data mining, statistics, clinical informatics, and others) if full benefits of ehr are to be realized. another impediment to widespread health it adoption is the lack of standards that allow for nationwide interoperability. hence, the fact that a patient has had mrsa in one institution can be completely missed by another institution even if both institutions have ehrs. furthermore, many ehrs lack functions that support cds customization or allow for reporting, population health, or surveillance. in 2004, the certification commission for healthcare information technology (cchit) was formed to create certification criteria for health care it products, including ehrs (www.cchit.org). cchit provides a list of ehrs that are certified to have these functions so that end users can expect to leverage them for their clinical, research, and surveillance needs. there is also growing concern that technology, if not properly utilized, can lead to unintended consequences such as more/new work for clinicians, untoward changes in communication patterns, generation of new kinds of errors, and overdependence on the technology. 39 any new implementation of health it needs to be rigorously tested and regularly evaluated to prevent such unintended consequences of technology. each health care infection control program is distinctive, but the expectation is that each is based on sound epidemiologic principles and meets the standards required to address the growing problem of hai. it is essential that informatics principles be widely understood if icps are to develop the capacity to manage and utilize information systems to address hai and other adverse events associated with the delivery of health care. ehr-based automated surveillance, reporting, and hai epidemiology can allow icps to focus their efforts toward education and interventions rather than manual data gathering. at the same time, ehrs can promote better antimicrobial prescribing, enhance immunization practices, and help in prompt identification and isolation of patients with mdro. id specialists and icps need to become aware of emerging technologies and get involved in advocacy and adoption efforts at local, regional, and national levels to leverage the opportunities created by current health it initiatives. glossary biosense: biosense is the cdc national initiative designed to improve the nation's capabilities for realtime biosurveillance and situational awareness. by providing access to data from hospitals and health care systems in major metropolitan cities across the nation, biosense is connecting existing health information to public health in a way not previously possible (http:// www.cdc.gov/biosense). cdr, clinical data repository: cdr is a database that consolidates data from a variety of information sources to present a unified view for a clinician or researcher. typical data types that are often found within a cdr include the following: laboratory test results, patient demographics, pharmacy information, radiology reports and images, pathology reports, hospital admission/discharge/transfer dates, icd-9 codes, discharge summaries, and progress notes. cpoe, computerized provider order entry: a computer application that allows a physician's orders for diagnostic and treatment services (such as medications, laboratory, and other tests) to be entered electronically instead of being recorded on order sheets or prescription pads. cds, clinical decision support: computer tools or applications to assist physicians in clinical decisions by providing evidence-based knowledge in the context of patient-specific data. examples include drug interaction alerts at the time medication is prescribed and reminders for specific guideline-based interventions during the care of patients with chronic diseases. erx, electronic prescribing: a type of computer technology whereby physicians use handheld or personal computer devices to review drug and formulary coverage and to transmit prescriptions to a printer or to a local pharmacy. e-prescribing software can be integrated into existing clinical information systems to allow access to patient-specific information to screen for drug interactions and allergies. health it, health information technology: the application of information processing involving both computer hardware and software that deals with the storage; retrieval; sharing; and use of health care information, data, and knowledge for communication and decision making. a central element of health it is the patient's electronic health record. hl7, health level seven: a standard setting organization for health it specifically in clinical and administrative data (www.hl7.org). interoperability: the ability of a system or a product to work with other systems or products without special effort on the part of the customer. nhin, national health information network: describes the technologies, standards, laws, policies, programs, and practices that enable health information to be shared among health decision makers, including consumers and patients, to promote improvements in health and health care (http://www.hhs.gov/healthit/ healthnetwork/background). nhii, national health information infrastructure: often used synonymously with nhin. nhii came before nhin and is an acronym that encompasses all of the necessary components needed to make ehrs interoperable. nhin, as the name suggests, refers to both the physical and national network needed for interoperability to occur. nhsn, national healthcare safety network: a webenabled surveillance system designed for use by the cdc and its health care partners for the purpose of improving patient and health care worker safety. nhsn merges 3 predecessor surveillance systems maintained by the division of healthcare quality promotion (dhqp) in the cdc's national center for prevention, detection, and control of infectious diseases (ncpdcid). these were the national nosocomial infections surveillance (nnis) system, the national surveillance system for healthcare workers (nash), and the dialysis surveillance network (dsn). onchit, office of the national coordinator for health information technology: provides leadership for the development and nationwide implementation of an interoperable health information technology infrastructure to improve the quality and efficiency of health care and the ability of consumers to manage their care and safety. the national coordinator for health information technology serves as the health and human services secretary's principal advisor on the development, application, and use of health information technology (www.hhs.gov/healthit). phr, personal health record: an electronic application through which individuals can maintain and s44 vol. 36 no. 3 supplement 1 manage their health information (and that of others for whom they are authorized) in a private, secure, and confidential environment. rhio, regional health information organization: a multistakeholder organization that enables the exchange and use of health information, in a secure manner, for the purpose of promoting the improvement of health quality, safety, and efficiency. officials from the us department of health and human services (hhs) see rhios as the building blocks for the national health information network (nhin). when complete, the nhin will provide universal access to electronic health records. estimating health care-associated infections and deaths in us hospitals nosocomial infection update guidance on public reporting of healthcare-associated infections: recommendations of the healthcare infection control practices advisory committee medicare plans to stop paying for 6 hospital-acquired conditions. am-news staff an intervention to decrease catheter-related bloodstream infections in the icu staffing requirements for infection control programs in us health care facilities: delphi project key capabilities of an electronic health record system: letter report using technology to promote gastrointestinal outcomes research: a case for electronic health records computer physician order entry: benefits, costs, and issues the impact of computerized physician order entry on medication error prevention effects of computerized clinical decision support systems on practitioner performance and patient outcomes: a systematic review improving preventive care by prompting physicians a computer-assisted management program for antibiotics and other antiinfective agents implementing antibiotic practice guidelines through computer-assisted decision support: clinical and financial outcomes updated guidelines for evaluating public health surveillance systems: recommendations from the guidelines working group recommended practices for surveillance: association for professionals in infection control and epidemiology (apic), inc statewide system of electronic notifiable disease reporting from clinical laboratories: comparing automated reporting with conventional methods harris ad. preliminary assessment of an automated surveillance system for infection control an evaluation of surveillance methods for detecting infections in hospital inpatients infection rate reporting and the ehr miles apart: a puzzle wrapped up in a riddle. healthcare purchasing news automatic alerts for methicillin resistant staphylococcus aureus surveillance and control: role of a hospital information system computerized detection of re-admission of patients with mrsa screening high-risk patients for methicillin-resistant staphylococcus aureus on admission to the hospital: is it cost-effective? shea guideline for preventing nosocomial transmission of multidrug-resistant strains of staphylococcus aureus and enterococcus development of a clinical data warehouse for hospital infection control hospital electronic medical record-based public health surveillance system deployed during the 2002 winter olympic games improving infection control, prevention, and surveillance: using the electronic health record (ehr) in a 370-bed acute care hospital six sigma methodology can be used to improve adherence for antibiotic prophylaxis in patients undergoing noncardiac surgery novel use of the intranet to document health care personnel participation in a mandatory influenza vaccination reporting program a review of strategies for enhancing the completeness of notifiable disease reporting the changing face of surveillance for health care-associated infections national healthcare safety network (nhsn) report, data summary for sars surveillance project-internet-enabled multiregion surveillance for rapidly emerging disease biosense: implementation of a national early event detection and situational awareness system administrative data fail to accurately identify cases of healthcareassociated infection comparisons of health care-associated infections identification using two mechanisms for public reporting electronic laboratory reporting for the infectious diseases physician and clinical microbiologist the costs of a national health information network types of unintended consequences related to computerized provider order entry key: cord-295469-5an7836u authors: ijaz, m. khalid; zargar, bahram; wright, kathryn e.; rubino, joseph r.; sattar, syed a. title: generic aspects of the airborne spread of human pathogens indoors and emerging air decontamination technologies date: 2016-09-02 journal: am j infect control doi: 10.1016/j.ajic.2016.06.008 sha: doc_id: 295469 cord_uid: 5an7836u indoor air can be an important vehicle for a variety of human pathogens. this review provides examples of airborne transmission of infectious agents from experimental and field studies and discusses how airborne pathogens can contaminate other parts of the environment to give rise to secondary vehicles leading air-surface-air nexus with possible transmission to susceptible hosts. the following groups of human pathogens are covered because of their known or potential airborne spread: vegetative bacteria (staphylococci and legionellae), fungi (aspergillus, penicillium, and cladosporium spp and stachybotrys chartarum), enteric viruses (noroand rotaviruses), respiratory viruses (influenza and coronaviruses), mycobacteria (tuberculous and nontuberculous), and bacterial spore formers (clostridium difficile and bacillus anthracis). an overview of methods for experimentally generating and recovering airborne human pathogens is included, along with a discussion of factors that influence microbial survival in indoor air. available guidelines from the u.s. environmental protection agency and other global regulatory bodies for the study of airborne pathogens are critically reviewed with particular reference to microbial surrogates that are recommended. recent developments in experimental facilities to contaminate indoor air with microbial aerosols are presented, along with emerging technologies to decontaminate indoor air under field-relevant conditions. furthermore, the role that air decontamination may play in reducing the contamination of environmental surfaces and its combined impact on interrupting the risk of pathogen spread in both domestic and institutional settings is discussed. indoor air can be an important vehicle for a variety of human pathogens. this review provides examples of airborne transmission of infectious agents from experimental and field studies and discusses how airborne pathogens can contaminate other parts of the environment to give rise to secondary vehicles leading air-surface-air nexus with possible transmission to susceptible hosts. the following groups of human pathogens are covered because of their known or potential airborne spread: vegetative bacteria (staphylococci and legionellae), fungi (aspergillus, penicillium, and cladosporium spp and stachybotrys chartarum), enteric viruses (noro-and rotaviruses), respiratory viruses (influenza and coronaviruses), mycobacteria (tuberculous and nontuberculous), and bacterial spore formers (clostridium difficile and bacillus anthracis). an overview of methods for experimentally generating and recovering airborne human pathogens is included, along with a discussion of factors that influence microbial survival in indoor air. available guidelines from the u.s. environmental protection agency and other global regulatory bodies for the study of airborne pathogens are critically reviewed with particular reference to microbial surrogates that are recommended. recent developments in experimental facilities to contaminate indoor air with microbial aerosols are presented, along with emerging technologies to decontaminate indoor air under fieldrelevant conditions. furthermore, the role that air decontamination may play in reducing the contamination of environmental surfaces and its combined impact on interrupting the risk of pathogen spread in both domestic and institutional settings is discussed. © 2016 published by elsevier inc. on behalf of association for professionals in infection control and epidemiology, inc. air, a universal environmental equalizer, affects all living and nonliving forms on planet earth. for humans, it has profound health implications in all indoor environments where we normally spend most of our time. [1] [2] [3] air quality is also forever changing because of the influence of many controllable and uncontrollable factors that are virtually everywhere. indoor air, in particular, can expose us to noxious chemicals, particulates, and a variety of infectious agents, as well as pollen and other allergens. 4, 5 emerging pathogens, such as noroviruses 6 and clostridium difficile, 7 have also been detected in indoor air, with a strong potential for airborne dissemination. pathogens discharged into the air may settle on environmental surfaces, which could then become secondary vehicles for the spread of infectious agents indoors. 8 the possible transmission of drug-resistant bacteria by indoor air adds another cause for concern. 9 a combination of on-going societal changes is adding further to the potential of air as a vehicle for infectious agents. [10] [11] [12] the quality of indoor air is therefore a prominent public health concern 13,14 that requires a clear understanding of the transmission processes for the development and implementation of targeted infection prevention and control measures. 15 although direct and indirect exposure to pathogens in the air can occur by other means, infections from the inhalation and retention, including translocation and ingestion after inhalation of droplet nuclei, are generally regarded as true airborne spread. aerosols of various sizes that contain infectious agents can be emitted from a variety of sources, such as infected or colonized individuals 16 or flushing toilets, and may expose susceptible persons either directly (droplet transmission) or by remaining suspended in the air for inhalation (airborne transmission). 17, 18 contrary to the conventionally held belief, modeling work has redefined the wells evaporation-falling curve, 19, 20 revealing that expelled large droplets could be carried >6 m away by exhaled air at a velocity of 50 m/s (sneezing), >2 m away at a velocity of 10 m/s (coughing), and <1 m away at a velocity of 1 m/s (breathing), leading to potential transmission of short-range infectious agents that contain aerosols. 21 airborne transmission requires that pathogens survive the process of aerosolization and persist in the air long enough to be transmitted to a susceptible host. 22 aerosolized pathogens may settle onto environmental surfaces in the immediate vicinity, leading to genesis of secondary vehicles (fig 1) . 23 this review provides current information on the spread of human pathogens by indoor air, with a focus on the major classes of human pathogens from experimental and field studies, and on emerging air decontamination technologies, including test protocols developed to assess their performance under field-relevant conditions. the study of aerosolized human pathogens requires the ability to produce them experimentally at the appropriate size, store them, and sample them for residual infectious content over a predetermined time period. 13 the equipment must also simulate naturally occurring environmental conditions and the duration of exposure to accurately assess aerosol survivability. 24 various analytical methods and air samplers have been used to characterize airborne pathogens and overcome the challenges of collecting and analyzing them. relevant studies have been reviewed in detail elsewhere. 13, 25, 26 aerosolized microbes must survive the prevailing environmental conditions to potentially infect a susceptible host. 22 multiple factors affect airborne survival of microbes indoors (table 1) . 13, 31 the effect of these factors on different types of microbes varies, and generalizations can be difficult because of differences in the experimental methodologies used. 27 air temperature, relative humidity (rh), and turbulence are among the more important factors affecting the fate and spread of infectious agents indoors. the analysis of air samples for microbes now includes methods that are based on the polymerase chain reaction (pcr). however, pcr-based methods typically cannot differentiate between viable and nonviable microbes. 32 a recent study found that pcr substantially overestimated the quantity of infectious airborne influenza virus, but the differences in infectious versus noninfectious virus over time were similar to data from quantification by plaqueforming units, which determined that virus losses were evident within 30-60 minutes postaerosolization. 32 generally, enveloped viruses survive better at lower rh, but there are many exceptions. 28 other factors that affect aerosol activation in relation to rh include evaporative activity (ie, dehydration, rehydration), surface areas of particles, and ph. 28 although studies with experimental animals have determined the susceptibility to airborne pathogens and the minimal infective inhalation dose of a given pathogen, 25 there are wide variations sources of airborne pathogens indoors and potential for environmental surface contamination. these sources may include humans; pets; plants; plumbing systems, such as operational toilets and shower heads; heating, ventilation, vacuuming, mopping, and air-conditioning systems; resuspension of settled dust; and outdoor air. the yellow and red dots represent human pathogens or harmless microorganisms. adapted with permission from biomed central. 23 in their test design. first, the number of inhaled microbes may not be known or it may be unrealistically high. second, the test protocol may not have fully excluded microbial exposure by means other than inhalation. third, there may be incomplete recording of the environmental conditions (eg, rh, air temperature) to assess their impact on microbial viability. fourth, pertinent differences may exist between laboratory-adapted strains of the tested microbe compared with strains in the field. studies using the actual pathogen aerosolized in body fluids provide the strongest evidence of pathogen survivability. 18 in contrast, field studies face their own set of challenges, which include the noise, bulk, and expense of inefficient air collection devices. 25 moreover, passive impingers may not adequately collect low concentrations of pathogens found in the clinical environment. 33 slit sampling does not impose size exclusion and may be more effective at recovering viable pathogens of any size. 33 from a methodologic perspective, field studies also must control for potential variables, such as air turbulence or human activity in areas proximate to sampling, such that sampling occurs before, during, and after an area is occupied and should include functioning ventilation systems. 34 we have previously reviewed published studies on the airborne spread of viruses of animals and humans. 13, 25 table 2 summarizes key human pathogens with evidence of aerosol transmission. a number of these pathogens causes severe disease, and their classification as high risk by the u.s. centers for disease control and prevention and the world health organization emphasizes the need for appropriate control measures. 18 experimental studies have used surrogates for human pathogenic enveloped and nonenveloped viruses, such as cystovirus (ϕ6) and bacteriophage ms-2, respectively. 35 enteric viruses are transmitted primarily by the fecal-oral route, but airborne transmission has been reported. 13 airborne transmission of norovirus may be possible via aerosolization of vomitus and toilet flushing, which are regarded as potential sources of both indoor air and environmental surface contamination. enteric bacteria and viruses have been recovered from indoor air and environmental surfaces in areas sur-rounding toilets. 18, 36, 37 we reported that aerosolized simian rotavirus sa-11 38 survived best at midrange rh. 39, 40 these results contradicted a prior study by moe and harper, 41 in which the uk strain of calf rotavirus was reported to survive best at low and high rh, but not at high temperature. 41 subsequent studies on human rotavirus, 39 murine rotavirus, and a uk strain of calf rotavirus, aerosolized under the same experimental setup, confirmed the behavior of all strains of rotaviruses are similar in airborne state. 39, 40 furthermore, studies of different picornaviruses (poliovirus type 1 [sabin] and human rhinovirus) and a human coronavirus (an enveloped virus) that used the same experimental conditions produced results that were consistent with the published literature, suggesting that the experimental design did not introduce bias toward the behavior of aerosolized rotaviruses. 39, 42, 43 among the respiratory viruses, influenza virus is present in the air around infected individuals, and airborne transmission via droplet nuclei has been demonstrated in experimental models and in reports of influenza spread on-board aircrafts. 15 low rh favors airborne survival and transmission; however, high air exchange rates facilitate dilution of virus-containing aerosols, regardless of their size. 12 a recent study confirmed recovery of influenza virus from the air emitted by infected persons at distances of 0.5-1.5 m, which could reach the breathing zone of susceptible individuals, including health care workers. 44 surprisingly, and in spite of much study, the exact mode of and the relative importance of various types of vehicles for transmission of rhinoviruses, which are the most frequent cause of the common cold, remain shrouded in mystery. 45, 46 the behavior of experimentally aerosolized rhinovirus type 14, which represents typical picornaviruses (as previously mentioned), 43 coupled with rhinovirus recovery from both indoor air 47 and outdoor air, 48 substantiate the role of air as a vehicle in spread of some of these picornaviruses. taken together, an overall assessment of the available evidence suggests a role for airborne spread 49 and for the role of contaminated hands and environmental surfaces in rhinovirus dissemination. 50 coronaviruses are the second leading cause of the common cold and are also responsible for the severe acute respiratory syndrome (sars) and the middle east respiratory syndrome. 37 sars is thought to be transmitted via direct contact, but airborne transmission is also suspected because the virus has been detected in air samples that were collected from rooms where a patient was recovering from sars. 18, 33 the virus is spread through droplets and can remain viable on surfaces for several days at room temperature. the use of aerosol-generating procedures, such as intubation, bronchoscopy, and oxygen delivery vents, may promote dispersal of sars via enhanced release in mists of exhaled pulmonary gases. 34, 51 our earlier work on the behavior of aerosolized human coronaviruses 229e further substantiates the potential role of air in their aerial spread. 39 aerosol transmission of the ebola virus is biologically plausible. 18 the virus is present in saliva, stool, blood, and other body fluids; therefore, it could be aerosolized through symptoms associated with infection or via health care procedures. the ebola virus has been shown to survive in the air when the half-life of the virus ranged from 15 (zaire ebola virus) to 24 minutes (reston ebola virus), and the time for 99% biologic decay of the aerosolized virus held in rotating drum (at 50%-55% rh and 22°c ± 3°c) was estimated to be between 104 and 162 minutes. additionally, infection of rhesus monkeys via experimentally aerosolized ebola virus has also been reported. 52 these findings raise concerns for aerosol transmission and control of this serious pathogen; however, thus far, there is no clear evidence for the airborne spread of this virus in humans. 18 epidemiologic evidence indicates transmission is associated with direct physical contact or contact with body fluids; however, the possibility of aerosolized spread has been postulated by ebola virologists. 18, 53 bacteria approximately one-third of humans carry staphylococcus aureus, with the anterior nares as a common site of colonization, 54 and environmental contamination plays an important role in the transmission of methicillin-resistant s aureus. shedding of the bacteria is highly variable, but transmission likely occurs via skin squames that settle out on environmental surfaces in the vicinity. smaller particles may remain airborne, particularly if there is air turbulence. 54, 55 an important characteristic of the staphylococci is their ability to survive over a wide range of temperatures, rh, and exposure to sunlight. 54 mycobacterium tuberculosis is transmitted via droplet nuclei expectorated from infected persons during coughing, sneezing, and talking. 18, 34 control measures include expensive negative-pressure ventilation and less expensive, but climate-dependent, natural ventilation. 56 upper-room ultraviolet (uv) light or negative air ionization may help reduce the airborne spread of m tuberculosis. 56 nontuberculous mycobacteria are found in soil and water sources and can form biofilms under domestic environments, such as shower heads. 57 transmission to humans is uncertain, but droplet aerosolization is a suspected route of pulmonary disease, with shower heads considered a common source. 57, 58 contamination of hospital water supplies and medical equipment are suspected in nosocomial outbreaks of disease. 59 similarly, legionella spp become airborne by active aerosolization of contaminated water and form biofilms in air conditioning systems. 34 legionella-like amoebal pathogens are a subset of bacteria that grow within amoebae and often are coinfectious agents with other bacteria and fungi. 60 clostridium difficile spores have been recovered from the air near symptomatic patients, especially those with recent-onset diarrhea. 61 air samples were positive for c difficile in 70% of patients, and the highest levels of surface recovery were in areas closest to the patient. 7 the isolates recovered from the air were indistinguishable from those recovered from fecal samples and from the environment in the same settings. 7 additionally, c difficile has been recovered after toilet flushing, and leaving the lid open when flushing increases contamination of surrounding environmental surfaces. 61 airborne infection of bacillus anthracis is affected by environmental factors that include room size, ventilation rate, and host factors, such as pulmonary ventilation rate. 62 secondary aerosolization of viable b anthracis spores was reported after contamination of a u.s. senate office, with >80% of particles being in the respirable size range of 0.95-3.5 μm. 14 as ubiquitous microorganisms, fungi pose a health threat in indoor environments. 29 fungal infections can be particularly serious in immunocompromised patients, 63 especially airborne spores of aspergillus spp that are blown in from natural ventilation sources. 27 fungal spores are aerosolized from municipal water supplies and dust and can be effectively transported over long distances by wind and air currents. 63, 64 the evolution of the fungal spore has enabled them to travel long distances and be more capable of withstanding environmental insults. 27 the most important factor of fungal growth in indoor environments is humidity 65 ; therefore, control measures include dehumidification of the air and high-efficiency particulate arrestor filtration. 27 recent research suggests that airborne fungal particles are heterogeneous and comprise spores and submicrometer fragments. 66, 67 these fragments are of significant interest with regard to health because they remain in the air longer and are easily inhaled. there are also a variety of fungal components that have been identified in air, including mycotoxins, ergosterols, glucans, and microbial volatile organic compounds, and these require unique analysis methods. 64 taken together, these findings provide a foundation for the definition of sick building syndrome. 68 high humidity within sick houses and buildings allows for growth of fungi indoors, particularly species of aspergillus, penicillium, and cladosporium and stachybotrys chartarum, an indoor mold that was associated with sick building syndrome several decades ago. 64, 68, 69 these fungi can be found in dust, furniture, carpets, and ventilation systems at concentrations ranging from 0-1,000 colony-forming unit (cfu)/m 3 . 64 in fact, carpet has been described as a sink for fungi, but it is also a source for resuspension of fungal particles into the air. 64 various respiratory conditions (eg, wheeze, cough, asthma) have been linked to fungi and their biologic components in the indoor environment. 64 fungal species found outdoors include cladosporium and alternaria spp, which are responsible for triggering hypersensitivity reactions, including rhinitis, sinusitis, and asthma. 27, 64 the clear recognition of indoor air as a vehicle for pathogens has incurred a corresponding upsurge in the marketing of products and technologies with claims for safe and effective decontamination of air. 70 although many technologies are available for environmental surface decontamination, the number and variety of those for decontamination of indoor air remain limited and of questionable veracity ( table 3 ). the air-decontaminating claims of many such technologies are not based on testing under field-relevant conditions with pathogens relevant to human health, and scientifically valid and standardized protocols to generate field-relevant data for label claims for review by regulatory and public health agencies and the public at large remain unavailable. here, we address this gap in the development of a test platform for standardized testing of commercially available devices for decontaminating indoor air of vegetative bacteria that represent airborne human pathogens. we know of only one guideline that directly relates to this topic. 71 it specifies the size of a sealed enclosure for experimental contamination of the air with aerosols of vegetative bacteria to assess technologies for their temporary reduction. therefore, the text that follows relates directly to that guideline. the studies of microbial survival in indoor air, as well as proper assessment of methods for its decontamination, emphasize numerous challenges and highlight the need for specialized equipment and protocols. proper expertise and suitable experimental facilities for such investigations remain uncommon. several of the available sites with testing claims are neither experienced in, nor equipped to conforming with, the u.s. environmental protection agency's (epa) guidelines on testing the sanitization of indoor air. 71 based on our considerable experience in the study of airborne human pathogens, 13, 25, 39, 43, 72 we have built an aerobiology chamber (fig 2) designed to meet the requirements of the epa guidelines and have used this to study the effects that a variety of air decontamination technologies have on the airborne survival and inactivation of vegetative bacteria, viruses (bacteriophage), and bacterial spore-formers (sattar et al, unpublished data) . additional details about the operational aspects of the aerobiology chamber, described elsewhere, 73 are discussed briefly. any meaningful assessment of air decontamination requires that the aerosolized challenge microbe remain viable in the experimentally contaminated air long enough to allow for proper differentiation between its biologic decay or physical fallout and inactivation or removal by the technology being assessed. therefore, initial testing is required to determine the rate of biologic decay of the test microorganism(s) under the experimental conditions to be used for testing potential air decontamination technologies. for this, the test microorganism(s) was aerosolized into the chamber, and 2-minute air samples were collected at different intervals using a slit-to-agar (sta) sampler over an 8-hour period. the culture plates were incubated at 36°c ± 1°c, the cfu on them was recorded, and the data were analyzed to determine the rate of biologic decay. the results of the tests on the airborne survival of 3 types of vegetative bacteria are shown in figure 3 . acinetobacter baumannii (atcc 19606; atcc, manassas, va) proved to be the most stable in air, followed by s aureus (atcc 6538; atcc) and klebsiella pneumoniae (atcc 4352; atcc). three types of commercially available indoor air decontamination devices that were based on uv light and high-efficiency particulate arrestor filtration were tested for their ability to reduce the levels of viable bacteria in the air of the chamber ( table 4 ). the air within the chamber was first experimentally contaminated with aerosolized test bacterium suspended in a soil load. the test device, placed inside the chamber, was remotely operated, and samples of the chamber air were collected directly onto petri plates using sta and were incubated for cfu determinations. as shown in figures 4a and 4b , the air decontamination devices that were tested could achieve a 3-log10 reduction in viability of s aureus and k pneumoniae in 38-45 minutes (table 5 ). so far, such testing has been conducted only once with a baumannii using device 1, and as the data presented in figure 5 show, it reduced the viability of a baumannii by 3 log10 in 38 minutes (table 5) . in this experiment, device 1 was tested for its ability to manage ongoing fluctuations in the microbiologic quality of indoor air. a suspension of s aureus was nebulized into the chamber at 3 separate time points, while the device operated continuously. as shown in figure 6 , the device's efficacy after the 3 challenges with aerosolized bacteria was almost the same. the times at which the device demonstrated 3-log10 reductions after each nebulization were found to be 40, 39.5, and 40.9 minutes. the mean of the 3-log10 reduction times was 40.13 ± 0.71 minutes, giving an average biologic decay rate of aerosolized bacteria of 0.0753 ± 0.0024 cfu/m 3 /min after the 3 nebulizations. as previously mentioned, larger particles of aerosolized pathogens often settle onto environmental surfaces in the immediate vicinity, leading to contamination as a secondary vehicle of transfifteen sterile plastic plates were placed in groups of 3 on the floor of the aerobiology chamber, with one set in each of the 4 corners and one in the center. the lids of the plates were removed. a suspension of s aureus in a soil load was nebulized into the chamber with the muffin fan operating for 5 minutes to evenly distribute the airborne bacterial particles. a 2-minute air sample was then collected from the chamber using an sta sampler to determine the initial level of airborne contamination. ten minutes were allowed to elapse for circulation of the airborne bacteria in the chamber. the muffin fan was then turned off and the airborne bacteria were allowed to settle for 30 minutes. at the end of this period, the petri plates were retrieved and eluted for cfu to determine the titer of microbial contamination deposited on each one. such testing allowed us to determine the levels of airborne bacteria that could settle on the plates without air decontamination procedures. the experiment was repeated in exactly the same manner, but with the test device in the chamber activated and allowed to work for 45 minutes. at the end of this period, the petri plates were retrieved and eluted for cfu to determine the titer of microbial contamination deposited on each plate. the results indicated that the nebulization of the microbial suspension for 10 minutes produced 4.7 log10 cfu/m 3 of air in the chamber. the average level of cfu on the control and test petri plates held in the chamber was 200 ± 110 and 8.3 ± 8.9, respectively. the device could reduce the contamination of the plates from airborne bacteria by 95% as compared with the controls. recognition that human pathogens can be transmitted via indoor air emphasizes the need for the development of control procedures that limit exposure and reduce the risk of infection in susceptible individuals. this need is heightened by an increase in the aging population and numbers of the immunosuppressed. we must also be prepared for an intentional or accidental release of infectious aerosols. standardization of sampling and analytical methods is crucial to developing an understanding of airborne pathogens 26 and technologies for their effective control. we have described the creation and application of an aerobiology test chamber that complies with the relevant guideline of the epa. 71 the chamber was successfully used (1) to study the airborne survival of 3 types of vegetative bacteria under ambient conditions; (2) to test the ability of 3 commercial indoor air decontamination devices to abate experimentally generated aerosols of 3 types of vegetative bacteria; (3) to test one of the devices for its ability to deal with repeated microbial challenge with vegetative bacteria in simulation of situations in which indoor air is contaminated on an on-going basis; and (4) to test one of the air decontamination devices for its effectiveness in reducing the level of microbial contamination of environmental surfaces as a function of reducing airborne bacteria. each of these experiments was completed successfully, thereby demonstrating the suitability of the aerobiology chamber and the protocols for aerosol generation and sampling. the use of the sta sampler proved particularly effective for providing event-related information on the levels of viable bacteria in the air of the chamber. the testing with a baumannii clearly demonstrated that it is more suitable than k pneumoniae as a surrogate for gram-negative bacteria. a baumannii is not only a relevant airborne pathogen that is more resistant to aerosolization, but it also is more stable in the airborne state. 74 therefore, it is recommended that it be considered as an alternative for k pneumoniae by regulatory agencies, such as the epa, for testing and registration of air decontamination technologies. table 5 regression coefficients, p values comparing decay rates of efficacy tests with stability in air, and times required to achieve 3 log10 reductions device the experimental facility and test protocols described here are suitable for work with other types of airborne human pathogens, such as viruses, fungi, and bacterial spore formers. the aerobiology chamber also could be readily adapted to assess emerging technologies of indoor air decontamination. although the work reported here was performed in a sealed and empty chamber, as specified in the epa guidelines, the aerobiology chamber can be modified to represent air exchanges, and furniture can be introduced to simulate a typical room under both domestic and institutional settings. air, in general, is crucial to the establishment and maintenance of the indoor microbiome, and the continual redistribution of microbes indoors occurs at the air-surface-air nexus. although classic airborne spread of pathogens occurs via droplet nuclei, droplets can potentially contaminate environmental surfaces, depending on their size and prevailing environmental conditions, thereby creating secondary vehicles for pathogens. therefore, targeting airborne pathogens could potentially provide an additional advantage by reducing environmental surface contamination. our preliminary findings indicate that a reduction in the level of viable airborne bacteria using active air decontamination can also reduce bacterial contamination on environmental surfaces in the same setting. therefore, targeting airborne pathogens could entail additional benefits, such as preventing or reducing the deposition of harmful microbes on secondary vehicles that include frequently touched environmental surfaces and also preventing or reducing their resuspension from these surfaces back into the air via a variety of indoor activities (fig 1) . 8, 12, 17, 75, 76 further studies should investigate the role air decontamination may play in reducing the contamination of environmental surfaces and its combined impact on interrupting the risk of pathogen spread in both domestic and institutional settings. aerobiology and its role in the transmission of infectious diseases hospital airborne infection control a comparative study on the quality of air in offices and homes bioaerosols in indoor environment-a review with special reference to residential and occupational locations schools, office buildings, leisure settings: diversity of indoor air quality issues. global review of indoor air quality in these settings norovirus gii.4 detection in environmental samples from patient rooms during nosocomial outbreaks the potential for airborne dispersal of clostridium difficile from symptomatic patients the role of particle size in pathogen 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irradiation on detection by a semi-nested rt-pcr assay detection of airborne rhinovirus and its relation to outdoor air supply in office environments in china, students in crowded dormitories with a low ventilation rate have more common colds: evidence for airborne transmission how long do nosocomial pathogens persist on inanimate surfaces? a systematic review dispersal of respiratory droplets with open vs closed oxygen delivery masks: implications for the transmission of severe acute respiratory syndrome lethal experimental infections of rhesus monkeys by aerosolized ebola virus transmission of ebola viruses: what we know and what we do not know importance of the environment in meticillin-resistant staphylococcus aureus acquisition: the case for hospital cleaning significance of airborne transmission of methicillin-resistant staphylococcus aureus in an otolaryngologyhead and neck surgery unit upper-room ultraviolet light and negative air ionization to prevent tuberculosis transmission nontuberculous mycobacterial pulmonary infections mycobacterial aerosols and respiratory disease nosocomial infections due to nontuberculous mycobacteria legionnaires' disease: a rational approach to therapy potential for aerosolization of clostridium difficile after flushing toilets: the role of toilet lids in reducing environmental contamination risk airborne infection with bacillus anthracis-from mills to mail pathogenic molds (including aspergillus species) in hospital water distribution systems: a 3-year prospective study and clinical implications for patients with hematologic malignancies indoor fungi: companions and contaminants relationship between fungal contamination of indoor air and health problems of some residents in jos release and characteristics of fungal fragments in various conditions profile and morphology of fungal aerosols characterized by field emission scanning electron microscopy (fesem) can we use indoor fungi as bioindicators of indoor air quality? historical perspectives and open questions indoor mold, toxigenic fungi, and stachybotrys chartarum: infectious disease perspective demonstration of a hermetic airborne ozone disinfection system: studies on e. coli air sanitizers-efficacy data recommendations development of methods to study the survival of airborne viruses decontamination of indoor air to reduce the risk of airborne infections: studies on survival and inactivation of airborne pathogens using an aerobiology chamber airborne assault": a new dimension in acinetobacter baumannii transmission* characterizing airborne fungal and bacterial concentrations and emission rates in six occupied children's classrooms evaporation and dispersion of respiratory droplets from coughing we thank dr john a. mitchell (wordsmith scientific and regulatory, llc, bozeman, mt) and elizabeth bruning (rb, montvale, nj) for their critical review and feedback. key: cord-305048-y42o6exe authors: sugimoto, hiroshi; kohama, takuya title: chest tube with air leaks is a potential “super spreader” of covid-19 date: 2020-06-05 journal: am j infect control doi: 10.1016/j.ajic.2020.06.001 sha: doc_id: 305048 cord_uid: y42o6exe nan the covid-19 pandemic has spread worldwide, causing more than 5.8 million infections at present (may 30, 2020). [1] infectious aerosols disperse during aerosol-generating procedures such as tracheal intubation. [2] there is a concern that aerosols may also be generated from the chest tube, especially with air leaks, even after placement. [3] we would like to share our experience. an 85-year-old man was admitted to our hospital with fever, cough, and dyspnea. chest computed tomography revealed unilateral pleural effusion and no findings of pneumonia. we performed chest tube drainage and diagnosed an acute empyema with a bronchopleural fistula causing persistent air leaks. three days later, screening rt-pcr assays for covid-19 were positive for the patient and his 5 nurses. we strictly used personal protective equipment; nevertheless, another 7 people (2 physicians and 5 nurses) associated with the patient were infected with covid-19. the outbreak of covid-19 in our hospital was thought to be related to aerosols produced by the chest tube with air leaks. for the outbreak, we could not rule out accidental hospital-acquired infection or community-acquired infection. further research is required to determine whether chest tubes with air leaks are a source of infectious aerosols. however, we clinicians should be attentive to the risk of nosocomial infection with covid-19 due to chest tubes. to prevent aerosols, closing the safety valve of a suction system is proposed. [3] it is important to note that the intrathoracic pressure will increase and tension pneumothorax may occur if the suction system is switched off with the valve closed. world health organization. coronavirus disease (covid-2019) situation reports aerosol and surface stability of sars-cov-2 as compared with sars-cov-1 covid-19: chest drains with air leak -the silent 'super spreader key: cord-317138-6nonzjbq authors: takagi, hisato; kuno, toshiki; yokoyama, yujiro; ueyama, hiroki; matsushiro, takuya; hari, yosuke; ando, tomo title: the higher temperature and ultraviolet, the lower covid-19 prevalence – meta-regression of data from large u.s. cities date: 2020-06-20 journal: am j infect control doi: 10.1016/j.ajic.2020.06.181 sha: doc_id: 317138 cord_uid: 6nonzjbq nan to the editor: higher temperature and ultraviolet (uv) index in northern europe have been reported as the most important meteorological protective factors for the transmission of influenza virus. 1 on the other hand, a recent study in china suggests that higher temperature and uv radiation may not be associated with a decrease in the epidemics of coronavirus disease 2019 (covid-19). 2 to determine whether prevalence of covid-19 is modulated by meteorological conditions, we herein conducted meta-regression of data from large u.s. cities. we selected 33 large u.s. cities with a population of >500,000 in 2010 from u.s. census bureau (http://www.census.gov). we obtained 1) integrated number of confirmed covid-19 cases in the county (to which the city belongs) on 14 may 2020 from johns hopkins coronavirus resource center (https://coronavirus.jhu.edu), 2) estimated population in 2019 in the county from u.s. census bureau, and 3) monthly meteorological conditions at the city for 4 months (from january to april 2020) from national weather service (https://www.weather.gov), world weather online (https://www.worldweatheronline.com), and global solar atlas (https://globalsolaratlas.info/map) ( table 1) . as the meteorological conditions, 1) mean temperature (f), total precipitation (inch), mean wind speed (mph), mean sky cover, and mean relative humidity (%) were available from national weather service; 2) mean pressure (mb), mean uv index, and total sun hours were obtainable from world weather online; and 3) total solar direct normal irradiation (dni) (kwh/m 2 ) in the average year was procurable from global solar atlas. monthly data for the 4 months (mean pressure/uv index and total sun hours were available for 3 months, from january to march 2020) were averaged or cumulated. the covid-19 prevalence was defined as the integrated number of covid-19 cases divided by the population. random-effects meta-regression was performed by means of openmetaanalyst (http://www.cebm.brown.edu/openmeta/index.html). in a meta-regression graph, covid-19 prevalence (plotted as logarithm transformed prevalence on the y-axis) was depicted as a function of given factors (plotted as meteorological data on the x-axis). results of the meta-regression were summarized in table 2 the present meta-regression suggests that temperature, uv index, sun hours, and solar dni may be negatively, and wind speed and sky cover may be positively associated with covid-19 prevalence. higher sun hours/solar dni and lower sky cover are probably related to higher uv radiation. despite the association of lower temperature and uv-index with the influenza transmission, 1 no association of temperature and uv radiation with the covid-19 epidemics has been reported, 2 however, which may be denied by the present results of the association of higher temperature/uv index/sun hours/solar dni and lower sky cover with lower covid-19 prevalence. in conclusion, higher temperature/uv index/sun hours/solar dni and lower wind speed/sky cover may be associated with lower covid-19 prevalence (i.e. lower temperature/uv index/sun hours/solar dni and higher wind speed/sky cover may be associated with higher covid-19 prevalence), which should be confirmed by further epidemiological researches adjusting for various risk and protective factors (in addition to meteorological conditions) of covid-19. none. low temperature and low uv indexes correlated with peaks of influenza virus activity in northern europe during no association of covid-19 transmission with temperature or uv radiation in chinese cities key: cord-253487-gl5lozn9 authors: jeanes, annette; coen, pietro g.; drey, nicolas s.; gould, dinah j. title: moving beyond hand hygiene monitoring as a marker of infection prevention performance: development of a tailored infection control continuous quality improvement tool date: 2019-07-27 journal: am j infect control doi: 10.1016/j.ajic.2019.06.014 sha: doc_id: 253487 cord_uid: gl5lozn9 background: infection control practice compliance is commonly monitored by measuring hand hygiene compliance. the limitations of this approach were recognized in 1 acute health care organization that led to the development of an infection control continuous quality improvement tool. methods: the pronovost cycle, barriers and mitigation tool, and hexagon framework were used to review the existing monitoring system and develop a quality improvement data collection tool that considered the context of care delivery. results: barriers and opportunities for improvement including ambiguity, consistency and feasibility of expectations, the environment, knowledge, and education were combined in a monitoring tool that was piloted and modified in response to feedback. local adaptations enabled staff to prioritize and monitor issues important in their own workplace. the tool replaced the previous system and was positively evaluated by auditors. challenges included ensuring staff had time to train in use of the tool, time to collect the audit, and the reporting of low scores that conflicted with a target-based performance system. conclusions: hand hygiene compliance monitoring alone misses other important aspects of infection control compliance. a continuous quality improvement tool was developed reflecting specific organizational needs that could be transferred or adapted to other organizations. preventing infection in health care settings depends on the practices and behaviors of health care workers (hcw) and organizational factors that influence practice. 1 hand hygiene has long been considered the most important infection prevention precaution, 2 and hand hygiene audit data are reported at a senior level as part of quality assurance, 3 overlooking the contribution of other important practices, for example isolation of infectious patients and sterilization and disinfection of equipment. the value of hand hygiene remains undisputed, but despite regular monitoring and performance feedback, compliance is suboptimal. 4, 5 hand hygiene forms only part of an overall infection prevention program, and its use as the overall indicator of infection prevention excellence is questionable, especially as monitoring is fraught with pitfalls. hand hygiene compliance monitoring is commonly undertaken by directly observing practice, 6 but this is flawed because hcws are aware of scrutiny and transient improvement in performance may occur, 7 generating inflated scores and not reflecting usual behavior. [8] [9] [10] a review of the hand hygiene monitoring throughout 1 organization found the data that were based on observation of practice did not accurately reflect infection control compliance, 11 contributed little to improving practice, were not considered the best use of time, and lacked local credibility. these factors are likely to influence the value of these data in practice improvement. 12 achieving and maintaining high levels of infection control compliance is challenging, 13 and few studies consider the context of care or barriers and opportunities to improve compliance. 14 recognition of the context of and constraints on practice can provide insights into the opportunities for practice improvements. the collection of related data 15, 16 includes the variability of activities, associated infection risks, and the importance of clarifying expectations of compliance. a data collection tool was required to provide credible information relating to a range of infection prevention practices, reflecting the operational risks and constraints encountered in different clinical settings and generating data of value for practice improvement. the aim of this work was to develop and implement an infection control performance and quality improvement data collection tool to meet the needs of a large, acute health care provider and to improve the credibility and use of infection control performance monitoring. the infection control continuous quality improvement (ic-cqi) tool was developed in an acute teaching hospital in london, with over 1,200 inpatient beds and 8,000 staff spread across 7 hospitals on separate sites, providing emergency, general medicine, surgery, critical care, maternity, neonatal, and cancer services. hand hygiene compliance monitoring was established, but other aspects of infection control practice were not systematically monitored. to create an ic-cqi tool and reporting framework the infection prevention team used the pronovost knowledge translation cycle 17 to review the current hand hygiene monitoring tool, and to develop a quality improvement data collection tool. the barriers and mitigation tool 18 was used to identify workplace improvement barriers and potential solutions that involved "walking the process": observing clinical processes and compliance measurement as they occurred in different clinical areas. a double loop learning cycle 19 was used to ensure that the context, values, assumptions, and culture of the whole organization were included in proposed quality improvement intervention using the hexagon tool 20 framework to assess feasibility and how to engage with stakeholders. a variety of arrangements including questionnaires, day to day contacts with auditors, feedback from users via the ic-cqi data input system, discussion groups, and ic-cqi training sessions were made for providing feedback on the data collection tool and process, to meet the operational needs, including time constraints, of different practitioners and clinical areas. modifications to the tool and implementation of the change were made in response to feedback. no other routine infection control performance data were collected apart from monthly hand hygiene compliance data collection and reporting that took place continuously across all clinical areas until this was replaced by the ic-cqi system. intermittent validation was then undertaken of ic-cqi results including hand hygiene product availability, isolation practices, appropriateness of use of personal protective equipment (ppe), and compliance with standards of invasive devices insertion and management throughout the implementation period. results are reported using the pronovost knowledge translation cycle. 17 summarize the science a literature review focused on the current evidence for opportunities and barriers to compliance in infection control, including hand hygiene that is the most researched infection control intervention, and in addition evidence from related fields such as psychology. five themes emerged that are summarized. a) knowledge, education, and training improving infection control knowledge, education, and training can enhance compliance and potentially reduce infection acquisition, [21] [22] [23] although its impact and value is disputed. 24, 25 the effect of education is difficult to gauge as it is one of a bundle of interventions in studies in which it has been judged to be beneficial. [26] [27] [28] [29] further, improvements after education may not be sustained, [30] [31] [32] and may require continuous renewal to sustain reported effectiveness, 29 although a limited ongoing residual effect has been reported. 33 the "stickiness" 34 and memorability of ideas have influenced key concepts such as the "my five moments of hand hygiene" concept 35 promoted by the world health organization, which has been widely adopted as an approach to indicate when hands should be cleaned. lack of understanding of expectations and ambiguity is a significant barrier to compliance, particularly with guidelines. 36 this is compounded by the considerable variation in the scope, approach, content, expectations, and terminology in infection control guidance and recommendations. 37, 38 improving and clarifying infection control information and expectations may improve compliance, 39 knowledge and high levels of self-efficacy are recognized to improve performance, 40 whereas poor self-efficacy, despite good theoretical knowledge, is more likely to be associated with lower compliance. 25 the promotion of infection control compliance has been used widely in acute care settings with variable outcomes, 41 and has included marketing, [42] [43] [44] campaigns, [45] [46] [47] stimulating, [48] [49] [50] and reminding staff of infection control requirements. 26, 51 motivation associated with infection control is complex and appears to be related to culture, beliefs, and values. emotion, habit/routine, and incentives affect behavior, 52 and whereas pride in work, empathy, automatic habits, and rewards may have a positive impact on compliance, sanctions could have a negative effect. 52 other factors such as the protection of patients or self [53] [54] [55] [56] or the perception of risk may also affect performance. 24, [57] [58] [59] c) environmental and human factors the health care environment influences infection control compliance 60 including equipment design, position, and workflow. [61] [62] [63] provision, availability, and accessibility of hand hygiene facilities and products are important factors in hand hygiene compliance. [64] [65] [66] [67] [68] [69] inadequate hand hygiene may be mitigated by reducing the environmental contamination of the patient environment including computer keyboards and telephones. 70 improving cleaning efficacy may reduce hand contamination. 71, 72 however, this requires an environment designed to expedite cleaning, competent cleaning staff, and sufficient time and opportunity to clean in busy clinical environments. 73, 74 other significant barriers to infection control compliance include pressure of work, understaffing, overcrowding, high bed occupancy and patient turnover, high patient-to-nurse ratio, and lack of time for education, 22, 25, [75] [76] [77] [78] which may contribute to infection transmission and outbreaks. [79] [80] [81] d) organizational priorities and culture in the united kingdom, health care organizational performance is closely monitored, and achievement of quality standards and performance targets are important. 82 health care infection acquisitions are an important marker for the quality of care delivered and organizational management. 83, 84 effective infection prevention is typically a bundle of interventions 85 including isolation provision and practice, the use of ppe, cleanliness including environment, and hand hygiene. culture, commitment, and leadership at unit or ward level affect the implementation of best practice, 12, 86, 87 whereas organizational culture can influence, improve, and sustain infection control compliance. 81, 88, 89 strong leadership, good role models, local ownership, champions, empowerment, commitment, and role have been found to be important. 86, 87, 90 e) feedback of observation of practice performance feedback is widely used to improve hand hygiene performance, 26,91-93 but has been found in other settings to be a potentially destructive process that demotivates and diminishes performance if not done well. 94 behavior changes related to observation 7 may promote "good" behavior 9 such as increasing hand hygiene compliance, 8 with more pronounced effects when observers are known to the staff. 95, 96 another benefit of observation is the opportunity to check technique, 27, 97, 98 praise, recognize constraints, or offer advice and support. clarifying and standardizing expectations prior to observation may reduce inconsistency in expectations. 99 observing sequences of care has been used as an alternative approach to simply observing hand hygiene practice. [100] [101] [102] the hcw is observed for the duration of the care activity, such as mobilizing a patient or measuring vital signs, to enable the observer to put the actions observed into the context and constraints of practice. the review of organizational data in an acute nhs trust from 2008 to 2012, established that although reported levels of compliance were high (fig 1) and met the performance target of >90% compliance, the data collection method lacked validity and relaibility. 11 nurses were responsible for data collection, and it was perceived by some as "ticking boxes" with no expectation that improvement would occur. 11 many nurses had not received training in auditing hand hygiene, no time was allocated to undertake it, and providing feedback was difficult particularly if the results were poor. 11 noncompliant staff were seldom challenged because of fear of a negative response. factors impeding compliance, such as empty soap dispensers or ambiguity of expectations, were not resolved when observed as they should have been. other issues reported by staff were inconsistent feedback about performance, inadequate facilities, dissatisfaction with products and supplies, lack of appropriate knowledge, ambiguity related to definitions, expectations and standards, and dif-ficulty in observing single rooms without causing disruption. infection control risks varied across the organization and specialties. misconceptions such as when to wear disposable gloves were not managed or monitored, and there was a focus on identifying failures in compliance, whereas good practice was unrecognized. some staff, including medical staff, were largely disengaged from the process of monitoring and improving infection control practice. the context is summarized in 6 categories of the hexagon framework that examines the current process and context of the proposed change. 20 (1) needs infection control performance data provides assurance of compliance with national standards. 103 related audits including cleaning and environmental monitoring were not collated or widely disseminated. the organization was often blind to infection control issues until a significant problem emerged. (2) fit the proposal reflected the core values of the organization. the organization supported quality improvement and this initiative created opportunities for continuous improvement based on known and locally identified opportunities and barriers. it was an organizational priority that staff were competent and regularly updated in infection prevention and control. some managers perceived that reporting low scores was an admission of failure rather than an opportunity for improvement which was a potential barrier. the potential to save time auditing aligned with an organizational strategy to reduce costs and improve efficacy. (3) resource no additional resource was required as this replaced the established data collection, reporting, and dissemination infrastructure. although it was recognized that in the existing system staff were often untrained and given no additional time to undertake this work. 11 there was potential for a decreased dependence on nurses as data collection could be shared with other team members and undertaken throughout the 24-hour period. (4) evidence there was evidence that the current system 12 lacked credibility and had little effect on improving reported compliance. 11 there was evidence of systematic defects and barriers to infection control compliance including ambiguity, disengagement, and unreliable hand hygiene product provision. issues such as isolation were increasingly problematic and required improvement, particularly with the emergence of ebola, severe acute respiratory syndrome, and middle east respiratory syndrome, when considerable resource was required to ensure staff were educated and resourced to be able to manage these emerging viruses safely. 104 (6) capacity there was capacity within the infection control department to support the changes in the data collection and reporting, training, communication, and validation of the data collected. a number of other competing changes and initiatives prevalent in the organization including building, reorganization of services, and staffing structure were potential barriers. five key themes emerged from the literature review, barriers and mitigation work, 15,16 feedback from auditors, and observations from stakeholders suggesting barriers and opportunities for improvement that were combined to produce a draft ic-cqi tool. this was pilot tested in several areas while the existing hand hygiene monitoring arrangements continued throughout the remainder of the organization (fig 2) . the draft ic-cqi tool was clarified and simplified in response to feedback. the rationale for including criteria in the final ic-cqi tool is summarized in table 1 . results of the pilot studies and the final ic-cqi tool was presented to senior managers, infection control staff, and auditors who agreed that the results would be used to provide a monthly score of infection control performance (table 2) . it took more than 3 years to develop the ic-cqi tool, educate staff in the purpose, methods, and implications for practice and integrate the data into the established quality measurement system in the organization. over 100 hours of training in the final tool was delivered across the organization, and more than 150 people attended training in 2016-2017. the use of the ic-cqi tool was finally established throughout the organization in august 2016, and the existing hand hygiene audit discontinued. all areas were expected to report using the new tool from september 2016 (fig 2) . progress developing and establishing the process is summarized in the following text. basic infection control training including hand hygiene is mandatory in the first month at work, with online updating every 2 years. initially, externally employed staff were excluded from this training and senior medical staff often opted out, but during the development of the new tool this training became mandatory for all staff. electronic training records were reported monthly to managers and the executive team. a list of common infection control questions was developed to assess the knowledge of hcws and identify education requirements. each ward or department were required to ask a representative sample of staff working in the area monthly either standard or locally developed and agreed questions. examples could include: when do you need to isolate a patient with diarrhea? describe how a spillage of blood should be cleaned up? the infection control knowledge of auditors was a limiting factor, and initially some auditors restricted questions to the ones they could answer. the range of questions and potential for improving infection control knowledge increased when answer sheets were provided. an infection control link personnel system was already established to provide local induction and refresh basic skills and knowledge in the workplace, which included hand hygiene techniques, cleaning equipment, and the use of ppe. staff turnover was high particularly in junior doctors and the burden of local induction and support was onerous in some areas. delivery varied across the organization and reflected local commitment to the induction of new team members and the energy and commitment of the link staff. it was envisaged that prompts and reminders would increase awareness and that posters and screen savers could provide useful information such as the actions to take after a needle stick injury or how to clean equipment. however, audible reminders confused some patients, irritated some staff, and were rapidly removed or sabotaged by detractors. some senior managers removed infection control notice boards as they found them "untidy," and plans to install monitors failed as there was no space or electrical supply or funds. the most enduring promotion was hand hygiene technique stickers on hand hygiene product dispensers. in addition, regular supplies of posters were delivered to wards and departments. local managers were responsible for arranging maintenance, but the process could be onerous and protracted. metrics relating to minor repairs were not collated and recurring problems were largely invisible. an issue mentioned frequently was empty or broken soap and alcohol hand gel dispensers. organization-wide audits in 2013 found 18% of soap dispensers were broken or empty and there were examples of delays of several days before they were repaired. in 2013-2014, a project was undertaken to replace all soap and alcohol hand gel dispensers with standardized products and dispensers that staff had positively evaluated. the condition of soap and gel dispensers was subsequently included in the ic-cqi tool, and subsequent validated scores indicated a sustained improvement across the organization. the range of specialties, workflows, client groups, facilities, and infection risks provided a wide variety of area-specific issues that emerged from staff observations, audits, feedback, complaints, and root cause analysis. these included correcting air pressure in isolation rooms, staff refusing to remove wrist watches, parents visiting neonates while contagious, inappropriate disposable glove use, and poor patient hand hygiene. staff identified local issues requiring improvement and agreed on expectations and actions. these were included in the daily handover, local education, knowledge assessment, and the progress audited. once improvement was demonstrated, monitoring could stop and switch to other issues of concern. is there alcohol gel at each bed end that is filled and working? are soap and hand towel dispensers filled, clean, and working at each sink? are the alcohol gel dispensers at entrance and wall-mounted dispensers filled and working? check tapsâ��are they correctly adjusted for elbow operation? is gel available on desks, next to keyboards, and by notes trolleys? check keyboardsâ��are they being cleaned regularly? area specific criteria examples include: are patients provided with hand wipes at mealtimes? is the environment clean and cleaned to a high standard? is glove use appropriate? observation single room/sequence of care observation. some areas readily used this opportunity to identify, improve, and monitor issues, whereas others were reluctant to highlight problems as there was anxiety about producing a low score even for a short period. sometimes, encouragement was required to tackle an area of practice that was recognized as requiring improvement. e. observation of single room practice and sequences of care feedback indicated that observing practice was valued by staff as an opportunity to look at practice delivery and the environment. there was also a recognition that staff disliked covert observation and wanted to understand what was expected and how they could improve practice. two types of observation: observing sequences of care and single room isolation practice were identified in pilots as potentially useful and acceptable to hcws and were subsequently adopted. both required training auditors and clarification and agreement of expectations with practitioners and subsequent inclusion in local education. sequence of care monitoring requires the observer to compare the infection control expectation with performance, records, data, and offers an opportunity to provide feedback. examples include observing doctors on a ward round or a nurse preparing and administering intravenous drugs. sometimes, it was difficult to understand what was monitored as documentation was often limited and it was not always possible to validate these observations. single room observation monitored isolation practice using an audit tool. an observer records the infection control practice expectations, and then while positioned outside the room, observes, records, and offers feedback of performance. this may include infection control precautions taken by people entering and leaving the room, if the isolation sign was accurate, and if adequate ppe was available. these data were simple to validate, and the tool was also used to check isolation practice compliance ad hoc to clarify expectations of new patients requiring isolation. the ic-cqi tool ( table 2 ) was evaluated to assess acceptability to local auditors and managers 105 and if the results were perceived to be a fair reflection of performance. 12 at this stage, the assessment focused on the perspective of the auditors and those using the information rather than those being assessed. in december 2016, 27% (6 of 22) of data collectors responding to online questionnaires had time allocated to undertake data collection. this had increased to 55% (27 of 49) by june 2017. those trained in the use of the tool had also increased slightly from 44% (23 of 52) in 2013 to 48% (24 of 50) in 2017. use of the tool had increased to 100% (50 of 50 wards sampled) in 2017, and 64% (32 of 50) believed the tool had helped improve infection control practice in their area. a total of 70% (35) did not believe the tool had led to a decline in infection control practice standards, and 59% (29 of 49) believed the data were an accurate reflection of practice. in addition, auditors assessed observation, knowledge, education, and promotion of awareness as the most valuable components of the tool, while at the same time the most difficult to collect (fig 3) . data collectors/auditors consistently requested more training in the use of the tool, more prepared questions rather than locally developed questions, and simplification of the data collection process. validation of the scores obtained were undertaken by the infection control team, although some observations were difficult to validate particularly in the presence of local interpretations. 12 the use of the tool and validity of the data collected continue to be evaluated. infection reduction data are not reported here as it is unlikely that outcomes will be directly attributable to the use of the tool as other improvements and changes in care occur frequently such as increased isolation provision and increases in robotic surgery. broadening the scope of monitoring to include other aspects of infection control practice beyond hand hygiene was hampered by a lack of a robust evidence base for some common infection control practices 106 and inconsistent opinions from subject matter experts. 36 this created some ambiguity of expectations of infection control practice, but consensus was often achieved when the rationale for practice was examined and options explored. the approach was sometimes uncomfortable for senior infection control staff but liberating for junior staff who were empowered to question entrenched habitual practice. 107 changes in the focus of monitoring considered the value of knowledge, education, training, and human factors and were readily accepted, but, despite evidence that local ownership and participation is beneficial, 108 this was difficult to achieve. staff were seldom allocated time to attend training or collect information and sometimes lost the momentum to identify new areas for local improvement. lack of energy and resilience has been recognized previously in nhs staff, and it has been suggested that this may be related to an underlying lack of engagement and absence of positive reinforcement for previous efforts. 109 these issues were particularly problematic when there was potential for reporting lower scores conflicting with the established organizational aspiration 110 of reporting high performance. resistance to acknowledging and monitoring areas that required improvement was a recurring issue during the development and implementation of this tool. although the fallibility of the previous monitoring system was recognized within the organization, the use of soft intelligence provided by local observations and feedback 111 was a major departure from the normal practice of collecting data for assurance to one of improving practice. 112 consequently, the assimilation of this change within the organization was slow, 113 and auditors reported persistent pressure from managers to achieve targets and avoid highlighting areas for improvement. at times this perpetuated the organizational blindness to problems and it was unclear if this influenced the priority given for time for training and data collection. establishing rational and feasible expectations of hcws within the context of care delivery and providing information including data that was useful locally had a positive impact on engagement and acceptance of the changes introduced. 12 however, the flexibility and adaptability of the tool created inconsistencies and anomalies that hampered standardization of practice and validation of results. the use of observation of practice was valued by auditors but standardization of practice was simpler to achieve and validate when an unambiguous audit tool was provided, for example, the single room audit tool as this was less reliant of staff knowledge and local variations. a widely used hand hygiene compliance monitoring system produced data that did not contribute to quality and safety improvement in 1 organization, and an alternative quality improvement tool was developed and implemented. consideration of the context of care delivery led to the creation of a flexible and pragmatic tool that could be adapted. the previous focus on hand hygiene compliance was replaced by monitoring performance in a range of infection controlrelated factors. this work was undertaken in 1 organization that may limit generalizability. the barriers and opportunities identified may vary in other organizations and facilities that may affect replication, 114, 115 although issues such as ambiguity, poor role models, and knowledge are likely to be common. the tool is now established as a performance metric in the organization and has been adopted and adapted in other health care organizations. 105 the removal of ambiguity, realistic expectations, and local engagement contributed to the successful introduction and continued use of this tool. further 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report improving nhs care by engaging staff and devolving decision-making: report of the review of staff engagement and empowerment in the nhs employee engagement within the nhs: a crosssectional study evaluating the evidence on employee engagement and its potential benefits to nhs staff: a narrative synthesis of the literature beyond metrics? utilizing 'soft intelligence' for healthcare quality and safety the three faces of performance measurement: improvement, accountability, and research diffusion of innovations in service organizations: systematic review and recommendations using research to inform healthcare managers' and policy makers' questions: from summative to interpretive synthesis explaining michigan: developing an ex post theory of a quality improvement program. milbank q key: cord-316442-xwopn97m authors: lam, simon ching; suen, lorna kwai ping; cheung, teris cheuk chi title: global risk to the community and clinical setting: flocking of fake masks and protective gears during the covid-19 pandemic date: 2020-05-13 journal: am j infect control doi: 10.1016/j.ajic.2020.05.008 sha: doc_id: 316442 cord_uid: xwopn97m nan the 2019 coronavirus disease (abbreviated covid-19) was believed to be originated in wuhan, china in late december, 2019. this disease is rapidly transmitting to more than 200 countries, and has become a pandemic. geographically, hong kong is located proximally to wuhan-the epicenter. with the rapid transmission of the covid-19, hong kong has been confronted by the increasing number of confirmed and suspected cases daily, now exceeding 1,000 at the time of reporting. hong kong people are beyond doubt in a state of anxiety, fear and helplessness. the latest evidence indicates that face mask helps prevent the transmission of human coronaviruses and influenza viruses from symptomatic individuals [1] and thus, an increasing number of healthcare authorities have recommended the use of face mask in public spheres for self-protection and others [1] [2] [3] . consequently, hong kong people started a mass surge of surgical masks locally and nationally. this gives a golden opportunity to thousands of fake masks and protective gears flocking in markets ever since the pandemic [4, 5] . however, there is rare empirical data to unfold this condition regarding severity and prevalence. in accordance with astm f2299-03 international standard [6], our squina international centre for infection control established a system to estimate the particle filtration efficiency (pfe) of face mask. this estimation was performed to evaluate the pfe of a given face mask by comparing the artificial generated aerosols in upstream (i.e., outside mask) of the test article with the downstream (inside mask). the aerosols were generated by sodium chloride and kept in the buffer chamber until reaching an optimum test environment, including aerosol concentration between 10 7 and 10 8 particles/m 3 , humidity of 30-50% (+ 5%), and temperature of 21°c (+ 3°c). two sets of optical particle counter (grimm aerosol spectrometer, model 1.109) [7] were used to capture and count the aerosols with the size of 0.3 µm and 1 µm at upstream and downstream. five to ten pairs of consistent data (<3% variation of particle count) were used to estimate the pfe. this system was validated with automated filter tester (tsi model 8130a as gold standard for 0.3 μm pfe) [8] by comparing the known 0.3 μm pfe materials from 40.33% to 99.99%. results indicated that the pfe difference ranged from -6.81% to 3.85% (mean = -1.65, sd 3.47). concurrent validity that correlated the two set of pfe scores was also satisfactory (r = 0.99, p < 0.001). we tested 160 brands of masks from different sources and countries (figure 1) . results showed that low-quality face masks accounted for 48.8% (i.e., 0.3 μm pfe, mean = 47%; 1 μm pfe, mean = 69%). approximately 42.6% of face masks claimed to achieve astm level 1 standard (i.e., pfe > 95% on 0.1 μm, provided with certification or printed description on box) but demonstrated insufficient filtration performance at 0.3 μm (range = 6%-94%). surprisingly, we extracted seven considerably from 38% (fake ones) to 99% (good-quality ones). counterfeit and fake face masks are merely the tip of the iceberg in the personal protective equipment market [9] . however, general public and even healthcare professionals may be unable to distinguish the counterfeit and fake face masks from those quality one. more importantly, most organisations and hospitals nationwide lack the appropriate equipment to initially examine the purchased face masks prior to distribution to different units. it is anticipated that they may face similar difficulty in examining their ppes, n95 respirators, and surgical gown. our test results were alarming because using fake masks / protective gears will jeopardize the health of covid-19 patients, suspected cases, close contacts, and vulnerable subpopulation (health professionals, older adults, patients with chronic disease, poverty). illegal fake mask and protective gears manufacturing may disrupt the infection prevention and control towards the covid-19 outbreak in clinical and community settings. failure to curb the rapid disease transmission may transform the infectious pandemic into a new hybrid disaster (natural and man-made events). thus, there is a pressing need for the food and drugs authority (fda) to impose stringent guidelines on proper face mask production, materials to be used, quality control, commodity labelling, distribution and recommended price range. local and international governing bodies should strictly enact and enforce legal guidelines to forbid fake mask/ protective gears manufacturing with a serious penalty to deter those profiteers. the local government should educate the general public to distinguish between good quality masks with those fake face masks via social media. vulnerable subpopulation should also have heightened awareness to counterfeit / face masks to avoid falling into the profiteers' net. funding source: we declare no competing interests. respiratory virus shedding in exhaled breath and efficacy of face masks mass masking in the covid-19 epidemic: people need guidance total disregarded for people's lives': hundreds of thousands of fake masks flooding markets as coronavirus depletes world supplies sourcing personal protective equipment during the covid-19 pandemic standard test method for determining the initial efficiency of materials used in medical face masks to penetration by particulates using latex spheres comparing mask fit and usability of traditional and nanofibre n95 filtering facepiece respirators before and after nursing procedures testing for air filters and filter media counterfeit filtering facepiece respirators are posing an additional risk to healthcare workers during covid-19 pandemic figure 1 we thank the organizations who provided the different face masks for this study. we thank dr. si san kwong for validating the system by the tsi; ms. shun chan and ms.francisca wing ka so for their assistance in the data collection. key: cord-313409-3n4vyszl authors: hines, stella e.; oliver, marc s.; gucer, patricia; mcdiarmid, melissa a. title: self-reported impact of respirator use on healthcare worker ability to perform patient care date: 2020-06-11 journal: am j infect control doi: 10.1016/j.ajic.2020.06.005 sha: doc_id: 313409 cord_uid: 3n4vyszl in a study of 1152 healthcare workers surveyed prior to the covid-19 pandemic, most disagreed that respiratory protective equipment use interferes with patient care but reported that it would affect respirator use compliance if it did. a patient's fear reaction variably influenced self-reported healthcare worker compliance with respirator use. strategies to improve protective equipment design may remove potential barriers to respirator use and allow better healthcare worker-patient relationships. in a study of 1152 healthcare workers surveyed prior to the covid-19 pandemic, most disagreed that respiratory protective equipment use interferes with patient care but reported that it would affect respirator use compliance if it did. a patient's fear reaction variably influenced self-reported healthcare worker compliance with respirator use. strategies to improve protective equipment design may remove potential barriers to respirator use and allow better healthcare worker-patient relationships. key words: respirators, personal protective equipment, patient interaction, facial mask, interference human factors associated with respirator use have long been a topic of concern, from comfort, communication, heat tolerance and impact on care, including relationships with patients (1-7). hcws have stated that they may avoid patients when ppe use is required and that patients feel uneasy when respirators are required (5) . earlier literature showed that while hcw mask use did not impact patient satisfaction, it did reduce perceptions of hcw empathy (4). in the setting of widespread mask use for patient care during coronavirus disease 2019 (covid-19), findings from a previous assessment of hcw opinions on this topic during non-pandemic use were explored. hcws enrolled in a medical system's respiratory protection program (rpp) were queried both during a focus group interview of eleven hospital staff members and a larger medical system-wide electronic survey of 1152 hcws regarding their perceptions and beliefs about the impact of respirators on their ability to provide patient care (8) (9) . during a focus group interview in 2015, hcws were asked to describe how use of respirators impacted their ability to provide care and whether patients or their family members interact differently with them when they are wearing respirators. the interview was recorded, transcribed, and iteratively reviewed by four researchers for key themes, facilitated by use of nvivo 10 software (8) . in a subsequent electronic survey, hcws in rpps in a medical system with approximately 9600 respirator users were queried in the fall of 2016. eligibility to participate included age ≥ 18 years, employment with current employer ≥ three months, and having worn a respirator at least once within the previous year. settings included a large us academic urban hospital and four affiliated community hospitals or ambulatory practice. participants were recruited via email invitations and in-unit visits by the study team and received gift cards limited by the study budget to the first 1152 respondents. the study was approved by the local institutional review board. survey frequencies were calculated for demographic characteristics and four questions related to perceived respirator impact on patient care, the latter asked as five category likert-style scales. two questions addressing impact on compliance were prefaced with the statement: "consider a situation in which you must enter the room of a patient who is on airborne precautions, where there is high suspicion for active tuberculosis. how are important are the following factors in regard to your compliance with wearing your respirator?" for presentation here, responses were combined to make three categories. both "strongly agree" and "agree" and "strongly disagree" and "disagree" were combined. chi-square analysis was performed to evaluate participant response across respirator user groups. focus group participants reported that while patients or families often initially have questions about respirator use, these questions typically subside after an understanding of why the mask is necessary. hcws recognized that while mask use did not create conflict with patients or family members, it limited the ability to be seen smiling, and they speculated that a transparent mask might be better. survey participants were predominantly female nurses from a large academic medical center and users of n95 respirators (table 1) . most respondents did not find that use of respirators and ppe impacted their ability to perform patient care (62%) or that it was inconvenient (51%) ( table 2 ). most reported that if respirator use interfered with their ability to perform care, it would influence their compliance with respirator use. participant responses were evenly distributed regarding whether patients' fearful reactions toward caregiver respirator use would impact compliance with their use. among the minority of respondents who did find that respirators interfered with patient care, responses differed by user groups (p<0.05 for overall comparison). more papr users (27%) than n95 (17%) and elastomeric (16%) users agreed that respirator use interferes with patient care. this pattern was not directly related to low frequency of use, as use 1% of the time or less was similar in papr (55%) and n95 users (54%), compared to 44% of elastomeric users (3). while more nurses (22%) and providers (28%) agreed that use of respiratory protection interferes with patient care, only 9% of respiratory therapists and 10% of patient support staff also agreed. this survey, performed prior to the covid-19 pandemic, suggests that any interference with patient care caused by ppe use would influence hcw compliance with its use. fortunately, here, most hcws reported that ppe use did not interfere with patient care and was not inconvenient. this may reflect a willingness of hcws to use protective equipment that may be cumbersome or uncomfortable, when the tradeoff is protection of their own health. for example, previous research found that elastomeric respirator users, who rated the respirators less favorably with respect to comfort, but higher in perceived level of protection, still preferred to use them in certain higher risk scenarios, such as during pandemic influenza (9) . acceptance of less convenient but more protective safeguards may be more pronounced among hcws while providing care to covid-19 patients. this report reflects responses of hcws during general care provision. it does not address ppe interference with specific tasks or induced by combinations of ppe, such as ensembles including face shields, gowns and head covers. thus, there may be limitations in applying these broad findings about respiratory protective equipment to specific care scenarios. additionally, during crisis times when ppe use may be prolonged, hcw perceptions may differ from when assessed under routine scenarios. changes in ppe design to allow visible facial expression, decreased mask size and better voice transmission might alleviate many existing challenges to the caregiverpatient relationship and to enhance its utility in clinical settings (6) . additionally, enhanced hcw training and patient and family education on the necessity for mask use may foster better therapeutic alliance between patients and their hcw clinical providers. b95: a new respirator for health care personnel effect of facemasks on empathy and continuity: a randomized controlled trial in primary care health care workers' reported discomfort while wearing filtering face-piece respirators the use and effectiveness of powered air purifying respirators in health care: workshop summary a tolerability assessment of new respiratory protective devices developed for health care personnel: a randomized simulated clinical study qualitative analysis of origins and evolution of an elastomeric respirator-based hospital respiratory protection program user acceptance of reusable respirators in health care table 1 -demographic characteristics of healthcare worker respirator users completing survey key: cord-285849-jg43tcfh authors: chan, ben chong pun; lee, chin peng; tang, grace wai king title: universal sars preventive measures in an obstetrics unit: experience of health care staff date: 2004-10-30 journal: am j infect control doi: 10.1016/j.ajic.2004.01.006 sha: doc_id: 285849 cord_uid: jg43tcfh background: severe acute respiratory syndrome (sars) epidemics have affected populations in many countries, including hong kong. this disease is infectious, especially in hospital settings. health care workers have expressed great concern, including those working in obstetrics wards, defined as high-risk areas. method: four weeks after implementation of universal precautionary measures at a teaching hospital in hong kong, a survey of the health care staff was conducted to identify their feelings and opinions. results: in spite of general knowledge about sars epidemics and related mortality, most respondents stated that universal precautionary measures were not very necessary, especially in the obstetrics ward. in addition, respondents were generally dissatisfied with the measures, as most items imposed extra work, inconvenience, and burdens on the staff. conclusion: our findings reported the views and satisfaction levels of the front-line staff of an obstetric unit concerning precautionary measures against sars. the importance of individualized design and implementation of infection control measures is highlighted and discussed. severe acute respiratory syndrome (sars) epidemics affect populations in many countries, in both hospital and community settings. caused by coronavirus and spread by droplet transmission, 1-5 this disease and its high mortality rate have increased the psychological stress of all health care staff. 4 various precautionary measures have been suggested. universal precautionary measures were believed to be necessary, especially in certain high-risk areas such as obstetrics wards, where contact with body fluid is common. health care workers demanded personal protective equipment (ppe). the labor ward and obstetrics operating theater of queen mary hospital, which is a tertiary center, adopted universal precautions in may 2003. previously, only surgical gowning, single gloving, paper cap, surgical face mask, and boots were worn in the delivery room. since early may 2003, universal precautionary measures were implemented and changes in ppe are shown in table 1 . understandably, such measures would impose extra work, inconvenience, and burdens to the staff, and might hinder the effective and efficient execution of their work. a simple questionnaire survey was conducted 4 weeks after the implementation of the universal precautionary measures. our objectives are to present the views of our front-line staff, and to discuss universal precaution measures in obstetrics. an anonymous survey comprised of 5-point, likertscale items was conducted in early june 2003. medical staff (obstetricians), nursing staff, medical students, and supporting staff working in the labor ward and the obstetrics operating theater were asked about the necessity for and their satisfaction with each of the universal precautionary measures. statistical analysis was carried out with spss for pcs, version 11.5 (spss inc, chicago, ill). bivariate correlation procedures and one-way analysis of variance tests were used, with statistical significance defined as p < 0.05. a total of 109 questionnaires were distributed 4 weeks after implementation of universal precautionary measures. ninety-six questionnaires were returned (88%). the demographic characteristics of the respondents are shown in table 2 . the respondents' opinions are summarized in figs 1 and 2. most staff were quite neutral toward the necessity of the preventive measures in labor ward. on the other hand, they indicated that these measures are more necessary in the operating theater. goggles and double gloving were perceived as the most necessary ppe items. most staff were neutral or even unhappy about the precautionary measures. in particular, goggles were the least-welcome item, although they were believed to be necessary. relationships between various demographic factors and the overall assessment rating were also investigated. the only statistically significant differences found pertained to occupation (p = 0.001) and gender (p = 0.034) regarding the necessity of the overall arrangement of universal precautions. support staff and midwives found such preventive measures more necessary, and obstetricians found them much less necessary. women held a more positive perception concerning the necessity of these measures. these results are congruent, as all midwives and most support staff in our unit are women. ratings on the necessity of ppe were unexpectedly the lowest among the medical staff who should be in the closest contact with women in delivery. on the other hand, the support staff who clean the rooms believed that universal precautions were necessary. a number of explanations could be offered for this difference. first, our clinical staff may have been subconsciously assured that contact with sars patients in the obstetric unit would be most unlikely, since obstetrics patients are mostly afebrile without any respiratory symptoms. the support staff does not have this knowledge. second, the ppe hindered the efficient care of pregnant women. goggles, eye shields, and multilayered protective clothing distort visual acuity and induce intense perspiration in the medical/nursing staff who had to be with women in labor for many hours. in contrast, the support staff only had to wear the ppe when they cleaned a room, which usually took less than 15 minutes. visual distortion and heat generated by the ppe then would not be as problematic for support staff, who stated that they felt they were being protected more than peers on other wards. third, medical/nursing staff were already accustomed to some form of protective clothing during their daily activities in the ward and operating theater. they might already feel protected from contamination by patients. additional ppe might then be considered superfluous, depending on the area they worked in and their specific duties. satisfaction levels with ppe were lower among labor ward staff than among operating theater staff, who were more accustomed to full infection protection. the occupational specialty mindset was very important, not only in terms of satisfaction with universal precautions, but also effective implementation. it is worthwhile noting that there were some discrepancies between perceived need and satisfaction with individual protective equipment. this discrepancy seems to be related to the comfort of the equipment. goggles were deemed to be needed, but they were tight, foggy, and reduced visual acuity; hence, the low satisfaction rate. paper hoods are comfortable, and hence respondents indicated a high satisfaction rate, but were not rated as highly necessary since head hair were not considered to be a transmission site. gloving, gowning, and footwear were more consistent in levels of need and satisfaction. these have been the usual ppe that staff are accustomed to. this was a small study that aimed at appraising the effects on staff of universal precautions against sars. it was not meant to produce figures reaching high levels of statistical power. our findings should be important for health care managers to reassess the concept of universal precaution, and where and how it should be instituted. unless this is done, universal precautions will not be implemented effectively, staff will not be protected, and managers will have a false sense of security. sars is an elusive and frightening infectious disease. it is obvious that there is an immense need for protection of all health care workers, including support staff. our experience of universal precautionary measures in an obstetrics unit may start the discussion on the best precautions for particular health care staff in specific work environments. perceived need and satisfaction, obstetrics operating theater staff (score with 95% confidence interval). coronavirus as a possible cause of severe acute respiratory syndrome effectiveness of precautions against droplets and contact in prevention of nosocomial transmission of severe acute respiratory syndrome (sars) transmission dynamics of the etiological agent of sars in hong kong: impact of public health interventions the immediate psychological and occupational impact of the 2003 sars outbreak in a teaching hospital identification and containment of an outbreak of sars in a community hospital key: cord-300754-q356npb7 authors: choi, hye-suk; kim, mi-na; sung, heungsup; lee, jeong-young; park, hee-youn; kwak, sun-hee; lim, young-ju; hong, min-jee; kim, sun-kyung; park, so-yeon; kim, hyeon-jeong; kim, kyu-ri; choi, hye-ran; jeong, jae sim; choi, sang-ho title: laboratory-based surveillance of hospital-acquired respiratory virus infection in a tertiary care hospital date: 2017-05-01 journal: am j infect control doi: 10.1016/j.ajic.2017.01.009 sha: doc_id: 300754 cord_uid: q356npb7 of 7,772 laboratory-confirmed cases of respiratory viral infection among hospitalized patients, 22.8% were categorized as having hospital-acquired infection. the overall incidence of hospital-acquired respiratory viral infection was 3.9 (95% confidence interval, 3.7-4.1) cases per 1,000 admitted patients. rhinovirus was the most common virus (30.3%), followed by influenza virus (17.6%) and parainfluenza virus (15.6%). the human respiratory viruses include adenovirus, bocavirus, human coronaviruses, enterovirus, influenza viruses, human metapneumovirus, parainfluenza virus, respiratory syncytial virus, and rhinovirus. although respiratory viruses are mainly recognized as causes of community-acquired infections, they can also cause serious hospital-acquired respiratory infections 1 and may be responsible for hospital outbreaks. [2] [3] [4] their relatively short incubation times and efficient transmission via small droplets among comorbid patients highlight the need for better understanding of respiratory viral infections in hospital settings. however, very limited published data are available on the overall epidemiologic characteristics of hospital-acquired infection caused by respiratory viruses, especially by viruses other than influenza viruses. therefore, using laboratory-based surveillance, we investigated the overall incidence and related factors of hospital-acquired respiratory virus infections. this study was performed at a 2,700-bed, tertiary care, universityaffiliated hospital between january 2012 and december 2015. all admitted patients who had positive test results for respiratory virus polymerase chain reaction (pcr) were prospectively identified and monitored until their discharge or release from isolation. performance of the pcr test for respiratory viruses was at the discretion of the attending physician. outpatients and patients discharged in the emergency room were not included. respiratory viruses were detected by multiplex reverse-transcription pcr assay using a seeplex rv15 ace detection kit (seegene, seoul, korea) (january 2012-october 2013) or anyplex ii rv16 detection kit (seegene) (november 2013-december 2015). the performance of those pcr kits used in this study has been evaluated in a published study. 5 6, 7 the proportion of hospital-acquired respiratory viral infections was calculated for all viruses. the incidence of such infections was calculated as the number of cases per 1,000 admissions and as cases per 10,000 patient days. this study was approved by the institutional review board of asan medical center. during the study period, there were 453,075 admissions, and a total of 21,288 respiratory viral pcr tests were conducted. table 1 shows the variation of the number of study subjects from year to year. a total of 7,772 nonduplicative pcr-positive cases were identified. of these, 1,770 (22.8%) were categorized as having hospital-acquired infections. a total of 1,888 viruses were identified: 2 viruses were identified in 101 patients, 3 viruses were identified in 7 patients, and 4 viruses were identified in 1 patient. of the 1,888 viruses identified, 573 (30.3%) were positive for rhinovirus, 333 (17.6%) were positive for influenza virus comprising 254 with influenza a and 79 with influenza b, 294 (15.6%) were positive for parainfluenza virus, 240 (12.7%) were positive for respiratory syncytial virus, 230 (12.2%) were positive for human coronavirus, 91 (4.8%) were positive for human metapneumovirus, 54 (2.9%) were positive for bocavirus, 43 (2.3%) were positive for adenovirus, and 30 (1.6%) were positive for enterovirus. the proportion of hospital-acquired infections was highest in human coronavirus (30.2%), followed by parainfluenza virus (29.8%), influenza virus (28.1%), rhinovirus (24.5%), respiratory syncytial virus (21.4%), bocavirus (21.1%), human metapneumovirus (20.5%), entero-virus (14.0%), and adenovirus (9.1%). the median length of hospital stay prior to contracting a respiratory viral infection was 16 days (interquartile range, 9-32 days). the overall incidence of hospital-acquired respiratory virus infections was 3.9 cases per 1,000 admissions (95% confidence interval, 3.7-4.1) and 4.9 cases per 10,000 patient days (95% confidence interval, 4.7-5.2). the incidences of such infections according to the year, sex, age group, ward, and virus type are summarized in table 1 . the incidences ranged from 3.6-4.3 cases per 1,000 admissions, with the highest incidence in the year 2015. patients ≤15 years were more likely to develop hospital-acquired respiratory virus infections. the incidence of such infections was highest in intensive care units (icus), followed by medical wards and surgical wards. of the icu cases, the median days of icu stay before viral infection was 4 days (interquartile range, 1-12). all-cause 30-day mortality, 60-day mortality, and in-hospital mortality were 11.3%, 16.5%, and 12.9%, respectively. the seasonal distribution of hospital-acquired respiratory viruses among hospitalized patients was similar to that of communityacquired infections (supplementary fig s1) . we found that hospital-acquired respiratory viral infections commonly occurred in a tertiary care hospital. despite the inherent limitations of laboratory-based surveillance, which underestimated the disease burden, >20% of respiratory viral infections of hospitalized patients were categorized as hospital-acquired events, and various respiratory viruses were responsible. our study is notable in that we included year-round data from 4 consecutive years and provided the admission days-adjusted incidence for each infection. data on hospital-acquired respiratory virus infections are still very scarce, mostly confined to influenza virus infections. a canadian group reported that among hospitalized patients in 51 canadian hospitals, 23.2%-23.6% of influenza virus infections were health careassociated infections. 8 a german group recently reported the proportion of hospital-acquired influenza virus infection as 20.5%-24.6%. 9 our rate of such infections (28.1%) was somewhat higher than prior reports. our inclusion of pediatric patients may have been responsible for this. of note, the influenza virus was responsible for only 13.9% of all hospital-acquired respiratory viral infections. that is, most cases were caused by respiratory viruses other than the influenza virus and which have received much less attention. these findings highlight the importance of year-round surveillance and infection control measures for various respiratory viruses beyond the influenza virus. according to our results, the incidence of hospital-acquired respiratory virus infections has increased in recent years. we speculate that increased numbers of prescriptions for pcr tests for hospitalized patients are responsible for this finding. that means that clinicians are increasingly aware of respiratory viral infection as one of the important causes of hospital-acquired infection. the use of more sensitive pcr kits in recent years may also have affected the incidence of respiratory viral infection. however, because the reported sensitivities of the 2 assays (93.3% and 95.2%, respectively) are similar, 5 the impact of changes in the pcr kits is not likely to have been substantial. surprisingly, the incidence of respiratory virus infections was highest in icus. considering the brevity of icu stays (median, 4 days) before the detection of viruses, it is probable that most of the cases were hospital-acquired lower respiratory tract infections that occurred in wards, not in the icus. these findings are consistent with those of a spanish group, which showed that during the influenza season, 29.5% of critical patients with suspected lower respiratory tract infections had influenza, 42% of which were hospital acquired. 10 it has also been reported that respiratory viruses were responsible for 22.5% of cases of severe hospital-acquired pneumonia requiring icu admission in adults. 11 these results strongly suggest that hospital-acquired infections caused by respiratory viruses could lead to serious consequences. this study had several limitations. first, it was performed at a single, large tertiary care hospital. our study population included a substantial number of immunocompromised patients who were susceptible to infection, which likely biased our results. second, some patients categorized as having hospital-acquired infections may have been already carrying respiratory viruses at the time of admission. finally, the indications for conducting pcr tests for respiratory viruses were not standardized across the hospital, and the detailed significance of pcr-positive cases was not analyzed. in conclusion, hospital-acquired respiratory viral infections are commonly encountered among hospitalized patients. hospital surveillance of respiratory viruses should be considered to identify infected patients early and to prevent intrahospital transmission of respiratory viruses. nosocomial spread of viral disease respiratory syncytial virus infections on an adult medical ward outbreak of human parainfluenza virus 3 infections in a hematopoietic stem cell transplant population possible role of aerosol transmission in a hospital outbreak of influenza comparison of anyplex ii rv16 with the xtag respiratory viral panel and seeplex rv15 for detection of respiratory viruses red book: 2015 report of the committee on infectious diseases case definitions for national notifiable infectious diseases. osong: kcdc understanding the burden of influenza infection among adults in canadian hospitals: a comparison of the 2009-2010 pandemic season with the prepandemic and postpandemic seasons characterisation of nosocomial and community-acquired influenza in a large university hospital during two consecutive influenza seasons should lower respiratory tract secretions from intensive care patients be systematically screened for influenza virus during the influenza season viral infection is not uncommon in adult patients with severe hospital-acquired pneumonia supplementary data related to this article can be found at http://dx.doi.org/10.1016/j.ajic.2017.01.009. key: cord-306930-tuositq1 authors: kwok, yen lee angela; gralton, jan; mclaws, mary-louise title: face touching: a frequent habit that has implications for hand hygiene date: 2015-02-01 journal: am j infect control doi: 10.1016/j.ajic.2014.10.015 sha: doc_id: 306930 cord_uid: tuositq1 background: there is limited literature on the frequency of face-touching behavior as a potential vector for the self-inoculation and transmission of staphylococcus aureus and other common respiratory infections. methods: a behavioral observation study was undertaken involving medical students at the university of new south wales. their face-touching behavior was observed via videotape recording. using standardized scoring sheets, the frequency of hand-to-face contacts with mucosal or nonmucosal areas was tallied and analyzed. results: on average, each of the 26 observed students touched their face 23 times per hour. of all face touches, 44% (1,024/2,346) involved contact with a mucous membrane, whereas 56% (1,322/2,346) of contacts involved nonmucosal areas. of mucous membrane touches observed, 36% (372) involved the mouth, 31% (318) involved the nose, 27% (273) involved the eyes, and 6% (61) were a combination of these regions. conclusion: increasing medical students' awareness of their habituated face-touching behavior and improving their understanding of self-inoculation as a route of transmission may help to improve hand hygiene compliance. hand hygiene programs aiming to improve compliance with before and after patient contact should include a message that mouth and nose touching is a common practice. hand hygiene is therefore an essential and inexpensive preventive method to break the colonization and transmission cycle associated with self-inoculation. infections may be transmitted by self-inoculation. self-inoculation is a type of contact transmission where a person's contaminated hands makes subsequent contact with other body sites on oneself and introduces contaminated material to those sites. 1, 2 although the literature on the mechanisms of self-inoculation of common respiratory infections (eg, influenza, coronavirus) is limited, [3] [4] [5] contaminated hands have been reported as having potential to disseminate respiratory infections. 6 staphylococcus aureus is carried in the nasal mucosa in approximately 25% of the community 7, 8 and, may be self-inoculated, via face touching, by individuals who are frequently exposed to potential carriers in both the community and health care settings. 9, 10 during the influenza a (h1n1) pandemic, face-touching behavior in the community was commonly observed with individuals touching their faces on average 3.3 times per hour. 11 in the health care setting, frequent face touching, particularly during periods of seasonal endemicity or outbreak, has the theoretical potential to be a mechanism of acquisition and transmission. 1 however, quantifying the role of face touching in the spread of respiratory infections or s aureus colonization is difficult for several reasons. first, such a study would require enrollment, screening, and prospective follow-up of a large population to identify a significant causal link. second, the study would need to observe transmission occurring in community settings, rather than in isolation or under laboratory conditions, which would be ethically challenging. finally, there are likely to be confounding factors, such as virulence of pathogens, varying susceptibility of the study population, and effects of modes of transmission other than hand to face contamination, that cannot easily be controlled. a self-inoculation event may occur if a health care worker (hcw) fails to comply with hand hygiene after patient contact (moment 4) 12 or after contact with the contaminated environment of the patient's zone (moment 5) (fig 1) and makes subsequent physical contact with susceptible sites on their own bodies. to better understand the dynamic between face touching and the implications for hand hygiene among clinicians, we explored the prevalence of face-touching behavior in medical students. in may 2010, a behavioral observation study was undertaken involving phase 3 medical students at the university of new south wales (unsw). ethical approval was obtained from the unsw human research ethics committee prior to the commencement of the study. the student cohort had completed a one 4-hour infection control course in the previous 12 months. the infection control course included education on hand hygiene, aseptic technique, standard precautions, and transmission-based precautions. the same student cohort attended two 2-hour lectures unrelated to infection control, on 2 separate occasions. one week before the 2-hour lecture commenced, students were informed that a behavioral observation study was being conducted during the lecture and required the students to be videotaped while they listened to the lecture. students were not informed about which behaviors were under observation to blind them from the aims of the study; this was necessary to minimize the potential for a change in behavior as a result of being observed. 13 to participate in the study, students were instructed to move to a marked area on the left side of the lecture theatre and complete a participant consent form. to opt out of the study, students were instructed to move to the right side of the lecture theatre outside of the videotape recording range. students were also informed that they could withdraw from the study once recording commenced by simply moving to the other side of the theatre. all participants consented prior to videotape recording. a digital videotape recording was made of the consenting participants and was viewed by investigators to record the facetouching behavior of every participant. for the purposes of precision, the digital recording was viewed multiple times after the lectures had taken place by 1 researcher (y.l.a.k.). a standardized scoring sheet was used to tally the frequency of hand-to-face contacts, the area of the face that was touched, whether a mucosal area (eyes, nose, mouth) or nonmucosal area (ears, cheeks, chin, forehead, hair) was touched, and the time in seconds of each contact. descriptive statistics were performed to determine the frequency and duration of touches per hour using spss version 21 for windows (spss inc, chicago, il). a total of 26 students were observed making 2,346 touches to the face over 240 minutes. of the face touches, 56% (1,322/2,346) involved nonmucosal regions, whereas 44% (1,024/2,346) involved contact with mucosal membranes. of the 1,322 nonmucosal membrane touches, most involved the chin (31%; 409/1,322), followed by the cheek (29%; 383/1,322), hair (28%; 369/1,322), neck (8%; 104/1,322), and ear (4%; 57/1,322). of the 1,024 touches involving a mucosal membrane region, 36% (372/1,024) involved the mouth, 31% (318/1,024) involved the nose, 27% (273/1,024) involved the eyes, and 6% (61/1,024) involved a combination of the mucosal membranes. during an average hour participants touched their face 23 times (median, 29.0 times; lq (lower quartile), 42.2; uq, 108.2; range, 4-153). the average duration of mouth touching was 2 seconds (median, 1 second; lq, 3.0; uq (upper quartile), 24.0; range, 1-12 seconds), the average nose touching duration was 1 second (median, <1 second; lq, 0.09; uq, 1.2; range, 1-10 seconds), and the average eye touching duration was 1 second (median, <1 second; lq, 3.0; uq, 11.5; range, 1-5 seconds). hands are considered a common vector for the transmission of health careeassociated infections 7, 14, 15 and have been implicated in the transmission of respiratory infections. 11, 14 good hand hygiene before and after patient contact is imperative to prevent transmission of infection. this is particularly so during the symptomatic or asymptomatic prodromal stages of infections when patients shed infectious material. 16 in particular, clinicians caring for infectious pediatric patients with high shedding concentrations 17,18 may be at risk of acquiring an infection if they have a high level of facetouching behavior. 19 s aureus is a common pathogen prevalent in both community and health care settings. colonization of the nasal mucous membranes with s aureus is common and ranges from 20%-30% in health care and community settings. 7 nose touching was common among our participants. this finding supports the importance of hand hygiene as a means of preventing occupationally acquired colonization with s aureus from patients or the contaminated environment. 8, 10, 20, 21 s aureus can survive for up to 5 years on hard surfaces, and no obvious role has yet been attributed to colonized staff. 7 when mixed with hospital dust, s aureus can still survive for >1 year until it is picked up from the environment. 22, 23 contaminated hands may act as a vector, transmitting the bacteria from a contaminated surface to the hcw's nasopharynx via face touching. high hand hygiene compliance before and after patient contact should reduce the likelihood of transferring pathogens through self-inoculation and in turn prevent inoculation of patients. 10, 24, 25 pathogens found on stethoscopes have also been recovered from physician's hands. 26 given the habitual face-touching behavior observed in our study, it is possible that the inoculation of stethoscopes and other contaminated medical equipment may have been the result of inoculation from nose touching to hands and subsequently to the stethoscope. given the frequency of facetouching behavior observed in this study, clinicians must practice hand hygiene before and after using such equipment to ensure that patient equipment is kept clean prior to use. given the high frequency of mouth and nose touching observed, 4 times per hour on average for mouth touching and 3 times per hour on average for nose touching, performing hand hygiene is an essential and inexpensive preventive method for breaking the colonization and transmission cycle. models of infection transmission and comparison of transmission efficiency of self-inoculation against other transmission routes are required to further expand our knowledge on the role of face touching for self-inoculation. meanwhile, raising awareness that face-touching behavior is common and is a possible vector in self-inoculation could result in hcws accepting the message that hand hygiene before and after patient contact is an effective method of reducing colonization and infection transmission for themselves and their patients. a study quantifying the hand-to-face contact rate and its potential application to predicting respiratory tract infection a survey of knowledge, attitudes and practices towards avian influenza in an adult population of italy environmental contamination with rhinovirus and transfer to fingers of healthy individuals by daily life activity transmission of experimental rhinovirus infection by contaminated surfaces preventive behaviors and mental distress in response to h1n1 among university students in guangzhou china microbiology survey reveals that as many as 30 percent of travelers don't wash hands after using public restrooms at airports the role of nasal carriage in staphylococcus aureus infections nasal carriage of staphylococcus aureus including community-associated methicillin-resistant strains, in queensland adults importance of the environment in methicillin-resistant staphylococcus aureus acquisition: the case of a hospital cleaning the prevalence of nasal carriage of staphylococcus aureus among healthcare workers at a tertiary care hospital in assam with special reference to mrsa controlling the novel a (h1n1) influenza virus: don't touch your face! my five moments for hand hygiene': a user-centered design approach to understand, train, monitor and report hand hygiene a dictionary of epidemiology evidenceebased model for hand transmission during patient care and the role of improved particles nasal and hand carriage rate of methicillin resistant staphylococcus aureus (mrsa) among healthcare workers in mekelle hospital, north ethiopia clinical signs and symptoms of influenza: influenza prevention & control recommendations rhinovirus transmission within families with children: incidence of symptomatic and asymptomatic infections clinical effects of rhinovirus infections survival of influenza virus on human fingers methicillin resistant staphylococcus aureus: carriage rates and characterization of students in a texas university studies of the community and family: acute respiratory illness and infection the staphylococci in human disease tackling contamination of the hospital environment by methicillin-resistant staphylococcus aureus (mrsa): a comparison between conventional terminal cleaning and hydrogen peroxide vapor decontamination the public hand hygiene practices of new zealanders: a national survey hand hygiene and face touching in family medicine offices: a cincinnati area research and improvement group (caring) network study contamination of stethoscopes and physicians' hands after a physical examination we thank professor gary velan for providing us access to the unsw medical students prior to his lecture and to professor william rawlinson for providing recording equipment. key: cord-339362-crtlkju1 authors: pryor, rachel; atkinson, connie; cooper, kaila; doll, michelle; godbout, emily; stevens, michael p.; bearman, gonzalo title: the electronic medical record and covid-19: is it up to the challenge? date: 2020-05-12 journal: am j infect control doi: 10.1016/j.ajic.2020.05.002 sha: doc_id: 339362 cord_uid: crtlkju1 • improvements to the electronic medical records must occur prior to the next pandemic; • during pandemics, infection preventionists’ should advise staff, not review charts; • automation can help improve healthcare safety and quality;  improvements to the electronic medical records must occur prior to the next pandemic  during pandemics, infection preventionists' should advise staff, not review charts  automation can help improve healthcare safety and quality "starting now and lasting until forever, your health and healthcare will be determined, to a remarkable and somewhat disquieting degree, by how well the technology works." -robert wachter, the digital doctor: hope, hype, and harm at the dawn of medicine's computer age despite benefits such as improved patient care coordination and access to patient information, 1 the electronic medical record (emr) in its current state poses significant barriers to infection preventionists' (ip) work efficiency during a pandemic. the 2019 coronavirus disease pandemic underscores both the importance of ips to the healthcare system and the need for an everstrengthening partnership between ips and information technology (it). many aspects of ips day-to-day work involves manual surveillance to determine whether an infection is hospital-acquired. hospitalacquired infections are infrequent events, allowing for a manageable combination of ip surveillance via manual and automated processes. the reliance of manual case identification differs in a pandemic as suspected or confirmed covid-19 cases are increasingly frequent, real-time events. increased covid-19 testing highlights emr barriers to effective infection prevention practices. prior to future pandemics, healthcare systems must anticipate emr barriers and design solutions in advance. electronic medical record barriers highlighted during the covid-19 pandemic include rapid notification of suspected or confirmed covid-19 patients, tracking suspect or confirmed cases who have been tested at an outside facility or during a previous hospital visit, and triggering the automatic implementation of isolation orders (table 1) . rapid stakeholder notification of suspected or confirmed covid-19 patients is a significant covid-19 emr barrier. no standard, centralized emr view is accessible to all hospital teams (ips, providers, frontline staff, research coordinators, dietary, bed management, environmental services, nursing education, etc.). this barrier creates confusion which only increases as covid-19 test volume surges. differing hospital departments use different emr screen views and/or patient-tracking systems for information management. communicating standardized, urgent, and specific information to a diversity of hospital teams across a non-standardized platform is ineffective. because most emrs do not communicate between health systems, delayed ip notification of suspected or confirmed covid-19 patients at the time of facility-to-facility transfer may hinder prompt application of appropriate isolation precautions and lead to staff exposure. when clinical teams approve a hospital-to-hospital transfer of a suspected or confirmed covid-19 patient there is no consistent system in place to notify ips. neither communications specialists working in the patient transfer center nor accepting providers reliably notify ips of patient transfers. human error and omissions are a challenge to standardized processes. it is unrealistic to expect individual healthcare workers to reliably provide notifications in a large tertiary care center -any notification that is important needs to be automatically triggered in the emr. this is particularly true when there is not the time to educate all staff members on ongoing major process changes in the midst of an epidemic. ideally, the emr would notify ips of a covid-19 person under investigation (pui) or positive case at the time of patient transfer approval. when covid-19 pui incidence was low, coinciding with low nation-wide testing capacity, infectious disease (id) physicians screened each potential covid-19 pui before determining if the patient met centers for disease control and prevention criteria for testing. once our institution's clinical microbiology laboratory began in-house testing, covid-19 polymerase chain reaction testing capacity increased. the arrival of in-house covid-19 testing resulted in significant test volume with logistical and ip oversight issues for proper patient isolation. by removing the id physician hard stop, providers ordering covid-19 testing no longer consistently alerted the infection prevention program, nor was there an emr notification system in place to alert ips of new covid-19 orders. when the infection prevention program was unaware of covid-19 pui status at the time of test order entry, real time guidance and implementation of isolation precautions was both delayed and poorly coordinated. tracking the location of covid-19 positive and puis in real-time is a formidable challenge. initially ips at our facility tracked patients by inputting data to a computer-based spreadsheet; however, this approach became challenging to update regularly as patient volume increased. because the ip in our incident command center spends a significant portion of time providing guidance to frontline providers and staff, performing regular emr chart reviews to check current patient location was untenable. when our facility began testing patients for covid-19, the emr did not have the capacity to create a patient tracking list for diagnoses of interest. typically, patient tracking lists are sorted by provider service or patient unit. creating an automated list that updates in real-time is a time-consuming endeavor involving collaboration with it partners. modifications to emrs traditionally take weeks to months and have pre-scheduled time to validate the new process and resulting data. during a pandemic, the delayed timeline is not opportune. notification of patient isolation needs to frontline staff in real time via the emr is yet another barrier highlighted during the covid-19 pandemic. programing a new rule in the emr is time consuming. in their current state, many emrs are not nimble enough to program an automatic isolation order when a provider orders a covid-19 test, something that is critical during an escalating pandemic. upon ordering a covid-19 test, the provider or an ip must then order appropriate isolation. appropriate isolation orders are communicated to frontline staff via verbal notification (or a manual emr chart review performed by frontline staff), rather than an emr pop-up alert. this may lead to confusion about whether patients should be isolated, which isolation type is appropriate and when isolation should be discontinued. patient isolation confusion may result in unnecessary staff exposure or overuse of personal protective equipment. this issue is compounded when strategies regarding isolation and patient cohorting are frequently changing, as has been seen in the setting of the current pandemic. we summarize emr barriers during a response to the covid-19 pandemic. these barriers include notification and identification of covid-19 pui and positive patients, tracking infected and suspected inpatients and inter-facility transfers and ensuring proper isolation orders are executed. finding solutions to these barriers is time-intensive both in the present and in the face of future infectious diseases threats. ideally, the infection prevention-emr barriers exposed by a pandemic are anticipated and solutions are sought prior to a wave of infected cases. even with emr solutions in place, responses to the covid-19 pandemic must be nimble as situations and processes change. infection prevention efforts are misguided when ips spend valuable time performing manual data entry and chart review that can be alleviated through emr solutions. thus, the fluidity of hospital pandemic responses underscores the need for present and sustained strengthening of the ip-it partnership. technology should synergize with ip teams to maximize emr solutions such that ip team members are free to focus on nuanced, real time pandemic management issues. to do so, emr enhancements during the current pandemic must be institutionalized and critical functions of the emr in future infection prevention emergency preparedness planning should be deliberately defined and developed. electronic health records implementation: an evaluation of information system impact and contingency factors key: cord-290257-2u228xe9 authors: hsu, chih-cheng; chen, ted; chang, mei; chang, yu-kang title: confidence in controlling a sars outbreak: experiences of public health nurses in managing home quarantine measures in taiwan date: 2006-05-05 journal: am j infect control doi: 10.1016/j.ajic.2005.11.008 sha: doc_id: 290257 cord_uid: 2u228xe9 background: taiwan experienced one of the most serious outbreaks of severe acute respiratory syndrome (sars) during the 2003 epidemic. public health nurses faced unprecedented challenges in implementing an extensive quarantine policy to prevent disease spread. their professional confidence, however, was shattered during the sars crisis. this paper assesses factors related to public health nurses' confidence in managing community sars control programs. methods: in may 2003, we sent structured questionnaires to all 361 health centers in taiwan and asked the public health nurses responsible for epidemic control to complete. a total of 312 completed surveys were returned for a response rate of 86.4%. descriptive methods and logistic regression were used to analyze the data. results: most public health nurses (71.9%) expressed a general lack of confidence in handling the sars epidemic. confidence was significantly associated with perceived epidemic severity (or, 0.58; 95% ci: 0.35-0.99), daily epidemic updates (or, 2.26; 95% ci: 1.28-3.98), and number of cases in the community (or, 2.21; 95% ci: 1.13-4.31). conclusion: nurses' individual risk perception and prompt update of epidemic information significantly affect levels of professional confidence, a key factor influencing quarantine implementation success. strategies to promote productive interagency collaboration and advocate participatory policy making involving health workers at all levels are needed to control effectively infectious disease outbreaks. the global spread of severe acute respiratory syndrome (sars) in 2003 was a prelude to other emerging infectious diseases in the 21st century. 1 recent outbreaks of h5n1 avian influenza in asia continue to remind the world of the threat of periodic and unpredictable recurrences of pandemic contagion. 2 since the beginning of the sars outbreak, many scientists have worked to characterize the coronavirus, 3, 4 trace epidemic patterns, 5 and synthesize potential vaccines to prevent further outbreaks. 6, 7 however, the global experience of managing sars has revealed that reducing contact between people by implementing quarantine measures is as important as discovering effective remedies. 8, 9 taiwan reported 346 probable sars cases and 73 sars-related deaths during the outbreak in 2003, making it one of the most serious sars epidemic areas in the world 10, 11 figure 1 shows the chronology of the 2003 sars epidemic in taiwan. facing this unprecedented outbreak, the taiwan government began implementation of compulsory home quarantine on march 28 to stop community transmission. 12 individuals who were suspected to have been infected with sars were quarantined at home (or in special facilities) for 10 to 14 days. in those 4 months of the epidemic period, 131,132 individuals were quarantined in taiwan. this includes 50,319 people who had close contact with sars patients and 80,813 travelers who came to taiwan from world health organization (who)-designated sars-affected areas. 11, 13 public health administration in taiwan is organized at 3 levels: national, city/county, and township. generally speaking, national health policies are often formulated in the national department of health (doh) with participation of city/county health bureau officials. the health centers (or health stations, as they are called) are the local agencies situated in the townships. the major responsibility of health centers is to implement public health protocols developed at the national and city/ county levels. the directors of health centers are usually licensed physicians. public health nurses are usually the supporting staff who carry out program assignments. the public health operation in taiwan is managed under this clear chain of command. under this system, taiwan eradicated malaria infection in the 1960s, succeeded in having 82% of all married women aged 22 to 39 years practice contraception in the 1970s, and dropped 84% of hepatitis b carriers in the 1980s. public health nurses working at the local health centers played a key role in achieving public health success in taiwan. 14 however, the public health nurses were unprepared in 2003 at the time of the sars crisis. sars hit taiwan in march 2003. in response to the outbreak, the doh created an emergency operation office and appointed an anti-sars task force commander to direct a comprehensive national sars control program. home quarantine was ordered for all suspected sars cases. health centers at all localities were asked to implement the home quarantine policy. local public health nurses were not invited to participate in the national sars control policy making but were requested to carry out the mission. during the quarantine period, public health nurses were requested to undertake several public health measures, which included conducting initial registration, maintaining daily temperature records, disposing of personal trash, and providing social support and advice on medical care to those with a fever or sars-related symptoms. success in quarantine management was considered a crucial factor in the successful control of sars. however, it was soon evident that public health nurses' lack of experience in managing community quarantine and their fear of being infected with sars presented a major challenge. this study was designed to understand better the challenges and threats facing public health nurses responsible for implementing sars quarantine procedures. the results will be valuable for developing better strategies for controlling the rapid spread of infectious diseases such as sars. an attitudinal questionnaire was developed by researchers in may 2003 at the peak of the taiwan sars epidemic. questionnaire items were designed on the basis of the working experience of a panel of public health nurses. the questionnaire went through a content validation process. six experts from public health or community nursing fields served as the expert panel in checking the validity of questionnaire items. the drafted questionnaire was piloted for understandability among 5 public health nurses in northern taiwan. moreover, within 1 week after the questionnaires were returned, the researchers randomly selected and phoned 32 respondents (approximately 10% of the total) to check the reliability of their written answers. the test/retest reliability for this questionnaire was high (pearson correlation coefficients for continuous variables: 0.87-0.97; spearman rank correlation coefficients for categorical variables: 0.90-0.97). one section of the questionnaire was designed to collect baseline information, including (1) demographics, (2) number of quarantined cases managed and responsibilities within the previous week (itemizing quarantine-related extra workload), and (3) the date the nurses predicted sars epidemic would end. another section (using categorical scales) asked about sars-related operations that included the frequency of (1) epidemic information updated in the health center, (2) sars-related training courses received, and (3) assistance of community volunteers on quarantine measures. the third section contained questions (using 10-point likert scale: 1 5 the worst to 10 5 the best) about the effectiveness of the nurse's institution in managing the sars epidemic, including the nurse's assessment of (1) the institutional functioning on community home quarantine, (2) the quality of training received for controlling infectious disease outbreaks, and (3) the adequacy of support (for both manpower and financing) received from superior health agencies force commander said the epidemic situation was stable and advised people to return to their routine. (e) who removed taiwan from its list of areas to which travelers were advised to avoid for all but essential travel. (doh or city/county health bureaus). in the fourth section of the questionnaire (also using 10-point likert scale), the nurses were asked to assess the severity of the epidemic, the public's awareness of the epidemic situation, the public's fear of sars, and the public's compliance with official quarantine measures. finally, the nurses were asked to list major difficulties they encountered in managing the sars epidemic. the main island of taiwan has a total of 361 health centers. on may 26, 2003, 1 questionnaire was mailed to each of the 361 health centers to be completed by the head nurse or the nurse in charge of sars epidemic control. a reminder letter was sent 1 week later to nonresponding centers. a total of 312 completed surveys were returned for a response rate of 86.4%. logistic regression was used to identify variables associated with the nurses' lack of confidence in sars control. nurses who estimated that the sars epidemic would not be declared ''ended'' by the who until mid-september 2003 or later (the who declared taiwan sars free on july 5) were categorized as ''less confident.'' logistic regression also identified variables associated with public compliance of official anti-sars measures. variables in univariate models that exerted a significant effect were subjected to multivariate logistics to assess significance level. statistical analyses were performed using sas 8.01 (sas institute inc., cary, nc). all reported p values were 2-sided; p , .05 was considered statistically significant. table 1 , approximately half (49%) of the respondents were 40 to 49 years of age, one third (33%) 30 to 39 years, and 15% older than 50 years. most respondents (70%) had at least 10 years of experience working in a health center. approximately 28% of respondents believed the sars outbreak would be controlled by mid-july; the remainder of the respondents believed control would not occur until mid-september (38%), mid-december, or later (29%). many public health nurses encountered difficulties while performing sars-related duties. they expressed dissatisfaction with the shortage of protective equipment such as n95 masks and gloves (44%), public resistance to following protection measures (42%), poor interagency communication (37%), and lack of standard operating procedures (30%). as shown in table 2 , nurses' perceptions of epidemic severity were negatively associated with confidence that the epidemic could be controlled (or, 0.58; 95% ci: 0.35-0.99). nurses in health centers receiving fewer epidemic updates were more likely to doubt the effectiveness of epidemic control measures (or, 2.26; 95% ci: 1.28-3.98). nurses working in areas with relatively fewer probable sars cases were less confident in control efforts (or, 2.21; 95% ci: 1.13-4.31). several factors contributed to the public's lack of cooperation with sars-related home quarantine measures (table 3 ). according to the nurses, people were less likely to cooperate with quarantine measures when (1) they were less knowledgeable about sars (or, 3.66; 95% ci: 1.99-6.75), (2) they expressed less fear of sars (or, 3.39; 95% ci: 1.85-6.21), (3) the health centers were not functioning well (or, 2.16; 95% ci: 1.17-4.00), and (4) the health centers received inadequate manpower or financial support from higher health authorities (or, 2.67; 95% ci: 1.33-5.38). this study is the only study reporting on the assessment of frontline nurses' reactions to home quarantines implemented by most health centers in taiwan during the 2003 sars outbreak. survey respondents were mainly head nurses with more than 10 years of health center experience and were very familiar with their organizations, clients, communities, and issues surrounding quarantine operations. furthermore, because they were required to interact directly with quarantined persons, they had the best opportunity to understand the community's response to the sars outbreak. 15 also, because the survey was conducted just after the sars epidemic had peaked, the related experiences were fresh in their minds, and recall bias would have been minimal. therefore, this report can be a valuable reference for the control and management of sars-like contagious disease outbreaks. the who removed taiwan from its list of sarsinfected areas on july 5, 2003 16 ; however, even at the beginning of june, many taiwanese, including public health officials and lay people, remained pessimistic about the success of sars control measures. as shown in table 1 , most public health nurses (71.9%) believed that the outbreak would not end until mid-september or even later. there was at least a 2-month difference between frontline nurses' estimates and the actual timing of the epidemic's end, indicating a low confidence level on the part of the nurses. this is serious because the pessimistic attitudes of nurses could affect the morale of quarantined subjects, people in the community, and, eventually, the success of the sars control program. why did public health nurses lack confidence in implementing the anti-sars program? as shown in table 2 , individual risk perception, working environment of the health centers, and epidemic severity in the community were contributing factors. during the sars epidemic, the taiwan government made efforts, via media announcements, to assure the public that the situation was under control. from may 2003, all major television channels broadcast daily the ''sars front-line'' program on the evening news. the premier and the commander of the anti-sars task force also repeatedly delivered public announcements that said the outbreak would soon be over. [17] [18] [19] however, these optimistic public announcements were not always trusted by frontline nurses. the daily epidemic reports received by the nurses always seemed to be outdated. as the severity of the epidemic lessened day by day, the outdated data that showed a more severe phase of epidemic were counterproductive to boosting nurses' trust in the government's optimistic announcements. it appears that providing public health nurses with rapidly updated information is of utmost importance. results also show that risk communication at the time of infectious disease outbreak should be based on timely, rapidly updated, and evidence-based data to supplement routine government announcements. we determined whether nurse confidence in epidemic control measures was a function of extra hours and activities required for managing the epidemic. results indicated that lower confidence levels were associated with fewer cases in the community (table 2) . without an immediate threat, health centers in counties/cities with few sars cases might not have fully mobilized their community resources to prepare the public or their nurses for sars prevention and control measures. because the national media broadcasted sensationally on the severity of sars epidemics, public health nurses without sufficient preparation and support might have been more vulnerable to rumors and speculation about negative aspects of the outbreak such as mortality rate, resulting in a loss of confidence in organized efforts to control the sars epidemic. another factor contributing to nurses' low confidence may be related to their lack of opportunity to participate in the formation of national policy, which they are asked to implement at the local level. according to the aforementioned traditional chain of command in the taiwanese public health bureaucracy, when the sars policy was developed, standard procedures for field operations were decided by the national office. without having policy fine-tuned with input from frontline nurses, this top-down policy could not promptly respond to local needs that changed rapidly according to the disastrous nature of sars contingencies. it is obvious that the long-established champion of the taiwanese public health system needs an effective feedback mechanism to renovate its response to newly emerging infectious outbreaks. a platform that encourages participatory decision making involving health professionals at all levels should be critically emphasized in developing a national policy to control sars-like outbreaks of pandemic contagion. frontline nurses reported that one of the most frustrating experiences during the sars epidemic was the reluctance of people to follow quarantine guidelines. this was independent of local epidemic severity but significantly related to people's cognitive preparedness and the efficiency of interagency collaborations (table 3) . quarantine restricts the movement of people who can potentially expose others to a disease. 20, 21 how to implement effectively a community-wide quarantine therefore presents a major challenge to health agencies. table 3 shows that people who were less knowledgeable about the sars outbreak and those who expressed little fear of infection were less compliant in following anti-sars measures. in the future, more efforts should be placed on educating people to increase their health knowledge and beliefs, especially about risk susceptibility and severity, and belief in the benefits of taking health actions. 22, 23 moreover, effective community health education programs that emphasize community-based participatory research and education should be considered. 24, 25 from a national perspective, a comprehensive sars control strategy should also be developed that would streamline communication and resource sharing among health agencies at all levels. in summary, public health nurses' confidence in the control of a sars outbreak and people's compliance with quarantine measures are 2 major factors that can affect the success of a sars-control program. other important determinants to a successful program include effective risk communication, participatory policy making that involves health workers at all levels, and intergovernmental collaboration at national and local levels. factors critical to sars management are similar to those for crisis management of avian influenza outbreaks and of the results of terrorist acts. [26] [27] [28] [29] lessons learned in this study can serve as useful guidelines to prevent and manage emerging infectious disease outbreaks. sars: unprecedented global response to a newly emerging disease avian influenza and pandemics sars virus: the beginning of the unraveling of a new coronavirus sars: beginning to understand a new virus a double epidemic model for the sars propagation current concepts in sars treatment treatment of sars with human interferons evaluation of control measures implemented in the severe acute respiratory syndrome outbreak in beijing preventive strategies to keep saudi arabia sars-free information below was mainly re-classified according to the current sars definition and test results in laboratory from who. center for disease control taiwan basars%ac%db%c3%f6%b8%ea%b0t/%a5x%c6wsars%ac% control measures for severe acute respiratory syndrome (sars) in taiwan use of quarantine to prevent transmission of severe acute respiratory syndrome-taiwan health care system in a transitional society: a taiwan experience. a conference speech delivered at the international research foundation for development sars: a perspective from a school of nursing in hong kong china: sars transmission interrupted in last outbreak area who estimated that the taiwan epidemic situation might be under control in six to seven weeks the premier said that the outbreak would be over by the end of the chief commander of anti-sars project in taiwan said it did not need seven weeks to control the outbreak efficiency of quarantine during an epidemic of severe acute respiratory syndrome community based participatory research: a promising approach for increasing epidemiology's relevance in the 21st century community-based participatory research: an approach to intervention research with a native american community who views on perspectives in health informatics introduction to community empowerment, participatory education, and health the public and effective risk communication communicating risk: wireless and hardwired public reliance on risk communication channels in the wake of a cryptosporidium outbreak bioterrorism risk communication policy key: cord-291650-1qy6y7f0 authors: butt, taimur s.; koutlakis-barron, irene; aljumaah, suliman; althawadi, sahar; almofada, saleh title: infection control and prevention practices implemented to reduce transmission risk of middle east respiratory syndrome-coronavirus in a tertiary care institution in saudi arabia date: 2016-05-01 journal: am j infect control doi: 10.1016/j.ajic.2016.01.004 sha: doc_id: 291650 cord_uid: 1qy6y7f0 background: transmission of middle east respiratory syndrome-coronavirus (mers-cov) among health care workers (hcws) and patients has been documented with mortality rate approximating 36%. we propose advanced infection control measures (a-ic) used in conjunction with basic infection control measures (b-ic) help reduce pathogen transmission. b-ic include standard and transmission-based precautions. a-ic are initiatives implemented within our center to enhance effectiveness of b-ic. objective: study effectiveness of combining b-ic and a-ic to prevent transmission of mers-cov to hcws. methods: a retrospective observational study was undertaken. a-ic measures include administrative support with daily rounds; infection control risk assessment; timely screening, isolation, and specimen analysis; collaboration; epidemic planning; stockpiling; implementation of contingency plans; full personal protective equipment use for advanced airway management; use of a real-time electronic isolation flagging system; infection prevention and control team on-call protocols; pretransfer mers-cov testing; and education. results: a total of 874 real-time polymerase chain reaction mers-cov tests were performed during the period beginning july 1, 2013, and ending january 31, 2015. six hundred ninety-four non-hcws were tested, of these 16 tested positive for mers-cov and their infection was community acquired. sixty-nine percent of the confirmed mers-cov-positive cases were men, with an average age of 56 years (range, 19-84 years). of the total tested for mers-cov, 180 individuals were hcws with zero positivity. conclusions: adhering to a combination of b-ic and a-ic reduces the risk of mers-cov transmission to hcws. transmission of middle east respiratory syndrome-coronavirus (mers-cov) among health care workers (hcws) and patients in hospitals within saudi arabia has been documented. 1 of the hcws who have acquired this infection, more than 63% acquired the infection within saudi arabia, where the majority of mers-cov cases have been reported. 2 as of june 20, 2015, 1,338 cases have occurred worldwide, and of these 77.5% (n = 1,038) were identified within saudi arabia. 3, 4 the main contributing factor for health care-associated transmission and causality of outbreaks among saudi hospitals is due to emergency department (ed) overcrowding and poor ventilation. 5 in turn, this can be a reflection of institutional overcrowding, inpatient bed occupancy reaching or exceeding full capacity, and/or a lack of compliance to and understanding of the importance of implementing infection control and prevention (icp) measures. this belief is supported by internationally recognized agencies, including the world health organization (who) and the us centers for disease control and prevention. the organizations support the practice of adhering to icp measures. basic infection control measures (b-ic), defined as standard and transmissionbased precautions, play a major role in preventing and controlling pathogen spread, including adherence to hand hygiene, environment and equipment cleanliness, use of personal protective equipment (ppe) such as high-efficiency particulate respirators (eg, n-95 or r-95), and adhering to respiratory/cough etiquette. 6 we propose that the spread of mers-cov among hcws is preventable when b-ic are used in combination with institution-specific advanced infection control measures (a-ic). in this article, a-ic implemented in a tertiary care hospital during a time of epidemic is described. during the initial and intermediate period after discovering this novel virus during june 2012 it was noted that symptoms and complexity of patients presenting with infection were variable. 7 this resulted in a case definition that required modification over time to allow for broader screening of patients with flu-like illness. the initial case definition mainly encouraged screening of patients with severe acute respiratory illness requiring intensive care unit (icu) admission. 3 in the authors' experience, in dealing with mers-cov cases in the early stages of disease recognition there were poorly established systems in place for identification of suspected/confirmed cases. we believe that this was due to an unclear incubation period, poor rapid implementation of isolation precautions and use of ppe, and the unavailability of diagnostic testing among regional health care facilities. these health care facilities relied on an inconsistent availability of appropriate packaging and transportation of specimens to approved ministry of health (moh) reference laboratories for testing of samples. consequently, there were delays in communication and appropriate isolation of positive cases resulting in spread of infection to hcws. 1 b-ic are well-recognized preventative measures considered the minimum requirement for infection prevention and control. 6, 8 a-ic are institution-specific measures that enhance b-ic to further reduce the risk of transmission. b-ic are based on key components of standard precautions and recommended transmission-based precautions for prevention and control of transmissible diseases. this includes appropriate hand hygiene practices; proper cleaning of the environment and equipment; prompt initiation of transmission-based precautions for suspected/confirmed cases until noninfectious; segregation of confirmed/suspected cases in waiting areas; use of single hospital patient rooms; and proper availability, quality, type, and use of ppe 6,9 (table 1) . a-ic is a group of institution-specific measures that go above and beyond b-ic and enhance their effectiveness. it is vital that administrative support is sought to approve and fund the necessary initiatives. the following outlines the a-ic measures adopted at our institution (table 1). 1. interdepartmental collaborative meetings: as part of the established institutional epidemic plan, using both interdepartmental collaboration and institutional expertise, daily morning meetings are held. these meetings are undertaken at a time of high incidence within the community, other regional institutions, or when an alert has been issued by the moh. key members include hospital administration, senior staff from the infectious diseases department, icp, ed, icu, nursing, microbiology, case management, and others as deemed necessary. their objective is to assess, monitor, and recommend risk mitigation strategies. current regional and international information regarding mers-cov disease activity, institutional preparedness, and its capabilities are discussed. during these meetings initiatives are formulated, implemented if applicable, and evaluated for success and/or modification. measures to reduce risks referred to in this article as a-ic were discussed in these meetings and implemented institution-wide. wide infection control risk assessment to address areas of concern was undertaken. areas of deficiencies addressed at the organization level include insufficient number of staff in highrisk areas, fit testing for high-efficiency particulate respirators (especially for ed, icu, and direct patient care providers), overcrowding in the ed, ventilation systems in the ed, extended turnaround time of mers-cov test results, and awareness of the importance of early identification and isolation of suspected cases. with each automated telephone text message reminder of upcoming clinic or admission came an additional reminder to inform staff of any flu-like illness upon arrival. this is in conjunction with a prescreening process established in the ed and clinic receptions. implemented as an extension of the existing institutional epidemic plan ( e. patient transportation: isolation transportation pods were purchased to be used for transportation of any patient suspected or confirmed positive for an airborne infectious disease, including mers-cov. during epidemic plan activation a disease-specific education campaign is implemented. posters, pamphlets, and the intrahospital television system are used for communication (fig 2) . 14. staff education and communication: staff preparation training and specific education to care for patients with/suspected mers-cov was undertaken. 15. transparency: while maintaining confidentiality, transparency is important to enhance dissemination of accurate information to all staff. this can create an atmosphere of trust, loyalty, and support; therefore, hcws are more likely to adhere to recommendations and reduce their absenteeism. method icis was used to retrieve patient and hcw data. for the purpose of this observational study, data were retrieved retrospectively and collected for a continuous period of 19 months. those tested for mers-cov included patients with suspected/confirmed cases who met the case definition and/or hcws who were tested during an outbreak investigation for protected/unprotected exposure. duplicate tests were removed if testing was performed during the same episode of illness or exposure. all patient and hcw confidentiality and rights were maintained. microsoft office (redmond, wa) and visio (microsoft, redmond, wa) were used to plot results and research advisory committee approval (rac# 2151-194) was obtained to use the data for this publication. a total of 874 cases were tested for mers-cov from the period beginning july 1, 2013, and ending january 31, 2015. of these, 16 (1.8%) were mers-cov positive. they were all non-hcws (fig 3) . during this time period the ed served more than 80,000 patients and institutional inpatient bed capacity was >700 with an occupancy rate consistently >90%. institution employee numbers exceeded 11,000. of the 874 mers-cov samples tested, 180 (21%) were from hcws. hcw testing was due to meeting the case criteria or to protected/ unprotected exposure. exposure occurred in 3 of the confirmed cases as a result of a delay in the initiation of isolation precautions due to lack of early recognition of symptoms or incubation period. testing of the non-hcws (n = 694) was due to case criteria being met during admission or upon presentation to the institution through the ed or clinics, or as part of a screening requirement at the time of admission; that is, direct admission from another hospital per the epidemic plan. the majority of patients with positive cases were men (69%) with a mean age of 56 years (range, 19-84 years). all case patients except 1 had comorbidities and/or immunocompromised status. ten of the 16 patients with confirmed cases died (62%). mortality was directly or indirectly attributed to complications that developed as a result of mers-cov infection. all case patients had respiratory symptoms on initial presentation except for 1 patient who was admitted for elective surgery and developed respiratory symptoms with fever postoperatively on day 7. this was considered community acquired because the incubation period overlapped with the preadmission period. no cases were considered health careassociated infections (table 3) . potential hcw exposure days are calculated from the date of mers-cov symptom onset while in hospital until either the date of negative screening result(s) or death while positive. during the period of study the potential hcw exposure days totaled 338. the mean duration of potential infectivity per case was 21 days (range, 4-57 days). due to the nature of their work, hcws remain at high risk of acquiring communicable diseases from occupational exposure. experience and data collected during the severe acute respiratory syndrome epidemic in hong kong suggests an infection rate of 22% among hcws. 11 during april-august 2014 a number of hospital outbreaks were reported within saudi arabia increasing the risk of hcw exposure. this risk to hcws is supported by ongoing findings reported by the who. the mers-cov situation update report-15 june 2015 12 states that 10%-29% of the total mers-cov cases identified in saudi arabia were in hcws. front-line hcws caring for undifferentiated and severely ill patients who do not adhere to icp measures are at the highest risk. 10 upon the discovery of the novel coronavirus and in anticipation of a local and regional threat, a taskforce was formed to evaluate our institution's readiness to deal with the developing situation and to initiate proactive measures to protect staff, patients, and visitors. this taskforce included representatives from experts from the infectious disease department (adult and pediatric), icp, ed, laboratory, nursing, research, supply chain, and other relevant stakeholders. this article reflects the work undertaken by the taskforce members who recommended and implemented measures to mitigate the risk of viral spread. although institutions aim to protect and safeguard their hcws against communicable diseases, success is not always attainable without a culture of vigilance. the approval by executive management to implement the recommended icp measures was primarily due to recognition of a true potential threat, and in support of recommendations by the taskforce. this prompt action and support is reflective of the mission, vision, and core values of our institution, which supports a culture of safety. due to urgency, time for a prescheduled mock drill to test proposed interventions and make the necessary adjustments based on the results of the simulation was not possible at time of initial implementation. changes or improvements to icp measures occurred in real time with immediate effect. ongoing monitoring for effectiveness occurred through observational hcw compliance monitoring, noting frequency of unprotected exposure events, and screening during outbreak investigations. those working in our institution-especially within high-risk areas (eg, ed and icu) observed an increased level of anxiety reflected by an increased use of masks while not performing direct patient care. in particular, in the use of high-particulate respirators. in our opinion this anxiety was as a result of rumors and misconceptions of mers-cov transmission and number of actual cases within our institution, documented human-to-human and animal-to-human transmission, a high mortality rate (36%) that includes hcws, limited treatment options, and the unavailability of vaccines. 4 communication and transparency helped to reduce levels of anxiety and rumor. our reported mers-cov mortality rate of 62% is higher than that reported nationally and most likely due to the complexity and comorbidities of the patient population served in our major city tertiary care institution. there were 16 confirmed mers-cov cases over a 2-year period with a collective potential infectivity duration of 338 days. none of the confirmed cases were health care-associated infections or hcws from this institution. as reflected in table 3 , cases identified in 2013 from date of admission to date of first mers-cov sample took longer than what was observed in subsequent years. this reflects the successful work of the taskforce. b-ic were already in place but required reinforcement. standard and transmission-based precautions, and hand hygiene are icp key performance indicators for continual compliance monitoring and reporting. 13, 14 a-ic were introduced and reinforced to support the b-ic measures. many of the a-ic measures implemented during this period have now become standard-of-care practices within the institution. without administrative and leadership support, targeted resource allocation, and high hcw compliance rates, icp measures would not be effective. this includes timely information dissemination, investment by the institution on education, ongoing awareness and staff development, adequate and high-quality supplies, and meticulous screening processes. clear and open communication channels are vital between all parties and are a prerequisite for success. close contact with the moh was maintained both in reporting of cases and receiving directives for case identification and management. in addition, updates posted by the who and centers for disease control and prevention were reviewed on a daily basis to remain current and monitor for changes to guidelines, and in the understanding of the disease processes. adjustments were made ac-cordingly to institutional case definitions, management guidelines, and icp measures. no outside consultation was undertaken to develop and refine the a-ic measures. this was a single-center study; therefore, results may not be generalized to other institutions. the actual level of compliance and benefits of implemented icp measures were not systematically measured because a randomized control study would be unethical. seroconversion rates for mers-cov were not undertaken among hcws because this test is currently unavailable within our institution. our institution successfully reduced the transmission risk of mers-cov among hcws and patients. we believe that our success is multifactorial, including a proactive and visionary response by leadership, collaborative efforts by all departments, and staff adherence to both b-ic and a-ic measures. we suggest that other institutions under similar circumstances conduct an internal review as soon as possible and implement appropriate measures accordingly. to our knowledge, a similar experience of preventing the spread of mers-cov through the implementation of both b-ic and a-ic has not been published. ksa mers-cov investigation team. hospital outbreak of middle east respiratory syndrome coronavirus severe respiratory disease associated with middle east respiratory syndrome coronavirus (mers-cov)-tenth update infection prevention and control guidelines for middle east respiratory syndrome coronavirus (mers-cov) infection coronamap realtime tracking of mers corona virus on world map. as of infection control and mers-cov in health-care workers guideline for isolation precautions: preventing transmission of infectious agents in healthcare setting. the healthcare infection control practices advisory committee state of knowledge and data gaps of middle east respiratory syndrome coronavirus (mers-cov) in humans infection prevention and control during health care for probable or confirmed cases of novel coronavirus (ncov) infection interim guidance 6 interim infection prevention and control recommendations for hospitalized patients with middle east respiratory syndrome (mers-cov) pandemic (h1n1) 2009 risk for frontline health care workers clinical management and infection control of sars: lessons learned world health organization. mers-cov situation world health organization. clean care is safer care commentary: protecting health workers from airborne mers-cov-learning from sars, centers for infectious disease research and policy the authors thank elenette prado, department of emergency medicine, for providing secretarial assistance. key: cord-339245-02gr4mfy authors: ehni, jordan; moss, marie; herbison, ilka; anderson, trevisia; siju, jemilat; dugan, kevin; resnick, garrison; weisburd, shari; brown, sean; alexander, kinta; camins, bernard; javaid, waleed title: utilizing technology to enhance screening for highly infectious diseases date: 2020-07-09 journal: am j infect control doi: 10.1016/j.ajic.2020.07.008 sha: doc_id: 339245 cord_uid: 02gr4mfy • digital survey applications can be used to create highly infectious disease screening tools; • digital screening tools simplify patient screening for non-clinical staff at facility entrances; • digital screening tools can be monitored remotely to assist with compliance. quick identification and isolation of patients with highly infectious diseases is extremely important in healthcare settings today. this study focused on the creation of a digital screening tool using a free and publicly available digital survey application to screen patients during a measles outbreak in new york city. the results indicate that digital tools are an effective alternative to paper tools due to their ease of use and remote compliance monitoring capabilities.  digital survey applications can be used to create highly infectious disease screening tools  digital screening tools simplify patient screening for non-clinical staff at facility entrances  digital screening tools can be monitored remotely to assist with compliance quick identification and isolation of patients with highly infectious diseases is extremely important in healthcare settings today. this study focused on the creation of a digital screening tool using a free and publicly available digital survey application to screen patients during a measles outbreak in new york city. the results indicate that digital tools are an effective alternative to paper tools due to their ease of use and remote compliance monitoring capabilities. key words: infection prevention; patient screening; surveillance; highly infectious diseases; measles the three-pronged approach of identify, isolate, and inform (3i) has become a standard algorithm used in hospital settings for the quick identification and management of patients with a potential highly infectious disease. initially developed during the ebola crisis, these actions taken during the first few minutes of a patient encounter have since been used and adapted for new and re-emerging diseases such as measles and mers. 1, 2, 3 with the recent emergence of covid-19, the quick and effective identification of patients with highly infectious diseases is of great importance for healthcare facilities today. 4 this study specifically focuses on enhanced patient screening performed for measles. measles is characterized by rash, fever, cough, coryza and conjunctivitis. it is especially dangerous for unvaccinated babies and young children. 5 from september 2018 to august 2019, new york city experienced a measles outbreak in which 649 cases were identified. 6 during the peak of this outbreak in april 2019, the new york department of health emphasized that hospitals should perform enhanced screening to quickly identify and isolate patients with measles. in order to comply with this request, the infection prevention department within a large health system partnered with several other hospital departments to design and implement a digital measles screening tool. a screening tool was created using a free and publicly available digital survey application to identify patients at risk for having measles. the tool was administered by healthcare personnel to patients near healthcare facility entrances, and it asked questions about measles symptoms, vaccination history, exposure history, and residence in high risk locations ( figure 1 ). no identifying information of the patients was entered into the tool. the tool followed an automated question algorithm that led to one of two outcomes: placing a surgical mask on the patient and immediately informing clinical staff to perform a further risk assessment; or allowing the patient to proceed to their visit. security personnel and other front line staff were provided with tablets or computers and educated on how to use the tool. infection prevention staff routinely used the remote monitoring features of the digital application to electronically monitor use of the tool, and provided feedback over the three month enhanced screening time period to promote compliance. data was exported from the digital application for later analysis. approximately 59,435 patients were surveyed using the digital measles screening tool from 4/25/19 through 8/4/2019. of these patients, 91 (0.15%) flagged as high risk and required further evaluation by clinical staff to rule out measles ( figure 2 ). none of these 91 patients were later diagnosed with measles. no cases of confirmed measles were reported at the screening sites during the intervention time period. the large number of survey submissions received during the intervention time period indicated that healthcare personnel were successfully able to use the digital measles tool to quickly screen patients at healthcare facility entrances. of the large number of patients screened, only a small percentage (0.15%) were flagged as a risk for measles. the majority (65.9%) of these flagged patients had a fever and a rash ( figure 2 ). the small number of flagged patients indicated that the tool was not overly sensitive, which could have risked overwhelming staff and causing a traffic jam at the healthcare facility entrances. compared to paper tools and flowcharts traditionally used for patient screening, the digital tool created in this intervention proved to be simpler for staff to use due to the automated question algorithm function used in the digital survey application. 2,3 while some electronic medical records (emrs) have decision support tools available for patient screening, these emr tools can be expensive and often only accessible by clinical staff located away from healthcare facility entrances. 4 the easy to use nature of free digital survey applications allows any healthcare personnel (security, concierges, etc.) located at the first point of entry to screen patients and quickly isolate them before they enter into the facility or a waiting room. a few challenges were identified in implementation of the digital survey intervention. the first challenge was receiving buy-in from non-clinical staff being asked to implement the digital tool. additionally, these staff persons could intermittently be pulled away from patient screening to complete more urgent tasks, such as a security concern. these challenges were partly overcome by working together with management to regularly reinforce with front-line staff the benefits of patient screening. additionally, the remote monitoring capabilities of the digital tool allowed for intervention with staff when large time gaps were noted between survey submissions. the results of the intervention indicate that digital survey applications are effective alternatives to other infectious disease screening methods due to their ease of use by non-clinical staff working near healthcare facility entrances, and their remote compliance monitoring capabilities. digital survey applications offer promise for the early identification and isolation of patients entering into healthcare facilities with highly infectious diseases, such as covid-19. inform: emergency department evaluation and management for patients under investigation (puis) for ebola virus disease (evd) identify-isolate-inform: a tool for initial detection and management of measles patients in the emergency department identify-isolate-inform: a modified tool for initial detection and management of middle east respiratory syndrome patients in the emergency department can you catch it? lessons learned and modification of ed triage symptom and travel screening strategy signs and symptoms health topics: measles. nyc department of health and hygiene key: cord-308546-wlnbpgz7 authors: meyer, julien; nippak, pria; cumming, aisling title: an evaluation of cleaning practices at a teaching hospital date: 2020-06-26 journal: am j infect control doi: 10.1016/j.ajic.2020.06.187 sha: doc_id: 308546 cord_uid: wlnbpgz7 background: the covid-19 outbreak has highlighted the role of hospital-acquired infections in spreading epidemics. adequately cleaning surfaces in patient rooms is an essential part of this fight to reduce the spread. traditional audits, however, are insufficient. this study assesses surface cleaning practices using uv marker technology and the extent to which this technology can help improve cleaning audits and practices. methods: 144 audits (1,235 surfaces) were retrieved. uv marker cleaning audits conducted at a major teaching hospital in 2018 after implementing a new cleaning protocol. in addition, semi-structured interviews were conducted with cleaning staff and supervisors. results: on average, 63% of surfaces were appropriately cleaned. toilet handles (80%) and toilet seats underside (83%) scored highest while main room sink fixtures (54%), light switch (55%) and bedrails (56%) scored lowest. training, staffing and time constraints may play a role in low cleaning rates. discussion: the high-touch patient surfaces in the bedroom remain neglected and a potential source of infections. uv marker audits provided an objective measure of cleaning practices that managers and staff were unaware of. conclusion: uv markers audits can play a key role in revealing deficiencies in cleaning practices and help in raising awareness of these deficiencies and improving cleaning practices. according to the who, hospital acquired infections account for 7% of all infections in developed countries and 10% in developing countries 1 . several outbreaks within long term care facilities and acute care facilities have been reported across canada from covid-19 and many were reported in acute care facilities during the sars epidemic [2] [3] [4] . the recent outbreak of covid-19 has caused many countries to go to extreme measures of setting up dedicated healthcare facilities as a containment measure, which clearly highlights the continuous importance of managing nosocomial infections to control epidemics 5 . frequent systematic cleaning and disinfecting practices (cdp) are key in controlling the spread of infection 6 within in-patient settings, since pathogens can persist on surfaces for several weeks if left uncleaned [7] [8] [9] . technological advancements have resulted in new cleaning and disinfecting tools and processes to improve the effectiveness of cdp to support infection control 10, 11 but cleaning standards and best practices are useful only if they are actually followed. despite its importance, environmental cleaning and disinfecting remains inadequate in hospitals 12, 13 . a 2008 study across 23 acute care hospitals across the usa showed that only 49% of 14 high risk surfaces (33% chance of contamination) were appropriately cleaned and disinfected. 14 it remains unclear whether these rates are improving. one of the challenges to improve cdp is to obtain feedback on actual practices. traditionally, cdp are monitored through visual assessment audits, which are limited by the invisible nature of the cleaning outcome. uv marker technology is an innovation that measures whether physical wiping of surfaces occurred to the necessary level to result in removal of the invisible gel 15 . the visual aid of uv marker auditing is helpful in identifying cdp efficacy, identifying where correction is needed and providing the information to fuel staff training on effective cleaning procedures [15] [16] [17] . in this paper, we leverage uv marker technology to assess environmental cleaning at a large academic teaching hospital in canada. the objectives are firstly to determine the extent to which surface cleaning meets cleaning standards and secondly to assess how uv markers can improve cleaning audits and cdp. this study analyzes the retrospective quantitative data from cleaning audits conducted at a major acute care and teaching hospital in canada. in this section, we describe the empirical setting and its cdp before describing our data collection and our analysis methodology. the infection control department of that hospital trained all cleaning staff on provincial standards of cdp and on the application of a standard operating procedure for cleaning (sop), which details appropriate cleaning methods and is attached to all cleaning carts. notably, the sop: a) contains a checklist of high-touch surfaces that must be cleaned and disinfected along with diagrams to highlight high-touch surfaces in patient rooms and washrooms (refer to appendix a for the list of high-touch surfaces to clean and disinfect and to appendix b for a visual illustration). b) requires that cleaners apply a sporicidal agent, virox 5, to wet environmental surfaces. virox 5 is a 7% accelerated hydrogen peroxide concentrate solution. c) requires that surface should remain wet for 10 minutes, in conformance with virox 5 manufacturer recommendations and public health standards d) after the minimum time period, the cleaner returns to repeat the same process, allowing the second application of the agent to sit for another ten minutes. in practice, by the time the employees have cleaned all high touch areas, 10 minutes would have elapsed and they would commence the second cleaning in the same succession of steps, alternatively, cleaners would go to another room and then come back for the second cleaning. to ensure the double cleaning, the cleaner signs off on a checklist outside of the patient room and returns it to the supervisor to verify that the double cleaning procedure was followed e) requires the use of microfiber cloths for all cdp in the hospital. to track compliance, the environmental cleaning services implemented a uv marker audit system. an internal auditor applied a uv visible marker to several identified frequently touched surfaces in patient rooms (refer to appendix c for details on the auditing methodology). the high touch surfaces reflected in the sop and the provincial standards are five surfaces in the bathroom and five within the patient room (six if a patient-room had a sink). these marked surfaces were then evaluated between 48 hours to up to 144 hours later (6 days), after the markers were set. this long interval between uv marker application and auditing was decided to minimize the chance that no cleaners would have gone into a room before the audit was performed. this conservative decision was made considering that based on admissions and priorities, a shift may completely skip a room. if there was visible agitation or removal of the visual marker, the surface was considered "marker not visible"; any remaining intact marker is a fail (see appendix c for illustrations). the uv marker cannot rub off by mere contact that a patient may have with the surface. auditing staff tested and confirmed that it takes moisture and repeated force to remove the uv marker. the auditor then entered results into an electronic auditing tool via a tablet. see appendix e for a sample room audit. information about the audits also included the location (unit and department) and whether they were a standard or discharge cleaning. discharge cleaning requires an enhanced cleaning protocol after a patient is discharged. audits were extracted from the electronic auditing tool. auditing results from an initial observation period were excluded as the observer present in the room added a confounding variable to the results. data were collected over a two-month period (july and august 2018) between two departments, surgery and oncology (96 beds) and the urgent critical care/medicine department (ucc, 104 beds). the total audit sample size consisted of 144 audits and 1,235 surface measurements obtained. see table 1 for a summary of the distribution of audits. to complement this data, one of the authors interviewed the cleaning staff and their supervisors to determine their knowledge of the environmental auditing program and cleaning methods. cleaning rates were calculated by dividing the count of surfaces marked "marker not visible" by the total number of surfaces measured. average cleaning pass rates were broken down by surface and department. two binomial tests were performed to assess whether the differences in pass rates between surgery and oncology and ucc were statistically significant and whether the differences between discharge cleaning and standard cleaning were statistically significant. audit findings table 2 summarizes the cleaning rates, broken down by surface, by department and between discharge and standard cleanings. overall, 63% of surfaces were marked with "marker not visible" (i.e., have been cleaned) for all audits conducted on all surfaces. the two surfaces with the highest score for "marker not visible" were the toilet handle (80%) and the underside of the toilet seat (83%). in contrast, bed rails (56%) and bed/stretcher bedrails (56%) scored lowest. (1,235) the pass rates were 65% in the ucc department and 62% in the surgery and oncology department. the p-value of the binomial test was .066, suggesting that the null hypothesis could not be excluded and that there was no statistically significant difference in cleaning rates between the two departments' cleaning rates. the data also showed a 67% pass rate for discharge cleaning versus a 62% for standard cleaning. the p-value of the binomial test was .027, suggesting that discharge cleaning had a significantly higher pass rate than standard cleanings. staff indicated knowledge of the practices and procedures for effective cleaning and disinfecting and understood the importance of discharge cleaning. however, they noted that time constraints and workload were often a barrier to effective cdp. specifically, they pointed out that the pressure of admitting new patients to a room sometimes negatively impacted discharge cleanings (even though they recognized that they should to be more thorough than standard cleaning). staff also provided feedback on the auditing process, suggesting approaches for improving the electronic auditing tool to reflect auditor information, discharge versus standard cleaning and other factors outside of the scope of this study. the results indicate relatively low environmental auditing score results with only 63% of surfaces cleaned appropriately, well below the department or hospital standards of 80% 18 . these low rates are compounded by the 2 to 6 days delay between uv marker application and the audit, a time period during which several cleanings may have happened. this means that the rate of single room cleanings being appropriate may be significantly lower and further studies should audit single cleanings. these findings highlight the need for improved cleaning standards, particularly as both hospitals and long term care facilities continue to treat covid-19 patients and need to reduce the risk of hospital acquired cases. among high-touch surfaces, also associated with a high risk of surface contamination, 19 ,20 toilet surfaces (83% for toilet seat and 80% for toilet handles) were reassuringly above the 80% threshold, but bed rails (56%) and bedside tables (57%) were concerningly low. standard room cleanings are done with the permission of the patient, and patients allowing the uv marker to be placed would be likely to allow it to be cleaned as well. however, in some instances, bedridden patients may have rejected cleaning and disinfecting bed rails and bedside tables or cleaners may have been reluctant to disturb patients.. these largely uncleaned high touch surfaces in a patients' room, however, can be a reservoir for pathogens and transmission to other patients 20, 21 . the study results suggest that there is a need to increase the focus of cdp, most importantly to these high touch surfaces close to the bed where patients spend a lot of their time, which is consistent with other studies 22 . specific protocols may have to be designed for bedrails and bedside tables in case patients are in bed and/or sleeping. discharge cleaning is far more detailed in comparison to standard cleaning and it requires a deep cleaning of all patient bed surfaces, the mattress, and all surrounding surfaces and fixtures 12 . despite this emphasis, actual discharge cleaning on common surfaces was below standards and barely above standard cleaning. an insufficiently cleaned room poses a serious risk to an incoming patient given that pathogens can remain on uncleaned surfaces for several weeks 23 . these findings align with other similar studies of uv marker auditing 24 and suggest the usefulness of such audits. the cleaning staff and supervisors of the site were unaware that their cdp were falling so far below provincial standards. these findings confirm that uv marker auditing can provide reliable feedback and novel insights into actual cleaning practices 25-27 , which are difficult to objectively determine with the naked eye. these elements are essential to improve staff awareness, knowledge, understanding and cleaning practices and for supervisors to effectively monitor cleaning quality and performance 25 . insufficient resources often contribute to infrequent or incomplete cleaning within the hospital. 28 objective audit results may help highlight the need for sufficient resources to yield quality cdp standards. hospitals should take steps to ensure that the quality of cdp remains a priority over rapidity, especially at discharge when rooms need to be made available to new patients. while, patient turnover is important, controlling the spread of hospital acquired infections is paramount, particularly since the onset of the covid-19 outbreak. an approach combining continuous uv marker auditing to identify areas for cleaning improvement and consistent feedback to staff on the audit results, combined with tailored training to address any noted cleaning deficiencies, together can increase cdp compliance. 17 the more timely the feedback is provided to staff, the more quickly auditing results can improve, thereby increasing cdp compliance. 17 these results need to be interpreted with caution. first, the sample size was limited. for instance, patient-room sink cleaning was only available on a sample of 6 audits because of the lack of rooms with a patient sink. likewise, the sample for discharge cleaning was only 15 rooms. second, there were variations in the underlying processes being observed. while all staff had some kind of knowledge about the audits, some staff were unaware if they had been audited, while others knew they had been audited. moreover, there were variations in the application of the electronic auditing tool, such as the time interval elapsed between marker placement and audit. there were also variations in room configurations, some having multiple beds, multiple rails per bed, additional sinks or hand sanitizers, which were added to the total count of surfaces measured. third, the surface marker in this study had to only be disturbed to be measured as a 'marker not visible' instead of being completely removed as suggested in some guidelines. 18 this study suggests that cdp in teaching hospitals may not be up to the standards required to contain pandemics such as covid-19. it also suggests that uv markers can play a key role in a systematic auditing program to measure effective cleaning of patient rooms. this auditing technique coupled with rapid feedback and training to cleaners can lead to increased awareness and improvement in cleaning practices and outcomes. this approach can best be achieved as part of a continuous improvement effort rather than as a reaction to emergencies and outbreaks. nosocomial infections: epidemiology, prevention, control and surveillance long-term psychological and occupational effects of providing hospital healthcare during sars outbreak. emerging infectious diseases middle east respiratory syndrome investigation of a nosocomial outbreak of severe acute respiratory syndrome (sars) in toronto shelter hospital mode: how to prevent novel coronavirus infection 2019 (covid-19) hospital-acquired infection? infection control & hospital epidemiology role of hospital surfaces in the transmission of emerging health care-associated pathogens: norovirus, clostridium difficile, and acinetobacter species how long do nosocomial pathogens persist on inanimate surfaces? a systematic review controlling hospital-acquired infection: focus on the role of the environment and new technologies for decontamination bacterial contamination of inanimate surfaces and equipment in the intensive care unit four steps to clean hospitals: look, plan, clean and dry reducing clostridium difficile in the inpatient setting: a systematic review of the adherence to and effectiveness of c. difficile prevention bundles. infection control & hospital epidemiology surface cleaning effectiveness in a walk-in emergency care unit: influence of a multifaceted intervention modern technologies for improving cleaning and disinfection of environmental surfaces in hospitals identifying opportunities to enhance environmental cleaning in 23 acute care hospitals researching effective approaches to cleaning in hospitals: protocol of the reach study, a multi-site stepped-wedge randomised trial evaluating and operationalizing an environmental auditing program: a pilot study continuing performance feedback and use of the ultraviolet visible marker to assess cleaning compliance in the healthcare environment improved eradication of clostridium difficile spores from toilets of hospitalized patients using an accelerated hydrogen peroxide as the cleaning agent the role of environmental contamination in the transmission of nosocomial pathogens and healthcare-associated infections risk of acquiring multidrugresistant gram-negative bacilli from prior room occupants in the intensive care unit. clinical microbiology and infection reducing health care-associated infections by implementing separated environmental cleaning management measures by using disposable wipes of four colors guidelines for prevention of hospital acquired infections. indian journal of critical care medicine: peer-reviewed, official publication of indian society of critical care medicine how to eradicate clostridium difficile from the environment the role of ultraviolet marker assessments in demonstrating cleaning efficacy evaluating and operationalizing an environmental auditing program: a pilot study continuing performance feedback and use of the ultraviolet visible marker to assess cleaning compliance in the healthcare environment environmental cleaning resources and activities in canadian acute care hospitals identification of affective state change in adults with aphasia using speech acoustics a survey of environmental service workers' knowledge and opinions regarding environmental cleaning key: cord-290961-wbdfcaup authors: khan, dr shahrukh; saultry, ms bridey; adams, dr scott; kouzani, dr abbas z.; decker, ms kelly; digby, dr robin; bucknall, alfred deakin professor tracey title: comparative accuracy testing of non-contact infrared thermometers and temporal artery thermometers in an adult hospital setting date: 2020-10-02 journal: am j infect control doi: 10.1016/j.ajic.2020.09.012 sha: doc_id: 290961 cord_uid: wbdfcaup background: ncit are non-invasive devices for fever screening in children. however, evidence of their accuracy for fever screening in adults is lacking. this study aimed to compare the accuracy of non-contact infrared thermometers (ncit) with temporal artery thermometers (tat) in an adult hospital. methods: a prospective observational study was conducted on a convenience sample of non-infectious inpatients in two australian hospitals. ncit and tat devices were used to collect body temperature recordings. participant characteristics included age, gender, skin colour, highest temperature and antipyretic medications recorded in last 24-hours. results: in 265 patients, a mean difference of ±0.26°c was recorded between the ncit (36.64°c) and the reference tat (36.90°c) temperature devices. bland-altman analysis showed that ncit and tat temperatures were closely aligned at temperatures <37.5°c, but not at temperatures >37.5°c. ncit had low sensitivity (16.13%) at temperatures ≥37.5°c. an auroc score of 0.67 (sd 0.05) demonstrated poor accuracy of the ncit device at temperatures ≥37.5°c. conclusion: this is the first study to compare accuracy of ncit thermometers to tat in adult patients. although mass fever screening is currently underway using ncit, these results indicate that the ncit may not be the most accurate device for fever mass screening during a pandemic. body temperature is a vital sign that is regularly measured to assess the status of a patients' health, facilitate diagnosis and target treatments in a hospital setting. normal body temperatures range from 36.5°c to 37.5°c 1 . upward deviation from this range reflects a fever and may require treatment. healthcare professionals must use the most accurate and precise measurement devices available to reproduce stable results reflecting core body temperature. the gold standard method of determining core body temperature measures blood temperature 2, 3 . other invasive methods measure core body temperature at various sites including the oesophagus, the nasopharynx or the urinary bladder 4, 5 . although these methods provide accurate representation of core body temperature, their invasive nature limits their application in a wide range of patients during outbreak or pandemic situations such as covid-19. thus, new technological tools that avoid contact and prevent the transmission and spread of viruses are emerging. the world health organisation (who) instigated public health measures including body temperature screening for rapid identification of potential coronavirus cases and infection prevention 6, 7 . not surprisingly, a quick, non-contact, reliable, cost-efficient and easy to use approach for temperature assessment is a pressing need for screening individuals in the current covid-19 era. one potential method is an indirect estimate of core temperature measurement using non-contact infrared thermometers (ncits). the ncit is a non-contact, rapid and portable body temperature measuring tool. measurements are taken from the frontal bone or the temporal artery. the ncit does not require sterilisation between individuals, therefore making it a strong contender for massscreening in pandemic situations. the ncits have been used in a wide-range of settings where the temperature of an object needs to be measured without touching it. they infer temperature by capturing the thermal radiation emitted from a focussed spot, concentrating it onto a sensing element, and converting it to an electronic signal. this signal is then digitally processed, and the temperature value is presented to the user. the conversion between thermal radiations to an electrical signal was originally described by macedonio melloni in the early 1800s through the discovery of the thermopile. since melloni's original discovery, vast improvements in fabrication and measurement processes have enabled modern devices to provide highly accurate and precise non-contact temperature measurement capabilities in a handheld unit. however, similar to many other thermometers, these devices are highly reliant on correct operator use in order to obtain accurate results. a key consideration is the distance-to-spot ratio, as the size of the area measured is directly related to the distance to the operator. therefore, the medical use of the ncits always recommends a specific distance between the device and the point being measured to ensure accurate results. if this distance is not fulfilled, it is impossible to guarantee that the measurements reported from the device are actual readings from the required location. insufficient evidence exist that compares the measurement accuracy and precision of the ncits with gold standard core temperature measurement devices in adults. most studies conducted to date, determine the accuracy and reliability of the ncits in children, and these studies have reported conflicting results. in children, a 0.2-0.4°c mean difference in body temperatures at or above 37.5°c was reported between the ncit temperature when measured at forehead as compared to the core temperature measurements conducted using temporal artery thermometers (tats) 8, 9 . also in paediatric populations, studies have compared the ncits with alternate devices including axillary digital thermometers 8-10 , tympanic artery thermometers 8, 11, 12 , and rectal thermometers 12 . thus, in the current pandemic, this degree of error could result in inappropriate referrals for treatment, undetected infection transmissions across healthcare organisations and associated impacts on patient safety and clinical decisionmaking. studies comparing the correlation and differences in body temperature measured using the ncits and other temperature measurement methods in adults are scarce. thus, it is necessary to collect scientific evidence using robust research methods on the accuracy of the ncits when used in adult populations. therefore, this study compared the accuracy of the ncit with the tat in hospitalised adults. characteristics of the patients' age, gender, skin colour, anti-pyretic medication use and highest temperature in the last 24 hours are assessed to determine their influence on body temperature measurement. a prospective observational study design was used to determine the accuracy of temperature measurement of the ncit in relation to the tat. this study was administered at two metropolitan hospitals in melbourne, australia. the first, a tertiary hospital that has approximately 500 beds and provides comprehensive healthcare services in the state of victoria, australia. it has the busiest emergency and trauma centre in australia, one of the largest intensive care units in australia, and provides 14 statewide services. the second hospital has approximately 140 beds and provides state-wide rehabilitation services including brain injury rehabilitation, neurological rehabilitation, spinal rehabilitation, aged care, and care for amputee patients. the study used a convenience-sampling method for recruitment of participants. all hospitals' inpatients were invited to participate in this study. a registered nurse explained the study aims and requirements of participation prior to obtaining verbal consent and data collection. patients aged 16 years and older who were willing to have their temperature taken were eligible to participate. patients in covid-19 infection screening clinics, the emergency department, hospital in the home, radiology, outpatients and wards with diagnosed covid-19 cases were excluded. patients in isolation for any other reason were also excluded. sample size was calculated using the australian bureau of statistics sample size estimator 14 . using tay et al.'s study as a reference (n=430 participants, 7.9% fever reports), a sample size of 265 participants, were required at a prevalence rate of 5% febrile cases in metropolitan hospitals' patients, and a standard error of 0.01 15 . two temperature measuring devices were used. the ncit (cocoon-nc9900) is a non-contact battery operated temperature measurement device that records body temperature or ambient temperature. it has a built-in infrared laser pointer, and records temperature in two different units (celsius and fahrenheit). ncit is a factory-calibrated instrument that automatically calibrates in first 15 seconds when the device is switched on for use. the tat (exergen tat 5000) also uses infrared technology to record temperature. temperature is measured by gently moving the tat across the forehead, and includes a momentary touch of the probe to the neck area behind the ear lobe, to account for any cooling of the forehead as a result of diaphoresis. the temperature of the skin surface (over the temporal artery) is measured used arterial heat balance technology (ahb™). the tat takes rapid sequential readings at up to 1000 measurements per second, and reports the highest temperature detected (peak) during the measurement course. the calibration of the tat is established by automation process through which the tat instrument automatically self-calibrates each time the instrument is turned on. the biomedical engineering team at the tertiary hospital conducts performance testing annually using the manufacturer instructions to assess calibration of the instrument. the demographic variables recorded were age, gender and skin colour. these variables were recorded on a case report form for each individual. the temperature using both devices was also recorded for each individual and information from the patient's electronic medical record: highest temperature in last 24 hours, and antipyretic medications taken in last 24 hours. prior to data collection, the nurse manager or resource nurse identified any patients or areas who were infectious to exclude them from the study. following patient consent, body temperatures were taken using the standard tat and the ncit on the forehead. the registered nurse taking the temperature followed the manufacturer's instructions for the use of tat and ncit. she reviewed the manufacturer's instructions and was observed to follow the correct technique prior to commencing the data collection. personal protection equipment of masks and gloves were worn by the data collector. the temperature evaluation was performed during the hours of 8:00 am to 6:00 pm for a period of four days. the stata statistical software package (version 16) was used for statistical analysis 16 . for all tests, the level of significance was set at 0.05. frequency distributions and mean (standard deviations) were calculated for characteristics of age, gender, skin colour, highest temperature and the anti-pyretic medication used in the last 24 hours, and body temperature recordings using the two devices. an independent sample t-test was used to calculate the mean difference between the body temperature recordings of the tat and the ncit. box plots were constructed to determine the differences in ncit body temperature amongst tat fever and non-fever groups. bland altman analysis was plotted, with mean difference of the tat and the ncit on the y-axis and the tat temperatures on the x-axis. a bivariate analysis using the chi-square test was performed to determine the association between the patients' characteristics and body temperature measurements. the area under the receiver operating characteristics (auroc) was calculated. for this study auroc estimated the accuracy of ncit ability to separate febrile and non-febrile patients. an auroc value of 1 indicates the tool is strong; whereas an area of 0.5 or less indicates that the test fails to differentiate. sensitivity and specificity score calculations were made to test the capability of ncit to correctly identify patients with fever and without fever, respectively. strict confidentiality of information relating to patients was maintained to protect patient identity, and to ensure no disclosure of private information. the data collected for this study was stored on a password protected redcap database in a secure server with access available only the investigator team. the study was approved as an evaluation project as it did not meet the trigger for the ethical review as stated in the national health and medical research council ethical considerations in quality assurance and evaluation (2014) 13 . the manuscript was reviewed by the executive director for nursing services and approved for publication. two hundred and sixty-five patients, aged 16 years and older were enrolled in this study. table 1 shows the characteristics of participants. the mean age of participants was 58.77 years (sd 5.04). almost 51% participants in this survey were 60 years and older and the rest 49% participants were equally distributed amongst age groups of <30 years, 30-40 years, 40-50 years and 60-70 years respectively. there were 18.86% participants of 70-78 years, 15.84% of 80-90 years and 3.39% of 90+ years. over 59% of the sampled population were males. more than 91% of the participants had light skin colour. the mean highest temperature measured using the reference tat in the last 24 hours was 36.98°c (sd 0.12). almost 66% of participants had taken an anti-pyretic medication in last 24 hours, the majority had taken a mean dose of 1gm of paracetamol. table 2 shows the comparison between the ncit and the tat mean temperatures and mean differences. the mean temperature measured using the tat and the ncit were 36.98°c and 36.64°c, respectively. temperatures recorded using the ncit (0.26, p<0.001) had a significant mean difference as compared to the reference temperature using the tat. table 2 . mean temperature and mean temperature differences found using the tat, the ncit mean a bland-altman analysis compared the ncit with the reference tat device ( figure 2 ). the margin of error was narrow. the average mean difference (bias) for comparison the ncit measurements were closely clustered to that of the tat body temperatures. the difference between the ncit and the tat was more dispersed at temperatures above 37.5°c (0.50, 95% confidence interval 0.5-1.0). however, this result should be interpreted with caution due to low numbers of febrile cases (tat febrile group n=31; ncit febrile group n=7) found in the studied cohort. ncits are increasingly used for mass temperature screening due to its non-contact, rapid processing and hygiene maintenance attributes. yet there is little evidence analysing the accuracy of the ncit for use in adults. to address this gap, this study compared the accuracy of the ncit to the tat, a non -invasive infrared thermometer widely used in hospitals. four key findings were found in this research. first, the ncit's mean body temperature measurement (36.64°c) was in agreement with that of the tat's (36.90°c). a mean difference of ±0.26°c was recorded between the ncit and the reference tat. second, the bland-altman analysis showed that temperatures measured using the ncit and the tat were closely aligned at temperatures below 37.5°c but at temperatures >37.5°c, the mean differences widened considerably. third, an auroc score of 0.67 (sd 0.05) demonstrates poor accuracy of the ncit device at temperatures ≥37.5°c. fourth, patient characteristics were associated with significant mean differences in temperature. paediatric studies have suggested that the ncit is an accurate and reliable device based on its sensitivity and specificity scores, and lower mean difference when compared to alternate temperature measuring devices 13, 17 18 . the differences in diagnostic accuracy in ours and previous studies may result from differing patient characteristics, device attributes and environmental factors (e.g. ambient temperature). strict attention to the standard operating procedures based on user guidelines is required to be followed for accurate measurement of temperature using ncit devices 19 . if standard operating procedures are not adhered to and incorrectly executed, then non-accurate results may occur 19 . in our study, the same rn collected the temperatures and strictly attended to the standard operating procedures for each patient measured. other studies patient characteristics of gender and skin colour were significantly associated with the mean difference in temperatures. higher mean temperature differences for females compared to males is consistent with the literature that reports females have greater thermal responses to exogenous and endogenous heat load/loss. a larger ratio of body surface to body mass, greater subcutaneous fat, and lower exercise capacity are factors that influence female temperature regulation 20 . hormonal modulation during the menstrual cycle may also modify thermoregulation in women 20 . in the current study, participants with light skin colour had a higher mean difference in body temperature as compared to participants with medium and dark skin colour. to the authors' knowledge, this is the first study that has compared the temperature differences based on skin colour. there is a level of subjectivity deciding on skin tone so we chose to group into two groups. however there were small numbers in the sample so the results must be interpreted cautiously. other factors, not analysed in this study, may also influence body temperature discrepancies between the ncit and the tat. these factors include patient-and environmental-related factors. we did not attempt to determine some patient-related factors such as skin thickness, blood flow under the skin, metabolic rate, cardiac output, hormonal levels. other patient characteristics, such as forehead perspiration 13 and anti-pyretic medication taken, may influence the ncit measurements. other environmental factors that could lead to false readings includes sub-optimal training of operators, inappropriate positioning of the thermometer, and uncontrolled temperature within the rooms. the ambient temperature of each ward was not recorded in this study. however, pre-operational training by the research nurses in regards to the device use and device cleaning, were undertaken to follow the device manufacturer instructions. this is the first study to compare accuracy of ncit to a reference device tat in adult hospitalised patients. although mass fever screening is currently underway using ncit, these results indicate that the ncit may not be the safest device for mass fever screening in adults if used in isolation during a pandemic. it should be noted that fever screening is often conducted in less controlled conditions than those presented in this study, which may result in further decreased accuracy than our findings. additional research is required to compare its accuracy and precision to other invasive and non-invasive core body temperature testing methods. hypothermia: prevention and management in adults having surgery. nice clinical guideline simplified and highly accurate core temperature measurements core body temperature measurement: a comparison of axilla, tympanic membrane and pulmonary artery blood temperature accuracy of digital tympanic, oral, axillary, and rectal thermometers compared with standard rectal mercury thermometers comparison of esophageal, rectal, axillary, bladder, tympanic, and pulmonary artery temperatures in children novel coronavirus ( 2019-ncov). 2020. world health organization covid-19): information and advice about coronavirus (covid-19) -symptoms, travel and what to do to reduce the risk of infection department of health and human services victoria clinical accuracy of tympanic thermometer and noncontact infrared skin thermometer in pediatric practice: an alternative for axillary digital thermometer use of noncontact infrared thermography to measure temperature in children in a triage room digital axillary and non-contact infrared thermometers for children comparison of infrared tympanic thermometer with non-contact infrared thermometer. / temassz kzlötesi termometre ile timpanik kzlötesi termometre karslastrmas accuracy of tympanic and infrared skin thermometers in children sample size calculator comparison of infrared thermal detection systems for mass fever screening in a tropical healthcare setting performance of non-contact infrared thermometer for detecting febrile children in hospital and ambulatory settings kaciuba-uscilko h and grucza r. gender differences in thermoregulation to the authors' knowledge, this is the first study that determined the accuracy of the ncit in comparison to the tat in adult inpatient hospital wards. the study followed strict protocol and infection control guidelines. there were several limitations for this study. first, a convenience sampling method was used for recruitment of participants in two hospitals.although this is a simple, cost effective and easy to use method, the sample recruited using this method may not representative of the population. second, repeated measures were not recorded to check precision of the ncit. third, the number of febrile cases (≥37.5°c) were limited to 31(11.7%) cases only. the ncit is a fast, non-invasive, non-touch, hygienic device. ncit temperature device training is required to increase the accuracy of the measurements.however, variable levels of accuracy in paediatric and adult populations highlighted the need for further research, particularly to validate the use in adults. in this instance, a larger sample size, use of a random sampling method, and repeated measurement of temperatures using ncit and multiple reference devices is required. furthermore, the response of ncit devices to patient and environment factors such as patient physical characteristics, physical exercise and variable ambient temperatures needs further study. given the low sensitivity for temperatures over 37.5°c it may be preferable to use a direct temperature measurement device for temperatures greater than 37.5°c to check accuracy in health care settings. nurses frequently have various temperature measurement options to use in clinical settings, this article offers a comparison of two different types that both indirectly rely on skin temperature measurement. this study provides health professionals with information on the reliability of the ncit and cautions them about the low sensitivity for temperatures over 37.5°c. key: cord-328116-jnll9g6g authors: malhotra, sanchi; wlodarczyk, jordan; kuo, christopher; ngo, catherine; glucoft, marisa; sumulong, ivan; smit, michael a.; bender, jeffrey m. title: shining a light on the pathogenicity of health care providers' mobile phones: use of a novel ultraviolet-c wave disinfection device date: 2020-06-05 journal: am j infect control doi: 10.1016/j.ajic.2020.05.040 sha: doc_id: 328116 cord_uid: jnll9g6g background: mobile phones are known to carry pathogenic bacteria and viruses on their surfaces, posing a risk to healthcare providers (hcps) and hospital infection prevention efforts. we utilize an ultraviolet-c (uv-c) device to provide an effective method for mobile phone disinfection and survey hcps about infection risk. methods: environmental swabs were used to culture hcps’ personal mobile phone surfaces. four cultures were obtained per phone: before and after the uv-c device's 30-second disinfecting cycle, at the beginning and end of a 12-hour shift. surveys were administered to participants preand post-study. results: total bacterial colony forming units (cfus) were reduced by 90.5% (p=0.006) after one uv-c disinfection cycle, and by 99.9% (p=0.004) after two cycles. total pathogenic bacterial cfus were decreased by 98.2% (p=0.038) after one and >99.99% (p=0.037) after two disinfection cycles. all survey respondents were willing to use the uv-c device daily to weekly, finding it convenient and beneficial. discussion: this novel uv-c disinfecting device is effective in reducing pathogenic bacteria on mobile phones. hcps would frequently use a phone disinfecting device to reduce infection risk. conclusions: in light of the ongoing coronavirus (covid-19) pandemic, a standardized approach to phone disinfection may be valuable in preventing healthcare-associated infections. -novel uv-c device found to significantly decrease total and pathogenic bacteria on mobile phones -uv-c phone disinfecting device is renewable, efficient and effective -uv-c device implementation in a hospital system would be desired by healthcare providers -healthcare providers felt their mobile phones were an important risk factor in infection transmission and that they would use this device daily to weekly -uv-c technology is shown to kill coronaviruses and implementation of this device could be impactful during pandemic abstract: background: mobile phones are known to carry pathogenic bacteria and viruses on their surfaces, posing a risk to healthcare providers (hcps) and hospital infection prevention efforts. we utilize an ultraviolet-c (uv-c) device to provide an effective method for mobile phone disinfection and survey hcps about infection risk. methods: environmental swabs were used to culture hcps' personal mobile phone surfaces. four cultures were obtained per phone: before and after the uv-c device's 30-second disinfecting cycle, at the beginning and end of a 12-hour shift. surveys were administered to participants pre-and post-study. results: total bacterial colony forming units (cfus) were reduced by 90.5% (p=0.006) after one uv-c disinfection cycle, and by 99.9% (p=0.004) after two cycles. total pathogenic bacterial cfus were decreased by 98.2% (p=0.038) after one and >99.99% (p=0.037) after two disinfection cycles. all survey respondents were willing to use the uv-c device daily to weekly, finding it convenient and beneficial. discussion: this novel uv-c disinfecting device is effective in reducing pathogenic bacteria on mobile phones. hcps would frequently use a phone disinfecting device to reduce infection risk. conclusions: in light of the ongoing coronavirus (covid-19) pandemic, a standardized approach to phone disinfection may be valuable in preventing healthcare-associated infections. keywords: uv-c device, disinfection, infection control, mobile phones, healthcare associated infections background: as we aspire to reduce the spread of infection in hospital systems, mobile phones are increasingly recognized as fomites and potential contributors to healthcare-associated infections (hais). previous studies have shown the presence of multiple bacteria associated with hais on healthcare providers' (hcps) mobile phones. 1-4 ten percent of phones have also been shown to carry viral pathogens such as influenza and respiratory syncytial virus. 5 more importantly, the pathogens found on mobile phones are similar to those found on hands. 3 therefore, the cleanliness of mobile phones may be an important contributor to hand hygiene and the prevention of hais. in previous studies only 13-37% of hcps claim to clean their phones regularly. 2, 5 germicidal wipes for handheld devices are currently available but are inconsistently used, can damage electronic screen, and are not renewable. although studies have recognized the colonization of pathogens on mobile phones and the need for disinfection, they do not offer a more efficacious solution 1-4, 6 . our study presents a novel and safe method of ultraviolet-c light (uv-c) mobile phone disinfection. uv-c is already commonly used and has demonstrated efficacy in the hospital setting for disinfecting of patient rooms, pharmacy cleanrooms, and operating rooms (ors). [7] [8] [9] uv-c light technology kills or inactivates methicillin-resistant staphylococcus aureus (mrsa), clostridioides difficile (c. diff) spores, and norovirus at the same effectiveness as hydrogen peroxide wipes. 10, 11 marra et al. also showed a statistically significant reduction of c. diff and vancomycin-resistant enterococcus (vre) infection rates with uv light technology. 12 when used on keyboards and computer mice, uv-c light led to a >99% reduction in bacteria, including those responsible for hais. 13 by implementing a uv-c mobile phone cleaning device in a hospital unit, we attempted to decrease the burden of overall bacteria and pathogens identified on hcps' mobile phones. we aim to decrease the risk of hais presented by mobile phones in a safe and effective manner without using valuable resources such as germicidal wipes or cleaning solutions. we hypothesize that this uv-c technology can be effective when used for mobile phones. we performed a prospective investigational study evaluating the use of a novel disinfection protocol for personal mobile communication devices in a healthcare setting. this study was reviewed and approved by the children's hospital los angeles institutional review board. we utilized a new uv-c device (phonesoap med + version 1, provo, ut), 14 to provide a more effective and convenient tool for the disinfection of mobile phones. the device is a handsfree box with 16 uv-c bulbs that encase the phone and uses a 30-second cleaning cycle. stepby-step instructions are displayed on the box (supplemental figure 1 ). 15 we evaluated both pediatric residents and nurses working a 12-hour shift on a pediatric medical/surgical unit. exclusion criteria included non-clinical staff, attending physicians, and physician subspecialists as their shift times were less regulated. environmental swabs were used to obtain bacterial cultures of the hcps' personal mobile phone surfaces. the mobile phones were labeled by number to ensure anonymity from the hcps. swabs were obtained at four time points. two swabs were collected per phone prior to a nursing or resident shift: before (premorning disinfection) and after (post-morning disinfection) the 30 second disinfection cycle. after being handled throughout a 12-hour shift by hcps during the course of patient care, the mobile phones were again swabbed twice: before (pre-night disinfection) and after (post-night disinfection) using the uv-c device. prior to obtaining swabs and placing each cell phone in the uv-c device for disinfection, study coordinators disinfected their hands with alcohol-based hand sanitizer and donned gloves. the entirety of the front screen of the mobile phone was swabbed at each time point. cultures were immediately labelled with the date and the pre/post disinfection cycle timing of the swab and were transported to a reference environmental microbiology laboratory. the mean bacterial colony forming units (cfu) count was calculated for each time period when cultures were obtained. analysis was done for both total bacterial counts and pathogenic bacterial counts. no susceptibility testing was done to differentiate mrsa or other resistant organisms. for statistical analysis, total bacterial count and pathogenic bacterial count were analyzed separately. the designation of a bacteria as 'pathogenic' was agreed upon by two infectious disease experts (mas, jmb). comparisons were made based on two complete data points. for assessment of statistical reductions or increases in bacterial load, spss statistical analysis software (version 26) was utilized to run paired t-test analyses. a 2-sided p value of 0.05 is considered statistically significant. in addition, paper questionnaires were administered at the beginning and end of the study day to elucidate attitudes towards mobile phone contamination and effectiveness of the novel uv-c device. a pre-study survey assessed hcps' perception of the risk of contaminated cell phones, current cleaning practices, and knowledge of uv-c light as a disinfecting mechanism. a post-study survey was also administered to determine the hcps' assessment of using the uv-c device and its' ease and effectiveness for future use. spss statistical analysis software (version 26) was utilized to run frequency tables for the survey. participants were verbally consented to participate, given the surveys, and handed an information sheet regarding the study. in compliance with irb guidelines no names or signatures were collected. we enrolled 21 nurses and 9 pediatric residents actively engaged in patient care on a contained pediatric medical/surgical unit. thirty mobile phones were tested with a total of 4 bacterial cultures each. one participant did not return for the second post-shift test, preventing the last two cultures of the protocol from being collected. this participant was still included to calculate the effectiveness of 1 disinfection cycle in the morning. this resulted in a total of 118 cultures collected during the study day. prior to the shift (morning), after one 30-second disinfection cycle, there was a 90.5% (p=0.006) reduction in the total bacterial cfu isolated from the mobile phones ( figure 1a) . the excluding the outliers, there was a 496% increase in bacterial load after a 12-hour shift. including the outliers, statistically there was a decrease in cfu after the completion of the shift by 96.4% (p=0.143) from 23,364 cfu to 838 cfu pre-night disinfection. this decrease is unlikely to be a true representative of bacterial load present on mobile phones without any interval cleaning considering the continued exposures throughout a hcp's shift. thus, the data excluding outliers may be more accurate. given that in the outliers, the same species of bacteria were observed in both the pre-and post-disinfection time points, we did not feel that they could be considered contaminant and fully excluded from our analysis; therefore, we present both sets of data. we found that 30% of phones had 3 or more different types of bacteria present. the most common species were bacillus spp and coryneform bacillus. the most common pathogenic species were coagulase-negative staphylococcus, acinetobacter, and s. aureus (table 1) . enterococcus faecalis 2 (7) 2 (7) pseudomonas spp. acinetobacter spp. 4 (14) 2 (7) coagulase-negative staphylococcus spp. 12 (41) 18 (62) bacillus cereus 0 (0) 2 (7) table 1 . pathogenic bacteria found on medical staff mobile phones prior to 30 second uv-c disinfection cycles before and after shift. all 29 providers filled out a pre-study survey (supplemental table 1 ) and a post-study survey ( figure 2 ). we found 30.1% of respondents cleaned their mobile phones daily, and 37.8% cleaned their phones once a week or even less frequently. most hcps (96.4%) were concerned that their mobile device was a significant risk factor in the transmission of bacterial pathogens. we discovered that 75.4% of surveyed hcps use their mobile phones inside patients' rooms, and 44.8% of hcps use their device in a patient's room even when the patient is under contact/droplet isolation precautions. furthermore, 89.7% of hcps expressed that physicians and nurses should take active measures to disinfect their phone during their shift. of the respondents, 69% reported prior knowledge of using uv light as a disinfection technique. after using the device, our post-survey showed that 100% of surveyed hcps endorsed that the uv-c device was easy to use, that they were interested in using the device, and that the hospital would benefit from mobile phone disinfection. ultraviolet light presents a renewable, effective, and easy-to-use disinfection method that has the potential to conserve hospital resources and decrease the healthcare-associated transmission of bacteria and viruses. our hcps' mobile phones were found to have a significant bacterial burden with over 250,000 cfu of pathogenic bacteria on average. our protocol utilizing uv-c disinfection demonstrated high effectiveness with a significant decrease in both total and pathogenic polymicrobial bacterial load. pathogenic bacteria were found on the majority of phones in high concentrations, which could potentially impact hai rates such as central line associated bloodstream infections, ventilator associated pneumonias, and wound infections. all of our surveyed hcps found the device easy and convenient to use and endorsed the need to implement ultraviolet light disinfection for mobile phones in hospitals. our study showed the presence of a significant bacterial load on phones with important pathogens. this is consistent with previous studies, which have found that 60-96% of phones demonstrated evidence of bacterial contamination with 21-38% growing three or more different species. 1, 2 mobile phones present a potential risk for the transmission of hais in the operating room and the intensive care unit (icu) with the phones demonstrating a high frequency of mrsa and gram negative bacteria. 3, 4 despite the risks posed by mobile phones, it is impractical to limit or ban their use in hospitals. the majority of providers would not support such measures, and previous attempts in united kingdom hospitals have failed due to the widespread use of mobile phones by providers for key communication. 2, 6 currently, mobile phone wipes are available for cleaning, but they are not proven to be true disinfectants and are a nonrenewable resource and subject to shortages. therefore, an effective and easy-to-use disinfection method for mobile phones such as uv-c light provides value and potentially helps reduce hais. in our study, uv-c light was effective in nearly eliminating the total and pathogenic bacterial load found on phones. uv light's role in the medical field is rapidly expanding with its main use residing in the nursing home setting and in or sterilization. 16 uv light has high efficacy on a wide range of pathogenic bacteria with successful elimination of pathogens such as mrsa, vre and c. diff. 10-12 uv light has been shown to be as effective or potentially more effective compared to accelerated hydrogen peroxide for surfaces and neutral detergent for floors in decontamination after patient use. [17] [18] [19] furthermore, in light of the need for renewable methods for disinfection with the novel coronavirus disease (covid-19) pandemic, uv-c light has been shown to be effective in disinfecting viral aerosols, specifically coronavirus. 20 another study found that uv-c light reduces infectivity of severe acute respiratory syndrome-coronavirus-1 (sars-cov-1) in plasma. 21 the use of a uv-c device can present an easy-to-use and effective disinfection method which has the potential to prevent the spread of sars-cov-2 via fomites such as mobile phones within a medical/surgical hospital unit. the potential benefits of implementing mobile phone uv-c disinfecting devices which do not consume valuable resources such as germicidal wipes in a pandemic may be far reaching. this may also further mitigate transmission if usage is standardized as providers are leaving the hospital to their families. our hcps reported high rates of using phones during rounds and in patient rooms including combined/droplet isolation rooms which could contribute to the rates of pathogenic bacteria found. the majority of them felt that doctors and nurses should clean their phones upon entering and leaving the hospital. despite this belief, hcps identified a clear lack of standard mobile phone disinfection practices with many individuals failing to disinfect their mobile devices weekly. respondents identified the uv-c device's ease of use and their willingness to use it daily to weekly. this is more frequent than current phone disinfection practices at our institution. consistent with prior studies, our respondents agree that mobile phones are a high risk for potential infection transmission. 2, 5 this was further supported by their responses anticipating multiple different bacterial colonies and even possible resistant bacteria on their phones. we believe that implementing the use of this device in conjunction with ongoing hand hygiene efforts could change practices. this subsequently could have lasting effects on reducing hais and potentially protect hcps and their families. limitations to this study include a small sample size; however, our sample size was large enough to power our study to demonstrate significant changes in bacterial loads. another limitation includes a lack of a direct comparison to a more standard method of mobile device disinfecting-germicidal wipes, which were infrequently used to clean personal mobile phone devices in our institution. this study was also done at a single academic pediatric hospital. different mobile phone bacterial colonization patterns may be seen at adult hospitals or in different healthcare settings. finally, this study did not further characterize the bacteria as mrsa or resistant gram-negative organisms, which would shed further light on the potential clinical significance of our results. studies are underway to show that the decrease in bacterial burden translates to clinically significant reductions in infection rates. future areas for investigation include assessing the effectiveness of uv-c disinfection devices on sars-cov-2 and other potential pandemic pathogens and the utility of widespread implementation of uv-c disinfection devices in a hospital system. we anticipate this is an opportunity to renew discussion of fomite decontaminating techniques and environmental hygiene beyond mobile phones in the clinical setting as uv-c and other novel disinfection methods arise. conclusions: this novel uv-c cleaning device is effective in reducing both total and pathogenic bacteria on mobile phones by over 90-99%. hcps would frequently use a phone disinfecting device to reduce infection risk and found it convenient and beneficial. in light of the covid-19 pandemic, a standardized approach to phone disinfection would be valuable in preventing hais and protecting hcps themselves. is your phone bugged? the incidence of bacteria known to cause nosocomial infection on healthcare workers' mobile phones mobile phones in clinical practice: reducing the risk of bacterial contamination are we aware how contaminated our mobile phones with nosocomial pathogens? are healthcare workers' mobile phones a potential source of nosocomial infections? review of the literature healthcare workers mobile phone usage: a potential risk for viral contamination. surveillance pilot study mobile phone technology and hospitalized patients: a cross-sectional surveillance study of bacterial colonization, and patient opinions and behaviours evaluation of a pulsed xenon ultraviolet disinfection system to decrease bacterial contamination in operating rooms environmental effectiveness of pulsed-xenon light in the operating room evaluation of a hand-held farultraviolet radiation device for decontamination of clostridium difficile and other healthcareassociated pathogens effect of uv-c light or hydrogen peroxide wipes on the inactivation of methicillin-resistant staphylococcus aureus, clostridium difficile spores and norovirus surrogate no-touch disinfection methods to decrease organism infections: a systematic review and meta-analysis evaluating the effectiveness of ultraviolet-c lamps for reducing keyboard contamination in the intensive care unit: a longitudinal analysis phonesoap med cleans smartphones, tablets, stethoscopes with uv evaluation of an ultraviolet room disinfection protocol to decrease nursing home microbial burden, infection and hospitalization rates rapid hospital room decontamination using ultraviolet (uv) light with a nanostructured uv-reflective wall coating room decontamination using an ultraviolet-c device with short ultraviolet exposure time postdischarge decontamination of mrsa, vre, and clostridium difficile isolation rooms using 2 commercially available automated ultraviolet-c-emitting devices effect of ultraviolet germicidal irradiation on viral aerosols inactivation of three emerging viruses -severe acute respiratory syndrome coronavirus, crimean-congo haemorrhagic fever virus and nipah virus -in platelet concentrates by ultraviolet c light and in plasma by methylene blue plus visible light financial support. financial support provided by phonesoap (provo, ut) was limited to the cost of environmental culturing at a third-party reference laboratory.potential conflicts of interest. all authors report no conflicts of interest relevant to this article. key: cord-290441-r4tzodkj authors: iversen, anne-mette; stangerup, marie; from-hansen, michelle; hansen, rosa; sode, louise palasin; kostadinov, krassimir; hansen, marco bo; calum, henrik; ellermann-eriksen, svend; knudsen, jenny dahl title: light-guided nudging and data-driven performance feedback improve hand hygiene compliance among nurses and doctors date: 2020-11-10 journal: am j infect control doi: 10.1016/j.ajic.2020.11.007 sha: doc_id: 290441 cord_uid: r4tzodkj background: evidence-based practices to increase hand hygiene compliance (hhc) among healthcare workers are warranted. we aimed to investigate the effect of a multimodal strategy on hhc. methods: during this 14-months prospective, observational study, an automated monitoring system was implemented in a 29-beds surgical ward. hand hygiene opportunities and alcohol-based hand rubbing events were measured in patient and working rooms (medication, utility, storerooms, toilets). we compared baseline hhc of healthcare workers across periods with light-guided nudging from sensors on dispensers and data-driven performance feedback (multimodal strategy) using the student's t-test. results: the doctors (n=10) significantly increased their hhc in patient rooms (16% vs. 42%, p<0.0001) and working rooms (24% vs. 78%, p=0.0006) when using the multimodal strategy. the nurses (n=26) also increased their hhc significantly from baseline in both patient rooms (27% vs. 43%, p=0.0005) and working rooms (39% vs. 64%, p<0.0001). the nurses (n=9), who subsequently received individual performance feedback, further increased hhc, compared with the period when they received group performance feedback (patient rooms: 43% vs. 55%, p<0.0001 and working rooms: 64% vs. 80%, p<0.0001). conclusions: hhc of doctors and nurses can be significantly improved with light-guided nudging and data-driven performance feedback using an automated hand hygiene system.  doctors (surgeons) have lower baseline hand hygiene compliance than nurses  light-guided nudging and data-driven performance feedback improve compliance  individual performance feedback might be more effective than group feedback  the sani nudge system detects more opportunities than using manual observations  nurses and doctors disinfect hands more often after rather than before patient contact background evidence-based practices to increase hand hygiene compliance (hhc) among healthcare workers are warranted. we aimed to investigate the effect of a multimodal strategy on hhc. during this 14-months prospective, observational study, an automated monitoring system was implemented in a 29-beds surgical ward. hand hygiene opportunities and alcohol-based hand rubbing events were measured in patient and working rooms (medication, utility, storerooms, toilets). we compared baseline hhc of healthcare workers across periods with light-guided nudging from sensors on dispensers and data-driven performance feedback (multimodal strategy) using the student's t-test. the doctors (n=10) significantly increased their hhc in patient rooms (16% vs. 42%, p<0.0001) and working rooms (24% vs. 78%, p=0.0006) when using the multimodal strategy. the nurses (n=26) also increased their hhc significantly from baseline in both patient rooms (27% vs. 43%, p=0.0005) and working rooms (39% vs. 64%, p<0.0001). the nurses (n=9), who subsequently received individual performance feedback, further increased hhc, compared with the period when they received group performance feedback (patient rooms: 43% vs. 55%, p<0.0001 and working rooms: 64% vs. 80%, p<0.0001). hhc of doctors and nurses can be significantly improved with light-guided nudging and data-driven performance feedback using an automated hand hygiene system. light-guided nudging and data-driven performance feedback improve hand hygiene compliance among nurses and doctors background hospital-acquired infections (hais) continue to burden patients, healthcare workers (hcws) and society by increasing morbidity, mortality, absenteeism and treatment costs (1-3). the covid-19 pandemic has underlined the importance of effective infection prevention measures in hospitals, including proper hand hygiene. hcws are at the front-line, and their constant exposure to infected patients and contaminated surfaces puts them at risk of acquiring and transmitting pathogens (4) . their adherence to hand hygiene guidelines is vital in combatting infectious diseases in hospitals, especially hais and now also sars-cov-2 (5). adequate hand hygiene among hcws can prevent an estimated 15-30% of the hais (6-8) but compliance remains suboptimal (9) . many strategies have tried to improve the hand hygiene compliance (hhc) of hcws but most effects are small to moderate and often short term (6, 10, 11) . a recent cochrane review identified 26 studies which assessed the combinations of the following strategies: availability, education, reminders (verbal and written), performance feedback, administrating support and staff involvement. the authors conclude that the strategies may improve the hhc, but the certainty of evidence varies from low to moderate and the most effectful method remains unclear (12) . two systematic reviews found that multimodal strategies were more successful in improving hhc rates of hcws than single interventions (13, 14) . moreover, the improvement strategies directed towards education, motivation and continuous feedback proved to be effective. the authors also conclude that we should be more creative in the application of alternative improvement activities. now automated hand hygiene monitoring systems create an opportunity to provide real-time data and feedback using light-guided nudging (sani nudge; copenhagen, denmark, https://saninudge.com. accessed sep 20, 2020) . the author group has previously described their experiences with the automated hand hygiene monitoring system from a development and implementation perspective (15) . nudging is a friendly reminder to encourage desired behavior. it can be anything from posters to sounds or dynamic lights that change over time to mitigate "banner blindness". however, the impact of nudges on clinicians' behavior has only recently started to be formally evaluated and it is mostly investigated using static interventions, such as posters, signs, stickers, brochures, letters and emails (16, 17) . given the potential of 'nudge' strategies to impact on clinicians' behaviors, efforts to describe the application and potential effect of such strategies on hhc are warranted. we aimed to determine if a multimodal strategy, consisting of light-guided nudging and data-driven performance feedback on group and individual levels, can be used in a clinical context as a supporting tool to improve hhc among hcws. we conducted a single-site, prospective, observational, quality improvement study between february 2018 and april 2019 in a surgical department with 29 beds (3 single, 1 twin and 8 multi bedrooms) as a substudy of a multiregional project (15) . some data from the present cohort have been published elsewhere (15) . however, the hand hygiene improvement data have not previously been reported. this ward was chosen because it had a history of infectious disease outbreaks and, although normally contained within few weeks, we had the assumption that hand hygiene could be improved. in denmark, who's "my 5 moments for hand hygiene" is the standard practice (18, 19) . we focused on alcohol-based hand rubbing based on the danish national hygiene guidelines for hcws stating that hand washing must always be followed by alcohol-based hand rubbing (19) . we included both doctors and nurses from the surgical ward of which 17 of the nurses were also included in our previous study (15) . participation in the study was voluntary and data were anonymized to both study participants and investigators, except from a group of 9 nurses who volunteered to receive their own hand hygiene results via a weekly email to test how individualized performance data affect the performance. no information about the study subjects besides healthcare profession was obtained to ensure anonymity. all participants were briefed about the study purposes and placement of the hand hygiene system prior to study initiation. data were collected using an automated hand hygiene monitoring system (sani nudge, copenhagen, denmark, https://saninudge.com. accessed sep 20, 2020). sensors were placed on the existing alcohol-based hand rub dispenser solutions from where every hand hygiene event was registered, as previously described (15) . in brief, the sensors had a built-in nudging feature with discrete light symbols which was activated during selected periods of the study ( fig. 1.a) . other sensors were placed above the patient beds, creating a patient zone around each bed ( fig. 1.b) . this allows the system to be used for monitoring who moments 1 (before touching a patient), 4 (after touching a patient), and 5 (after touching patient near surroundings). moments 2 (before clean/aseptic procedures) and 3 (after body fluid exposure/risk) were included in the data because many of these procedures also take place in the patient zone. however, it was not possible to distinguish them from the other moments. finally, anonymous bluetooth sensors were placed on the existing name badge of the hcws and was coded to be either a doctor or a nurse ( fig. 1.c) . the sensors made it possible to measure when an hcw had a hand hygiene opportunity and whether alcohol-based hand rubbing was performed in that moment. a hand hygiene data report was sent on a weekly basis to the infection control nurses and the head nurse who would then show it to the hcws in the ward during bi-weekly meetings ( fig. 1.d) . after the meeting a copy of the data were put on a bulletin board for display. the system did not measure physical contact but used clinically validated algorithms based on time and distance measurements in the patient zone to calculate whether contact was most likely to have taken place. the study was divided into three phases ( table 1 ): in phase one (baseline), the system was implemented, and a compliance baseline was measured. the baseline functioned as a control period with data representing the current hhc status of the ward before the improvement initiatives began. all study participants were blinded to data during this period to minimize the risk of bias. period (months) description control period: a period without any interventions, reflecting the current hand hygiene compliance of the ward. data-driven performance feedback: the head nurse and hygiene coordinator presented the department's hand hygiene compliance for each room type (patient room, mediation room, staff toilet, dirty and clean utility rooms) followed by an open discussion on how to overcome hand hygiene barriers. a copy of the results would be put on a bulletin board for display. light-guided nudging: the sani nudge sensors, located on existing alcohol-based hand rub dispensers, used visual nudges (lights and symbols) to bring staff's attention towards hand hygiene. the visual nudges appeared when staff was in a situation that required hand sanitization. once a sanitization was performed, a smiley appeared to complete the positive feedback loop. the nudging was switched on and off with different intervals and in a random manner to avoid banner blindness. data-driven performance feedback: 8 months into phase 2, nine nurses started receiving individual performance feedback which consisted of weekly reports send by email directly to each of them. the nurses were able to see their own compliance data in each room as well as before and after patient contact. they were also able to compare their own results with the rest of their colleagues' group compliance. during phase two (group intervention: data-driven performance feedback and light-guided nudging), the head nurse and the hygiene coordinator in the ward presented the hhc to their colleagues in the ward at short (5-10 minutes) bi-weekly meetings. all hcws at work participated in the meetings. the data were shown as a general compliance number of the ward and stratified according to the following six room types: patient room, medication room, dirty utility room (sluice room for soiled goods), clean utility room (sluice room for storage of clean goods), storeroom and staff toilet. the agenda of the meetings were: the head nurse and hygiene coordinator provided an overview on the previous week's hhc to make sure that everyone was updated on the most recent data. they also followed up on the previous week's goal as an evaluation of the performance. contact'-moments. the guidelines state that we must perform hand hygiene before touching a patient (moment 1). as a goal the following week, we must all remember to sanitize hands every time we are walking into a patient room, before touching a patient". in addition, the nudging feature of the system was switched on periodically during phase 2. the nudges consisted of lights in 10 different colors (yellow, orange, red, pink, magenta, purple, blue, turquoise, dark green, lime) which were displayed by the sensors on the dispensers (fig. 1.a) . a nudge was provided when staff approached a dispenser and once alcohol-based hand rubbing was performed. in order to avoid banner blindness (i.e. unconsciously desensitization of a stimuli over time due to repeated exposure), the nudging mode (light) and length of time were switched on and off at random. the nudging colors were also displayed in a random manner. the symbols switched between random lights (cue) to increase awareness and green smileys after sanitizations (reward) to reinforce the desired behavior and create a persistent routine. during phase 3 (individual intervention: performance data on an individual level), 9 nurses volunteered to receive weekly individual compliance data by email in order to personalize the feedback. this was done automatically by the system and was blinded to the head nurse, hygiene coordinator or the rest of the staff. those not receiving individualized data continued as described in phase 2 for the rest of the study period. our primary analysis focused on the effect of light-guided nudging and data-driven performance feedback as a combined intervention (multimodal strategy). we compared the mean hhc between the baseline period and the intervention period. the secondary analysis evaluated the effect of individual performance feedback. hand hygiene performance rates were calculated by dividing hand hygiene events (number of hand we enrolled 26 nurses and 10 doctors. the system registered an average of 5000 hand hygiene opportunities in the ward per week for these 36 hcws during the study period. in general, the hhc was lowest in the patient rooms compared with the other rooms for both the doctors and the nurses ( fig. 2 and 3) . the doctors had a baseline hhc of 16% in the patient rooms and 24% in the other rooms in the ward. hhc increased significantly to 42% (p < 0.0001) in the patient rooms and to 78% (p = 0.0006) in all other situations once the nudging feature was activated and the group performance feedback used (fig. 3) . the doctors were more likely to sanitize hands after rather than before patient contact during the baseline period (21% vs. 11%, respectively). the same behavioral pattern was observed during the period with nudging and performance feedback (53% vs. 21%). the nurses had a baseline hhc of 27% in the patient rooms and 39% in the rest of the rooms in the ward. hhc increased significantly to 43% (p = 0.0002) in the patient rooms and to 64% (p < 0.0001) in all other situations once the nudging feature was activated and the group performance feedback provided (fig. 4) . the hhc of the nurses receiving individual performance feedback further increased to 55% (p < 0.0001) in the patient rooms and to 80% (p < 0.0001) in all other situations compared with the period when group level data and nudging were provided (fig. 4) . as with the doctors, the nurses were more likely to sanitize hands after rather than before patient contact during the baseline period (35% vs. 19%, respectively). the same pattern was observed during nudging and group performance feedback (50% vs. 36%) as well as during individual performance feedback (61% vs. 49%). to our knowledge, this is the first study to examine the combinatory effect of data-driven performance feedback and light-guided nudging on hhc. the multimodal intervention significantly increased hhc of both doctors and nurses. the doctors had the lowest baseline compliance but seemed to be very responsive to the intervention and reached the same compliance levels as the nurses in the patient rooms and even higher levels in the working rooms. however, the nurses receiving individual performance feedback demonstrated the best performance in all the different room types. a reason for the improvements observed could be the reduction in cognitive biases. when hais manifest several days after exposure, hcws do not encounter the consequences of poor hand hygiene and they could consider their risk of causing infections negligible (16) . when being reminded about the importance of good hand hygiene through performance feedback and via nudges in the moment, some of these cognitive barriers are removed (20) . the baseline hhc was low but comparable to other studies using automated hand hygiene monitoring systems while the improvements seen in this study are some of the highest reported (21) . the hhc was lowest in the patient rooms both before and after the intervention period. one possible factor could be that the highest number of opportunities were measured in these rooms, making higher performance more difficult. this is an important factor because most other monitoring systems only measure compliance upon room entry and exit despite that several hand hygiene opportunities occur near the patient during a single visit (21) . the sani nudge system measures compliance around the patient bed, providing a more detailed picture of the hand hygiene behavior when performing patient-centered clinical tasks. this is of particular relevance in multiple bedrooms where hcws risk moving from patient to patient without performing hand hygiene. the hhc is comparable to studies using video-monitored direct observation systems which is often considered the highest technical standard but has limited implementation possibilities due to privacy (22, 23) . the findings of this study suggest that the sani nudge system can be used when you want to measure hhc in hospital settings according to who's "my 5 moments" or hospitals who needs a more nuanced picture of the hand hygiene situation in the patient rooms than room entry and exit measurements can provide. some limitations should be considered when interpreting the results. first, a small number of hcws (n=36) were included and their behavior might not be representative for other hcws. however, the system collected a high number of opportunities compared with studies performing direct observations which provides robustness to the analyses and increases the validity. in addition, data collection was done 24/7 for 14-months whereas direct observation studies normally do it sporadically during daytime and on weekdays only, presenting a limited picture of the true hygiene performance. second, there might have been some degree of selection bias towards the nurses choosing to receive individual data. as this was based on volunteering, it is possible that those whom felt confident about their own performance were more likely to volunteer. it was not possible to investigate if they were also the top performers during the baseline period because their data was anonymized up until they consented to have individual data collected. despite this consideration, the nurses significantly improved once they started receiving individualized data compared to when they received data on group level. an explanation could be that the increased insights into their own performance reduced the dunning-kruger effect even further (24) . third, the hand hygiene system did not measure the quality of the alcohol-based hand rubbing which also has a significant impact on the effectiveness to prevent the spread of pathogens. instead we learned that the hand hygiene system should be used as a prioritization tool for the hygiene organization to identify wards, professions and hygiene moments (e.g. before and after patient contact) where hand hygiene performance is good and where there is room for improvement. it allows the management or infection prevention team to direct their limited resources to where it is mostly needed and have the highest impact in terms of infection prevention risk. creating a transparent hand hygiene performance system also enhances an ongoing knowledge sharing of best practices which is highly needed in infection prevention during routine and outbreak situations (25) . finally, we did not note down the hcws who attended the bi-weekly data presentation meetings and we can therefore not assure that all hcws got exposed to the data performance intervention. we did put a copy of the performance results on a bulletin board for display after each meeting to mitigate the risk of not being exposed to the information. future studies should consider sending out emails or using other relevant approaches to ensure that all team members get exposed to the performance feedback interventions. we found that hhc with sanitizer of both doctors and nurses can be significantly improved with light-guided nudging and data-driven performance feedback on group and individual level using an automated hand hygiene system. this study provides justification for continued investigation on how improvement strategies can be designed to achieve an optimal hhc with limited efforts and resources. this study was partly funded by the danish ministry of health (j. no. 1608966). effectiveness of a hospital-wide programme to improve compliance with hand hygiene infection control -a problem for patient safety research priority setting working group of the who world alliance for patient safety. global priorities for patient safety research respiratory viruses in the patient environment coronavirus disease (covid-19) outbreak: rights, roles and responsibilities of healthcare workers, including key considerations for occupational safety from best evidence to best practice: effective implementation of change in patients' care the preventable proportion of nosocomial infections: an overview of published reports reduction of healthcare-associated infections by exceeding high compliance with hand hygiene practices systematic review of studies on compliance with hand hygiene guidelines in hospital care improving compliance with hand hygiene in hospitals enhanced performance feedback and patient participation to improve hand hygiene compliance of health-care workers in the setting of established multimodal promotion: a single-centre, cluster randomised controlled trial interventions to improve hand hygiene compliance in patient care the effectiveness of interventions aimed at increasing handwashing in healthcare workers -a systematic review a systematic review of hand hygiene improvement strategies: a behavioural approach blinded during the review process to avoid bias nudging to improve hand hygiene nudge strategies to improve healthcare providers' implementation of evidence-based guidelines, policies and practices: a systematic review of trials included within cochrane systematic reviews world health organization. my 5 moments for hand hygiene the danish national hand hygiene guidelines (nationale infektionshygiejniske retningslinjer monitoring hand hygiene: meaningless, harmful, or helpful? automated and electronically assisted hand hygiene monitoring systems: a systematic review infection-free surgery: how to improve hand-hygiene compliance and eradicate methicillin-resistant staphylococcus aureus from surgical wards using hightechnology to enforce low-technology safety measures: the use of third-party remote video auditing and real-time feedback in healthcare unskilled and unaware of it: how difficulties in recognizing one's own incompetence lead to inflated self-assessments knowledge sharing in infection prevention in routine and outbreak situations: a survey of the society for healthcare epidemiology of america research network we thank all the hcws who took part in the study. key: cord-304124-ym9mf5wz authors: li, jia; he, xue; yuanyuan; zhang, wei; li, xue; zhang, yuhua; li, shaoxiang; guan, chunyan; gao, zifen; dong, gehong title: meta-analysis investigating the relationship between clinical features, outcomes, and severity of severe acute respiratory syndrome coronavirus 2 (sars-cov-2) pneumonia date: 2020-06-12 journal: am j infect control doi: 10.1016/j.ajic.2020.06.008 sha: doc_id: 304124 cord_uid: ym9mf5wz objective: we aimed to investigate the relationship between clinical characteristics, outcomes and the severity of severe acute respiratory syndrome coronavirus 2 (sars-cov-2) pneumonia. methods: we performed a systematic review and meta-analysis using pubmed, embase, and cochrane library databases to assess the clinical characteristics and outcomes of confirmed covid-19 cases and compared severe (icu) and non-severe (non-icu) groups. results: we included 12 cohort studies including 2445 patients with covid-19. compared with non-severe (non-icu) patients, severe (icu) disease was associated with a smoking history (p=0.003) and comorbidities including chronic obstructive pulmonary disease (or=5.08, p<0.001), diabetes (or=3.17, p<0.001), hypertension (or=2.40, p<0.001), coronary heart disease (or=2.66, p<0.001), cerebrovascular diseases (or=2.68, p=0.008), and malignancy (or=2.21, p=0.040). we found significant differences between the two groups for fever, dyspnea, decreased lymphocyte and platelet counts, and increased leukocyte count, c-creative protein, procalcitonin, lactose dehydrogenase, aspartate aminotransferase, alanine aminotransferase, creatinine kinase, and creatinine levels (p<0.05). significant differences were also observed for multiple treatments (p<0.05). patients in the severe (icu) group were more likely to have complications and had a much higher mortality rate and lower discharge rate than those with non-severe (non-icu) disease (p<0.05). conclusions: investigation of clinical characteristics and outcomes of severe cases of covid-19 will contribute to early prediction, accurate diagnosis, and treatment to improve the prognosis of patients with severe illness. a series of pneumonia cases of unknown cause appeared in wuhan, china in december, 2019. scientists isolated the pathogen that caused the pneumonia, which was named 2019-ncov, a novel type of beta-coronavirus . the world health organization later renamed the new virus severe acute respiratory syndrome coronavirus 2 (sars-cov-2) and named the illness caused by the virus coronavirus disease 2019 . as of april 27, the total number of patients with covid-19 had risen sharply to 2, 878,196 patients globally, with 198 ,668 deaths and a mortality rate close to 6.9% (data from the website of the who). people infected by sars-cov-2 have a very broad spectrum of illness, from being asymptomatic to critically ill (bai et al. 2020) . thus, it is crucial to detect patients who are more likely to develop severe illness at diagnosis, to decrease mortality in these patients. in this study, we aimed to determine the predictors of severe disease or admission to an intensive care unit (icu) in a meta-analysis by comparing patients with covid-19 in severe (icu) and non-severe (non-icu) groups. we searched the pubmed, embase, and cochrane library databases for studies on covid-19 published between december 2019 and april 14, 2020 . the search terms and key words used included "novel coronavirus" or "2019-ncov" or "2019 novel coronavirus" or "ncip" or "novel coronavirus infected pneumonia" or "covid-19" or "severe acute respiratory syndrome coronavirus 2" or "sars-cov2" and "clinical". we also searched the medrxiv website, a free online archive and distribution service of unpublished preprints in the medical field (https://www.medrxiv.org), to identify the latest studies on the novel coronavirus. there was no language restriction. this meta-analysis followed the recommendations established by the preferred reporting items for systematic reviews and meta-analyses (prisma) statement (moher et al. 2010) . studies included in this meta-analysis were selected based on the following inclusion and exclusion criteria. the inclusion criteria were: (1) cohort studies or case-control studies reporting the clinical characteristics of patients with sars-cov2infection; (2) one or more clinical features were analyzed, including epidemiology, clinical symptoms, laboratory findings, comorbidities, treatment, complications, and outcomes; (3) patients were grouped according to the severity of disease, e.g., severe and non-severe groups or icu and non-icu groups. the exclusion criteria were: (1) review articles, opinions, and letters, which did not present original data; (2) studies without grouping according to the severity of illness; and (3) studies grouping patients by age or survival status. all articles were managed using endnote x 9.1 software. we first screened article titles and abstracts to exclude those that clearly did not meet the inclusion criteria. we then read the full text to select the articles to finally include in this meta-analysis. two researchers (j. l and x. h) extracted the data from eligible studies independently, to minimize bias. if any disagreements arose, discussions were held with a third investigator (g. d) to reach consensus. we extracted and analyzed items from eligible studies including the country, year, date of publication, the number of reported cases, sex, age, clinical symptoms and signs, comorbidities, laboratory findings, complications, and outcomes of patients with sars-cov2 infection who had severe (icu) and non-severe (non-icu) disease. to evaluate quality, we used the newcastle-ottawa scale to assess cohort studies and case-control studies (stang 2010) . the highest quality rating was 9 stars and the lowest was 0 stars. assessment scores ≥7 indicated high-quality studies. we used the number of events per group to calculate odds ratios (ors) and their 95% confidence intervals (cis) with stata version 14.0 (statacorp llc, college station, tx, usa). the pooled results were presented as forest plots. the pooled prevalence and 95% ci in severe (icu) cases was calculated using a single-arm meta-analysis. measures of heterogeneity, including the cochran's q, i 2 , and chi-squared tests were estimated and reported (higgins et al. 2003) . ors were combined using the mantel-haenszel fixed-effects model to estimate and compare risk factors and their confidence intervals. when substantial heterogeneity was detected (i 2 >50%), the dersimonian-laird random-effects model was used (dersimonian and laird 1986). to further explore sources of heterogeneity and to examine whether the results differed by study characteristics, subgroup analyses were performed by geographic region (wuhan area and outside wuhan area) and by study size (≤50 cases and >50 cases). p<0.05 was considered to indicate a statistically significant test result for the pooled ors. a total of 250 papers were retrieved using the search strategy, and 49 articles were excluded because of duplication. after screening the article titles and abstracts, 35 papers were selected for full-text assessment. of these articles, 18 were excluded because of a lack of information on severe cases and five were excluded because study participants were grouped by age or survival status. study selection and flow are shown in figure 1 . finally, we included a total of twelve studies, conducted between january 1 st and april 14, 2020 and representing 2445 patients with confirmed sars-cov-2 infection; among these, 479 had severe illness or were admitted to the icu (cao et al. 2020 , chu et al. 2020 , feng et al. 2020 , gao et al. 2020 , guan et al. 2020 , wan et al. 2020 . all studies were conducted in china and all articles were written in english. the characteristics of the included articles are shown in table 1 . the pooled prevalence of severe or icu cases was 0.33 (95% ci: 0.22-0.43) ( figure 2 ). the data on demographic characteristics (sex, smoking history, wuhan exposure history) and comorbidities (hypertension, diabetes, and so on) among patients with severe (icu) and non-severe (non-icu) covid-19 were extracted and pooled for meta-analysis. the results showed that there was no significant association between sex (or=1.14, 95% ci: 0.91-1.43, i 2 =0.0%, p=0.267) or wuhan exposure history (or=0.92, 95% ci: 0.53-1.59, i 2 =0.0%, p=0.764) and increased risk of severe disease ( figure 3a , 3b). however, our results showed that a smoking history was significantly associated with severe covid-19 (or=1.70, 95% ci: 1.20-2.41, i 2 =43.4%, p=0.003) ( figure 3c ). compared with non-severe patients, those with severe illness or admission to the icu were more likely to have one or more comorbidities (or=3.07, 95% ci: 1.56-6.05, p<0.001, i 2 =79.0%), including chronic obstructive pulmonary disease (or=5.08, 95% ci: 2.68-9.63, p<0.001, figure 1a -1g) . no significant differences were observed between the two groups for chronic liver disease (p=0.192) and chronic renal disease (p=0.404) (supplementary figure 1h, 1i) . among all clinical symptoms, fever and dyspnea were found to be significantly associated with more severe covid-19. the combined ors ci: 1.69-3.55, p<0.001, i 2 =46.7%), and creatinine (or=2.14, 95% ci: 1.14-4.01, p=0.018, i 2 =0.0%) were observed to be significantly associated with severe (icu) cases as compared with non-severe (figure 5a-5c ). no significant difference was detected for the complication of acute cardiac injury in the two groups (p=0.194) ( figure 5d ). by the end of the follow-up period, the outcomes of patients with covid-19 included hospitalization, discharge, and death. a small number of patients were lost to follow-up. there was a significant difference between the severe (icu) group and non-severe (non-icu) group in the number of discharges (or=0.51, 95% ci: 0.29-0.88, p=0.017, i 2 =36.3%) and deaths (or=13.03, 95% ci: 2.54-66.87, p=0.002, i 2 =57.7%) ( figure 6a, 6b) . patients with more severe illness have a much higher mortality rate and lower discharge rate than those with mild or moderate illness.there was no significant difference in the number of hospitalized patients (p=0.848) ( figure 6c ). we conducted subgroup analyses of geographic region and study size to explore potential sources of heterogeneity (i 2 >50%). no clear sources of heterogeneity were identified from these subgroup analyses (table 2) . to date, this is the first systematic review and meta-analysis to investigate the relationship between clinical characteristics, outcomes, and severity of sars-cov-2pneumonia. we collected data from 12 published articles including 2445 patients with confirmed sars-cov-2 infection and 479 patients with severe disease or icu admission. the pooled prevalence of severe or icu cases was 33%. there was no association between sex or wuhan exposure history and severity of covid-19. however, our results showed that smoking history might be a high-risk factor for severe illness, which was consistent with the conclusion of recently reported research . among clinical symptoms, fever and dyspnea were found to be significantly associated with severe illness or icu admission for covid-19. however, in patients with fever, high fever (>39℃) was not a risk factor of severe illness. based on this study, fever that is not particularly high might be associated with severe covid-19. thus, greater attention is needed for patients with fever or dyspnea. patients with any comorbidities had a higher rate of severe illness; these included chronic obstructive pulmonary disease (copd), diabetes, hypertension, coronary heart disease, cerebrovascular diseases, and malignancy. assessment of all potential comorbidities is challenging in any study, so the most common and well-studied comorbidities assessed in the original articles were chosen for evaluation. as for laboratory findings, increased leukocyte count, decreased lymphocyte and platelet counts, increased levels of c-creative protein, procalcitonin, ldh, ast, alt, ck, and creatinine were related to severe illness or icu admission with covid-19. different from the results of previous studies , guan et al. 2020 , our study indicated that severe illness or icu admission for sars-cov-2 pneumonia had more to do with leukocytosis than leukopenia. we speculate that leukocytosis is a reflection of excessive inflammation, which is also reflected in the much higher c-reactive protein levels among patients with severe (icu) covid-19.lymphopenia was more common in severe (icu) than in non-severe (non-icu) patients, probably owing to translocation of lymphocytes from peripheral blood to the lungs . our results regarding elevated levels of alt, ast, creatinine, ck, and ldh indicated that patients with severe disease or those in the icu had more obvious liver function, kidney function, and myocardial injury. continuous tracking of laboratory findings is crucial to identify those patients who may progress to severe status. currently, there are no specific treatments for covid-19. at present, effective measures to control the disease are early diagnosis, isolation, and supportive treatment for infected patients. as we found in our study, patients with severe illness or those in the icu most commonly received antibiotics, antivirals, corticosteroid therapy and especially advanced life support treatments including ecmo, mechanical ventilation, and continuous renal replacement therapy. significant differences were also observed in the complications of ards, shock, and acute kidney injury between the groups with different degrees of disease severity. severely ill patients or those cared for in the icu had a higher mortality rate and lower discharge rate than non-severe patients or patients without icu admission. this study has several limitations that must be mentioned. first, the studies included in our research divided patients into severe and non-severe groups (10 studies) or by admission to the icu or no icu admission (2 studies). the grouping criteria were not strictly consistent; mild and moderate cases were included in non-severe groups. second, there were differences in the range of normal values for laboratory indicators between different clinical laboratories. third, all patients in the included studies were from china, and the number of cases was limited. at the time of writing, few studies have yet been published from other countries experiencing covid-19 outbreaks such as italy, spain and the usa. in fact, no articles from countries other than china met the inclusion criteria for our analysis. further investigation including a greater number of studies with a broad geographic scope and larger sample size is needed, to obtain a more comprehensive understanding of covid-19. finally, significant heterogeneity was detected in the statistical results for several items. to address this heterogeneity, we used random effects modeling and performed subgroup analyses to identify potential sources of heterogeneity. unfortunately, no clear source of heterogeneity was identifiable. clinical characteristics are related to many factors including basic physical condition, disease progression, and examination and treatment conditions. multiple factors may have contributed to high heterogeneity; these require further research and exploration. this is the first meta-analysis to investigate the differences in clinical characteristics and outcomes between patients with covid-19 who have different degrees of disease severity. our study results will be helpful in identifying high-risk factors in patients with severe illness, which will contribute to early prediction, accurate diagnosis, and treatment of patients with covid-19. jia li, xue he and gehong dong participated in study design; jia li and xue he performed data extraction and data analysis; jia li and yuan yuan drafted the manuscript; all authors provided critical review of the manuscript and approved the final draft for publication. approval was not required. a novel coronavirus from patients with pneumonia in china presumed asymptomatic carrier transmission of covid-19 preferred reporting items for systematic reviews and meta-analyses: the prisma statement critical evaluation of the newcastle-ottawa scale for the assessment of the quality of nonrandomized studies in meta-analyses measuring inconsistency in meta-analyses meta-analysis in clinical trials clinical features and laboratory inspection of novel coronavirus pneumonia (covid-19 clinical characteristics of 54 medical staff with covid-19: a retrospective study in a single center in wuhan covid-19 with different severity: a multi-center study of clinical features diagnostic utility of clinical laboratory data determinations for patients with the severe covid-19 clinical characteristics of coronavirus disease 2019 in china clinical features of patients infected with 2019 novel coronavirus in wuhan clinical and transmission characteristics of covid-19 -a retrospective study of 25 cases from a single thoracic surgery department clinical features and treatment of covid-19 patients in northeast chongqing clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus-infected pneumonia in wuhan clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by sars-cov-2 analysis of clinical characteristics and laboratory findings of 95 cases of 2019 novel coronavirus pneumonia in wuhan, china: a retrospective analysis clinical characteristics of 161 cases of corona virus disease 2019 (covid-19) in changsha genetic recombination, and pathogenesis of coronaviruses isolation of a novel coronavirus from a man with pneumonia in saudi arabia the impact of copd and smoking history on the severity of covid-19: a systemic review and meta-analysis epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in wuhan, china: a descriptive study pathological findings of covid-19 associated with acute respiratory distress syndrome we thank liwen bianji, edanz group china (www.liwenbianji.cn/ac), for editing the english text of a draft of this manuscript. key: cord-322923-zxraxgl1 authors: bayersdorfer, jennifer; giboney, sue; martin, rosemary; moore, andria; bartles, rebecca title: novel manufacturing of simple masks in response to international shortages: bacterial and particulate filtration efficiency testing date: 2020-07-16 journal: am j infect control doi: 10.1016/j.ajic.2020.07.019 sha: doc_id: 322923 cord_uid: zxraxgl1 many healthcare systems have been forced to outsource simple mask production due to international shortages caused by the covid-19 pandemic. providence created simple masks using surgical wrap and submitted samples to an environmental lab for bacterial filtration efficiency testing. bacterial filtration efficiency (bfe) rates ranged from 83.0 – 98.1% depending on specific material and ply, and particular filtration efficiency (pfe) rates ranged from 92.3-97.7%. based on mask configuration, specific surgical wrap selected, and ply, the recommended filtration efficiency for isolation and surgical masks of 95% and 98%, respectively can be achieved. these alternative masks can allow for similar coverage and safety when hospital-grade isolation masks are in short supply. many healthcare systems have been forced to outsource simple mask production due to international shortages caused by the covid-19 pandemic. providence created simple masks using surgical wrap and submitted samples to an environmental lab for bacterial filtration efficiency testing. bacterial filtration efficiency (bfe) rates ranged from 83.0 -98.1% depending on specific material and ply, and particular filtration efficiency (pfe) rates ranged from 92.3-97.7%. based on mask configuration, specific surgical wrap selected, and ply, the recommended filtration efficiency for isolation and surgical masks of 95% and 98%, respectively can be achieved. these alternative masks can allow for similar coverage and safety when hospital-grade isolation masks are in short supply. in january of 2020, the first covid-19 case in the united states was identified. the patient was cared for at providence regional medical center everett (prmce) in everett, wa, near seattle. prmce is part of providence, a much larger integrated care network, including 51 hospitals, over 1000 ambulatory care settings, and many long-term and home care programs. as covid-19 spread in the puget sound area, many providence facilities were required to quickly respond to an exceptionally rapid increase in covid-19 cases and reports of patients under investigation. at the same time, personal protective resources became scarce, following many interruptions along the complex network that makes up the healthcare supply chain. healthcare facilities rely on personal protective equipment (ppe) in order to protect their staff from disease transmission. ppe is often manufactured outside of the united states in order to reduce cost, and much of the ppe used in the u.s. is produced in asia. during the covid-19 pandemic, a perfect storm interrupted the supply chain at multiple points -reduced manufacture, shipping, and distribution, alongside significantly increased demand. when it became apparent that some facilities were at risk of running out of masks within days and that replacement stock was unavailable throughout the u.s., providence leaders partnered with local manufacturers to quickly convert their production lines to produce simple masks. healthcare quality masks are rated based on bacterial and particulate filtration efficiency as well as fluid resistance, differential pressure, and flammability. astm standards are widely accepted as the routine standards for production and testing of healthcare quality face masks. astm f2100-e1 1 groups masks into three performance levels (level 1, 2, and 3) based on bacterial filtration efficiencies (bfe) of ≥95%, ≥98%, and 98%, respectively and sub-micron particulate filtration efficiency (pfe) of ≥95%, ≥98%, and 98%, respectively. inclusion in each performance level also requires specific rankings in differential pressure, resistance to penetration by synthetic blood, and flammability which were not considered as part of this study. astm level 1 masks are considered appropriate for low barrier precautions in short procedures and exams that don't involve aerosols, sprays or fluids. astm level 2 masks are considered appropriate for moderate barrier protection for low to moderate levels of aerosols, spray and/or fluids. rates. four different surgical wraps, all from the medline gem series, were used due to availability. eight mask prototypes were constructed in a consistent tri-fold design from each type of gem wrap and single or double material layers (see figure 1 ). all eight prototypes were sent to an environmental lab for bacterial filtration efficiency testing, latex particle filtration efficiency testing, and delta p testing. due to communication issues at the environmental laboratory, bfe/delta p was tested on only four prototypes and pfe was tested on the other four. bfe results ranged from 96.3% to 98.1% in two ply masks produced with medline gem 1, 2, and 3 materials (see table 1 ). bfe results ranged from 83.0% to 97.7% in one ply masks produced with medline gem 1, 2, and 3 (materials are distributed as single ply and were separated prior to mask manufacture). pfe results were similar to bfe results and ranged from 92.3% to 97.7% for one and two ply masks produced with medline gem 2 and gem 3. of note gem 3 one ply mask (prototype h) had a pfe rating of 97.7% which is the only 1 ply mask that demonstrating filtration efficiency >95%. the massive global shortages of ppe supply that arose in early 2020 during the covid-19 pandemic clarified the need for larger strategic caches and back-up methods for generating ppe during a future event. the rapid creation and manufacture of simple surgical masks with similar bacterial filtration efficiency as astm 1 rated masks illustrates one method for future planning in the event that mask shortages arise again. although the masks distributed to staff at providence were created using an assembly line and professional seamstresses, the same product outcome could be achieved using a simple sewing machine. although not ideal, the use of surgical wrap to quickly produce a high quality isolation mask does offer a feasible solution when mask supplies are critically low to ensure healthcare services can continue to be provided while keeping healthcare workers safe. user feedback was gathered regarding original design and comfort by direct caregiver application and trial. prototypes were hand-delivered to hospital units where nursing staff donned the masks and provided specific feedback for consideration and adoption, directly to the designer, who inturn influenced future patterns and manufacturing.healthcare worker reception was very positive to the novel manufactured masks. feedback was received regarding design and breathability, and users felt that both aspects were equal to or better than traditional masks. ppe supply is critical to the health and safety of healthcare workers. investments in growing adequate and appropriate caches of materials are critical, as are investments in identifying methods for quickly generating ppe locally during times of low supply. the method described in this paper could be easily replicated at other sites for use when supplies are critically low and use of locally manufactured masks with known bfe ratings are logically superior to alternatives (like cloth masks or scarves). limitations of this study include assessment of other astm criteria, including flammability and fluid permeability. although some data is likely available regarding these characteristics of surgical wrap, that information was not explored as part of this study due to the urgency of need for rapid production. utilizing a full face shield over the surgical wrap mask can reduce the risk of fluid exposure. masks produced outside of normal distribution processes also lack necessary regulatory approvals. these masks were not labeled as healthcare quality and were only used for limited periods of time while astm rated masks were unavailable. standard specification for performance of materials used in medical face masks. world trade organization technical barriers to trade committee testing the efficacy of homemade masks: would they protect in an influenza pandemic sincere thank you to the team from kaas upholstered for their support with rapid mask production during a time of great need.none of the authors report conflicts of interest. face mask key: cord-299475-p6cc98xa authors: to, kin-wang; lee, sing; chan, tat-on; lee, shui-shan title: exploring determinants of acceptance of the pandemic influenza a (h1n1) 2009 vaccination in nurses date: 2010-06-20 journal: am j infect control doi: 10.1016/j.ajic.2010.05.015 sha: doc_id: 299475 cord_uid: p6cc98xa this study investigated the anticipated vaccination rate against pandemic human influenza a (h1n1) 2009 in the health care setting. self-administered questionnaires were used to assess nurses' acceptance of vaccination against seasonal flu and h1n1. they were sent to nurses by post through various nurses' unions before initiation of the vaccination program. only 13.3% of the respondents planned to receive the h1n1 vaccine, compared with 37.5% for the seasonal influenza vaccine. vaccination against seasonal influenza in the preceding season strongly predicted the likelihood of h1n1 vaccination. the main reason cited for h1n1 vaccination was self-protection, and reasons for rejecting vaccination included possible side effects, ineffectiveness of the vaccine, and the mild nature of the disease. personal contact with patients with h1n1 or severe acute respiratory syndrome at work did not significantly increase the likelihood of receiving the h1n1 vaccine. more than 40% of the respondents were undecided at the time of the survey. the promotion of vaccination against seasonal influenza may play a role in improving h1n1 vaccination coverage. efforts are needed to address concerns about vaccination risk and to incorporate h1n1 vaccination in standard infection control practice with policy support. vaccination against influenza protects health care workers (hcws) and patients from contracting influenza by reducing virus transmission in health service settings. vaccination of hcws is an important strategy, because infected hcws can be a source of infection to patients. reducing hcws' risk of acquiring infection protects patients indirectly. because it is easier to target hcws for vaccination than the general public, vaccinating hcws is a sound strategy to protect patients. however, vaccination coverage in hcws has been notoriously unsatisfactory, with rates ranging from about 30% to 70% in different countries. [1] [2] [3] [4] major barriers to vaccination include misconceptions about the rationale for vaccination, perceived ineffectiveness of the vaccine, perceived unlikelihood of contracting influenza, potential side effects, fear of injection, and lack of time. [5] [6] [7] the recent emergence of pandemic human influenza a (h1n1) in 2009 is stressing the health care system because of the lack of immunity in the public and the associated mortality and morbidity. 8, 9 the possibility of genetic reassortment between different subtypes of influenza giving rise to more resistant genotype is another concern, which may potentially lead to new pandemics. [10] [11] [12] [13] vaccination is a timehonored strategy for preventing h1n1, which can predictably reduce mortality and morbidity. whereas there are abundant data on factors affecting the acceptance of seasonal influenza vaccine, those on h1n1 vaccination are scarce. in many countries, the first wave of pandemic h1n1 has come and gone. to enhance our preparedness for the impending second wave, which has yet to arrive in some countries in the northern hemisphere, we conducted a survey to estimate the acceptance rate of h1n1 vaccination in a group of nurses, and to explore factors that might be associated with vaccination uptake. nurses registered as members of the hong kong nurses general union, the nurses branch, and the enrolled nurses branch of the hong kong chinese civil servants association were invited to participate in a self-administered anonymous questionnaire survey on infection control practices relating to influenza prevention that has been conducted every 1-2 years since 2006. 14, 15 the 2009 questionnaire, constructed in chinese, together with an introductory letter explaining the purpose and nature of the study, was delivered to each individual member's postal address. the content was developed after discussions with nurses in the field, followed by pilot testing before administration. approval was obtained from the survey and behavioral research ethics committee of the chinese university of hong kong. the questionnaire was divided into 4 parts. part a assessed the respondent's vaccination status in terms of seasonal influenza in the preceding year and his or her willingness to receive vaccination against seasonal influenza and h1n1 in the coming season. the reasons for receiving or rejecting vaccination (eg, perceptions regarding protection of themselves, relatives, and patients, mandatory requirement, circumstances of the outbreak) were also assessed. the respondent was asked to select and rank 9 reasons that might have affected the decision for vaccination using a scale of 1 (most important) to 9 (least important). part b assessed the respondent's exposure to h1n1 in the workplace or family. part c assessed the respondent's agreement with government policies for preventing h1n1 and the perceived severity of h1n1 compared with h5n1 (avian) or seasonal influenza. the responses were evaluated on a likert scale ranging from 1 (most disagreed) to 6 (most agreed). part d consisted of questions on demographics and work nature in terms of clinical exposure. data entry was performed using microsoft excel (microsoft, redmond, wa). statistical analysis was performed with spss version 13.0 (spss inc, chicago, il). nonparametric tests were used to analyze ordinal data. dichotomous data were further analyzed by binary logistic regression analysis for odds ratio (or) calculation, with statistical significance defined as p , .05. a total of 2929 questionnaires were sent out over a 4-week period in july and august 2009. of these, 812 were returned, for a response rate of 27.7%. the majority (697; 85.8%) of the respondents were female registered nurses who had received formal 3-year training, versus enrolled nurses with a shorter (2year) training and lower entry requirements. of the 812 respondents, 650 (80%) were between 36 and 55 years old, and a high proportion (463; 57%) had practiced nursing for .20 years. regarding clinical exposure, 66% (487) reported having frequent direct contact with patients. concerning part a of the questionnaire, about 60% (494) had received seasonal influenza vaccination in the preceding year. for the coming flu season, 37.5% (305) were planning to receive seasonal influenza vaccine, 40.8% (331) rejected vaccination, and 21.6% (176) were undecided. only 13.3% (108) of the respondents were considering vaccination against h1n1, with 45.4% (369) rejecting vaccination and 41.3% (335) undecided. age, experience, and frequency of patient contacts were divided into several strata for further analysis. the smaller proportion of nurses accepting h1n1 vaccination was consistent across each stratum regardless of age, experience, or frequency of patient contacts. the nature of nursing practice and frequency of patient contact were not significantly associated with the decision for vaccination (or, 1.29; 95% confidence interval [ci], 0.82-2.02). for those who either had been vaccinated in the preceding influenza season or were planning to receive seasonal influenza vaccine, the majority (.85%) believed that vaccination could protect against infection. work requirements and protecting others in the workplace from infection were less commonly cited reasons, reported by only about 50% of the respondents. for nurses who had not received vaccination in the previous year or declined vaccination in the coming year, the most frequent reason for doing was concern about side effects of the vaccine (65%-68%). this reason was cited more frequently by those who declined h1n1 vaccination (83.9%). other reasons for declining the vaccination included the perceived mild nature of influenza (26.3%-30.8%) and the belief that the vaccine could not prevent infection (55.9%-58.5%). the latter reason was less common among those who declined h1n1 vaccination. the findings are summarized in table 1 . only 108 (13.3%) of the respondents were planning to receive h1n1 vaccination when it became available. figure 1 shows the relative importance of 9 factors in the decision for considering h1n1 vaccination. the number (percentage) of nurses choosing the 3 most important factors were vaccine effectiveness (364; 44.8%), potential side effects (190; 23.4%), and illness severity (138; 17%). government policy and professional opinions were of little importance. a small proportion was concerned about the inconvenience of vaccination procedures, for example, the need to be vaccinated separately from seasonal influenza vaccine, or if 2 doses were needed. nurses that had received or were planning to receive seasonal flu vaccine had a significantly higher tendency to receive h1n1 vaccine (or, 3.73; 95% ci, 2.43-5.73 vs or, 26.89; 95% ci, 10.75-67.34, respectively). the or of the 9 factors for h1n1 vaccination was determined when each was taken as ''most important'' versus the rest. in such instance, the most significant factor was government and hospital guidelines, with an or for vaccination of 2.73 (95% ci, 1.36-5.49). frequent contact with patients, the global and hong kong risk of h1n1, vaccination schedule, severity of the disease, and professional opinion all tended to increase the or for vaccination, although these increases were not statistically significant ( table 2) . regarding the respondents' personal experience with h1n1 (part b of the questionnaire) 584 (76%) of those accepting h1n1 vaccination had never come into contact with any patients with the infection. a minority (184; 24%) needed to manage h1n1 patients at work, whereas 226 (28%) reported that their workplace handled h1n1 patients, but no contact was required. contact with h1n1 patients did not increase the or of receiving vaccination (or, 1.03; 95% ci, 0.63-1.67). there were only 8 (1%) suspected and 6 (0.75%) confirmed h1n1 cases in the study population; of these 14 cases, 6 (42.8%) were work-related. a family history of h1n1 infection was associated with a higher tendency to accept vaccination (or, 2.25; 95% ci, 0.68-7.47) ( table 2 ). figure 2 graphically presents the respondents' attitudes toward h1n1 (part c of the questionnaire). nurses who declined h1n1 vaccination tended to be less worried about becoming infected and were less inclined to perceive h1n1 as a severe infectious disease, although they basically agreed that it was highly infectious. overall, many (496; 62.4%) considered seasonal influenza and h1n1 to be of similar severity, and most agreed that h5n1 (617; 77.4%) and severe acute respiratory syndrome (sars) (772; 96.8%) were more serious than h1n1. regardless of their attitudes, most of the nurses agreed with government policies for controlling the h1n1 epidemic. based on our results, we anticipated a low uptake rate for h1n1 vaccination in nurses in hong kong. the proportion of nurses planning to receive the h1n1 vaccine was much lower in that that for the seasonal influenza vaccine (13.3% vs 37.5%), despite the similarities of the two diseases in transmissibility and clinical outcomes as reported through clinical and epidemiologic observations. 12 because influenza vaccination is not a mandatory requirement for hcws, vaccination coverage naturally hinges on the individual's willingness to get vaccinated, which in turn is dependent on the perceived risks and benefits of vaccination. our study suggests that self-protection was the main reason for receiving vaccination against both h1n1 and seasonal influenza. surprisingly, past experience with respiratory infection did not increase the likelihood of receiving h1n1 vaccination. nurses who had come into contact with patients infected with h1n1 were not more likely to receive h1n1 vaccination (or, 1.03). more nurses who had been in contact with h1n1 patients at work (44/137; 32.1%) believed that h1n1 is a minor disease compared with those who had not been in contact h1n1 patients at work (43/ 176; 24.4%). moreover, many nurses considered seasonal influenza and h1n1 to be less serious than h5n1 or sars. personal exposure to the infection was not an important factor, although the number of respondents might be too small to allow meaningful interpretation. nonetheless, our earlier studies had demonstrated a positive impact of this factor on nurses' preparedness against avian flu outbreaks. 14, 15 we explored a whole range of factors that might be associated with nonacceptance of h1n1 vaccination ( table 2) . unlike other studies on seasonal influenza vaccination, many of these potential factors did not have sufficiently strong statistical power to predict vaccination behavior against h1n1 in our nurses. those rejecting h1n1 vaccination had 2 major concerns, perceived ineffectiveness and potential adverse effects of the vaccine, cited by .50% of the respondents, consistent with previous studies. 1, 2, 16, 17 about one-third of those declining vaccination considered either form of influenza to be a mild disease. misconceptions about seasonal influenza vaccination are common among nurses, even after education programs, as reported by raftopoulos 18 and ofstead et al. 19 in particular, the purpose of vaccination to protect an at-risk population, rather than as self-protection, was hardly recognized. the factors associated with a declining h1n1 vaccination rate might well be similar to those for seasonal influenza vaccination, because many nurses considered the 2 diseases to be of similar severity. it can be argued that the perceived benefit of vaccination is easily offset by the possible, yet uncertain side effects of the h1n1 vaccine. we did not explore the cost of the vaccine as a factor in our study, because vaccination is free to all nursing staff in hong kong. an estimated 50% of the h1n1 cases in the united states are acquired in health care settings. 20 high vaccination coverage is crucial to preventing transmission of the infection. given that .40% of our survey respondents were undecided about receiving the h1n1 vaccination, the final vaccination coverage will depend on external factors that might affect their major concerns, rather than on promotion of vaccination as an effective tool to prevent infection transmission. interestingly, acceptance of seasonal influenza vaccination was a very strong predictor for acceptance of h1n1 vaccination. similar findings from an internet survey of us adults was reported by maurer et al. 21 vaccination against seasonal influenza in the preceding year was associated with an or of 26 for receiving the h1n1 vaccine in the coming season. this finding is in agreement with previous studies of seasonal influenza vaccination in hcws. [1] [2] [3] 5 thus, it has been speculated that efforts to increase seasonal influenza vaccination coverage will lead to increased h1n1 vaccination coverage. in our study, .60% of the nurses had received seasonal influenza vaccination in the previous year; however, the estimated vaccination rate for the coming flu season had dropped to 37.5%, though some 20% of the respondents were undecided at the time of the survey. if all undecided nurses subsequently received vaccination, then the proportions vaccinated against h1n1 and seasonal influenza would be quite similar, reaching $50% of the total cohort. how can vaccination coverage be improved? first, vaccination policy for hcws should be developed separately from that for the general public, given the differing concerns and priorities in the 2 populations. currently, hcws are a priority category for receiving h1n1 vaccination in hong kong, a practice also adopted in the united states and other parts of the world. 22 such an approach could be counterproductive, however, because so many hcws do not consider themselves at risk of infection. in our study, nurses demonstrated positive attitudes toward government policies on controlling the epidemic irrespective of their degree of acceptance of h1n1 vaccination. ironically, professional advice and official guidelines were relatively unimportant factors for those who rejected vaccination, a finding similar to that in a recent local study. 17 this discrepancy has arisen because policy guidelines addressing the specific needs of hcws have yet to be developed. second, vaccination as an important measure to protect vulnerable populations should be emphasized in infection control training. currently, priority populations for h1n1 vaccination include elderly persons, pregnant women, and persons with chronic disease. the purpose of offering vaccination to these latter groups is to prevent disease and reduce morbidity and mortality. theoretically, vaccination of hcws could serve a dual purpose of occupational safety and infection control, the latter to reduce the incidence of nosocomial infection. in our study, those accepting vaccinations perceived h1n1 or seasonal influenza vaccination not as an infection control measure, but simply as a means of self-protection. rectifying this prevailing attitude should be considered through policy and educational strategies. third, combining the human h1n1 and seasonal influenza vaccines in a single vaccination program may help improve the uptake rate. admittedly, the coverage of seasonal influenza vaccination has remained suboptimal, even though the percentage of nurses accepting the vaccination is much higher than that for h1n1 vaccination. incorporating the h1n1 vaccine in the seasonal influenza regimen, as advocated for the southern hemisphere in the coming year, could boost the coverage to that for the seasonal influenza vaccine. 23 however, this would still not be good enough if the objective of vaccinating hcws is to control transmission, for which a near-100% coverage is the goal. our study has some limitations. first, only a small number of nurses were represented in the survey. the total number of registered nurses and enrolled nurses in hong kong was 37,447 as of december 2008. 24 for practical reasons, it was impossible to include all nurses due to limited resources and the lack of a uniform survey platform. second, some 30% of the nurses in our cohort did not have frequent patient contact, a factor that should be noted when extrapolating results to the health care profession at large. we have not been able to categorize the population according to the nature of the workplace. it would be interesting to compare the responses in nurses with different jobs, such as those in outpatient clinics, hospitals, and nonclinical settings. third, most of the responding nurses were mature and highly experienced, characteristic of members of the nursing associations surveyed. younger nurses and those with less experience might not have been captured. moreover, the use of a mailin survey might have caused some bias in the responses. it could be argued that those who took time to return the questionnaire were probably more ready to express their thought and opinions. finally, nursing culture varies across countries, and so our results might not be applicable to other places. self-reported influenza vaccination rates among health care workers in a large health system influenza vaccination among primary healthcare workers influenzavaccination coverage among hospital personnel over three consecutivevaccination campaigns influenza vaccination of healthcare workers in the united states influenza vaccination of healthcare workers: a literature review of attitudes and beliefs nurses' attitudes and beliefs about influenza and the influenza vaccine: a summary of focus groups in alabama and michigan barriers to influenza vaccine acceptance: a survey of physicians and nurses pneumonia and respiratory failure from swine-origin influenza a (h1n1) in mexico severe respiratory disease concurrent with the circulation of h1n1 influenza emergence and pandemic potential of swine-origin h1n1 influenza virus emergence of a novel swine-origin influenza a virus (s-oiv) h1n1 virus in humans the 2009 h1n1 influenza outbreak in its historical context triplereassortant swine influenza a (h1) in humans in the united states impact of sars on avian influenza preparedness in healthcare workers impact of severe acute respiratory syndrome and the perceived avian influenza epidemic on the increased rate of influenza vaccination among nurses in hong kong which determinants should be targeted to increase influenza vaccination uptake among health care workers in nursing homes? willingness of hong kong healthcare workers to accept prepandemic influenza vaccination at different who alert levels: two questionnaire surveys attitudes of nurses in greece towards influenza vaccination influenza vaccination among registered nurses: information receipt, knowledge, and decision making at an institution with a multifaceted educational program novel influenza a (h1n1) virus infections among health-care personnel-united states does receipt of seasonal influenza vaccine predict intention to receive novel h1n1 vaccine: evidence from a nationally representative survey of us adults healthcare workers should get top priority for vaccination against a/h1n1 flu, who says responding to the renewed h1n1 pandemic we thank cecilia so, hong kong nurses general union, nurses branch, and enrolled nurses branch of the hong kong chinese civil servants association, and all members of the 3 associations who participated in this survey. the results presented in this article do not reflect the views of the associations that facilitated the administration of the research. we also thank david sorrell for general advice. key: cord-330666-puhijixa authors: carrico, ruth m.; coty, mary b.; goss, linda k.; lajoie, andrew s. title: changing health care worker behavior in relation to respiratory disease transmission with a novel training approach that uses biosimulation date: 2007-02-02 journal: am j infect control doi: 10.1016/j.ajic.2005.12.013 sha: doc_id: 330666 cord_uid: puhijixa background: this pilot study was conducted to determine whether supplementing standard classroom training methods regarding respiratory disease transmission with a visual demonstration could improve the use of personal protective equipment among emergency department nurses. methods: participants included 20 emergency department registered nurses randomized into 2 groups: control and intervention. the intervention group received supplemental training using the visual demonstration of respiratory particle dispersion. both groups were then observed throughout their work shifts as they provided care during january-march 2005. results: participants who received supplemental visual training correctly utilized personal protective equipment statistically more often than did participants who received only the standard classroom training. conclusion: supplementing the standard training methods with a visual demonstration can improve the use of personal protective equipment during care of patients exhibiting respiratory symptoms. health care personnel are at risk for exposure to a variety of infections during the routine performance of their job responsibilities. despite these risks, compliance with protective equipment has remained suboptimal. 1 the safety of emergency department (ed) personnel, often the first to encounter an ill patient, is an important area to target for improvement. the risk factors for those individuals include the emergent nature of the care provided and the unknown circumstances that initially led to the patient's utilization of health care. 2 despite the emphasis on standard precautions training for health care workers (hcws), the consistent use of personal protective equipment (ppe) remains poor. 3, 4 various descriptions and analyses of the 2002-2003 severe acute respiratory syndrome (sars) outbreak reported lack of basic preemptive infection prevention and control strategies. as the outbreak grew, attention was paid to use of protective equipment, including respiratory protection, as symptomatic patients were identified. the experiences of hcws confronted with suspected or confirmed sars cases revealed an often inadequate and incorrect use of ppe. 5, 6 a fundamental flaw in the preventive process seemed to involve failure to recognize quickly the key signs, symptoms, or risks that might have led to the early implementation of protective equipment. although there is little research concerning changing hcw behavior when providing care for patients with respiratory illness, there was some evidence from the sars outbreak that pointed toward the benefits of training programs and availability of adequate ppe. 7 the workplace practices identified as problematic during the sars epidemic mirror those identified by jagger et al at the international healthcare worker safety center of the university of virginia. jagger et al's work has focused on injuries and exposures involving blood and body fluid exposures among hcws. in 2001, as part of the epinet surveillance program, 8 a total of 463 blood-body-fluid exposures were reported from 49 participating health care facilities. of these exposures, over 13% occurred in the ed. less than 10% of the exposed hcws reported wearing appropriate eye protection, and fewer than 20% reported wearing some sort of mask or other facial barrier. 9 clearly, the need still exists for effective training techniques to promote the use of ppe as a way to minimize such workplace exposures. traditional infection prevention and control training for hcws has involved a review of the occupational safety and health administration (osha) bloodborne pathogens training, 10 as outlined in the current centers for disease control and prevention (cdc) isolation guidelines, 11 with emphasis on transmission-based precautions. when we conducted an informal telephone interview with infection control professionals (icps) from 10 us hospitals chosen at random, results indicated that this type of training involved a classroom setting (80%) and/or written handouts (20%). a pretest and posttest process typically assessed competency. none of the interviewed hospitals reported the consistent inclusion of an observational component in their training or subsequent assessments. much of the existing research and education involves exposures to bloodborne pathogens; very little involves respiratory pathogens. the research does, however, enforce the concepts of disease transmission and identifies the lack of consistent protective activities used by health care personnel. [1] [2] [3] [4] the risks involved in respiratory pathogen transmission have been included in the concept of ''cough etiquette'' outlined in the draft version of the impending cdc draft guideline for isolation precautions: preventing transmission of infectious agents in healthcare settings, 2004. 12 it is important to identify innovative methods that will impact practice and result in procedural changes that will better protect the care provider. developing new methods that can change the behavior and increase the appropriate use of ppe is a challenge. this pilot study evaluated a novel training approach for hcws to use ppe when encountering patients who have known or suspected respiratory illnesses. the training approach involved the use of a human patient biosimulator to visually demonstrate respiratory disease transmission. the effectiveness of the visual demonstration was assessed by comparing the ppe-specific knowledge, attitudes, and skills of ed registered nurses (rns) who received the demonstration to those who only received the standard disease transmission training. the study hypotheses were as follows: (1) the standard disease transmission training will result in an increase in knowledge among rns, and (2) the additional use of a visual demonstration would result in significant improvement in appropriate ppe use among hcw beyond the improvement produced by the standard training methods. this pilot project involved the use of the patient biosimulator (medical education technologies, inc. [meti], sarasota, fl) to demonstrate particle dispersal during a cough. when the biosimulator ''coughed,'' fluorescent powder was dispersed into the air, allowing the study subject to visualize the impact to themselves and the environment. the study subjects were able to see the particles move directly from the patient to the air and contaminate the environment as well as the subject's physical person (fig 1) . the effectiveness of ppe was demonstrated using a black light that showed areas of fluorescent powder contamination and areas in which ppe provided a barrier, thereby preventing contamination. we used pre-/posttest knowledge assessments and observations of hcw-patient interactions to evaluate the impact of the visual demonstration of respiratory disease transmission on ppe use by hcws. the study was conducted during the peak of the 2005 influenza season (january to march) to ensure that the hcws could be observed interacting with the greatest number of patients with respiratory symptoms. the study was conducted at a university medical center in a large metropolitan city. training sessions and observations took place in the ed. initially, 22 rns were recruited into the study; 2 subjects withdrew from the study following job transfers. an effort was made to recruit an equal number of day shift (7 am to 7 pm) and night shift (7 pm to 7 am) nurses into the study. the university hospital institutional review board approved the study. eligible rns were identified by the ed nurse manager and were informed of the study during scheduled staff meetings and by posted flyers. eligible rns were those nurses who were employed by the hospital; therefore, mobile or per diem nurses were excluded. during the staff meetings, the investigators provided a brief overview of the study, answered questions, and determined staff members' willingness and eligibility to participate in the study. the rns who agreed to participate were provided with a consent form to sign. after the consent form was signed, all subjects were scheduled to attend classroom training. this training focused on mechanisms of disease transmission, standard precautions, and appropriate use of ppe. the 20 subjects were randomly assigned to either the intervention group or the control group. the intervention group received classroom training plus biosimulated visual training, and the control group received classroom training only. after group assignments were made, a colored sticker was placed on the subjects' identification badges to indicate participation in the study. observers with experience in the education and training of health care personnel were trained to recognize and evaluate the use of ppe by study participants during real patient interaction. the observers were blinded to the subjects' group assignment. a work schedule was provided to the observers to allow equal opportunity for evaluation on both shifts throughout the observation period. the study was designed to continue until a minimum of 10 patient-subject interactions were observed for each study participant or until the ed activity indicated that the presentation of symptomatic patients had declined to a point that observation opportunities were minimal. personal handheld computers were used for data entry by the observers. the investigators developed software, and training was provided to the observers. use of the handheld data collection device allowed the observers to collect and record information in an unobtrusive manner and minimize data entry errors. written scenarios and monitoring of real-time nursepatient interactions were observed in an effort to promote interrater reliability between the 2 observers. the 2 observers participated in specific education and evaluation sessions held prior to the study, during the study, and after completion of the study. sessions were held with both observers together as well as separately. scenarios were presented to determine the ability of each observer to identify the care setting (eg, triage, assessment) specific types of ppe (eg, mask vs n95 respirator), and symptoms exhibited by the patient (eg, temperature readings, cough, rhinitis). during all reviews, both observers consistently demonstrated 100% accuracy. data were collected at 3 points in time: (1) participants completed a knowledge assessment prior to the classroom training. the pretest phase included an assessment of subject's knowledge of respiratory pathogen transmission as well as standard precautions; (2) once classroom training was completed, the subjects retook the knowledge assessment; and (3) observations began after the posttest had occurred. observations of the subjects' use of ppe were made in the weeks immediately following the completion of training. a patient-subject interaction was considered appropriate for study inclusion if the observers noted that the patient exhibited respiratory symptoms (ie, cough and/or fever). if the patient-subject interaction was appropriate, the observers evaluated the subject's behavior with regard to ppe use. the observers also recorded the patient's symptoms, the time and location of the care, and the care that was being provided. type of care provided was coded as triage, physical assessment, invasive procedure, noninvasive procedure, and resuscitation event. knowledge related to respiratory pathogen transmission and standard precautions guidelines were measured by a questionnaire developed for this study. evaluations of the patient-subject interaction by the 2 trained observers included the date/time of observation, presenting diagnosis, procedure(s) performed during the observation episode, presence of respiratory symptoms, patient cooperation as related to each procedure, and a list of all ppe items used or worn by the observed hcw. the opportunity for the observer to make special comments that may impact the use of ppe (eg, if the patient is masked during the observation episode) was included in the data collection form. table 1 . the 2 groups were found to be similar on most demographic variables. the age range was 23 to 56 years with a mean age of 38 years. the 2 groups were primarily female (95%), with slightly less than half (48%) having a college or graduate degree (bachelor's degree or master's degree in nursing). both the intervention group and the control group completed standard classroom training designed to provide text-based information about disease transmission. the preclassroom training knowledge assessment indicated no difference between the intervention and control groups (t(19) = 1.11, p = .28). the average pretest score was .67 (sd = .12) for the control group and .62 (sd = .09) for the intervention group. the 2 groups also did not differ significantly on the postclassroom training assessment (t(19) = 1.22, p = .24). the average posttest score for the control group was .81 (sd = .17) and .72 (sd = .18) for the intervention group. combining the scores of both groups yielded a pretest score of .64 (sd = .11) and a posttest score of .76 (sd = .17). overall, both groups showed a a total of 114 observations were recorded: 56 for the control group and 58 for the intervention group. of these, 35 involved more than 1 observation on a single patient. in an effort to ensure independent observations, 1 observation was randomly selected from each patient to be included in the final data set. this was done to prevent multiple observations of a single patient for whom ppe was used or not used during each patient interaction. in the final dataset, there were 84 observations, with 42 in each group. cough, fever, rhinitis, and/or sneezing were considered conditions in which ppe was required. the intervention group did not differ significantly from the control group on the proportion of patients with symptoms requiring ppe use (86% vs 93%, respectively, [fisher exact test, p = .16]). table 2 shows the breakdown of protective equipment used by study participants stratified by group. interestingly, rns in both groups routinely elected to place masks on the patients instead of on themselves. a mask, used on the rn and/or the patient, was considered to be appropriate ppe when the patient condition included fever, cough, sneeze, and/or rhinitis. self-use of a mask did not differ between the control and intervention groups (fisher exact test, p = .60). although use of a mask on the patient occurred more frequently in the intervention group, it was not significant (fisher exact test, p = .08). upon analysis of data, the practice of nurses masking patients was an unexpected finding. it was then decided to aggregate self and patient mask use into a single dichotomous variable: ppe mask use. when use of ppe (self-use of mask and placement of mask on patient) was dichotomized into ''yes'' or ''no'' and was cross-tabulated with group assignment, analysis comparing use of ppe between control and intervention groups indicated that subjects who received the visual training demonstrated use of ppe more often (74% vs 53%, respectively). given the exploratory nature of the study and the unidirectional hypothesis that the visual demonstration would improve ppe use, statistical significance for this hypothesis was evaluated as a 1-tailed distribution test (a = .05). a fisher exact test was performed to determine whether the visual demonstration increased appropriate ppe use relative to the standard training alone. results are shown in table 3 and indicate that the standard training plus biosimulation significantly increased the use of ppe for patients with respiratory symptoms (p = .04). the literature that addresses ppe use among hcws continues to stress the need for education as a means of improving safety practices. [1] [2] [3] [4] [5] [6] [7] this study showed, however, that traditional education is not necessarily the sole or even key factor in improving ppe use. two basic components were addressed in this pilot project. the first involved the increase in knowledge regarding disease transmission using a traditional didactic training process. the second component investigated whether a biosimulated, visual demonstration of particulate transmission would result in increased ppe use. traditional classroom training did, indeed, make a significant difference in pre-and posttraining knowledge. the addition of a visual component to training emphasized the personal risk of the individual hcw. direct observations showed that the subjects trained using this visual approach appropriately used ppe more often than those subjects whose training did not include this visual component: 74% versus 53%, respectively. therefore, these results suggest that use of the biosimulator and visual training is an important new approach for learning in the health care setting. this type of learning allowed the hcw to see the impact of disease transmission as opposed to simply hearing about it through traditional didactic education. in addition, the components of this visual demonstration built on the principles of adult learning. teaching occurred within the context of work experience, thereby making the learning relevant to the individual. feedback from the subjects in the intervention group reinforced the value of the visual component of training. several staff commented that they recognized environmental or personal contamination when they could see the blood or other fluids they encounter during emergency procedures but admitted that their use of protective strategies, including ppe, was less than ideal. every subject trained in the intervention group remarked on the impact they felt the visual demonstration had on their individual practice. the major limitation of this pilot study was the small size of the sample. although many results demonstrated significance, the question remains whether or not the results are generalizable. repeating this study on a larger scale could help answer that question. the logistics involved in unobtrusively observing practice and working around nurses who were not involved in the study made planning and implementation a difficult task. another issue of concern was our inability to ascertain the influence of the organization on the use of safety practices, including use and selection of ppe. if this study were repeated and involved multiple sites, the culture of safety and its impact could be assessed. with the availability of inexpensive computer technology in recent years, simulation technology has blossomed, especially in the field of medicine, in which applications range from scientific modeling to clinical performance appraisal in the setting of crisis management. much of the initial work with human patient biosimulators, or use of a simulation ''dummy,'' has been done by anesthesiologists as part of their road toward medical error reduction. biosimulators are now used in university medical centers across the country to assist and improve the learning of residents, medical students, nursing students, and employed hcws. the benefits of simulation technology in medical training include improvements in cardiovascular examination skills, increased precision in surgical technical skills, and acquisition and retention of knowledge compared with traditional modes of teaching (eg, lectures). [13] [14] [15] [16] [17] [18] although there has been significant knowledge and experience gained through simulation in the area of medical education, there has been a lack of research concerning the use of simulation as a method of enhancing performance involving respiratory disease transmission. developing an improved model for training hcws that demonstrates a significant improvement in behavior regarding ppe use has the potential to protect the millions of hcws that currently practice in health care settings. reducing the respiratory exposures because of influenza and preventing the repeated scenarios identified during the sars 2003 global epidemic may also prevent the unnecessary illness/deaths of hcw because of inadequate or inappropriate use of respiratory ppe. successful demonstration of improvements could change the way hcw education is conducted throughout a variety of environments, not simply the ed. furthermore, this type of education could be used in other professional disciplines, including physician, therapist, and administrative training. epidemiology and prevention of blood and body fluid exposures among emergency department staff compliance with universal precautions among emergency department personnel: implications for prevention programs risks for exposure to and infection with hiv among health care providers in the emergency department variables influencing worker compliance with universal precautions in the emergency department lack of sars transmission among healthcare workers, united states investigation of a nosocomial outbreak of severe acute respiratory syndrome (sars) in toronto, canada the bc interdisciplinary respiratory protection study group. protecting health care workers from sars and other respiratory pathogens: organizational and individual factors that affect adherence to infection control guidelines occupational safety and health administration. occupational exposure to bloodborne pathogens: final rule. 29 cfr part 1910.1030 guideline for isolation precautions in hospitals. the hospital infection control practices advisory committee cdc cdc draft guideline for isolation precautions: preventing transmission of infectious agents in healthcare settings patient safety and simulation-based medical education simulation technology for health care professional skills training assessment educating health professionals to respond to bioterrorism practical health care simulations recognizing biothreat diseases: realistic training using standardized patients and patient simulators the authors thank the observers, david walsh, bs, and jonathan carrico, bs, for their commitment to the project and attention to excellence and the hospital emergency department staff for their support and participation. the authors have made available to the readers a visual component to this article. readers may visit the following web site to see a brief video clip (there is no sound with this clip): http://www.louisville. edu/television/cough.asx key: cord-291742-donflx7w authors: khan, raymond m.; al-juaid, maha; al-mutairi, hanan; bibin, george; alchin, john; matroud, amal; burrows, victoria; tan, ismael; zayer, salha; naidv, brintha; kalantan, basim; arabi, yaseen m. title: implementing the comprehensive unit-based safety program model to improve the management of mechanically ventilated patients in saudi arabia date: 2018-09-05 journal: am j infect control doi: 10.1016/j.ajic.2018.06.022 sha: doc_id: 291742 cord_uid: donflx7w background: ventilator-associated events are common in mechanically ventilated patients. they are associated with more days on mechanical ventilation, longer intensive care unit (icu) stay, and increased risk of mortality. theoretically, interventions that prevent ventilator-associated events should also reduce associated morbidity. we evaluated the comprehensive unit-based safety program approach to improve the care of mechanically ventilated patients. methods: all mechanically ventilated patients admitted to the icu between october 1, 2015, and october 31, 2016, were prospectively monitored for the development of ventilator-associated events according to the national healthcare safety network criteria. a process care bundle (endotracheal intubation with subglottic suctioning, head-of-bed elevation ≥30°, target sedation scores, daily spontaneous awakening trials, spontaneous breathing trials), daily delirium assessment, and an early mobility protocol were instituted. the bundle compliance, ventilator-associated events rates, icu length of stay, and mortality rate were noted. the database allowed viewing of current rates, trends, and averages of all participating sites. results: in the study period, 2,321 patients were admitted to the icu, and 1,231 required mechanical ventilation (10,342 ventilator days). there were 115 ventilator-associated events: 82 ventilator-associated conditions, 15 infection-related ventilator-associated conditions, and 18 possible cases of ventilator-associated pneumonia. the icu mortality rate was 13.3%, compared with 28.7% for those mechanically ventilated patients with ventilator-associated events (p = .0001). there was increased compliance for spontaneous awakening trials (51.5%-76.9%, p = .0008) and spontaneous breathing trials (54.2%-72.2%, p = .02) and a decrease in infection-related ventilator-associated conditions (4.2-3.5 per 1,000 days), possible cases of ventilator-associated pneumonia (2.1-1.7 per 1,000 days), icu mortality (45.3%-19.1%, p = .045), and ventilator-associated events associated mortality rates (33.3%-8.3%, p < .37). physical therapy participation and mobility were 60.8% and 26.4%, respectively. conclusion: the implementation of a multipronged program like the comprehensive unit-based safety program could improve the care processes and outcomes of mechanically ventilated patients. in 2004, the institute for healthcare improvement (ihi) 100,000 lives campaign introduced the concept of a "care bundle" for the prevention of ventilator-associated pneumonia (vap). 1 a care bundle identifies a set of key interventions that, when implemented together as a best practice approach, are expected to improve patient outcomes. 2 in recent years, approaches to the care of mechanically ventilated patients have evolved from fixating only on vap prevention to focusing on a more comprehensive strategy based on the recent finding of benefit from the combined approach of the abcde bundle (awakening and breathing trial coordination, delirium management and early mobilization) 3 and the wake up and breathe collaborative trial. 4 although previous improvement initiatives used vap rates as the primary outcome measure, it has been increasingly recognized that mechanical ventilation (mv) causes harm beyond just vap. hence, wider outcome measures were needed to determine the value and success of safety programs. the centers for disease control and prevention, together with several critical care societies, convened a group to address the limitations of the national healthcare safety network definition of injury caused by mv, and they proposed a new approach in 2013. 5 besides vap, the new algorithm uses objective criteria for the diagnosis of ventilator-associated events and conditions and infection-related ventilator-associated complications. this approach thereby broadens the definition of harm suffered by ventilated patients beyond pneumonia to include pulmonary edema, atelectasis, and acute respiratory distress syndrome. 6 the comprehensive unit-based safety program (cusp) approach was developed by patient safety researchers at the johns hopkins hospital, baltimore, maryland. 7 cusp is designed to improve teamwork and safety culture and to guide organizations to learn from mistakes by using a validated and structured framework. 8 cusp involves a repetitious process that trains a multidisciplinary team about the science of safety, asking them to identify defects, learn from them, implement improvement tools, and establish a partnership with senior leaders. 9 key components include identifying evidence-based interventions that improve the outcomes of interest, converting these interventions into behaviors, placing value on the wisdom of frontline staff, and empowering frontline staff to be actively involved in safety improvements. the cusp intervention has achieved great success in reducing vap, central lineàassociated bloodstream infections, catheter-associated urinary tract infections, surgical care complications, mortality, and associated costs. 10, 11 our hospital's infection control and intensive care departments implemented a vap prevention program in 2003, which led to the reduction of vap rates from 19.1 to 0 per 1,000 ventilator days in 2015. 12 despite our success in reducing the vap rates, our data indicated that intensive care unit (icu) length of stay (los) (9.8 vs 8.5 days) and mortality rates (36% vs 28.7%) were both higher in the post-vap prevention bundles compared with the pre-vap prevention intervention group, 12 implying that merely decreasing the rate of vap was not enough. we needed to implement other strategies to optimize patient care to improve outcomes. we joined the johns hopkins armstrong institute comprehensive unit-based safety program for mechanically ventilated patients and ventilator-associated pneumonia (cusp 4 mvp-vap) project in october 2015 with the objective of improving the care delivery process and reducing the mortality of our mechanically ventilated patients. this article describes the impact of implementing the cusp 4 mvp-vap project on patient care in our icus at the ministry of national guard health affairs in riyadh. this was a prospective quality improvement and patient safety study to describe the impact of implementing the cusp 4 mvp-vap in a cohort of patients in our icus. this improvement project was performed at king abdul aziz medical city in riyadh, saudi arabia, for all adult patients who received invasive mv in the icu between october 1, 2015, and october 31, 2016. the icu had 60 beds and was covered by onsite board-certified intensivists 24 hours per day, 7 days per week, with a nurse-to-patient ratio of approximately 1:1 and a respiratory therapist-to-patient ratio of approximately 1:5. the hospital was a 1,000-bed tertiary-care center accredited by the joint commission international, with an active infection prevention and control program that collaborated with the icu medical and nursing staff to ensure the implementation and monitoring of infection control practices. the institutional review board and king abdullah international medical research center ethics committee of national guard health affairs, riyadh, saudi arabia, approved this study and waived the requirement for informed consent. a multidisciplinary cusp 4 mvp-vap team was created in september 2015 to implement evidence-based practices for all mechanically ventilated patients. the group was led by an intensivist but included other physicians, nurses, respiratory therapists, physical therapists, infection control practitioners, and quality management personnel. the team monitors (nurses and research coordinators) were trained on data collection and monitored compliance on a daily basis. they reviewed the electronic charts of all patients on mv in the icu daily. the implementation of each care process bundle element, along with the confusion assessment method for the icu (cam-icu) score and the maximum level of mobility for that day were recorded on a standard data collection form and entered into the johns hopkins armstrong institute database, which generated a compliance rate for our hospital. this compliance rate was compared with those of other institutions in the project, so that we could benchmark our performance. if a component of the bundle was not performed, the inspectors used this moment to elucidate any barriers to the implementation of the particular element. the first month (october 2015) was considered the baseline data point. we defined a ventilator-associated condition (vac) as an increase in fio 2 0.2 or positive end expiratory pressure (peep) 3 cm h 2 o sustained for 2 calendar days in a patient on mv for >2 days with a baseline period of stability or improvement, defined by 2 calendar days of stable or decreasing daily fio 2 or peep values. 13 an infection-related ventilator-associated complication (ivac) occurred on or after 3 days of mv when a patient met the criteria for a vac plus both of the following: temperature >38°c or <36°c and white blood cell count 12,000 or 4,000 cells/mm 3 , as well as a new antimicrobial agent(s) started and continued for 4 calendar days. 13 a possible vap (pvap) occurs in a patient with the criteria for an ivac and 1 of the following: positive culture meeting quantitative or semiquantitative thresholds from endotracheal aspirate (10 5 colony-forming units [cfu]/ml), bronchoalveolar lavage (10 4 cfu/ml), lung tissue (10 4 cfu/g), or protected specimen brush ( 10 3 cfu/ml); purulent respiratory secretions (>25 neutrophils and <10 squamous epithelial cells per low-power field plus organism identified from sputum, endotracheal aspirate, bronchoalveolar lavage, lung tissue, protected specimen brush); or organism identified from pleural fluid, lung histopathology, legionella tests, or diagnostic test on respiratory secretions for influenza virus, respiratory syncytial virus, adenovirus, parainfluenza virus, rhinovirus, human metapneumovirus, or coronavirus. ventilator-associated events (vaes) are the sum of vac, ivac, and pvap. all patients on mv were reviewed prospectively and independently by 2 physicians who confirmed the diagnosis. 13 the incidence of vae, vac, ivac, and pvap was expressed as cases per 1,000 ventilator-days. the project had 3 arms: daily care process, early mobility, and low tidal volume ventilation. participation could be in 1, 2, or all 3 of the arms (fig 1) . our hospital selected daily care process and early mobility, because low tidal volume ventilation was already a standard practice in our icus for all patients on mv. i. daily care process a. endotracheal tube with subglottic suctioning (sub-g eet) all patients anticipated to need mv for >48 hours were intubated with a taperguard evacuation oral tracheal tube (covidien, mansfield, ma). the data collectors inspected patients for the presence of sub-g eet when indicated and documented whether the subglottic drainage lumen was connected to the wall suction at the appropriate intermittent negative pressure. 12 b. head of bed (hob) 30°t he hospital was equipped with hill-rom hospital beds (hill-rom, chicago, il). the angle of the hob was measured with an electronic device or built-in protractor present on the bed. elevation of the hob was the default order for all patients on mv. exceptions were hypotension; unstable physiological status; low cardiac index; recent cervical, thoracic, or lumbar surgery or instability; ventricular assist device; intra-aortic balloon pump; open abdomen; and patient refusal. 12 this element required that the data collector directly observe the angle of the hob. a nurse-led sedation vacation protocol was implemented that allowed the nurse to stop all sedation at 8:00 a.m. if the patient fulfilled certain criteria. 12 the sat was continued until either the patient was agitated or fully awake and could be assessed for delirium. for this element, the data collectors asked the bedside nurse whether sedation was interrupted. they then reviewed the patient's daily flow sheet to confirm the nurse's statement. if the chart did not reflect sedation interruption, then this bundle was considered noncompliant. d. sedation-minimized (sedation score target) sedation orders were entered via a standardized computer order set, with dosage adjusted based on the patient's weight and renal and hepatic functions. in addition, a target sedation score (richmond agitation-sedation scale [rass]) had to be assigned to the patient by the physician before the order could be completed. the targeted rass was addressed daily in rounds, and the nurse's documentation was examined to determine whether the patient's actual sedation score matched the planned target. a ventilator weaning protocol was drafted that allowed respiratory therapists to wean all patients on mv starting at 9:00 a.m., 1 hour after the sedation was held. patients who met the following criteria were weaned to pressure support ventilation: awake or off sedation with rass 3 or for >1 hour spontaneous inspiratory efforts oxygen saturation >88% the spontaneous breathing trial was conducted by placing the patient on pressure support (5-8 cm h 2 o) with or without 5 cm h 2 o peep. both the patient's icu flow sheet and respiratory therapist's notes were monitored to assess this element. the cam-icu advocated by the society of critical care medicine was used to evaluate for delirium. in our hospital the assessment tool was translated into arabic, and, after a validation process of several plan-do-study-act cycles, staff were trained to perform this appraisal. the cam-icu score was recorded at 10 a.m. daily and documented 7 : p if the patient is positive for delirium based on cam-icu assessment n if the patient is negative for delirium based on cam-icu assessment uta if unable to assess (ie, rass = ¡4 or ¡5) x if cam-icu assessment was not completed nk if cam-icu was completed, but results are not known nk was also used if it was not known whether the cam-icu was performed ii. early mobility a. mobility-tailor goals to maximize mobility all patients admitted to the icu had standing orders for physical therapy (pt) and occupational therapy as part of the admission order sets. the level of mobility (0 to 8) was recorded: 0: passively rolled or exercised; 1: transfer from bed to chair without standing; 2: sitting in bed/exercising in bed; 3: sitting at edge of bed; 4: standing with or without assistance; 5: transfer from bed to chair with standing; 6: marching in place; 7: walking at least 4 steps; and 8: unknown what level of activity occurred. additionally, any perceived barrier to achieving a higher level of mobility was documented. there were bimonthly meetings among the cusp team and monthly webinars with the armstrong institute. frequencies and percentages were used for categorical variables, whereas means with standard deviations were presented for continuous variables. the fisher exact test was used to evaluate differences between categorical variables, and the t test was used to evaluate differences between continuous variables. comparisons for mortality, los, and mv days were made, with the first month (october 2015) used as the base line. the unadjusted risk of death from developing a vae was compared using the fisher exact test; for those patients receiving mv who did not develop a vae. p < .05 was considered statistically significant. during the study period 2,321 patients were admitted to the icu; 1,231 (53%) required mv, with 1,399 episodes of mv and 10,342 ventilator days. there were 115 vaes, of which 82 were vacs, 15 ivacs, and 18 pvaps (table 1, fig 2) . the overall icu mortality rate was 13.3% compared with 28.7% for those with development of a vae (p = .0001). the icu mortality rate for mechanically ventilated patients decreased from 32.8% to 19.1% (p = .045), whereas the mortality rate associated with vaes decreased from 33.3% to 8.3% (p = .37) over the study period (fig 3) . there were significant increases in mv days and icu los for patients with vaes ( table 1) . the mean care bundle compliance for all the elements was 82.8%. the compliance rates for endotracheal intubation with subglottic suctioning, hob elevation 30°, daily sats, and sbts were 79.7%, 98.6%, 76.95%, and 72.2%, respectively. the greatest improvement was seen in sats, which increased from 51.5% in november 2015 to 76.9% in october 2016 (25.49% absolute increase, p = .0008). this was followed by sbts, which increased from 54.2% to 72.2% (18% absolute increase, p = .02). the compliance of endotracheal intubation with subglottic suctioning decreased by 16.8% (p = .0006), whereas for hob it remained around 99% throughout the project (fig 4) . the target rass was achieved in 52.8% of mechanically ventilated patients, whereas 40.6% had a rass of ¡1 to +1. however, 90.5% of patients had their sbt done off sedation, and the percentage of mechanically ventilated patients without sedation increased from 36.1% to 50.9% (p = .06). the delirium assessment compliance rate was 97.3%, with 82.8% reporting a negative cam-icu. the percentage of incorrectly reported cam-icu scores was 38.3%, which significantly decreased from 67.5% (november 2015) to 10.7% (october 2016) (p = .0001). the pt and occupational therapy participation rates were 60.8% and 26.4%, respectively. only 1.8% of mechanically ventilated patients were moved from bed to chair. the most frequent level of mobility achieved was 0 (passively rolled or exercised [83.2%]). the other levels were 1 (transfer from bed to chair without standing . the most common perceived barriers to mobilization were the following: patient weakness (20%), hemodynamic instability (18.6%), low rass on sedation (15.6%), low rass off sedation (11%), and the patient labeled comfort care (9.5%). however, the most documented adverse event was circulatory or respiratory instability (22.7%). in our study the implementation of the multifaceted cusp 4-mvp vap approach resulted in an increase in sat (51.5%-76.9%, p = .0008) and sbt (54.2%-72.2%, p = .02) compliance; an increase in the number of mechanically ventilated patients without sedation (36.1%-50.9%, p = .06); and a decrease in ivacs (4.2-3.5 per 1,000 mv days), pvap (2.1-1.7 per 1,000 mv days), icu mortality rates (45.3%-19.1%, p = .045), and vae mortality rates (33.3%-8.3%, p < .37). finally, we found that our compliance with pt participation and mobility were suboptimal. in 2013, the centers for disease control and prevention replaced their vap surveillance definitions with vae objective criteria, in response to a series of concerns about the traditional vap definitions, including their complexity, subjectivity, burden on surveyors, lack of comparability between institutions, narrow focus, and limited association with adverse outcomes. 14 furthermore, vap did not consistently identify patients at increased risk for poor outcomes, and interventions that reduced vap rates often had no effect on patient-centered outcomes, such as duration of mv or hospital mortality. 15 this is demonstrated in our previous vap prevention project, in which, in spite of the rate of vap decreasing from 19.1 to 0 per 1,000 ventilator days, the days on mv remained unchanged, whereas the icu los and icu and hospital mortality rates all significantly increased in the postbundle implementation group. 12 the failure of most vap prevention strategies to yield better outcomes for ventilated patients raises the question of whether vap is the best target to drive surveillance and safety prevention programs, because quality improvement initiatives must focus on identifying and preventing objective complications that are unambiguously associated with poor outcomes. 15 thus the explicit intent of the a vae criteria was to broaden the focus of quality surveillance beyond just pneumonia. klompas et al, 16 in a retrospective study of 20,356 episodes of mv found that vaes were associated with more days to extubation (relative risk, 3 18 our data also demonstrated that vaes are associated with increased mechanical ventilator days, icu los, and icu mortality, highlighting the point that a vae appears to be a clinically important event. the synthesis of the vae criteria has created a new opportunity for health care facilities to reexamine their approach to preventing complications and improving outcomes of mechanically ventilated patients. vae surveillance has a quality metric character and appears to identify potential safety opportunities to improve care and outcomes for patients. 19 theoretically, interventions most likely to prevent vaes are those that help patients avoid intubation, minimize the duration of mv, or prevent the conditions that most commonly trigger a vae (pneumonia, volume overload, acute respiratory distress syndrome, and atelectasis). 20 use of high-flow nasal oxygen for hypoxemic and noninvasive ventilation for hypercapnic respiratory failure may avoid intubation. minimizing sedation, performing daily coordinated sats and sbts, and perhaps early mobility are strategies to decrease the duration of mv. strategies to prevent pneumonia, volume overload, acute respiratory distress syndrome, and atelectasis include hob elevation, conservative fluid management, conservative blood transfusion thresholds, low tidal volume ventilation, and early mobility. 14 these interventions are consistent with the best care practices advocated by the abcdef bundle, the surviving sepsis campaign, and the society for healthcare epidemiology of america's recommendations to prevent vap. [21] [22] [23] growing data support that implementing and optimizing these practices can lower vae rates and improve patient outcomes. the cusp 4mvp-vap project was engendered to continue this wider focus of implementing an evidence-based practice bundle while caring for mv patients. our study showed that sat and sbt rates were 76.5% and 76%, respectively. this is similar to data published from 56 icus in maryland and pennsylvania with 69,417 ventilated patient-days in which compliance with sat and sbt was 77.5% and 71%, respectively. 24 our icus have a nurse-led sedation vacation protocol and target sedation scores for all sedated patients. furthermore, we have an sbt protocol that is respiratory therapist driven. our low compliance rates could highlight the difficulty of translating evidence-based practice to bedside, or they may represent a defect in our protocol design preventing meaningful change in the practice behavior and culture of our front-line staff. our data demonstrated that 1.8% of mechanically ventilated patients were mobilized into a chair, and only 60.1% were evaluated by a physical therapist while receiving mv. early and progressive mobilization has been demonstrated to be both safe and feasible for patients admitted to critical care. 25 implementing early mobility programs has led to improvements in physical function and mobility levels, significant reductions in both icu and hospital los, and ventilation days and a reduction in both the incidence and duration of delirium. 26 in fact, the abcde bundle is centered on approaches to implement the integrated pain, agitation, and delirium clinical practice guidelines to reduce delirium and weakness related to oversedation, prolonged mechanical ventilation, and immobility in mechanically ventilated critically ill patients. 27 despite this, point prevalence surveys have shown that rehabilitation levels remain low. goddard and colleagues, 28 using a theoretical domains framework of behavior change, found that the social influences domain (local champions, icu leadership, discord between team members and family members) and behavioral regulation domain (feedback and having a unit protocol) may act as barriers or facilitators to early rehabilitation. based on these findings, we formulated a multidisciplinary team and a mobility protocol to provide tools to standardize the care of our patients (appendix 1). the strengths of our study include the use of prospective collected data, a large sample size with all patients observed daily until icu discharge, and a common surveillance system using standardized definitions with a web-based portal for real-time reports. despite its strengths, our study has several potential limitations. first, a reduction in vae rates might be beyond the effect of just implementing the bundle, because the vae rates might have decreased secondary to other simultaneous infection control projects in our icus. second, this was not a preintervention and postintervention study, so analyzing the full effect of the bundle is difficult. third, despite having standardized data collection techniques and sources, team members might be motivated to demonstrate improvement and potentially could bias results. fourth, we report vae rates per 1,000 ventilator days, and any intervention that decreases ventilator days may paradoxically increase vae rates and underestimate the impact of the intervention on vae outcomes. fifth, icu los may depend on multiple complex factors and not only vaes. finally, the data represent a cohort study from a single center, and our inventions might not be generalized to other institutions. sustaining a safety culture should be a public health priority of all health care facilities. a strategic framework for preventing vaes is to pair clinical bundle with practice behavior and culture change interventions. the implementation of a multipronged program like the cusp 4mvp-vap that places ownership on front-line staff, reduces appendix a early mobility protocol complexity, provides standardized tools, engages executives, and uses communication tools to strengthen teamwork could improve the care processes and outcomes of mechanically ventilated patients. the impact of a ventilator bundle on preventing ventilator-associated pneumonia: a multicenter study guidelines for severe infections: are they useful? liberation and animation for ventilated icu patients: the abcde bundle for the back-end of critical care the preventability of ventilator-associated events. the cdc prevention epicenters wake up and breathe collaborative search for direct top squark pair production in final states with one isolated lepton, jets, and missing transverse momentum complications of mechanical ventilation-the cdc's new surveillance paradigm observation of a new chi(b) state in radiative transitions to upsilon(1s) and upsilon(2s) at atlas creating high reliability in health care organizations targeted implementation of the comprehensive unit-based safety program through an assessment of safety culture to minimize central line-associated bloodstream infections introducing the comprehensive unit-based safety program for mechanically ventilated patients in saudi arabian intensive care units comprehensive unit-based safety program (cusp) to improve patient experience: how a hospital enhanced care transitions and discharge processes the impact of implementing multifaceted interventions on the prevention of ventilator-associated pneumonia ventilator-associated events 5 years later ventilator-associated events and their prevention descriptive epidemiology and attributable morbidity of ventilator-associated events the clinical impact of ventilatorassociated events: a prospective multi-center surveillance study the impact of ventilator-associated events in critically ill subjects with prolonged mechanical ventilation should ventilator-associated events become a quality indicator for icus? potential strategies to prevent ventilator-associated events improving hospital survival and reducing brain dysfunction at seven california community hospitals: implementing pad guidelines via the abcdef bundle in 6,064 patients surviving sepsis campaign: international guidelines for management of sepsis and septic shock strategies to prevent ventilator-associated pneumonia in acute care hospitals: 2014 update two-state collaborative study of a multifaceted intervention to decrease ventilator-associated events safety of patient mobilization and rehabilitation in the intensive care unit. systematic review with meta-analysis earlier and enhanced rehabilitation of mechanically ventilated patients in critical care: a feasibility randomised controlled trial a feasibility study of a randomised controlled trial to examine the impact of the abcde bundle on quality of life in icu survivors barriers and facilitators to early rehabilitation in mechanically ventilated patients-a theory-driven interview study we thank dr. sean m. berenholtz (professor, johns hopkins armstrong institute for patient safety and quality) and the johns hopkins armstrong institute for patient safety and qualityàcusp 4mvp vap team. key: cord-332243-6uc4ricy authors: lai, joanna y.f.; guo, y.p.; or, peggy p.l.; li, yi title: comparison of hand contamination rates and environmental contamination levels between two different glove removal methods and distances date: 2010-09-25 journal: am j infect control doi: 10.1016/j.ajic.2010.06.007 sha: doc_id: 332243 cord_uid: 6uc4ricy background: gloves are a necessary contact precaution to prevent transmission of infectious pathogens that spread by direct or indirect contact with an infected person or a contaminated environment. this article reports a study investigating hand and environmental contamination levels when health care workers (hcws) followed two different methods of removing gloves at two distances from the rubbish bin. methods: fifty hcws performed a personal or causal glove removal method (pretest) and a centers for disease control (cdc)-recommended glove removal method (posttest) at distances of 2 feet and 3 feet from the rubbish bin after the application of fluorescent solution (the simulated contaminant) onto their gloved hands. results: the incidence of the small patch of fluorescent stain (<1 cm(2)) on the front of the doffed gloves was significantly lower in the posttest than in the pretest. the incidence of small and large patches (>1 cm(2)) on the front of the doffed gloves and on the cover of the rubbish bin was significantly lower at 3 feet than at 2 feet. health care assistants had significantly higher levels of contamination than other hcws in the pretest but not in the posttest. there was no significant difference in hand contamination rate between pretest and posttest based on distance from the rubbish bin and type of hcw. conclusion: the impact of the glove removal procedure and the distance to the bin in which used gloves are discarded should be taken into consideration on a daily basis, along with the supervision of infection control measures by minor staff. the consequences of bioterrorism and the threat of emerging infectious diseases, such as smallpox, severe acute respiratory syndrome (sars), and a recent new type of influenza a (h1n1), have become a reality for frontline health care workers (hcws). [1] [2] [3] [4] [5] [6] the use of personal protective equipment (ppe) is recommended for optimal protection from cross-infection among patients and other hcws. [3] [4] [5] [6] [7] gloves are not only necessary for contact precautions, but also essential for preventing the transmission of infectious bacteria, viruses, and microorganisms that can spread by direct or indirect contact with an infected person or contaminated environment. [7] [8] [9] gloves also reduce the transmission risks posed by the presence of excessive wound drainage, fecal incontinence, or other bodily discharges. 10 despite the recommendations, the risk of health care-associated infection through transmission of microorganisms from contaminated gloves to hcws' hands remains, however. [11] [12] [13] pittet et al 14 and boyce 15 reported finding bacteria from patients on the hands of 30% of hcws who had worn gloves for each patient contact. pittet et al 14 found that hcws who wore gloves during patient contact experienced hand contamination at an average rate of 3 colony-forming units (cfu) per minute of patient care. bacteria and viruses can be passed to hcws' hands through gloves or by contamination of hands during glove removal. 12, [16] [17] [18] [19] the possibility of contamination considerably increases the potential risk to hcw's hands, which can become infected by contact with a glove at the time of removal. in addition, because latex gloves are elastic and stretchable, certain areas of a working environment might be contaminated by the stretching motion during glove removal. 20 thus, unpredictable contamination could stain the clinical environment. most previous studies have identified hand contamination 9, 21 and the permeable effect of gloves 22,23 as problematic; however, few studies have explored the possible environmental contamination caused by the stretching motion during glove removal. recent studies noted that some hcws became infected with sars despite wearing full ppe (gloves, gown, and n95 respirator). 2, 24, 25 this ''through precautions'' transmission might be caused by contamination during the removal of protective clothing. 26, 27 a study examining self-contamination rates in hcws wearing two personal protective systems found that the anterior neck, forearms, wrists, and hands were the likeliest zones for contamination during removal of protective systems. 28 this points to the importance of properly removing ppe, including gloves, which may minimize self-contamination, contamination of the working environment, and possibly contamination of patients. the centers for disease control and prevention (cdc) has recommended a ppe doffing method for removing gloves since the sars attack in 2003. 29 to minimize contamination during the removal of contaminated gloves, the focus must be on the doffing method used. however, to date no studies have examined the effects of the cdc-recommended method on the preventing contamination by comparing the contamination rates associated with the cdc's glove removal method and personal or causal glove removal methods (ie, those predominately used in daily practice). given the vital need to prevent contamination from gloves, this study had 2 purposes. the study set out to examine the hand contamination rates and environmental contamination levels when (1) different methods of glove removal were followed, including personal or causal methods (pretest) and the cdc's recommended method (posttest), and (2) the distance to the bin varied between 2 feet and 3 feet (customary distances used by hcws in hong kong), measured in the common gown down areas (ie, designated areas for hcws to gown down their ppe) in the fever and cohort wards (wards for patients with epidemiological and clinical information suggestive of a similar diagnosis to share rooms, and with a spatial separation of at least 1 meter from one another) of a public hospital in hong kong. in the posttest, all of the subjects had to follow the cdc's glove removal steps. for the pretest, subjects could remove gloves however they wished, which differed considerably from the cdc method. we hypothesized that (1) different methods of glove removal have different effects on hand contamination rates and environmental contamination levels; (2) contamination levels differ between the 2 foot and 3 foot distances from the rubbish bin; and (3) following the cdc's glove removal method may significantly decrease contamination of hcws and the environment. a total of 50 subjects were invited to participate in this study, including 42 females (nurses and health care assistants) and 8 males (nurses). all participants were recruited from a 1,800-bed acute care hospital in hong kong, but although we used a convenience sampling method and attempted free sequencing, the sequence was not by randomization. reflecting the female predominance in the nursing profession, 84% of the subjects were female and 16% were male. the study included 10 temporary undergraduate nursing students (tunss) who had more than 2 years prework experience (ie, a job working in the hospital before promotion to nursing staff) in different departments, including 4-month rotations in surgical, medical, pediatric, orthopedic, neurosurgical, and accident and emergency departments. in addition to the tuns, the sample included 4 health care assistants (hcas), 30 registered nurses (rns) or enrolled nurses (ens), and 6 nursing officers (nos), including advanced practice nurses (apns). because each subject completed the experiment on the same day, the response rate was 100% in this study. two subjects performed the same glove removal method in the pretest and posttest and were replaced by two subjects who followed the specified processes. the total sample size was 50. the subjects' demographic data are summarized in table 1 . ethics approval was applied for before the study began, and the experimental protocol was approved by the human subjects ethics subcommittee of the hong kong polytechnic university before the start of the experiment. each subject provided written informed consent before taking part in the study and after being familiarized with the study's nature, purpose, method, and risks. all subjects were volunteers and could withdraw at any time without any reason. confidentiality and anonymity were ensured. the study was completed on the same day, with no subjects returning for follow-up, and no dropouts were noted. disposable latex gloves were used for the test, because latex is the material generally used by hong kong hospital authority (hkha). powder-free latex gloves (saf-care plus; careplus (m) sdn bhd, seremban, negeri sembilan, malaysia) were purchased from the hkha's supplier. powder-free latex gloves carry less risk of leakage compared with vinyl gloves. 22, 23 each subject selected the glove size (small, medium, or large) that he or she uses daily and examined the integrity of the glove by manual checking. after the glove integrity was double-checked by the researcher, the fluorescent solution was applied. no leakage or reuse of gloves was allowed, because this might have affected the contaminated fluorescent patch (fp). yellow fluorescent organic dye is used in angiography for the diagnosis and categorization of vascular disorders. 30 many studies use fluorescent stain to represent the contamination caused by pathogens. 28, [31] [32] [33] following zamora et al, 28 a contamination stain larger than 1 cm 2 was considered a large patch, and one smaller than 1 cm 2 was considered a small patch. figure 1 shows some fps detected on the edge of the rubbish bin cover and on the cover itself. the fluorescent solution was diluted from 20 g of free acid fluorescent dye (f2456 free acid dye; sigma-aldrich chemil gmbh, munich, germany) into a 1 m sodium hydroxide solution (fixamal; sigma-aldrich chemil gmbh) to form a water-soluble solution of fluorescent sodium. once the product was completely dissolved, 2 l of water was added to form a suspension. for the study, 5 ml of the fluorescent solution was sprayed on each gloved palm (a total of 10 ml on both palms) (fig 2) . as mentioned earlier, fluorescent dye is not known to be harmful to the human body and can be injected into veins in a fundus fluorescein angiogram to safely and effectively diagnose eye problems. 31 in the present study, the final fluorescent solution applied to on each gloved palm was similar to that used in fundus fluorescein angiography (0.05 g/5 ml). 31 the subjects were instructed to repeat the following procedure 5 times: pull back a plunger to fill a bladder wash syringe with 60 ml of air and then expel all 60 ml of air. this procedure was considered a common simulation of a simple daily nursing procedure, such as a ryle tube feeding or bladder washout. this simple procedure was completed before doffing gloves. three large pieces of white cloth were placed onto the wall in front of and on both sides (left and right) of the subject. the white cloth was intended to clearly show the fps. due to the difficulty in counting the small patches, the researcher drew a grid (30 cm 2 squares) on all white cloths to facilitate the counting in each individual grid. the ultraviolet (uv) lamp (stylish 12'' fluorescent lantern; john manufacture ltd; hong kong, china) is useful for detecting fps, making the invisible stained patch visible. the uv lamp was checked and tested before the study; the same brand of uv lamp was used throughout the study period, to prevent any significant mismatch in the results. all participants assessed the uv lamp before donning the gloves and protective clothing to ensure that no fluorescent solution was present. the researcher recorded the time taken for glove removal in the pretest and posttest periods. in brief, in an experimental laboratory (ambient temperature, 22;258c; relative humidity, 70%), each of the 50 subjects completed the pretest and posttest glove removal at two separate sessions separated by a 30-minute interval after 10 ml of the fluorescent solution was sprayed on both palms. a video demonstrating the cdc's recommended glove removal method was shown between two sessions. after glove removal, fps were counted by a uv scan under dim light. skin testing for allergy to fluorescent dye was performed before the testing to exclude any subject with an allergy and avoid the risk of an allergic reaction. figure 3 shows the procedural sequence. all data were analyzed using spss 17.0 for windows (spss inc, chicago, il). descriptive statistics were used for all independent variables, including subjects' sex, age, rank, and work experience. a repeat measurement was made to compare the results of the cdc glove doffing method at two different distances (2 feet and 3 feet) between the subject and the rubbish bin. hotelling's t 2 test of multivariate analysis was used to identify any significant differences in contamination of the front white cloth between the pretest and the posttest. one-way analysis of variance was applied to the data to compare the sample means of ranking of staff and the time of glove removal. when a significant difference for a main effect was obtained, the multiple-comparisons method of bonferroni was used to identify specific differences. all reported differences were considered significant at p , .05. pretest and posttest figure 4a shows the small patches of fluorescent stain on the front of the cloth for the pretest and posttest. there were significantly fewer small patches in the posttest than in the pretest (p , .05), suggesting that the cdc glove removal procedure reduced the number of small patches. no significant differences were noted in other contamination stains of different sizes and at different sites. table 2 shows the level of contamination at 2 feet and 3 feet from the rubbish bin. there were significantly fewer small patches on the front of the cloth and on the cover of the rubbish bin at 3 feet than at 2 feet (f 5 12.8, p , .001 and f 5 19.6, p , .001, respectively), averaging 11.8 and 7.8, respectively, for the pretest and 3 and 2.9 for the posttest. similarly, there were significantly fewer large patches on the front of the cloth and the cover of rubbish bin at 3 feet than at 2 feet (f 5 11.3, p 5 .001 and f 5 3.9, p , .05, respectively), averaging 0.2 and 0.1 for the pretest, and 0.16 and 0.2 for the posttest. as shown in table 2 , the small patches were more common than the large patches. figure 4b shows hcw rankings for the small patches on the front of the gown at pretest and posttest. significant differences among hcw rankings can be seen in the pretest (f 5 4.08, p 5 .01). hcas had significantly higher levels of contamination compared with rns, ens, and tunss. however, there was a significant improvement in the rate of contamination after the cdc glove removal demonstration, with no significant differences among different types of staff seen in the posttest. on an average, subjects removing gloves following the cdc glove removal method required 10.9 seconds (range, 6-23 seconds), whereas those removing gloves following a personal or causal doffing required only 6.1 seconds (range, 2-12 seconds; f 5 145.3; p , .001) (fig 5) . there were no significant differences in hand contamination rate between the two groups in terms of pretest and posttest, distance, and hcw ranking. this study shows that glove removal induces contamination of the environment. at 2 feet from the rubbish bin, we detected small patches of fluorescent stain after the two glove removal methods, an average of 15.9 and 10.3 patches for the pretest and 9.2 and 6.7 for the posttest. at 3 feet, the number of these patches was reduced significantly, from 11.8 and 7.8 for the pretest to 3 and 2.9 for the posttest. significantly fewer large patches were found, averaging 0.1-0.2 patch at 2 feet and virtually 0 at 3 feet. these findings might imply the following potential mechanisms for transmission of diseases spread by glove removal: (1) glove removal mainly induces environmental contamination, especially on the front of removed gloves and the cover of rubbish bin, rather than hand contamination. (2) contamination levels differ between the 2-foot and 3-foot distances from the rubbish bins (the former is higher). the environmental contamination would be greatly reduced by increasing the distance by about 1 foot when discarding used gloves. and (3) small patches are the more frequent form of contamination. our findings support the validity of our first two hypotheses proposed earlier in the article. our results also verify the third hypothesis as well. there were significantly fewer small patch of fluorescent stain on the front of the cloth and on hca's gowns after the cdc glove removal demonstration. these observations show that the cdc glove removal method significantly decreased the rate of contamination of the environment and hcws, indicating that the cdc recommendations can help eliminate contamination of the area between the hcw and the environment. these findings need to be shared with hcws to emphasize the importance of evidence-based practice to their daily practice. most hcws have learned the cdc glove removal steps after the sars outbreak of 2003, and many attend infection control lectures periodically to refresh their practice. nonetheless, some of the subjects had forgotten the cdc glove removal steps before watching the video for this study. our hospital has many posters reminding frontline hcws about hand hygiene and the sequence for removing ppe, yet none of these hcws followed the cdc glove removal procedure. as far as the results of this study are concerned, the cdc glove removal procedure is certainly essential to prevent cross-infection in daily practice. thus, we recommend posting related information and continue reminding hcws about infection control measures through lectures, talks, pamphlets, posters, and supervisory interactions. previous studies have focused mainly on either hand contamination 34, 35 or contamination of other ppe components. 8, 9, 12, 14, 28, [31] [32] [33] limited research has explored environmental contamination due to the stretching action of removing gloves. our data fill this research gap and suggest many helpful implications for infection prevention and control. our findings suggest that hcws should avoid standing in front of a patient, other hcws, or clean areas such as the nursing station while removing gloves. such measures may be included in the usual infection control measures that facilitate the prevention of cross-infection and environmental contamination. likewise, the placement of the rubbish bin is also an important point, given that most hcws remove their gloves in front of the bin. we recommend not placing the rubbish bin under the sink used for hand hygiene. standing in front of the sink while removing gloves could result in contamination of the edge of the sink. contamination and recontamination on the front side of their working clothes also might occur when hcws approach the sink for hand hygiene afterward. thus, we recommend that the rubbish bin be placed at least 2 feet away from the sink. in this study, hcas had a significantly higher level of contamination compared with rns, ens, and tunss in the pretest period. hcas might lack systemic knowledge of nursing science, especially in the area of infection control because they were only trained for 1 month in such basic nursing procedures as measuring urine output, emptying urine bags, providing tube feedings, and changing napkins before they were employed. their use of a personal or causal glove removal procedure in their daily practice might have led to higher rate of environmental contamination. this findings indicates that minor staff should pay more attention to infection control as an essential part of their daily practice, and that closer supervision should be provided. the hcas did demonstrate decreased environmental contamination after viewing the cdc glove removal video and demonstration; therefore, there were no differences in ranking in the posttest period. this finding supports the importance of training and supervision for minor staff on proper glove removal. although the cdc method offers superior protection against environmental contamination, it takes longer, likely due to rusty technique. it is conceivable that more trainings and practice exercises will decrease the time required for glove removal. in summary, more contamination was spread in the area between the hcw and the environment as well as on the cover of the rubbish bin when gloves were removed following a personal or causal method, and following the cdc glove removal procedure significantly decreased contamination of the environment and hcws. our findings underscore the importance of following the appropriate procedure for removing gloves and maintaining the proper distance between the hcw and the rubbish bin when discarding used gloves, as well as the need for proper training and supervision of minor staff in infection control measures. of course, caution is recommended when interpreting these data, given the limitations of this study. the unequal ratio of male and female subjects due to the female dominance of the nursing profession made it difficult to compare results, even though no sex-based differences were evident. the random sampling for future studies should recruit hcws from a larger target population, such as different hospitals or clinics in hong kong. despite these limitations, this study provides a valuable first step in examining how contaminants spread during glove removal and underscore the importance of following the cdc's glove removal procedure. future studies should focus on examining the full ppe system and systematically recording the need for informed recommendations from the cdc regarding the removal of the full ppe system. the project was supported and supervised by an infection control dissertation project of hong kong polytechnic university. the authors thank k. f. leung for his helpful suggestions regarding statistical analysis, as well as their 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apparel doffing. us patent 7246382 changes in the epidemiology of methicillin-resistant staphylococcus aureus in intensive care units in us hospitals examination gloves as barriers to hand contamination in clinical practice leakage of virus through used vinyl and latex examination gloves severe acute respiratory syndrome from the trenches, at a singapore university hospital possible sars coronavirus transmission during cardiopulmonary resuscitation transmission and control of sars sars and the removal of personal protective equipment contamination: a comparison of 2 personal protective systems donning personal protective equipment nurse practitioner's drug handbook. springhouse (pa): springhouse corp in vivo protective performance of n95 respirator and surgical facemask transmission of communicable respiratory infections and facemasks effective personal protective clothing (ppc) for healthcare workers attending patients with severe acute respiratory syndrome (sars) removal of nosocomial pathogens from the contaminated glove: implications for glove reuse and hand washing barrier protection with examination gloves: double versus single key: cord-303685-sxsrz60h authors: guthery, eugene; seal, lawton a.; anderson, edward l. title: zinc pyrithione in alcohol-based products for skin antisepsis: persistence of antimicrobial effects date: 2005-01-29 journal: am j infect control doi: 10.1016/j.ajic.2004.07.012 sha: doc_id: 303685 cord_uid: sxsrz60h alcohol-based products for skin antisepsis have a long history of safety and efficacy in the united states and abroad. however, alcohol alone lacks the required antimicrobial persistence to provide for the sustained periods of skin antisepsis desired in the clinical environment. therefore, alcohol-based products must have a preservative agent such as iodine/iodophor compounds, chlorhexidine gluconate, or zinc pyrithione, to extend its antimicrobial effects. iodine, iodophors, and chlorhexidine gluconate are well-characterized antimicrobials and preservatives. the thrust of our effort was to examine the characteristics of the lesser-known zinc pyrithione and to evaluate its utility as a preservative in the formulation of alcohol-based products for skin antisepsis. this work includes a literature review of current zinc pyrithione applications in drugs and cosmetics, a safety and toxicity evaluation, consideration of the proposed mechanisms of antimicrobial action, in vitro and in vivo efficacy data, and a discussion of the mechanisms that confer the desired antimicrobial persistence. in addition, alcohol-based, zinc pyrithione-preserved, commercially available products of skin antisepsis are compared with other commercially available antimicrobials used for skin antisepsis and with additional alcohol-based products with different preservatives. the authors' conclusion is that zinc pyrithione is not only a safe and effective antimicrobial but that its use in certain alcohol-based formulations results in antimicrobial efficacy exceeding that of iodine and chlorhexidine gluconate. alcohol-based products for skin antisepsis have enjoyed a long history of safety and efficacy in the united states, as well as in many countries abroad. examples of use include surgical scrubs, health care personnel handwashes, patient preoperative skin preparations, injection/catheter site preparations, preoperative antiseptic shower solutions, hand rubs/ sanitizers, and tinctures such as those of iodine. [1] [2] [3] [4] [5] of the antimicrobials routinely used for skin antisepsis (alcohols, chlorhexidine gluconate [chg] , iodine/iodophors, parachlorometaxylenol [pcmx] , triclosan, and quaternary ammonium compounds), alcohols are by far the fastest acting and most efficacious. [6] [7] [8] [9] [10] [11] almost exclusively, the short-chain, aliphatic alcohols-ethanol, isopropanol, and, in europe, n-propanol-are used for skin and hand antisepsis. they have excellent activity against bacteria, fungi, and enveloped (and some nonenveloped) viruses. 10 alcohols may be used either alone or in combination with other antimicrobials to increase the efficacy and confer substantivity (persistence). the centers for disease control (cdc) and prevention in its ''guideline for prevention of surgical site infection, 1999'' acknowledged the utility of alcoholbased products in preoperative hand/forearm antisepsis and preoperative skin preparation. 12 in late 2002, the recommendations of the healthcare infection control practices advisory committee and the hic-pac/shea/apic/idsa hand hygiene task force were published. 9 this report recognized the speed and broad antimicrobial spectrum of alcohol, codified uses for alcohol-based products in skin antisepsis practices, and noted the lack of antimicrobial persistence associated with alcohol when used alone. the fda also noted alcohol's lack of antimicrobial persistence; however, it allows a preservative agent to be incorporated into the vehicle (defined as the product without the active ingredient) to provide for the persistent antimicrobial effect necessary to sustain a reduction in the number of bacteria for 6 hours postapplication. 4 the preservative supplies the required persistent antimicrobial activity for these formulations to meet or exceed the established agency efficacy. preservative systems in some of the currently marketed alcohol-based products for skin antisepsis include iodine/iodophors compounds, chg, and zinc pyrithione (zpt). although much has been written about the antimicrobial effects and the preservative potential of iodine and chg, little has been published regarding these characteristics as attributes of zpt. therefore, this article includes a brief review of the published literature related to the development, safety, efficacy, and clinical utility of zpt and evaluating its merits as a preservative for alcohol-based products of skin antisepsis. synthesis, structure, and solubility the natural antibiotic aspergillic acid contains a cyclic hydroxamic acid functional group in a pyrazine nucleus. attempts to develop synthetic methods for introducing heterocyclic rings into the hydroxamic acid group present in aspergillic acid led in 1950 to the preparation for n-hydroxy-2-pyridinethione (hpt). the synthesis was achieved by conversion of a 2pyridyl ether to its n-oxide, followed by dealkylation. 13 reaction of 2-bromopyridine-n-oxide with thiourea forms 2-pyridyl-n-oxide-isothiourea hydrobromide and, followed by treatment with aqueous sodium carbonate, produces n-hydroxy-2-pyridinethione (hpt). 14 this compound was shown to have potent antimicrobial properties. in vitro, 1 mg hpt would inhibit staphylococcus aureus. 15 thus, this synthetic analog was 30 times more potent as an antimicrobial than the native aspergillic acid. later, hpt was shown to have extremely potent activity against gram-positive and gram-negative bacterial species as well as strong activity against yeasts and fungi: eg, aspergillus, trichophyton species, candida albicans, and cryptococcus species. 16 cox, in the mid-1950s, reviewed the uses of pyridine-n-oxides and noted that the mercapto derivatives formed quaternary ammonium compounds or heavy metal salts, which were described as effective fungicides and antibacterial agents and suggested their uses in pharmaceutic preparations. 17 as a zinc chelate of hpt, zptexists in the monomeric form as 2 pyridine rings bound to a central zinc atom by bonds between the zinc atom and the sulphur and oxygen molecules of the pyridine ring structures. 18, 19 zpt is practically insoluble in water, organic solvents, or surfactants-a property that can be problematical when formulating with the compound. 20 the structure of zpt is presented in fig 1. applications zpt has a long history of numerous medical, scientific, and industrial applications. the compound has a master file registered with the fda. of some 1350 compounds screened, zpt was one of the most active antifungal and antibacterial compounds examined. 20, 21 for example, pityrosporum ovale is thought to play a pathogenic role in skin conditions such as seborrheic dermatitis and dandruff. 22 this led one well-known pharmaceutic company to conduct safety evaluations of zpt in a shampoo formulation. 21 the result was an antidandruff product, head & shoulders (procter & gamble, cincinnati, ohio) that is currently sold over-the-counter with 1.0% zpt as the active ingredient. presently, the fda acknowledges the efficacy of zpt in the treatment of dandruff and seborrheic dermatitis. 23, 24 the zpt-based shampoo has shown to be effective in treating tinea versicolor, 25 and it is highly effective for psoriasis of the scalp. 26 cosmetic preservation has been a frequent use of zpt for many years. 18 zpt has proven to be effective, even at low concentrations, against both gram-positive and gram-negative bacteria and fungi. it is compatible with most commonly used cosmetic ingredients; has a good toxicity profile for this type of application; and can be safely used to minimize discoloration, off-odors, and emulsion breaks because of microorganisms. zpt helps to prevent spoilage of cosmetics because of microbial contamination during use, is found in gojo hand cleaner products (gojo industries, inc. akron, ohio), and in over-the-counter antimicrobials such as lanacane (combe, inc.,white plains, ny). 27 finally, zpt has also been used in commercial laundries for inhibiting mold growth on fabrics. 20 in addition to a 50-year product history, the safety and toxicity of zpt has been formally evaluated in animal models and by in vitro and human in vivo studies. when zpt was applied to intact skin of monkeys with surfactants, the absorption was only 0.20% of the amount applied. 28 concentrations of zpt in the blood stream following topical application are below the threshold of detection. the absorbed dose would likely be further reduced in humans by the fact that hand skin has a lower permeability than scalp skin. 29,30 zpt does not induce primary skin irritation or sensitization in human skin. 30 finally, when a 2.0% suspension of zpt was instilled into the conjunctival sacs of the eyes of 6 albino rabbits, zpt produced only slight irritation of the conjunctival vessels, which lasted 3 days, but no corneal opacities were observed. 31 ocular toxicity is well known to be associated with other preservative systems such as chg, and skin irritation and sensitization with iodine and chg-based products has been documented. 10, [32] [33] [34] antimicrobial activity the available data on the mode of antimicrobial action suggest that zpt is membrane active, as indicated by the inhibition of uptake of several unrelated substrates in both bacteria and fungi [35] [36] [37] [38] and the observed depolarization of the transmembrane potential in neurospora crassa. 39 the effects of an antimicrobial agent on substrate transport and related metabolism may be used as indicators of the membrane activity of the test agent. 40 in turn, these effects may be reflected as a reduction in intracellular atp levels. 41 zpt is a poor inhibitor of substrate catabolism. subinhibitory concentrations of the biocide greatly reduce intracellular atp levels in both escherichia coli and pseudomonas aeruginosa. this is thought to be due to the action of zpt on the gram-negative bacterial membrane. 42 further investigation of the action at the membrane suggests that zpt forms stable interactions with the bacterial membrane phospholipid phosphatidylethanolamine. this may result in the disaggregation of the phospholipid head structure at the outer membrane and may also indicate chelation of phosphorylethanolamine head groups from the core structure of the external lipopolysaccharide. this would further disrupt the membrane. 43 in addition, currentvoltage analysis demonstrates that the depolarization of the bacterial membrane is accompanied by a decrease in membrane electrical conductance in a manner consistent with inhibition of the primary proton pump and consistent with a mode of action of zpt on plasma membrane ion channels. therefore, zpt inhibits membrane transport via a direct or indirect effect on the primary proton pump that energizes transport, and the site of action of zpt is likely to be intracellular rather than extracellular. 42 other studies on the mode of action of pyridine-n-oxides has demonstrated their potent bactericidal activity to be linked to their ability to chelate: ie, to form cyclic complexes with the ions of heavy metals. 44 additional investigations reported by hyde and nelson have suggested that other mechanisms may be applicable. 18 the authors propose that the pyrithione is an antimetabolite of the pyridine derivative pyridoxal and suggest that the activity of zpt may be analogous to the inhibition of microbial folate production by sulfa drugs. finally, dipole structure of the molecule creates a pseudoquaternary ammonium group, providing yet another potential mode of antimicrobial action for zpt. multiple mechanisms appear to be at work, suggesting that antimicrobial resistance is unlikely to develop. reports of the development of antimicrobial resistance are not readily available, and further detailed investigation may be appropriate. in vitro efficacy data. the in vitro composite data in table 1 document the broad spectrum of antimicrobial activity of zpt as well as quantify the inhibitory capacity of this compound when tested against numerous bacteria, yeast, and fungi (personal communications from ron jones, m. d., professor and director, division of medical microbiology, director, anti-infectives research center and special microbiology laboratories, department of pathology, university of iowa college of medicine, iowa city, ia, january 1993). 20, 22, 27, 42 the antimicrobial range of zpt is sufficient to include many pathogenic, opportunistic, and saprophytic organisms. inhibitory concentrations are often achieved at a level of 40 mg/ml (40 ppm) or less for numerous pathogenic species. in vivo efficacy and persistence data. in 1979, leyden et al 45 developed a novel in vivo assay now known as the persistence (substantivity) test. this significant development was used to demonstrate the in vivo efficacy of zpt in topical antisepsis applications. the assay determines the ability of the test agent to establish a reservoir in the stratum corneum. substantive agents that diffuse into the stratum corneum or bind chemically to it will not be readily removed either by loss from the surface or by absorption. the antibacterial effect will therefore last several days. for this assay, 0.5 ml of the test agent is applied with a pipette twice daily for 4 consecutive days to the entire volar forearm. twenty-four hours after the last application, occlusive dressings are applied. if an antimicrobial effect is demonstrable, the test is repeated, and the posttreatment interval is extended to 72 hours. the geometric means for bacterial counts per square centimeter are determined. for this study, 1.0% zpt was compared with an equal concentration of chg. the results of this 8-subject study demonstrated antimicrobial parity at 24 hours; however, at the 72-hour time point, zpt provided a greater persistent effect than the comparator (zpt = 120 vs chg = 87,000 colonies/cm 2 recovered). the suppression of the bacterial counts on the forearm 72 hours postapplication for zpt is significantly greater than for chlorhexidine gluconate. these data support the superior efficacy and the persistence of zpt for this indication. in addition, leyden et al 45 devised an ''expanded flora test'' to evaluate further the in vivo antimicrobial efficacy and persistence of topical antiseptics. this test measures the ability of an agent to suppress a dense and flourishing population of organisms. for this study, the forearm is wrapped with several layers of impermeable plastic film and then sealed at the wrist and below the elbow for 24 hours to expand the resident flora. after expansion of the resident flora, 2, 2.5 cm 2 areas on each arm are treated with 0.1 ml of the test agent administered by a plastic tuberculin syringe. all sites are immediately covered with a 5.0-cm 2 section of impermeable plastic film. encircling the limb with plastic tape as the final step occlusively seals the site. a strip of 1.25-cm (0.5 in.)-wide, white-backed adhesive tape is placed between each test site to prevent the possibility of translocation of test agents and organisms from 1 site to another. sites are cultured at 6, 24, and 48 hours, depending on the stability of the test agent. the geometric mean of surviving organisms is determined by standard culture techniques. for the lynden study reviewed here (table 2) , 70% ethanol and 1.0% zpt were compared in a 10-subject panel. as expected, ethanol induced a prompt, significant reduction in bacterial flora that was still measurable at the 6-hour sample when compared with the untreated control sample. the lack of an equally dramatic antibacterial effect 6 hours postapplication for zpt suggests that a quick-acting antiseptic, such as alcohol, should be combined with it. in this fashion, the alcohol (which lacks persistence) will produce an immediate bactericidal action, and the zpt (which lacks a dramatic quick kill) will produce a prolonged suppression of the skin bacterial flora. this concept is supported by the zpt data obtained at the 24-and 48-hour sample points. following topical application, zpt is deposited in the epidermis; however, the largest proportion of zpt is deposited on the outer layers of the stratum corneum. 27, 45 zpt is soluble in sebum, and, when applied to the skin, the zpt in sebum is localized in the hair follicles. no transepidermal penetration occurs. the articles provided do not suggest whether the ''dissolution'' is of the intact zpt or whether the zinc is first chelated by a separate mechanism, thus leaving the more soluble pyrithione available to penetrate via the follicle. others 46 used zpt with radioactive sulfur to monitor tissue location so that the pyrithione moiety would be observed. deposited particles of zpt appear to adhere firmly to the hair and stratum corneum and to withstand copious rinsing. 46 these adherent particles probably act as a reservoir and are responsible for the prolonged antimicrobial effect (persistence). diminution of the amount of antibacterial effect with time is probably due to a great extent to normal turnover of the stratum corneum. also, solubilized zpt would eventually purge and/or break down further. it is pertinent to note that sebum and topical lipids can inactivate many antimicrobials 47 ; examples include hexachlorophene and benzethonium chloride. zpt is not only soluble in sebum but retains its antimicrobial activity. given the significant history, safety, and diversity of zpt, it is only logical that other significant uses would be found for this antimicrobial. despite the limited solubility and the formulation challenges that are characteristic of the compound, zpt has been used successfully and most recently as a preservative system for several marketed alcohol-based products of skin antisepsis, at concentrations of 0.25% for waterless applications and up to 1.0% for water-aided products. these include surgical scrubs, health care personnel handwashes, patient preoperative skin preparations, and preoperative bath or shower solutions. 1 hobson et al was the first to document in vivo the value of zpt as a preservative system for an alcoholbased, water-aided surgical scrub formulation. the study compared the efficacy of 70% alcohol preserved with zpt to a second scrub containing only 4.0% chg and a third scrub containing only 7.5% iodine. their data were obtained following 11 scrubs over a 5-day period. 1, 4 the requirements for successful performance include log 10 reductions from baseline of not less than 1.0 for day 1, 2.0 for day 2, and 3.0 for day 5. the immediacy of kill provided by the alcohol-based product on day 1 was readily demonstrated by the nearly 3.0-log 10 reduction from baseline counts. the antimicrobial effect becomes enhanced on days 2 and 5 as a result of the contributions provided in part by the preservative system. at the end of the 5-day test period, the superiority of alcohol preserved with zpt was readily apparent (4.78-log 10 reduction from baseline) when compared with chg or iodine-based products (3.43-and 1.27-log 10 reduction from baseline, respectively) for the same day 5 time point. in a second in vivo study, a different formulation of an alcoholbased, zpt-preserved, waterless surgical scrub was compared with another waterless, alcohol-based scrub containing 1.0% chg as a preservative (avagard, 3m health care, st paul, minn). as may be observed in fig 2, the products performed similarly on days 1 and 2 (alcohol/zpt log 10 reductions from baseline = 2.32 and 3.07, respectively; alcohol/chg log 10 reductions from baseline = 2.08 and 2.87, respectively). however, by day 5, the antimicrobial efficacy of the alcohol/ zpt product was notably better (log 10 reduction from baseline = 3.68) than that of the alcohol/chg product (log 10 reduction from baseline = 3.09) because the zpt-preserved formulation more readily exceeded the 3.0-log 10 reduction required for the surgical scrub indication. 4 in a separate in vivo study, the cosmetic and skin-conditioning properties of the 2 waterless formulations were judged to be equal (personal communication, dr. ronald rizer; manuscript submitted for publication to aorn journal). additional testing was performed with the waterless alcohol/zpt formulation to assess its virucidal capacity against some common human pathogens. these included human coronavirus (hcov, atcc vr-740, both hcov and sars-hcov belong to the virus family coronaviridae), the human immunodeficiency virus type 1 (hiv-1, from zepto metrix corp. of buffalo, ny), hepatitis a virus (hav, from crem, university of ottawa), herpes simplex type 1 (hsv-1, atcc vr-260), and human rotavirus (strain wa, atcc vr-2018). these agents represent both rna and dna viruses, some with envelopes and others without. the hav and the human rotavirus represent 2 nonenveloped rna agents (one linear single-stranded, the other segmented double stranded) that are relatively resistant to known antimicrobials. using standard virologic techniques, the viral agents were cultured in cell lines appropriate for propagation (see table 3 ) to levels at or above the required titer of 10 6.00 infectious units/ml. the viruses were then harvested and exposed for 3 minutes ( 50 the results of this effort are summarized in table 3 . the test criterion for classification as a virucide is not less than a 3.0-log 10 reduction in the postexposure virus population, beyond any observed cytotoxicity. exposure to the product produced a 3-to 4-log 10 reduction in all virus populations tested, thereby meeting or exceeding the standard for classification as a virucide. seal and paul-cheadle confirmed in vivo the antimicrobial efficacy and thus the value of alcohol products formulated with zpt for added persistence. 5 their report demonstrated the superiority of an alcoholbased, zpt-preserved, preoperative shower solution used in combination with a similarly formulated patient preoperative skin preparation. the combination of an alcohol-based, zpt-preserved, preoperative shower solution and a similarly formulated patient preoperative skin preparation was compared with an iodine-based system (7.5% scrub and 10.0% pvpi paint) using identical application schedules in a well-controlled, human in vivo study. for this study, the subjects refrained from the use of any antimicrobial products for 2 weeks to allow for stabilization of the normal skin flora. pretreatment cultures were obtained of the selected sites (groin) to obtain ''baseline'' of skin flora, to which posttreatment data could be compared and log 10 reduction values calculated. the subjects then washed with the preoperative shower products at t = 212 and t = 26 hours. the preoperative surgical site preparations were applied at t = 0, and samples were collected at 10 minutes and from 6 hours out to 72 hours postapplication of the surgical site preparation. the alcohol-based products demonstrated superior efficacy at nearly every time point. at 72 hours (3 days) following the last product application, the alcoholbased, zpt-preserved system continued to provide significant antimicrobial action as documented by a 2.0-log 10 or a 99.0% reduction in the colony-forming units present at baseline. this compares with a ,0.50log 10 reduction for the same time point with the iodinebased products. the extended period of antimicrobial persistence that is associated with the zpt-preserved, alcohol-based system would allow for skin closure in a prolonged state of antisepsis and could result in a lower incidence of surgical site infections. alcohol provides fast-acting, broad-spectrum antimicrobial activity. however, the requirement for persistence in topical antiseptics cannot be achieved with alcohol alone. chlorhexidine gluconate, quaternary ammonium compounds, iodine, and triclosan have persistence features and have been added to alcohol solutions for antisepsis in europe and/or the united states for many years. antimicrobial persistence has been reported with chlorhexidine gluconate and triclosan, but it is slow to develop and is not always profound. 32, 34, 46 as a preservative (persistence agent) for topical antisepsis, zpt was found to have a safety profile and/ or antimicrobial efficacy that exceeds iodine, chlorhexidine gluconate, and triclosan. 1, 5, 32, 46, 49, 50 for these reasons, the antimicrobial persistence associated with zpt has recently been incorporated successfully into commercially acceptable, fda-compliant, patented products for surgical hand antisepsis and preoperative antiseptics. in conclusion, zpt is a safe and effective antimicrobial suitable for use as a preservative system with alcohol formulations. the data confirm that zpt contributes positively toward the overall antimicrobial efficacy of alcohol-based products in which it is used. additional studies would prove useful in verifying the clinical relevance of this observation. finally, it is likely that additional uses for this antimicrobial will be found as we continue the struggle with ever increasing resistance to current antibiotics and antimicrobials. development and evaluation of a new alcohol-based surgical hand scrub formulation with persistent antimicrobial characteristics and brushless application handbook of topical antimicrobials: industrial applications in consumer products and pharmaceuticals brushless surgical scrubbing and handwashing food and drug administration. 21 cfr parts 333 and 369. tentative final monograph for health-care antiseptic drug products: proposed rule. federal regulation part iii a systems approach to preoperative surgical patient skin preparation surgical scrub and skin disinfection apic guidelines for infection control practice: guideline for use of topical antimicrobial agents alcohols for antisepsis of hands and skin guideline for hand hygiene in the health care setting antiseptics and disinfectants: activity, action, and resistance handbook of topical antimicrobials: industrial applications in consumer products and pharmaceuticals guideline for the prevention of surgical site infection analogs of aspergillic acid. ii. various antibacterial heterocyclic hydroxamic acids analogs of aspergillic acid. iv. substituted 2-bromopyridine-n-oxides and their conversion to cyclic thiohydroxamic acids united states patent 2,734 in vitro studies with 1-hydroxy-2 (1h) pyridinethione pyridine n-oxides and their uses. manufacturing chemist sodium and zinc omadine as cosmetic preservatives structural characterization of bis (n-oxopyridine-2-thionato) zinc (ii) olin chemicals product data: zinc omadine and sodium omadine antimicrobial agents safety evaluation of zinc 2-pyridinethiol 1-oxide in a shampoo formulation the in vitro antifungal activity of ketoconazole, zinc pyrithione, and selenium sulfide against pityrosporum and their efficacy as a shampoo in the treatment of experimental pityrosporosis in guinea pigs food and drug administration. 21 cfr parts 348 and 358. dandruff, seborrheic dermatitis, and psoriasis drug products for over-thecounter human use: tentative final monograph anti-seborrhoeic qualities of zinc pyrithione in a cream vehicle an open trial of the effect of a zinc pyrithione shampoo in tinea versicolor the highly effective use of topical zinc pyrithione in the treatment of psoriasis olin chemicals product data: omadine antimicrobials for cosmetic preservation: combine broad spectrum antimicrobial activity and wide compatibility with cosmetic ingredients percutaneous absorption of zinc pyridinethione in monkeys deposition on the skin of particles of antimicrobial agents from detergent bases percutaneous penetration of dipyrithione in man: effect of skin color (race) toxicity of pyrithiones topical antimicrobial testing and evaluation. new york: marcel dekker handbook of topical antimicrobials: industrial applications in consumer products and pharmaceuticals safety and efficacy of the antiseptic chlorhexidine gluconate mechanism of the antibacterial action of pyrithione: effects on membrane transport, atp levels and protein synthesis studies on the mode of antimicrobial action of metal complexing thiohydroxamic acids against escherichia coli the influence of pyrithione on the growth of microorganisms growth and survival of klebsiella pneumoniae in the presence of pyrithione mechanism of pyrithione-induced membrane depolarization in neurospora crassa interaction of biocides with model membranes and isolated membrane fragments denyer sp, hugo wb, editors. mechanism of action of chemical biocides conservation and transformation of energy by bacterial membranes pyrithione biocides as inhibitors of bacterial atp synthesis pyrithione biocide interactions with bacterial phospholipid head groups the influence of chemical constitution on anti-bacterial activity. part viii. 2-mercaptopyridine-n-oxide, and some general observations on metal binding agents updated in vivo methods for evaluating topical antimicrobial agents on human skin the use of autoradiography to study the localization of germicides in skin the effect of human skin surface lipids upon the activity of antimicrobial agents is it time for brushless scrubbing with an alcohol-based agent? efficacy evaluation of a 4% chlorhexidine gluconate solution as a full body shower wash astm) method e 1052-96, a standard test method for efficacy of antimicrobial agents against viruses in suspension ), fifth author p. maheshwari's academic designation was presented incorrectly. the author's designation should have appeared as follows key: cord-314206-caxz025z authors: roberge, raymond j.; coca, aitor; williams, w. jon; powell, jeffrey b.; palmiero, andrew j. title: reusable elastomeric air-purifying respirators: physiologic impact on health care workers date: 2010-03-01 journal: am j infect control doi: 10.1016/j.ajic.2009.11.006 sha: doc_id: 314206 cord_uid: caxz025z background: elastomeric air-purifying respirators offer the benefit of reusability, but their physiological impact on health care workers is unknown. methods: ten health care workers exercised at 2 health care-associated work rates wearing an elastomeric air-purifying respirator. mixed inhalation/exhalation respirator dead space gases (oxygen, carbon dioxide) were sampled, and physiological parameters were monitored (heart rate, breathing rate, tidal volume, minute volume, oxygen saturation, transcutaneous carbon dioxide). numerical rating scales were used to evaluate comfort and exertion. results: compared with controls (no respirator), significant decreases in the breathing rate at both work rates (p < .05) and increases in tidal volume at the lower work rate (p < .01) were noted with respirator use. approximately half the subjects had transcutaneous carbon dioxide levels above the upper limit of normal after 1 hour of use. although well tolerated, comfort was negatively impacted by elastomeric air-purifying respirators wear. conclusion: reusable elastomeric air-purifying respirators impose little additional physiological burden over the course of 1 hour at usual health care work rates. however, the potential for carbon dioxide retention in a significant proportion of users exists and requires further investigation. the current pandemic influenza and previous experience with other respiratory infectious outbreaks (eg, avian influenza, severe acute respiratory syndrome) have raised concerns about the availability of disposable n95 filtering face piece respirators (n95 ffrs). given the very real possibility of n95 ffr shortages, elastomeric air-purifying respirators (eaprs) for health care workers (hcws) have been suggested as one alternative. 1 these are reusable, air-purifying respirators with face pieces made of pliable materials (eg, silicone, rubber, plastic) that employ 1 or 2 particulate filters and come in full face piece or half-mask models, of which the latter is the more commonly used in health care. 2 compared with disposable n95 ffrs, eaprs offer advantages that include improved face seal (for some wearers), easier donning and doffing, enhanced user seal check capability, ability of the face piece to be decontaminated multiple times, capacity for use by single or multiple hcws, and potential cost savings during a pandemic. [2] [3] [4] [5] widespread use of eaprs in the health care industry has not occurred, 5 and little is known about their physiological impact on hcws. this study, part of a larger investigation of multiple types of respiratory protection equipment that was carried out over 6 months, 6 was undertaken to determine the physiological burden imposed on hcws when wearing an eapr. ten hcws (7 women, 3 men), none of whom had previously used an eapr, were recruited. demographic variable means included the following: age, 25.1 years; body weight, 76.0 kg; height, 169.1 cm; and body mass index, 26.4. nine subjects had never smoked, and 1 subject had not smoked in .1 year (20 pack year smoking history). the study was approved by the national institute for occupational safety and health's human subject review board, and all subjects provided oral and written informed consent. physiological parameters (heart rate, breathing rate, tidal volume) were monitored with the lifeshirt ò system (vivometrics, ventura, ca), a lightweight spandex vest incorporating physiological sensors and circumferential respiratory inductive plethysmography (rip) bands. minute ventilation was calculated as the product of breathing rate 3 tidal volume. the lifeshirt ò was calibrated against a fixed volume immediately prior to each trial. oxygen and carbon dioxide concentrations (percentage) in the eapr dead space were sampled at 18 samples/second (total sampling volume of 500 ml/ min) via a 2-mm internal diameter sampling line attached to a port in the eapr face piece (positioned equidistant between nares and mouth) that directed samples to gas analyzers (aei technologies, naperville, il). the gas analyzers were calibrated before each trial with gas mixtures weighed into the cylinder using a balance that has been calibrated with weights that are certified to the national institute of standards and technology standards. 7 continuous oxygen saturation and transcutaneous carbon dioxide values were obtained with the tosca 500 monitor (radiometer, copenhagen, dk), a heated (428c) combination pulse oximeter and severinghaus-type pco 2 sensor that is earlobe mounted. the unit was calibrated over a 10-minute period immediately prior to use. a single model eapr (north 5500; north safety, providence, ri) that incorporates 2 p-100 filters was selected for the study because it had previously been shown to be well tolerated by hcws 8 (fig 1) . to ensure proper fit, quantitative respirator fit testing was carried out with the portacount ò plus (tsi, shoreview, mn). all subjects attained fit factors $100 (ie, ratio of ambient particles to within-face piece particles), indicating #1% leakage, the level required by the occupational health and safety administration for half mask respirators. 9 subjects donned the lifeshirt ò and were tested in athletic shorts, tee shirts, and athletic shoes (no headgear of any type [eg, caps, head nets, or others] was worn). the eapr was donned according to the manufacturer's instructions, negative and positive user seal checks 10 were carried out with the sample line pinched off, and the tosca 500 sensor was attached to the left earlobe. subjects were exercised for 1 hour (cumulative length of respiratory protective equipment use per shift by nursing staff 11 ) in a randomized fashion at each of 2 treadmill rates representative of hcw activities 12 that have been used in other studies 13, 14 : (1) 1.7 mph (2.74 km/h) treadmill speed (0% grade) that equates to stationary work (eg, writing nursing notes, using a telephone, and others) and (2) 2.5 mph (4.03 km/h) treadmill speed (0% grade) that equates to some bedside nursing patient care activities. data were compared to 15-minute control values (no eapr use) for the same subjects, at the same randomized work rates, and obtained no more than 3 weeks prior (15-minute values were considered valid for control purposes because, at relatively low intensity steady state exercise, steady state respiratory parameters are achieved in 3-6 minutes in healthy subjects 15, 16 ). numerical rating scales (ie, modified borg rating of perceived exertion [numerical range, 0-5; least to most exertion 17 ]; modified perceived comfort scale [numerical range, 1-5; most comfortable to least comfortable 18 ]) were utilized for subjective evaluations of exertion and comfort. speaking was allowed ad lib by subjects throughout the trials to mimic hcw communicating with staff, patients, and visitors. at the end of each trial, subjects filled out questionnaires related to any subjective sensations experienced (eg, facial heat, sweating, and others) or design features (pinching, odor, and others) causing discomfort. eaprs were weighed pretrial and post-trial to determine moisture retention. a new eapr was utilized for each of the 2 sessions, and there was a minimum 30-minute respite between sessions. the study laboratory average temperature was 21.768c (range, 20.18c -22.48c) and the relative humidity averaged 58.3% (range, 47.4%-71.5%). all physiological data and respirator dead space co 2 and o 2 data are reported as means (standard deviation). the time of the sessions is 1 hour, and all variables are reported as mean 1-minute values at 5 time increments (1, 15, 30, 45 , 60 minutes [tables 1 and 2]). one-hour averages were used for the statistical analysis because no significant changes over time were observed at the individual time increments. to assess differences between the eapr and controls at the 2 intensity levels during 1 hour of exercise, a 1-way (4 conditions) repeated measures analysis of variance (anova) was performed. to determine differences for physiological variables, repeated-measures anovas for oxygen saturation, partial pressure of transcutaneous carbon dioxide, breathing rate, tidal volume, minute volume, and heart rate were performed. significant differences were further analyzed utilizing pair-wise comparisons tests with least significant differences adjustments with the a level set at p 5 .05. paired t tests were performed to examine respirator dead space oxygen and carbon dioxide responses to eapr at the 2 exercise intensities. exertion scores, comfort scores, and eapr weights were analyzed by paired t tests. spss version 16.0 (spss, inc., chicago, il) was used for statistical analyses. all subjects were able to complete all trials. compared with controls, the eapr resulted in significant decreases in breathing rate at both work rates and significantly increased tidal volume at the 1.7-mph work rate; otherwise, there were no statistically significant differences in measured physiological variables (tables 1 and 2) there were no significant differences in mean mixed inhalation/exhalation respirator dead space carbon dioxide concentrations at 1.7 mph and 2.5 mph (p 5 .61) or respirator dead space oxygen concentrations at 1.7 mph or 2.5 mph (p 5 .80) ( table 2 ). there were no significant differences between controls and eapr in mean exertion scores at 1.7 mph (p 5 .67) and 2.5 mph (p 5 .96), mean comfort scores (p 5 .67 for both comparisons), or eapr moisture retention (p 5 .72) ( table 3) . subjective complaints and eapr features associated with discomfort are listed in table 3 . the study data indicate that the use of an eapr by healthy hcws, over 1 hour at work rates associated with the health care environment, was associated with statistically significant decreases in the breathing rate at 1.7 mph (p 5 .02) and 2.5 mph (p 5 .03) that was compensated by a significant increase in the tidal volume at 1.7 mph (p 5 .009) and nonsignificant increase at 2.5 mph (p 5 .14) compared with controls (table 3) . this is not unexpected because all respirators alter breathing patterns, and the increased ventilation associated with the (generally) greater dead space of the eapr compared with ffrs (eg, n95 ffr, and others) usually employed by hcws, favors an increase in tidal volume over breathing rate because it is more efficient from an energy standpoint. 19 a recent review concluded that respirator use has little impact on minute volume during resting or low-intensity work conditions like those normally encountered in health care environments. 20 mean absolute increases in transcutaneous carbon dioxide with the eapr at 1.7 mph (13.2 mm hg) and 2.5 mph (12.1 mm hg) were not significantly different from controls (p 5 .09, p 5 .27, respectively). of concern is the finding that mean transcutaneous carbon dioxide levels, averaged over the course of the last 15 minutes of the eapr use, were elevated (ie, .45 mm hg) in 4 of 10 subjects at the 1.7-mph work rate (range, 46-56 mm hg) and 5 of 10 subjects at the 2.5-mph work rate (range, 45.4-62.8 mm hg), despite the eapr being equipped with an exhalation valve that presumably allows for a smaller proportion of the exhaled breath (and associated carbon dioxide) to be retained in the respirator dead space (all subjects were asymptomatic of hypercapnia). 21 furthermore, at the 2 work rates, the mean mixed inhalation/exhalation respirator dead space oxygen concentrations (17.85%, 17.81%, respectively) and respirator dead space carbon dioxide concentrations (2.50%, 2.47%, respectively) did not meet occupational health and safety administration ambient workplace standards (ie, ,19.5% is considered oxygen deficient; maximum 0.5% carbon dioxide as an 8-hour time weighted average), 22 although these standards apply to the workplace, not to respirators. oxygen saturation was not adversely affected. nonetheless, this raises concerns that extended continuous eapr wear (.1 hour) might lead to further increases in transcutaneous carbon dioxide that could be deleterious to the wearer. also, the impact of mild-to-moderate eaprassociated increased retention of carbon dioxide upon specific subgroups of hcws who might be more susceptible to hypercapnia (eg, pregnant, asthmatics, and others) needs to be considered. although the use of other air-purifying respirators (ie, gas masks) for upwards of 2 hours by pregnant women in active labor without adverse effects on mother or fetus has been reported, 23 as has tolerance to eapr use by controlled asthmatics over short periods of mild-to-moderate work activities, 24 data are scarce overall. comfort is an important determinant of compliance with the use of respiratory protective equipment. 8 in the current study, mean comfort scores with the eapr were low (indicating less discomfort) and were not significantly different from controls at either work rate, suggesting that eaprs are reasonably comfortable. part of this comfort may be related to the low exertion work rates employed in this study, as supported by the fact that no significant differences were noted in the (low) mean exertion scores reported when comparing controls and eapr use at either work rate. furthermore, recent findings on hcws respirator tolerance (a measure of comfort) reported that the same model of an eapr as used in the current study was tolerated, on average, for 6.8 hours of use. 8 nonetheless, numerous complaints were offered by the current study subjects regarding subjective symptoms and design features ( table 3 ) that lend some credence to other recent findings that an eapr, although tolerable, has a greater adverse subjective impact on wearers than n95 ffrs. 24 moisture retention in respiratory protective equipment has been anecdotally suggested as a possible mechanism for increased respirator breathing resistance with prolonged use because of trapping of moisture in filter pores 4,25,26 but has not been subjected to scientific scrutiny of any significant degree. although no significant differences in moisture retention were noted at the 2 work rates (p 5 .72), we did not perform airway pressure measurements and cannot comment on any physiological effect of the moisture retention. we observed that there was significant moisture on the inner surface of the eapr, including the exhalation valve, no doubt related to the relatively nonporous nature of the materials. limitations of the current study include the relatively small sample size (n 5 10). there are many differences between this model and the many eaprs available on the market with respect to materials (eg, silicone, rubber, plastic), price, size, weight, tethering device configuration, filters and performance so that we are unable to generalize our findings to other eaprs. the study subjects had no prior experience with an eapr, and that could have negatively impacted performance, but this may be a more plausible study group given that most hcws have not had experience with eaprs. 6 the use of rip for ventilation data is subject to intra-and interpersonal variability 19 and is not as reliable as standard laboratory monitoring equipment (eg, spirometer, pneumotachygraph), but refinements in rip have led to improved accuracy in recent exercise studies. 27, 28 similarly, transcutaneous carbon dioxide levels are not as precise as arterial measurements, but improvements in sensors have led to greater precision, 29, 30 and this technique is not discomforting to the subject and avoids needle puncture-associated complications. last, the current study was not carried out in a health care facility; however, laboratory studies have been suggested as actually representing the upper boundary of study parameter measurements. 24 compared with controls over the course of 1 hour at 2 work rates associated with the health care environment, eapr use by hcws results in a lower breathing rate and compensatory higher tidal volume. absolute increases in transcutanous carbon dioxide levels over control values were not statistically significant over the course of 1 hour and not associated with symptomatology of hypercapnia, but variable retention of carbon dioxide occurred in a significant proportion of subjects and is a cause for concern. this will have to be evaluated further in a larger study and over more prolonged periods of continuous use. subjective ratings indicated that, although an eapr was tolerable over 1 hour and not associated with significant perceptions of exertion, comfort was negatively impacted. occupational safety & health administration. pandemic influenza preparedness and response guidance for health care workers and healthcare employers personal respiratory protection against mycobacterium tuberculosis avian influenza pandemic procurement recommendations for the us federal government reusability of facemasks during an influenza pandemic: facing the flu the role of masks in preventing nosocomial transmission of tuberculosis national institute for occupational safety and health. impact of respirator use on co 2 levels and o 2 saturation fy handbook 105-1; specifications and tolerances for reference standards and field standard: weights and measurements (revised respirator tolerance in health care workers (research letter) occupational safety & health administration. fit testing procedures 29 cfr 1910 user seal check procedures (mandatory): 29 cfr 1910:134 app.b-1 what do healthcare workers think? a survey of facial protection equipment user preferences compendium of physical activities: an update of activity codes and met intensities effects of wearing n95 and surgical facemasks on heart rate, thermal stress and subjective sensations evaluation on masks with exhaust valves and with exhaust holes from physiological and subjective responses exercise responses during incremental and high intensity and low intensity steady state exercise in patients with obstructive lung disease and normal control subjects ventilatory patterns during steady state and progressive exercise borg's perceived exertion and pain scales examining an affective aggression framework: weapon and temperature effects on aggressive thoughts, affect, and attitudes the physiological cost of wearing a disposable respirator workplace breathing rates: defining anticipated values and ranges for respirator certification testing physiologic and subjective effects of respirator mask type physiologic effects and measurement of carbon dioxide and oxygen levels during qualitative respirator fit testing does the gas mask jeopardize the fetus? multidomain subjective response to respirator use during simulated work survey and evaluation of modified oxygen delivery devices used for suspected severe acute respiratory syndrome and other high-risk patients in hong kong a century after their introduction, are surgical masks necessary? assoc oper room nurses measurement of exercise ventilation by a portable respiratory inductive plethysmograph monitoring of ventilation during exercise by a portable respiratory inductive plethysmograph use of transcutaneous oxygen and carbon dioxide tensions for assessing indices of gas exchange during exercise testing accuracy of transcutaneous carbon dioxide tension measurements during cardiopulmonary exercise testing. respiration (epub ahead of print) key: cord-301988-cevv81h3 authors: hassoun, ali; huff, matthew d.; weisman, david; chahal, khushdeep; asis, esmeralda; stalons, don; grigorenko, elena; green, jessica; malone, leslie l.; clemmons, scott; lu, stanley title: seasonal variation of respiratory pathogen colonization in asymptomatic health care professionals: a single-center, cross-sectional, 2-season observational study date: 2015-08-01 journal: am j infect control doi: 10.1016/j.ajic.2015.04.195 sha: doc_id: 301988 cord_uid: cevv81h3 background: the purpose of this study was to determine the seasonal variance of potentially pathogenic bacterial and viral organisms in nasopharyngeal specimens obtained from asymptomatic health care professionals (hcps) during the 2014 winter and summer months. methods: nasopharyngeal specimens from 100 hcps were collected from huntsville hospital (huntsville, al) during the winter and from 100 hcps during the summer. all subjects were tested for 22 viruses and 19 bacteria using target enriched multiplex polymerase chain reaction. both seasonal cohorts were composed of students, nurses, physicians, and residents. results: of the 100 hcps tested during the winter, 34 subjects were colonized with at least 1 bacterium, and 11 tested positive for at least 1 virus. methicillin-resistant staphylococcus aureus (mrsa), moraxella catarrhalis, and coronavirus were the most frequently detected potentially infectious agents. of the 100 hcps tested during the summer, 37 tested positive for at least 1 bacterium, and 4 tested positive for a viral agent. the most prevalent bacteria were mrsa and klebsiella pneumonia. conclusion: nasopharyngeal carriage among asymptomatic hcps was common, but the frequency and presence of potential pathogens varied with each season. understanding the colonization and infection potential of upper respiratory organisms is important, particularly for viruses. although asymptomatic hcps certainly harbor a number of different potentially infectious agents, future studies are needed to determine whether colonized pathogens are transmitted or initiate infection in at-risk patient populations. within healthy subjects, the upper respiratory tract fosters a complex, commensal microbiome. 1, 2 however, introduction of a foreign bacterial or viral organism into the microbiologic community may disrupt normal intercellular relationships resulting in an imbalanced ecosystem. [1] [2] [3] the detailed mechanisms that drive these complex interactions are largely unknown; consequently, it is difficult to predict the behavior of this highly nonlinear system. downstream consequences can be influenced by activities of other organisms, use of antimicrobials, or the host's immune response. 1 in immunocompromised subjects, such as neonates, elderly adults, and patients undergoing chemotherapy, the addition of an unfamiliar pathogen can offset the delicate equilibrium and increase the likelihood of pathogenic invasion. 2 in individuals with functional immune systems, internalized microbes are eliminated, whereas noninternalized pathogens can thrive within the respiratory microbiome, thereby using their hosts as vectors. however, these asymptomatic individuals can still pose a threat of transmitting the potentially pathogenic agent to at-risk subjects. target enriched multiplex polymerase chain reaction (tem-pcr; diatherix laboratories, huntsville, al) simultaneously detects 22 viral serotypes and 19 bacterial species that often inhabit the upper respiratory tract. this multiplex assay is performed from a single patient specimen and has high levels of specificity and sensitivity (table 1) . little is known about the colonization rates of respiratory pathogens in asymptomatic adult subjects, especially for viruses. here, we describe the frequency and seasonal variation of bacterial and viral detections in asymptomatic health care professionals (hcps) during the winter and summer months of 2014. seasonal variation of infectious disease rates is a common phenomenon that is clearly manifested when temperatures are at extremes; consequently, there may be seasonality of colonization levels and commensal relationships of pathogens in asymptomatic individuals. 4 by elucidating changes in pathogen colonization rates in asymptomatic hcps during different time periods in the year, health care organizations can monitor which potentially pathogenic agents are most prevalent in carriers in a health care setting and observe correlations with infection levels in at-risk hospitalized patients. 5 new mechanisms of pathogen transmission can be hypothesized and tested, which could be potentially important in a clinical setting and have a positive effect on infection control practices. two hundred hcps, consisting of 100 during the winter and 100 during the summer, from huntsville hospital (huntsville, al) were tested for the presence of respiratory pathogens via tem-pcr. hcp categories included medical students, nurses (intensive care unit and general patient care), physicians, and residents. pertinent histories, including recent upper respiratory symptoms and antibiotic use, were obtained. all 200 hcps were asymptomatic for a minimum of 4 weeks before samples were taken. each hcp completed a questionnaire that evaluated their respiratory status. questionnaires were reviewed by physicians at huntsville hospital, and it was determined that none of the subjects likely had current infections during specimen collection intervals. none of the physicians who participated in the study reviewed the surveys. eligibility criteria required hcps be free of respiratory symptoms for at least 4 weeks prior to specimen collection and agree to provide a nasopharyngeal specimen for testing. nasopharyngeal specimens were collected in 2014 during january-february and june-july, representing the winter and summer observations, respectively. specimens were sent via courier to diatherix laboratories. results were sent to the study coordinator at huntsville hospital within 24 hours of sample receipt, and study participants were notified of the results. nucleic acid extraction for tem-pcr was performed using a kingfisher system (thermo fisher scientific, waltham, ma). the amplification steps were completed using a geneamp pcr system 9700 thermal cycler (applied biosystems, thermo fisher scientific, waltham, ma). probe fluorescence was read using a sensospot flair system (sensovation, radolfzell am bodensee, germany). a more detailed description of specimen collection and transport conditions, tem-pcr technology, and analytical validation of the assay are included in the supplemental data. all tem-pcr results were organized and extracted from a reporting database at diatherix laboratories using microsoft sql . the 100 hcps tested during the 2014 winter months consisted of 18 medical students, 33 nurses, 6 physicians, and 43 residents. the 100 hcps tested during the 2014 summer months consisted of 16 medical students, 47 nurses, 5 physicians, and 32 residents. the 2 sample groups were nonoverlapping. prior to the 4-week asymptomatic period, 34 of the 200 subjects had symptoms of a respiratory illness, and 14 of the 200 received antibiotic treatment. a more detailed description of the subject sample is shown in table 2 . figure 2 displays a summary of the respiratory pathogen detection percentage partitioned by profession and season. in the winter, residents represented the subset of hcps with the largest frequency of colonization because 26 (60.5%) of the 43 were positive for at least 1 bacterial or nonbacterial pathogen. however, the highest proportion of viruses was seen in nurses because 7 (21.2%) of the 33 tested were detected with coronavirus. in the summer, as in winter, residents had the highest frequency of detection because 14 (43.8%) of the 32 tested were positive for at least 1 pathogen. nurses exhibited a slightly lower level of colonization because 19 (46.3%) of the 41 had at least 1 pathogen detection. figure 3 characterizes all of the hcps in both seasons that had a codetection for 2 genetic targets. a larger number of subjects exhibited codetections during the winter because 12 (25.5%) of the 47 subjects were detected with 2 genetic targets. of the 19 positive detections for mrsa, 4 (21.1%) were positive for the panton-valentine leukocidin (pvl) cytotoxin gene, which represented the highest frequency of simultaneously detected genetic targets. eight (30.8%) of the 26 residents had >1 detection. in the summer, 1 resident had 3 bacterial detections, whereas no hcps in the winter exhibited >2 detections. supplemental figures s1 and s2 display the detection percentage aggregated by sex and season and age groups and season, respectively. men had a marginally higher frequency of detection because 16 (51.6%) of 31 in the winter and 19 (52.8%) of 36 in the summer had at least 1 pathogen detection. in the winter, the 30-40 years age bracket had the highest percentage of detection because 16 (55.2%) of the 29 hcps tested were positive for at least 1 bacterium or virus. in the summer, 19 (52.8%) of 36 subjects in the 20-30 years age bracket had the largest percentage of pathogen detection. figure 2 and supplemental figures s1 and s2 present data as a percentage of positive detection out of total tests given to a specific profession, sex, or age during each season. supplemental tables s1-s3 display the number of positive detections and number of tests given. during the winter, hcov was detected in 11 of the 100 asymptomatic hcps. one study reported results comparable with the 11% hcov detection frequency found in hcps at huntsville hospital. 6 taiwan and found that 25 (11.5%) were colonized with sars-cov. 6 the nosocomial spread of sars-cov in large hospitals was a major epidemic feature during early stages of the outbreak, but this problem was resolved after hospitals isolated all symptomatic patients and asymptomatic hcps detected with sars-cov. 7 all 11 detections for hcov at huntsville hospital also came from frontline asymptomatic hcps, predominantly nurses. observations from this study and the ho et al study suggest that coronavirus could possibly be spread from infected patients to frontline hcps through close contact or via contaminated droplets, but further studies are needed to substantiate this hypothesis. m catarrhalis exhibited seasonal variation because 11 hcps tested in the winter were positive, but all subjects were negative in the summer. the presence of m catarrhalis was unexpected because colonization usually only occurs in children, and only 3% of healthy adults are colonized. 8 the high winter detection frequency of m catarrhalis observed could be a result of the temperaturedependent characteristics of the organism. at lower temperatures, the speed of transcription and abundance of mrna transcripts increases, m catarrhalis grows and divides at a more rapid rate, and the organism's pathogenic behavior has a higher probability of being activated. 9,10 m catarrhalis can live commensally for extended periods; therefore, the incubation time of this organism is not well defined. however, m catarrhalis can become pathogenic in subjects with compromised immune systems or in subjects that have experienced nasopharyngeal stress, such as patients with chronic obstructive pulmonary disease. 11 as a result, it may be valuable to determine which hcps are colonized with m catarrhalis and determine whether there is a correlation with infection rates in at-risk patients. 12 s aureus and mrsa were frequently detected in both winter and summer. the high prevalence of healthy subjects colonized with s aureus and mrsa has been well described. 13 commonly, s aureus and mrsa act as commensals of the upper respiratory tract, but if a patient is immunocompromised, a potentially fatal infection can develop. as a result, many hospitals implement s aureus and mrsa infection reduction protocols and use active surveillance programs to decolonize patients before admission or surgery. 14 s aureus and mrsa also attack the lower respiratory tract where organisms are often parasitic and cause bacterial pneumonia. 15 in this study, 4 hcps in the winter and 1 hcp in the summer were colonized by pvl-positive mrsa. pvl is a potent cytotoxin produced by s aureus that causes necrotizing pneumonia with a high mortality rate. 16 many hospitals have already implemented decolonization procedures for patients colonized with s aureus and mrsa, but future studies could support the decolonization of asymptomatic hcps. k pneumoniae was the only organism that demonstrated a substantially higher frequency of colonization in the summer. summer detection was anticipated because the prevalence of k pneumoniae infections, especially bloodstream infections, increases during the summer. 17, 18 the seasonal variation in k pneumoniae colonization is not well understood. it has been reported that higher rates of k pneumoniae colonization are primarily related to the use of antibiotics. here, only 1 (14.3%) of the 7 hcps that were colonized with k pneumoniae recently received antibiotics. 19 k pneumoniae can be easily and rapidly transmitted to immunocompromised patients from the hands of contaminated hcps. 5 similar to pvl-positive s aureus and mrsa, k pneumoniae can also infect to the lower respiratory tract causing abnormalities such as bulging interlobar fissures, cavitary abscesses, and necrotizing pneumonia. 20, 21 as a result, detecting and decolonizing the carriers of k pneumoniae could have a positive impact on reducing high-risk transmission and hospital-acquired infections during the summer, particularly in patients with comorbidities. there are only a small number of studies reporting the detection frequency of viruses, particularly in asymptomatic adults, which makes it difficult to compare our results with other findings. five different viruses, including adenovirus, coronavirus, rhinovirus, coxsackievirus-echovirus, and pandemic influenza a h1n1-09, were detected at least once in either or both seasons. there are few studies that investigate the effects of viral colonization or coinfections in the upper respiratory tract. previous reports show that the prevalence of viral pathogens may increase bacterial colonization and risk of infection in the nasopharynx. 22 in addition, 1 study proposed a colonization-competition model for rna viruses and predicted that low-virulence strains initially colonize human cells and then competitive, high-virulence strains prime the nasopharynx for infection. 23 multiplex polymerase chain reaction technology can help add to these models and better define the unknown mechanisms of colonization and infection of viral pathogens. one property of tem-pcr is that it amplifies dna or rna of both viable and nonviable organisms. presumably, many of the hcps in this study had respiratory diseases long before this study and could be conveying nucleic acid remnants that were detected by tem-pcr. the 4-week clearance period (as previously described in the methods section) was intended to reduce the likelihood of this possible false detection; however, the half-life of nucleic acid fragments in this setting is not known. it is almost certain that rna remnants degrade more quickly than dna. 24 in the winter, a larger proportion of hcps had prior respiratory symptoms, which may have been responsible for the higher frequency of pathogens detected in this season. further testing methods, such as culture, would need to be conducted to discriminate between nucleic acid remnants and viable microorganisms. it is also possible that the high sensitivity of multiplex polymerase chain reaction detected recent invader cells that would later cause disease in the hcp. however, for the purposes of this study, we do not discriminate between long-standing colonies and recent invader cells because both scenarios can plausibly spread pathogens to at-risk patients. this study examined a moderately sized sample, and the proportions of professions, sexes, and ages varied during each season. in addition, medical students, physicians, and residents worked in diverse sections of the hospital, but nurses only worked in either the intensive care unit or the general population. a larger proportion of nurses tested during both seasons worked in the intensive care unit (26 [78.8%] in the winter, 29 [61.7%] in the summer), which could have been the reason for moderately high pathogen detection frequency in this subset. information was unavailable to determine the proportion of time each hcp treated patients while wearing a mask. not wearing masks would increase the likelihood of transmission from patient to hcp and vice versa. even though this study focuses on hcp colonization, the identification and management of all possible pathogen reservoirs, such as health care surfaces, equipment, and colonized visitors, are also important for preventing the spread of infection in a clinical setting. 5 nevertheless, the utilization of a sensitive and specific multiplexing nucleic acid assay is valuable because the assay detects multiple viral and bacterial pathogens simultaneously in asymptomatic subjects. colonization of viral pathogens needs substantially greater understanding, and defining the unknown colonization and infection potential of these upper respiratory organisms is important. this preliminary observational study explores the prevalence of colonization of various pathogens at 2 different points in the year, and if validated with larger follow-up studies, this information could be ultimately relevant in the clinic. determining correlations between levels of hcp colonization and at-risk patient infection rates could assist in defining novel transmission pathways. in turn, hospital protocols could be altered so that colonized hcps and at-risk patient interactions could be managed, threat of transmission could be minimized, and infection control protocols could be optimized. microbial interactions during upper respiratory tract infections bacterial interference in upper respiratory tract infections: a systematic review respiratory microbiota: addressing clinical questions, informing clinical practice seasonal infectious disease epidemiology hospital epidemiology and infection control in acute-care settings colonization of severe acute respiratory syndrome-associated coronavirus among health-care workers screened by nasopharyngeal swab fighting the sars epidemic in taiwan: a nursing perspective branamella catarrhalis in children and adults. a study of prevalence, time of colonization, and association with upper and lower respiratory tract infections moraxella catarrhalis-pathogen or commensal? physiologic cold shock increases adherence of moraxella catarrhalis to and secretion of interleukin 8 in human upper respiratory tract epithelial cells moraxella catarrhalis in chronic obstructive pulmonary disease: burden of disease and immune response outbreak of moraxella catarrhalis in a respiratory unit the management of infection and colonization due to methicillin-resistant staphylococcus aureus: a cids/camm position paper eradication or decolonization of methicillin-resistant staphylococcus aureus carriage: what are we doing and why are we doing it? pneumonia caused by methicillinresistant staphylococcus aureus panton-valentine leukocidinproducing staphylococcus aureus outbreak of multidrug-resistant klebsiella pneumoniae carrying qnrb1 and blactx-m15 in a french intensive care unit seasonal variation in klebsiella pneumoniae bloodstream infection on 4 continents outbreak of a multiresistant klebsiella pneumoniae strain in an intensive care unit: antibiotic use as risk factor for colonization and infection rapidly fatal outcome of bacteremic klebsiella pneumoniae pneumonia in alcoholics community-acquired klebsiella pneumoniae. bacteremia: global differences in clinical patterns increased pharyngeal bacterial colonization during viral illness competition-colonization dynamics in an rna virus primordial soup or vinaigrette: did the rna world evolve at acidic ph? we thank all health care professionals at huntsville hospital who participated in this study and all practitioners who collected health care professional nasopharyngeal specimens. in addition, we thank all diatherix clinical laboratory employees who conducted the 200 tem-pcr respiratory panel tests for this study. special thanks to donna hockman, who was one of the pioneer designers for diatherix's current respiratory panel. finally, we thank brint roden for generating the graphical abstract and jessica l. alleyne, blake adams, michelle hammond, and vicki caneer for proofreading manuscript drafts. supplementary data related to this article can be found at http:// dx.doi.org/10.1016/j.ajic.2015.04.195. key: cord-302761-yila2wht authors: mcquerry, meredith; easter, elizabeth; cao, alex title: disposable versus reusable medical gowns: a performance comparison date: 2020-10-20 journal: am j infect control doi: 10.1016/j.ajic.2020.10.013 sha: doc_id: 302761 cord_uid: yila2wht background: medical gowns are essential personal protective equipment (ppe) that prevent the spread of microorganisms and bodily fluids. during surge capacity situations, such as the covid-19 pandemic, reusable ppe is often recommended due to shortages. methods: this research evaluated the performance of disposable versus reusable medical gowns by assessing their ability to provide adequate protection across their expected service lifespan. level i, ii, & iii gowns were tested for water resistance and hydrostatic pressure, along with other durability assessments (breaking, tear, and seam strength, pilling resistance, dimensional stability, air permeability, colorfastness, and fabric hand) per standard test methods. data was collected at new for the disposable gowns and after 1, 25, 50, and 75 industrial launderings for the reusable gowns. results were compared to aami pb70 performance specifications. results: level i and ii disposable gowns did not meet aami performance specifications for impact penetration water resistance. all three levels of disposable gowns also failed to meet astm performance requirements for breaking strength in the crosswise direction. conclusions: the adoption of reusable gowns may result in increased protection and significant cost savings due to their superior durability and sustainability when compared to disposable gowns. as a result of the covid-19 pandemic, personal protective equipment (ppe) became a household term as many citizens were made aware of its significance in order to reduce community spread, as well as protect healthcare workers (hcws) on the front lines. ppe is defined as an "item of clothing that is specifically designed and constructed for the purpose of isolating all or part of the body from a potential hazard or isolating the external environment from contamination by the wearer of the clothing 1 . protective apparel is worn by hcws to inhibit the transfer of blood, body fluids, other potentially infectious materials (opm) and to help preserve the integrity of the sterile field. these garments are the hcw's only line of defense and protection from potentially deadly infectious diseases and viruses during patient care. a severe shortage in the amount of necessary ppe during the covid-19 pandemic caused concern for health care providers as they feared being infected by the patients they cared for and, in turn, passing the virus on to their own families 2 . a key part of healthcare workers' ppe are medical gowns, which include both isolation and surgical gowns. medical gowns have been identified as the second-most commonly used ppe item, following gloves, in healthcare settings [3] [4] [5] . according to the association of the advancement instrumentation® (aami), an isolation gown is an "item of protective apparel used to protect health care personnel and patients from the transfer of microorganisms and body fluid in patient isolation situations" 1 . surgical gowns are defined by the united states (us) food and drug administration (fda) as "… devices that are intended to be worn by operating room personnel during surgical procedures to protect both the surgical patient and the operating room personnel from the transfer of microorganisms, body fluids…" 6 . medical gowns are rated according to aami standards, which define four levels of protection (levels 1, 2, 3, and 4). each protection level must meet specific standard performance requirements for impact penetration and hydrostatic pressure resistance, detailed in the aami pb70 standard for isolation and surgical gowns 1 . the level of protection, or classification of barrier performance, is determined by the performance of all critical zone components, including seams 1 . critical zones are defined by aami as areas "where direct contact with blood, body fluids, and other potentially infectious materials is most likely to occur" 1 . for surgical gowns, these zones should comprise the front area of the gown from chest to knees and the sleeves from cuff to elbow. the critical zones of isolation gowns, comprise the same areas as surgical gowns but include the entire gown, excluding cuffs, hems, and bindings 1 . therefore, the required protection testing should be performed in the critical zone areas of the gown. regardless of their disposable or reusable nature, l1 gowns must have an impact penetration (aatcc 42) < 4.5 g. l2 and l3 gowns must have an impact penetration < 1.0 g, as well as a hydrostatic pressure (aatcc 127) value > 20 cm for l2, and > 50cm for l3. it should be noted that l1 gowns are not required to be tested for hydrostatic pressure performance per aatcc 127 1 . both impact penetration and hydrostatic pressure tests are measures of liquid barrier performance with varying levels of force. the centers for disease control and prevention (cdc) currently issues recommendations regarding when and what level of ppe should be worn in order to prevent exposure to infectious diseases 7 . according to the cdc's guideline for isolation precautions, isolation gowns should be worn to protect hcws arms and other exposed areas during procedures and patient-care activities when contact with clothing, blood, bodily fluids, secretions, and excretions is anticipated 3,8 . 6 as the covid-19 pandemic continued, the cdc provided a series of strategies or options to optimize the use of medical gowns in healthcare settings when supplies were limited, known as 'surge capacity'. the cdc defines surge capacity as "the ability to manage a sudden, unexpected increase in patient volume that would otherwise severely challenge or exceed the present capacity of a facility" 9 . in march of 2020, the cdc recommended gown use be shifted towards "cloth gowns," stating that reusable (i.e. washable) gowns are typically made of polyester or polyester-cotton fabrics, unlike most disposable gowns which are constructed from nonwoven materials 9 . gowns made of these fabrics can be safely laundered according to routine procedures and are, therefore, reusable 10 . a major challenge of the cdc's recommendation to adopt reusable gowns during surge capacity is that cloth gowns have a much lower market share than disposable gowns in us healthcare. presently, disposable gowns make up at least 80% of the isolation gown market (jenkins, 2018) . however, this market share trend is expected to change over time in favor of reusable gowns. especially as the protection of disposable gowns has been called into question after recent epidemics such as the ebola crisis of 2014 which claimed the lives of over 11,000 people, including 500 healthcare personnel. following this crisis, in 2016 it was found that some medical gowns on the market were defective, allowing fluids to leak through, ultimately infecting surgeons and nurses in contact with infected patients 11 . previous research has highlighted the sustainability of reusable gowns noting they are more cost-effective throughout their life cycle in terms of production costs, waste, and carbon footprints, [12] [13] [14] [15] . limited studies, however, have been conducted on the required protective performance and durability of reusable surgical gowns over their useful life, specifically across the wash lifespan. leonas (1998) assessed the barrier properties of reusable gowns after 50 commercial care cycles and found that laundering reduced the ability of the fabric to prevent the transmission of bacteria 16 . higher barrier properties were found to correspond with higher degrees of repellency and greater fabric thickness (i.e., two-layers in some cases) 16 . besides this study, little research has been performed on reusable gowns after multiple commercial launderings, especially in regard to serviceability components beyond protection, including comfort, durability, and appearance retention. in addition, to the researchers' knowledge, no study has conducted a comprehensive performance comparison between disposable and reusable gowns across the wash lifespan. the purpose of this research was to determine the performance of disposable versus reusable medical gowns by assessing their ability to provide adequate protection, durability, and comfort across the product's wash lifespan. first and foremost, the ability of the gowns to meet required protection specifications per aami standards were investigated. commercially available level 1, 2, and 3 disposable, and level 2 and 3 reusable, gowns were evaluated using the american association of textile chemists and colorists (aatcc) test method (tm) 127 and aatcc tm 42. results were compared to aami pb70 and the american society for testing and materials (astm) performance requirements. the fabric weight, thickness, breaking strength, tearing strength, seam strength, pilling resistance, dimensional stability, colorfastness, air permeability, and fabric hand of the disposable and reusable gowns were also determined and compared. three levels of disposable gowns were included in this study, representing aami pb70 protection levels 1 (l1), 2 (l2), and 3 (l3). disposable gowns were sourced from a single supplier at each protection 1evel based on market availability. for the reusable gowns, only l2 and l3 gowns were included, based on the lack of availability of l1 reusable gowns currently on the market. the reusable gowns were sourced from two different suppliers for both protection levels (2 and 3), referred to as brand a and brand b in table 1 , which details each gown's fiber content, construction, protection level, and size. at minimum, five gowns of each gown type were purchased/sourced for this study. the disposable gowns were available for purchase in packs of 20, 50, and 100. the reusable gowns were purchased individually. all minimum sampling requirements were followed per standard test methods for this study such that the results are repeatable and reproducible. the number of samples and specimens taken from each gown type was dependent on the specific standard test method being conducted (i.e. three specimens for impact penetration, hydrostatic pressure, fabric weight, colorfastness, dimensional stability, four specimens for pilling resistance, five specimens for seam strength, and ten specimens for air permeability, breaking strength, tear strength, and thickness). insert table 1 here. laundering was performed according to standard medical gown wash procedures recommended by the cdc's guidelines for environmental infection control in health-care facilities [17] [18] [19] [20] . based on the above recommendations, the healthcare wash cycle utilized in this study included a hot wash at 71ºc for 25 minutes, a standard industrial laundry detergent, no bleach additive, and a supply of sour before the final rinse, drain, and spin. an 8 kg industrial unimac® washer was used to perform 75 wash cycles on the reusable gowns, the number of wash/dry cycles tracked by the manufacturers of the gowns in this study. the laundry load was made up of 16 gowns (4 reusable gowns of each type: two brands at two protection levels), plus additional reusable gowns, not intended for testing, in order to make a 5.5 kg load. this load size placed the 8 kg washer at 65% capacity, which was recommended due to the bulk of the load. drying between each wash cycle was conducted in an industrial unimac® dryer on warm (65-76ºc) for 30 minutes, providing additional significant microbiocidal action 17, 19 . the drying time was dictated by the polyester fiber content, which requires shorter dry times at lower temperatures 17 . after 1, 25, 50 and 75 washes, four reusable gowns (one of each type) were removed from the load and tested. new, unwashed gowns were used to replace the gowns removed for testing at each interval to maintain a consistent load weight. all test procedures were conducted according to standards published by aatcc and astm. before testing, the gowns were conditioned at (21 ± 1°c; 65rh ± 2%rh) for a minimum of 24 hours, according to astm d1776 standard practice for conditioning and testing textiles. gowns and specimens were stored under the same conditions between tests, and all testing was conducted under these conditions. non-destructive tests were performed first in order to conserve sample sizes for destructive methods. disposable gowns were tested only at new, based on their single-use application. reusable gowns were tested at new, where applicable, and after 1, 25, 50 and 75 industrial wash cycles. resistance: impact penetration test 21 . the purpose of this test is to measure the resistance of fabrics to the penetration of water by impact. the increase in the weight of the blotting paper was calculated and averaged. disposable gowns were tested at new while the reusable gowns were tested after 1, 25, 50, and 75 industrial wash cycles. aatcc test method 127-2017 water resistance: hydrostatic pressure test was used to measure the resistance of the gown fabrics to the penetration of water under hydrostatic pressure 22 . hydrostatic pressure was recorded at the moment water droplets penetrated the fabric in three separate places. water droplets that appeared within approximately 3 mm adjacent to the edge of the clamping ring were disregarded. this test was repeated such that three specimens from each gown were tested per the standard test method and the average hydrostatic pressure was recorded for each gown. in addition to the aami pb70 performance requirements, this study evaluated the durability, comfort, and appearance retention properties of medical gowns. these evaluations, outlined in table 2 , included fabric weight and thickness; breaking, tearing, and seam strength; air permeability and fabric hand; and dimensional stability, pilling resistance, and colorfastness. gowns intended for use in healthcare facilities, breaking, tear, and seam strength are included as performance requirements for both single and multiple-use isolation gowns 33 pilling resistance was conducted using a standard nu martindale tester. four specimens from each gown were subjected to 500 rubs and evaluated according to the astm photographic pilling rating scale which ranges from "1" indicating "very severe pilling" to "5" indicating "no the percent shrinkage or growth was calculated per the standard aatcc test method. utilizing aatcc evaluation procedure 5, the fabric hand, or feel, of all gowns were subjectively assessed by three individual raters on a scale from "1" to "7" for all 8 parameters (pliable (1) to stiff (7); soft (1) to hard (7); stretch (1) to non-stretchy (7); non-creased (1) to creased (7); company (1) to open (7); smooth (1) to rough (7); harsh (1) to slippery (7); cool (1) to warm (7)). visual assessment of color change was conducted on the reusable gowns by three raters, per the standard test method, to determine the appearance retention after 75 ils. the aatcc gray scale for color change was used to assign each gown a rating between "1" meaning "very severe color change," and "5," meaning "no color change." typically, a rating of "4" or greater is required to pass many consumer apparel astm performance specifications; however, colorfastness is not currently considered in current isolation and surgical gown performance specifications. to determine the variance and statistical significance between gown performance at new and after multiple wash intervals, one-way anovas were utilized, followed by two-sample t-tests, assuming equal variance, if significant differences were identified between gowns. the analysis was conducted utilizing the basic statistical software package available in microsoft excel. a pvalue of 0.05 was chosen to indicate statistical significance. fabric weight and thickness were measured at new for the disposable gowns and after 1, 25, 50, and 75 industrial launderings (ils) for the reusable gowns according to the astm standards listed in table 2 . the fabric weight and thickness for all gowns are provided in table 3 . fabric weights were significantly different (p < 0.05) between all three protection levels of the disposable gowns. for the reusable gowns, statistically significant differences (p < 0.05) were found for all gown pairs at all laundering intervals except between the l2 and l3 brand b gowns. the impact of industrial laundering did not affect fabric weight for any of the reusable gowns. insert table 3 here. thickness was significantly different (p < 0.05) between all three levels of disposable gowns, with thickness increasing as protection level increased. for the reusable gowns, statistically significant differences (p < 0.05) were found for all gown pairs at all laundering intervals except for between the brand a and brand b l3 gowns, which maintained almost identical thicknesses across 75 ils. however, unlike fabric weight, laundering significantly altered the fabric thickness of two of the reusable gowns (brand a-l3; and brand b-l2). for the brand b-l2 gown, thickness significantly decreased (p < 0.000) over 75 ils while for the brand a-l3 gown, it significantly increased (p = 0.004). impact penetration water resistance testing was conducted on all gowns to measure the resistance of the fabrics to the penetration of water by impact. the average increase in weight of the blotter paper, which reflects water penetration, is illustrated in figure 1a for the disposable gowns at new and in figure 1b for the reusable gowns at each laundering interval. of the disposable gowns, only the l3 gown met the aami pb70 requirements (< 1.0g) for impact penetration with the l1 and l2 gowns had an average increase in blotter paper weight of 16.2g and 13.5g, respectively. differences between all three disposable gowns were statistically significant (p < 0.05). for the reusable gowns, as shown in figure 1b , both protection l2 and l3 gowns met the minimum performance requirements (< 0.1g) for both brands. there were no statistically significant differences between gowns at any laundering interval and there were no significant differences between wash intervals, indicating impact penetration was not affected by the wash life of a reusable gown. hydrostatic pressure water resistance testing was also performed as required by aami pb70 for medical gowns. following aatcc tm127, the resistance of the gown fabrics to the penetration of water under hydrostatic pressure was measured. as shown in figure 2a , both the l2 and l3 disposable gowns met the minimum requirements for water column height during hydrostatic pressure testing. the l3 disposable gown had significantly greater hydrostatic pressure resistance than the l2 gown (p < 0.000). all reusable gowns, regardless of protection level or brand, met the minimum water column height requirements for aatcc tm127, as shown in figure 2b . both l3 reusable gowns reached the maximum mbar pressure of 1,000 cm on the hydrostatic head tester resulting in a calculated water column height of 1,019.72 cm for all test intervals. for the reusable gowns, statistically significant differences (p < 0.05) were found for all gown pairs at all laundering intervals except for the l3 gowns, which maintained the maximum hydrostatic pressure water resistance possible across 75 ils. for the lii reusable gowns, brand a maintained a significantly greater hydrostatic pressure resistance over the course of the gowns' wash life, as reflected in figure 2b . in addition, only the l2 gowns experienced any significant change in hydrostatic pressure over the course of the 75ils with brand a experiencing significant reductions in protection after each test interval (25, 50, and 75 ils). the brand b-l2 gown did not experience a significant reduction in hydrostatic pressure protection until after 75 ils. regardless of the significant differences between gowns, it should be reiterated that all reusable gowns in this study met the minimum performance requirements for hydrostatic pressure water-resistance after all test intervals through 75 ils. pilling resistance was conducted at new for the disposable gowns and after 1, 25, 50, and 75 ils for the reusable gowns. all reusable gowns in the study received an average score of "5," indicating no pilling after all wash intervals; therefore, industrial laundering did not impact pilling. the l1 and l2 disposable gowns did experience "severe" (2.75) and "very severe" (1. 11) pilling, respectively. in fact, after less than 500 rubs, an l2 gown specimen was destroyed due to abrasion and could not be visually rated. the l3 disposable gown received a rating of only "slight pilling" at 4.79, on average, and had significantly higher pilling resistance than the l1 (p = 0.04) or l2 (p = 0.000) disposable gowns. average air permeability results are shown in figure 4 and are reported as ft 3 /minute (cfm). there is no minimum performance expectation for air permeability in isolation or surgical gowns, however, the higher the value, the more air can pass through, enhancing wearer comfort. the disposable gowns had significantly higher (p < 0.05) air permeability than the reusable gowns, demonstrating a potential sacrifice in comfort and breathability for multiple-use gowns. for the front of the reusable gowns, which represents the critical zones, both l3 gowns had zero air permeability. the brand a-l2 gown had minimal to no air permeability, with the brand b-l2 gown having the highest air permeability at just 3.4-4.0 cfm. only the reusable gowns were measured for dimensional change as it is a determination of shrinkage or growth after laundering. brand a-l2 and a-l3 gowns experienced -2.41% and -1.60% shrinkage, respectively, while brand b-l2 and b-l3 gowns experienced -2.30% and -3.59% shrinkage, respectively. the only statistically significant difference found between gowns for dimensional stability was in the lengthwise direction after 75 ils between the brand b-l3 gown and the brand a-l2 (p = 0.03) and l3 (p = 0.006) gowns. laundering was found to significantly shrink the l3 gowns for both brands after 25, 50, and 75 ils compared to dimensions after 1 wash (p < 0.05). there were no significant differences for colorfastness to laundry between the gowns or after multiple wash cycles for the reusable gowns. of the reusable gowns, brand a-l2 was the least colorfast (p < 0.05) with an average rating of 2.75, and brand b-l2 was the most colorfast with an average rating of 4.3. eight parameters were chosen for assessment, and the average fabric hand results after 1 and 75 ils are provided in table 4 . differences in fabric hand between the disposable gowns were not statistically significant as there was little to no variance between raters, except for compressibility. significant differences between the reusable gowns were found for the following properties: flexibility, compressibility, resiliency, surface contour, surface friction, and thermal character. after 50 ils, the brand b gowns had significantly higher (p < 0.05) thermal character ratings than the brand a gowns, indicating they felt warmer. industrial laundering had no significant effect on the reusable gowns for any parameter of fabric hand. while all reusable gowns met minimum aami pb70 requirements for impact penetration and hydrostatic pressure water resistance, the disposable gowns in this study did not. for impact penetration, only the l3 disposable gown met aami requirements. this could be reflective of the l3 gown's fabric thickness and fabric weight, both of which are more than twice that of the l1 and l2 disposable gowns. fabric thickness and weight are known to be related to protection. results indicate the l1 and l2 disposable gowns in this study would increase the risk of liquid exposure for hcws, therefore reducing their safety. interestingly, the hydrostatic pressure test results, which reflect a more stringent assessment of water resistance under pressure, contradict those of impact penetration. all l2 and l3 disposable gowns met the minimum requirements for hydrostatic pressure (>20cm for l2; >50cm for l3). even so, the reusable gowns provided significantly higher water resistance, especially the reusable l3 gowns. both the impact penetration and hydrostatic pressure results support the adoption of reusable isolation and surgical gowns over their disposable counterparts in favor of higher water resistance protection at all levels. from a durability standpoint, the breaking, tear, and seam strength results support the adoption of multiple-use gowns. while statistically significant reductions in breaking, tear, and seam strength were found after 75 ils, the reusable gowns maintained superior strength that exceeded the minimum astm requirements, regardless of the number of industrial launderings. the disposable gowns, however, failed to meet the breaking strength requirements in the crossmachine direction and were close to failure in the same direction for tear strength. additional durability testing included pilling resistance, which supports similar conclusions to strength testing. overall durability findings indicate that all reusable gowns in this study, regardless of brand or protection level, maintained sufficient breaking, tear, and seam strength, as well as pilling resistance, across their typical wash life, providing superior durability compared to the disposable gowns. in addition to strength, reusable gowns should maintain their dimensions after multiple uses and launderings to ensure proper fit, which can impact protection, especially in the critical zone areas. although aami pb70, astm f3352, and astm f2407 do not include minimum performance requirements for dimensional change of medical gowns, typically, astm performance specifications for other types of garments include a 3% tolerance for shrinkage and/or growth after 5 home launderings 35, 36 . after 75 ils, all reusable gowns had a shrinkage percent below 3% except for the brand b-l3 gown. considering the referenced astm performance specifications are for consumer apparel items after only 5 consumer launderings, a shrinkage of only 3.6% after 75 ils should be sufficient for maintaining proper dimensions across the wash life of a reusable medical gown. comfort, or a lack thereof, is often a common complaint by end-users of reusable gowns due to poor breathability and permeability 3, 5, 14, 37 . thermal comfort is one of the top gown performance features that is likely to discourage hcw compliance with wearing appropriate ppe 3 . disposable gowns are known for being more "comfortable" and breathable, and therefore, often preferred by hcws, even though they provide lower levels of protection, as evidenced by the results in other areas of this study. interestingly, however, are previous studies that have demonstrated that in the short term, reusable gowns are preferred for wearer comfort; it is in the long duration surgical settings that disposable gowns become the preference of medical professionals 14, 38 . the air permeability of the reusable gowns in this study was virtually nonexistent. as reusable gowns provide greater protection than disposable gowns, in most cases, and are more economical and sustainable, innovative materials should be explored, which enhance the comfort of the wearer while still providing adequate liquid barrier protection. this would be a necessary improvement in order to increase the use and adoption of reusable gowns by hcws and medical professionals. in terms of appearance retention, there were no significant differences in colorfastness between the reusable gowns after 1 il. similarly, for fabric hand, significant differences between the reusable gowns after one wash were found only for surface friction and flexibility. after 75ils, there were minimal differences in a variety of fabric hand properties between reusable gown protection levels and brands. to the authors' knowledge, this is the first study of its kind to assess the performance of reusable gowns over their wash life. these findings support the durability of reusable gowns, making them more economical than disposable gowns and providing greater protection for hcws. this is especially important in times of ppe shortages, such as the current covid-19 pandemic, for which the cdc recommended the use of cloth gowns 9 . most importantly, industrial laundering had no detrimental effect on the water-resistance of the reusable gowns. the overall strength of the reusable gowns was also significantly higher than the disposable gowns and far surpassed the astm performance requirements at all wash intervals. the same was found for pilling resistance. further, the reusable gowns had superior colorfastness ratings and excellent dimensional stability after 75 ils. comfort is often the parameter that most deters medical professionals from selecting reusable gowns over disposables 14, 37 . laundering did not significantly affect or change the air permeability of the reusable gowns as there was practically none to begin with. improving thermal comfort while maintaining barrier protection may be the biggest hurdle for wider acceptance of multiple-use gowns by hcws. previous studies make the undeniable argument that reusable gowns are superior from an environmental perspective 12, 14 . this study aimed to assess this argument from a performance standpoint. overall findings determined that some disposable gowns on the market today are still not meeting aami pb70 performance requirements for hcw protection, even after the ebola crisis of 2014 brought this issue to light 11 . also, industrial laundering did not have a detrimental effect on the reusable gowns for any measured performance parameter. therefore, while previous studies have concluded that reusable medical gowns provide significant cost savings from an environmental standpoint, the findings of this study support their superior protection and performance. the largest drawback preventing greater adoption of reusable gowns is their lack of wearer comfort during longer duration surgical settings 14, 38 . limitations of this research include sample size, which was limited to one supplier per protection level for the disposable gowns and two suppliers per protection level for the reusable gowns. further, l4 gowns were not included in this study due to measurement equipment limitations. in addition, conditions of use and sterilization between laundering cycles could not be replicated or conducted within this study's scope. future studies should include all levels of aami gowns, and protection from bloodborne pathogens should be evaluated for both disposable and reusable gowns. reusable gowns should be evaluated for bloodborne pathogen penetration after multiple wash/dry cycles, including sterilization between each cycle. the representation of various material technologies available in both types of medical gowns should also be explored. future studies should expand the sample size, protection levels, and material variety to include greater representation of the overall medical gown market. liquid barrier performance and classification of protective apparel and drapes intended for use in health care facilities types of personal protective equipment used to combat covid-19 a review of isolation gowns in healthcare: fabric and gown properties single-use vs. reusable gowns and drapes microorganism protection. in: scott ra (ed) textiles for protection code of federal regulations title 21 subchapter h --medical guidance for the selection and use of personal protective equipment (ppe) in healthcare settings guideline for isolation precautions 60 minutes investigates medical gear sold during ebola crisis environmental considerations in the selection of isolation gowns: a life cycle assessment of reusable and disposable alternatives importance of lcas: now, in future a comparison of reusable and disposable perioperative textiles application of cost/benefit analysis for surgical gown and drape selection: a case study effect of laundering on the barrier properties of reusable surgical gown fabrics a sanitary study of commercial laundry practices killing of fabric-associated bacteria in hospital laundry by low temperature washing clarification of interpretive guidance at f-tag 441-laundry and infection certification/surveycertificationgeninfo/policy-and-memos-to-states-and-regions-items/survey-and-cert-letter-13-09 american association of textile chemists and colorists. tm42-2017e test method for water resistance: impact penetration american association of textile chemists and colorists american society for testing and materials. astm d3776 standard test methods for mass per unit area (weight) of fabric american society for testing and materials. astm d1777 standard test method for thickness of textile materials american society for testing and materials. astm d5034 standard test method for breaking strength and elongation of textile fabrics (grab test) american society for testing and materials. astm d5587 standard test method for tearing strength of fabrics by trapezoid procedure american society for testing and materials. astm d1683/d1683m standard test method for failure in sewn seams of woven apparel fabrics american society for testing and materials. astm d737 standard test method for air permeability of textile fabrics american association of textile chemists and colorists. aatcc evaluation procedure ep5 fabric hand: guidelines for the subjective evaluation of american association of textile chemists and colorists. aatcc evaluation procedure ep1 gray scale for color change american society for testing and materials. astm d4970 standard test method for pilling resistance and other related surface changes of textile fabrics: martindale tester american association of textile chemists and colorists. aatcc test method 96 dimensional changes in commercial laundering of woven and knitted fabrics except wool american society for testing and materials. astm f3352-19 standard specification for isolation gowns intended for use in healthcare facilities american society for testing and materials. astm f2407-06(13) standard specification for surgical gowns intended for use in healthcare facilities american society for testing and materials. astm d7020 standard performance specification for woven blouse, dress, dress shirt, & sport shirt fabrics american society for testing and materials. astm d4156 standard performance specification for women's and girls' knitted sportswear fabrics isolation gowns in health care settings: laboratory studies, regulations and standards, and potential barriers of gown selection and use reducing medical waste key: cord-351031-e8suoeim authors: liang en ian, wee; sim, xiang ying jean; conceicao, edwin philip; aung, may kyawt; tan, kwee yuen; ko, kwan ki karrie; wong, hei man; wijaya, limin; tan, ban hock; venkatachalam, indumathi; ling, moi lin title: containing covid-19 outside the isolation ward: the impact of an infection control bundle on environmental contamination and transmission in a cohorted general ward date: 2020-06-26 journal: am j infect control doi: 10.1016/j.ajic.2020.06.188 sha: doc_id: 351031 cord_uid: e8suoeim background: during an ongoing outbreak of covid-19, unsuspected cases may be housed outside of dedicated isolation wards. aim: at a singaporean tertiary hospital, individuals with clinical syndromes compatible with covid-19 but no epidemiologic risk were placed in cohorted general wards for covid-19 testing. to mitigate risk, an infection control bundle was implemented comprising infrastructural enhancements, improved personal-protective-equipment (ppe), and social distancing. we assessed the impact on environmental contamination and transmission. method: upon detection of a case of covid-19 in the dedicated general ward, patients and healthcare workers (hcws) contacts were identified. all patient and staff-close contacts were placed on 14-day phone surveillance and followed-up for 28 days; symptomatic contacts were tested. environmental samples were also obtained. findings: over a 3-month period, 28 unsuspected cases of covid-19 were contained in the dedicated general ward. in 5 of the 28 cases, sampling of the patient's environment yielded sars-cov-2; index cases who required supplemental oxygen had higher odds of environmental contamination (p=0.01). a total of 253 staff close-contacts and 45 patient close-contacts were identified; only 3 hcws (1.2%, 3/253) required quarantine. on 28-day follow-up, no patient-to-hcw transmission was documented; only one symptomatic patient close-contact tested positive. conclusion: our institution successfully implemented an intervention bundle to mitigate covid-19 transmission in a multi-bedded cohorted general ward setting. during an ongoing outbreak of covid-19, unsuspected cases may be housed outside of dedicated isolation wards. at a singaporean tertiary hospital, individuals with clinical syndromes compatible with covid-19 but no epidemiologic risk were placed in cohorted general wards for covid-19 testing. to mitigate risk, an infection control bundle was implemented comprising infrastructural enhancements, improved personalprotective-equipment (ppe), and social distancing. we assessed the impact on environmental contamination and transmission. upon detection of a case of covid-19 in the dedicated general ward, patients and healthcare workers (hcws) contacts were identified. all patient and staff-close contacts were placed on 14-day phone surveillance and followed-up for 28 days; symptomatic contacts were tested. environmental samples were also obtained. over a 3-month period, 28 unsuspected cases of covid-19 were contained in the dedicated general ward. in 5 of the 28 cases, sampling of the patient's environment yielded sars-cov-2; index cases who required supplemental oxygen had higher odds of environmental contamination (p=0.01). a total of 253 staff closecontacts and 45 patient close-contacts were identified; only 3 hcws (1.2%, 3/253) required quarantine. on in the current covid-19 pandemic, healthcare-associated transmission has been a major concern, with almost one-third of patients comprising healthcare workers (hcws) and hospitalised inpatients. 1 to reduce healthcare-associated spread, standard recommendation is that single-person rooms with dedicated toilets be used to isolate suspected covid-19 cases, and negative-pressure airborne-infection-isolation-rooms (aiir) be used for cases in which aerosol-generating procedures (agps) may be required. 2 however, during an outbreak of covid-19 with ongoing local transmission, distinguishing covid-19 from ordinary viral respiratory tract infection becomes challenging, as the symptoms of covid-19 are non-specific. 3 admitting all patients with acute respiratory disease (ard) into dedicated isolation wards (iw) during a covid-19 outbreak poses a logistical challenge, especially in hospitals with limited resources. cases of covid-19 may thus be housed outside the iw prior to detection; with potential for onward spread. delayed detection of cases of covid-19 can result in the inadvertent unprotected exposure of significant numbers of hcws and patients, leading to the quarantine of large numbers of hcws 4 and lockdown of wards. 5 furthermore, healthcare-associated outbreaks of covid-19 have been linked to infected patients in the general ward setting in whom covid-19 was unsuspected; with devastating consequences for hcws and patients. [6] [7] [8] during ongoing community transmission of covid-19, infection control strategies for the general ward setting are required in order to mitigate the potential of healthcare-associated transmission from unsuspected cases of covid-19. in singapore, a globalised asian city-state, local transmission of covid-19 has been ongoing since early february 2020. 9 our institution's iw was reserved for cases meeting official criteria for confirmed/suspected covid-19. however, rising numbers of locally-transmitted cases meant that all patients presenting with ard, even without suspicious contact or travel history, were potentially at-risk of having unsuspected covid-19 infection. after documentation of local community transmission, in order to mitigate the potential for healthcare-associated transmission from undetected cases of covid-19, our institution placed individuals with clinical syndromes compatible with covid-19 (eg. ard, or undifferentiated viral fever) who did not have epidemiologic risk (eg. no history of contact with covid-19 cases or clusters) in dedicated general wards segregated from the rest of the hospital. these general wards comprised a mixture of single rooms and cohorted cubicles with shared toilets. in these general wards, termed as respiratory surveillance wards (rsws), an infection control bundle was implemented comprising infrastructural enhancements, improved personal-protective-equipment (ppe), and social distancing between patients, in order to mitigate the risk of a potential covid-19 case initially admitted outside of an aiir. we examined the impact of an infection control bundle on environmental contamination and transmission in a cohorted general ward setting, when unsuspected cases of covid-19 were detected, focusing on the impact of such a strategy in mitigating healthcare-associated transmission. singapore general hospital (sgh) is the largest public acute tertiary care hospital in singapore, with 1785 beds. over a 3-month period from 7 th february to 7 th may 2020, we evaluated our institution's experience with managing unsuspected covid-19 infection in cohorted rsws, using a cross-sectional study design. on 5th february 2020, immediately after the first reported case of local transmission, 9 our institution adopted a containment strategy to place individuals without epidemiologic risk, but who presented with clinical syndromes compatible with covid-19 (eg. ard, or undifferentiated viral fever) in the rsws for enhanced surveillance. patients could only be transferred out of the rsw if oropharyngeal swabs for sars-cov-2 pcr were negative on 2 consecutive occasions, done 24 hours apart. 10, 11 high-risk suspect patients fulfilling official criteria for suspected covid-19 (based on suspicious epidemiology or travel history) were admitted to the iw instead. while high-risk covid-19 suspects were housed in aiirs in the iw (singleoccupancy rooms with ≥ 12 air changes-per-hour, controlled direction of air flow with negative differential pressure more negative than -2.5 pascal, and anterooms designed to provide an "air-lock" between the adjacent area and the aiir), the rsw was a modified normal-pressure general ward containing a mixture of normal-pressure single rooms and cohorted cubicles. single rooms had their own attached toilet, whereas cohorted cubicles utilised a shared toilet. each cohorted cubicle and single room had its own ventilation system, and air was not recirculated between cubicles or rooms. in the rsw, an infection control bundle was implemented comprising infrastructural enhancements, improved ppe, and social distancing between patients. infrastructural enhancements involved the reduction of bed density in cohorted cubicles and improved distancing between beds, with the construction of partitions between beds. in the cohorted cubicles of the rsw, the average number of beds was reduced to 3 beds per cubicle, to ensure that beds were spaced at least 2 metres apart; as compared to an average of 5-6 patients per cohorted cubicle in the typical general ward. 12 primary physicians in the rsw prioritised patients who required supplemental oxygen, non-invasive ventilation, or clinical features suspicious of viral pneumonia (eg. normal procalcitonin, lymphopenia) for admission to single rooms, though this was not always feasible due to the large number of admissions. within the rsws, cleaning and disinfection with 1000 ppm sodium hypochlorite were stepped up, with the wards and toilets being cleaned 3 times a day. a riskstratified approach was adopted with regards to ppe. initially, hcws in these wards used n95 respirators as ppe during routine care, with full ppe (n95 respirators, eye protection, gown and gloves) reserved for instances where agps needed to be performed. however, from mid-march 2020, given the rising number of covid-19 case being picked up in the rsw, hcws used full ppe when caring for these patients. compliance with usage of ppe in the rsw was audited by infection control nurses from the department of infection prevention and epidemiology (ipe). finally, social distancing was encouraged within the rsw. 12 patients were advised to wear surgical masks, to remain within their room or cohorted cubicle at all times and avoid mingling with each other (if they were housed in a cohort cubicle). surgical masks were provided for all patients, and patients were advised to only remove their masks during meals. partitions between patient beds also minimised mingling. there was a strict no-visitors rule while patients were warded in the rsw. upon detection of a confirmed case of covid-19 in the rsw, the affected room or cohorted cubicle was temporarily locked down i.e. no new admissions to and no transfers out of the cubicle. both the confirmed case, as well as patient close-contacts, were transferred to the iw. patient close-contacts were defined as a patient who had stayed in the same cohort cubicle with the index case; 5 given potential contamination of the shared air and surface environment from droplet and fomite spread. 13 simultaneously, contact tracing was done to identify hcws who had come into contact with the confirmed case, and risk stratification was done based on the duration of contact, nature of activity (eg. agps), and type of ppe worn at the time of contact. staff close-contacts were defined as hcws who had contact within two metres of the index case for a cumulative time of ≥15 minutes, or who had performed agps without appropriate ppe. appropriate ppe was defined as at least an n95 mask for routine care and full ppe for agps. all patient close-contacts and staff close-contacts were monitored via phone surveillance for symptoms such as cough, dyspnoea and myalgia, and twice-daily temperature measurements, over a 14-day period from the date of exposure. if patient close-contacts or staff close-contacts developed symptoms, respiratory specimens were obtained, and swabs sent for covid-19 testing. it was standard protocol to repeat the covid-19 test 24 hours apart from the first in symptomatic close-contacts, if the first test was negative. all patient close-contacts and staff closecontacts were followed up for a 28-day period from the date of exposure, to determine if they tested positive for covid-19 within this window; however, testing was only performed if contacts became symptomatic. all patient close-contacts, as well as staff close-contacts who had not utilised appropriate ppe, were placed under a 14-day quarantine based on our local ministry of health (moh)'s guidelines. patient close-contacts who had unresolved medical issues served out the full duration of their quarantine period in the isolation ward, even if they may have had a negative covid-19 test during the quarantine period, whereas patient close-contacts who were medically fit for discharge were discharged to serve out their quarantine at home. upon detection of a confirmed case of covid-19 in the rsw, environmental sampling was done in the rooms to test for sars-cov-2 prior to terminal cleaning with sodium hypochlorite 1000 ppm. per protocol, 13 areas that were sampled routinely included: high-touch areas in the patient's immediate vicinity, including the patient's call bell, foot and cotside of the bed, and bedside table; as well as toilet facilities, namely the toilet bowl as well as the bathroom drain. staff wearing full ppe used sterile pre-moistened swab sticks to swab high-touch areas for 2-3 minutes over a large surface. repeat swabs were done post-terminal cleaning, using the same procedure. investigation for sars-cov-2 rna was done by qualitative real-time reverse transcription pcr (rrt-pcr) targeting e gene and orf1b-nsp14 14,15 on respiratory tract samples and environmental surveillance samples. as this was a descriptive study based on data collected by the hospital's ipe department as part of an outbreak investigation, ethics approval was not required under our hospital's institutional review board guidelines; and application for waiver was formally obtained (cirb 2020/2369). over the study period, a total of 4621 patients were admitted to the rsw, of which 28 were confirmed cases of covid-19 (0.61%, 28/4621). over the same period, a total of 845 cases of covid-19 were picked up amongst the 2681 patients admitted to the iw (31.5%, 845/2681). our institution used a broader set of case criteria for identifying suspect cases of covid-19 compared to the official criteria, accounting for the higher pickup in iw. 16 the rsw accounted for 3.2% (28/873) of covid-19 cases admitted to our institution. only one case of covid-19 was initially admitted to the general ward instead of the rsw/iw during the 3-month study period, due to mild respiratory symptoms which were not apparent on initial triage in the emergency department. 12 the details of covid-19 patients detected in the rsw, as well as the numbers of patient and staff closecontacts, are provided in table 1 no staff close-contacts went on to develop covid-19 post-exposure despite intensive surveillance. however, amongst the 45 exposed patients, a total of 24 patients developed symptoms within the 14-day observation period while on phone surveillance and were subsequently tested for covid-19. only one patient close-contact who developed symptoms subsequently tested positive (2.2%, 1/45). although the alternative possibility that this particular patient could have been exposed to an asymptomatic contact just prior to admission and was still within the incubation period 17 at the point of admission could not be fully excluded, detailed epidemiological investigations were conducted for this case (figure 2) . of note, the index case (case #2) had the longest duration of stay in the rsw, at 49.5 hours. the patient close-contact that subsequently developed covid-19 was an elderly male with a past medical history of chronic obstructive pulmonary disease (copd). he had been admitted to another hospital 12 days prior to the current admission; during the previous admission, covid-19 testing was negative. he shared a cohorted cubicle with case #2 for 17 hours and had been discharged prior to the confirmation of covid-19 in case #2. during his admission, he had 2 negative swabs for sars-cov-2, 24 hours apart. he was placed on home quarantine, but subsequently developed symptoms 5 days post-exposure and tests were positive for sars-cov-2 on re-admission. environmental sampling of high-touch areas in the shared common areas prior to cleaning was negative for sars-cov-2. of the two other exposed patients, one was bedbound and nonconversant, while the other was ambulatory. staff had previously observed social mingling between the ambulatory patients in the cubicle, without wearing surgical masks. while the duration of overlap for the exposed patient that subsequently developed covid-19 was the shortest, it also corresponded with the period during which the index patient was still well and able to interact socially. the index patient deteriorated subsequently over the course of the day and 4 hours after transfer to iw in the evening, required intubation and mechanical ventilation for respiratory failure. he eventually demised at day 30 of admission; respiratory samples prior to demise remained positive for sars-cov-2. the main finding of our study was that an infection control bundle comprising infrastructural enhancements, improved ppe and social distancing mitigated the risk of environmental contamination and transmission in a cohorted general ward setting. in our institution, the concept of a designated rsw for patients with clinical syndromes that were compatible with covid-19 ensured that the large majority of covid-19 cases diagnosed outside of the iw were still managed in areas where appropriate ppe, infrastructural enhancements and proper infection prevention practices (hand hygiene, environment and equipment hygiene) were in place to reduce healthcare-associated spread. via early testing and detection, the duration of exposure in the cohorted rsw was kept relatively short (~15 hours on average), compared to the median duration of viral shedding over the clinical course. 18 additionally, as peak viral shedding is thought to occur earlier in the clinical course during the first week of symptoms, early detection can potentially mitigate transmission risk during peak infectivity. 18 early detection in the clinical course prior to deterioration also helped to minimise the number of agps performed outside of the iw setting. indeed, although almost one-fifth of the index cases subsequently deteriorated and required intubation, this occurred after the patients had been already transferred into the iw. this was important given the increased potential of healthcare-associated transmission during aerosolization caused by agps. for instance, delayed detection in a single patient that required intubation and mechanical ventilation prior to the diagnosis of covid-19 pneumonia resulted in the quarantine of 41 hcws for 2 weeks, due to a prolonged duration in the general ward prior to detection 4 in the cluster of covid-19 cases reported in this study, there were several risk factors: the duration of the index patient's stay in the rsw was the longest (>48 hours) and staff had previously observed social mingling between the unmasked patients in the cubicle. though healthcare-associated transmission could not be definitively proven, these findings reinforce the importance of a bundle of interventions in reducing risk of covid-19 transmission: social distancing in high-risk areas, early detection to minimise exposure duration; and usage of appropriate ppe in higher-risk areas to minimise hcw exposure. a short duration of stay in the dedicated general ward, reduction of the number of beds in cohorted cubicles, and usage of full ppe minimised the total numbers of patient and hcw exposures. indeed, although a total of 28 hitherto unsuspected cases of covid-19 were picked up in the rsw, there were only 45 patient closecontacts. in comparison, delayed detection of a single case of covid-19 in the setting of a multi-bedded cohorted general ward resulted in the exposure of as many as 71 patients, with all occupants of a cohort cubicle deemed to be in close contact and requiring quarantine. 5 in our institution itself, a single case of covid-19 in the non-modified general ward resulted in the potential exposure of 18 patients. 12 as patient close contacts require quarantine in suitable isolation facilities within hospital if medically unfit for discharge, 5 minimising the number of patient close contacts is crucial in relieving additional strain on hospital resources during an ongoing outbreak. persistence of sars-cov-2 in the environment, in aerosols and on surfaces, 19,20 provides a potential vector for transmission. multiple studies report extensive environmental contamination of inanimate surfaces in the immediate environment of covid-19 cases (patients' rooms and toilets) prior to cleaning. 13.21 however, the bulk of these studies are conducted in aiirs; the applicability of these studies to the general ward setting may potentially be confounded by differences in ventilation, airflow and room layout (such as the presence of anterooms to segregate the patient's immediate environment from common areas). 22 a small study that tested environmental samples from 2 cohorted 4-bed cubicles on a general ward detected sars-cov-2 in 13.6% of samples collected, generally from near-patient environments; however, the covid-19 patients placed in these cohorted cubicles were no longer symptomatic at the point of sampling. 23 uniquely, our study provided the opportunity to investigate the extent of environmental contamination in covid-19 patients housed in a general ward setting, early on at the point of initial admission; although this was modified by the effects of our infection control bundle. the rate of environmental contamination reported in our study was low; less than 5% of environmental samples tested positive, compared to other studies which reported rates of 15-50%, mainly from aiirs. [21] [22] [23] [24] [25] this could potentially be attributed to the effect of the infection control bundle comprising infrastructural enhancements and social distancing that was introduced in our designated wards; though the precise contribution of each component of the bundle could not be assessed. notably, though, in our study the majority of positive environmental surveillance samples came from patients who were on supplemental oxygen in the rsw. this may be related to increased risk of droplet dispersion in patients on supplemental oxygen 26, 27 or the inability to comply with mandatory usage of face masks. 28 our study had several limitations. only patient and hcw contacts with fever or respiratory symptoms were tested with rt-pcr, hence the possibility of asymptomatic infection among the exposed patients and hcws cannot be entirely excluded. as the diagnostic yield of pcr testing for sars-cov-2 is likely dependent on the quality of sampling, 29 cases may have been missed due to sampling issues; however, all symptomatic close-contacts were tested at least twice, 24 hours apart. the follow-up of potentially exposed patients and hcws to test for seroconversion, when such tests are developed, would be useful. for environmental sampling, we were unable to perform viral culture; hence the viability of the virus found from environmental samples could not be ascertained. we were also unable to perform air sampling for index cases, as upon confirmation of covid-19, cases were immediately moved to the iw to reduce risk of transmission. in conclusion, over a 3-month period, our institution implemented a bundle of interventions to reduce risk of intra-hospital transmission of covid-19 in a multi-bedded cohorted general ward setting, through the implementation of an infection control bundle comprising infrastructural enhancements, improved ppe, and social distancing between patients. routine testing for patients presenting with clinical syndromes compatible with covid-19 allowed for early detection and early isolation, reducing the duration of exposure in the general ward setting and further mitigating the risk of healthcare-associated transmission. clinical features of patients infected with 2019 novel coronavirus in wuhan, china centres for disease control and prevention, usa. interim infection prevention and control recommendations for patients with suspected or confirmed coronavirus disease 2019 (covid-19) in healthcare settings clinical characteristics of coronavirus disease 2019 in china covid-19 and the risk to healthcare workers: a case report risk of nosocomial transmission of coronavirus disease 2019: an experience in a general ward setting in journal of hospital infection covid-19 in a long-term care facility -king county clinical and transmission characteristics of covid-19 -a retrospective study of 25 cases from a single thoracic surgery department fast nosocomial spread of sars-cov2 in a french geriatric unit. infection control & hospital epidemiology covid-19 in singapore-current experience: critical global issues that require attention and action respiratory surveillance wards as a strategy to reduce nosocomial transmission of covid-19 through early detection: the experience of a tertiary-care hospital in singapore deisolating covid-19 suspect cases: a continuing challenge minimising intra-hospital transmission of covid-19: the role of social distancing air, surface environmental, and personal protective equipment contamination by severe acute respiratory syndrome coronavirus 2 (sars-cov-2) from a symptomatic patient detection of 2019 novel coronavirus (2019-ncov) by real-time rt-pcr molecular diagnosis of a novel coronavirus (2019-ncov) causing an outbreak of pneumonia containing covid-19 in the emergency room: the role of improved case detection and segregation of suspect cases the incubation period of coronavirus disease 2019 (covid-19) from publicly reported confirmed cases: estimation and application virological assessment of hospitalized patients with covid-2019 aerosol and surface stability of sars-cov-2 as compared with sars-cov-1 persistence of coronaviruses on inanimate surfaces and their inactivation with biocidal agents environment and personal protective equipment tests for sars-cov-2 in the isolation room of an infant with infection lack of sars-cov-2 rna environmental contamination in a tertiary referral hospital for infectious diseases in northern italy environmental contamination of sars-cov-2 during the covid-19 outbreak in south korea environmental contamination by sars-cov-2 in a designated hospital for coronavirus disease 2019 detection of air and surface contamination by sars-cov-2 in hospital rooms of infected patients evaluation of droplet dispersion during non-invasive ventilation, oxygen therapy, nebuliser treatment and chest physiotherapy in clinical practice: implications for management of pandemic influenza and other airborne infections aerosol dispersion during various respiratory therapies: a risk assessment model of nosocomial infection to health care workers covid-19: face masks and human-to-human transmission. influenza other respir viruses mers coronavirus: diagnostics, epidemiology and transmission covid19 key: cord-332815-1w1ikj7q authors: zhan, mingkun; anders, robert l.; lin, bihua; zhang, min; chen, xiaosong title: lesson learned from china regarding use of personal protective equipment date: 2020-08-11 journal: am j infect control doi: 10.1016/j.ajic.2020.08.007 sha: doc_id: 332815 cord_uid: 1w1ikj7q background: in wuhan, china, in december 2019, the novel coronavirus was detected. the virus causing covid-19 was related to a coronavirus named severe acute respiratory syndrome coronavirus (sars-cov). the virus caused an epidemic in china and was quickly contained in 2003. although coming from the same family of viruses and sharing certain transmissibility factors, the local health institutions in china had no experience with this new virus, subsequently named sars-cov-2. methods: based on their prior experience with the 2003 sars epidemic, health authorities in china recognized the need for personal protective equipment (ppe). existing ppe and protocols were limited and reflected early experience with sars; however, as additional ppe supplies became available, designated covid-19 hospitals in hubei province adopted the world health organization guidelines for ebola to create a protocol specific for treating patients with covid-19. results: this article describes the ppe and protocol for its safe and effective deployment and the implementation of designated hospital units for covid-19 patients. to date, only two nurses working in china who contracted sars-cov-2 have died from covid-19 in the early period of the epidemic (february 11 and 14, 2020). conclusion: the lessons learned by health care workers in china are shared in the hope of preventing future occupational exposure. in december 2019, a hospital in wuhan, hubei province, reported several cases of severe unexplained viral pneumonia. the outbreak appeared just before the spring festival, one of china's most significant holidays. millions of people traveled during the holiday. the government scrambled to determine the etiology of the disease. the first patients began seeking medical care with symptoms of respiratory distress, headaches, and fever. initially, the diagnosis was an upper respiratory infection and treated with standard therapy for influenza-like illness. as the number of infected patients continued to increase rapidly, and the treatments administered did not seem to improve patients' conditions, further investigations were necessary. there were approximately 110,000 health care workers (hcws) in wuhan, which could be called upon to provide care for this emerging epidemic. quickly the healthcare facilities became overwhelmed with patients. as a result of working long hours under very stressful conditions, there were reported deaths of hcws. throughout the epidemic, 42,600 travel nurses and physicians came into hubei province, primarily to wuhan from throughout china to provide relief to the wuhan hcws. 1 the paper focuses primarily on the use of ppe to help prevent transmission of severe acute respiratory syndrome coronavirus 2 (sars-cov-2) to hcws. the aim is to provide more detail regarding level-3 protection protocols used at designated covid-19 hospitals in hubei province to prevent the spread of the virus to hcws. the methods to protect hcws, designated as level-3 protection in china, included a personal protection protocol for proper use of ppe with coveralls and procedures for changes to the flow of patients and personnel through the designated covid-19 hospitals. 3 during the ebola outbreak, the world health organization (who) had recommended extensive guidance on the protection of hcws. 4 biosafety level-3 protection is well known in laboratories that handle dangerous and potentially lethal microbes transmitted by droplets or aerosols. there are many similarities between the recommendations for the protection of laboratory workers and the who recommendations for ppe to protect bedside care providers from filovirus disease. after comparing the existing recommendations, all designated covid-19 hospitals adopted the recommendations endorsed by the who for filovirus disease (ebola). the recommendation ensures protection from head to toe using the coveralls (not the gown), thus minimizing any areas of skin exposure, in combination with the lockdown of designated covid hospitals. 4 hospital units treating covid-19 patients were locked, meaning only personnel wearing the proper protective equipment were allowed entry, and non-covid-19 patients were not admitted. most of these units did not have a negative pressure system. air disinfectant machines that operated 24-hours per day were used in the isolation units and in the transition unit (where removal of the ppe occurred). upon arrival at the hospital, nursing and physician staff entered the clean areas through a staff-dedicated hallway; patients arrived through another patient-dedicated entrance. additionally, there were separate elevators for staff and patients. the temperature of hcws was measured on entrance. hcws with a temperature of more than 37.2 ℃ (99 °f) were not allowed to enter the hallway. in the clean areas, staff would begin following a standardized procedure for donning ppe. the who ebola ppe protocol includes a first layer of a scrub suit, followed by rubber boots (which were too cumbersome for work in the isolation unit) or closed-toe shoes with shoe covers, two layers of gloves, coverall, face mask, face shield/goggles, a head and neck covering, a surgical bonnet covering the neck and sides of the head or a hood, and a disposable waterproof apron. 5 the adopted covid-19 protocol included a hospital-provided scrub suit, complete covering of dorsum of the foot and ankles with socks covered by plastic wrap and closed shoes with two layers of boot covers (substituted for the heavy rubber boots), three layers of gloves, a coverall, n95 face mask, surgical mask, face shield/goggles, hood with two layers of head covering, and a disposable waterproof surgical gown. the rubber boots were available for staff to wear from the transition unit to home or hotel. before starting the 4-hour shift (primarily for nurses) and a 6-hour shift (physicians), the staff arrived in the clean areas where a one-way hall led to the locked isolation unit. most of medical and nursing staff wore diapers instead of leaving the unit to use the bathroom. there are various approaches to donning and removing the ppe; posters developed by the who were available to staff for reference. 5 using 0.5% w/v isopropyl alcohol 75% v/v is the first step in performing hand hygiene. a total of 17 steps were involved in donning the ppe as described in the adopted protocol above. at the end of a four-or six-hours shift, staff moved to a transition unit, located outside of the locked isolation unit where the ppe removal and decontamination process began. the removal of ppe is a time with a high risk of contamination. the process started with washing the gloved hands with a solution of isopropyl alcohol; hand sanitizing is also recommended after the removal of each piece of ppe. when taking off the surgical gown and coveralls, ensure the front is folded inward to minimize the possibility of contamination. it is recommended the gloves be removed during this step and turned inward as well. all contaminated ppe must be disposed of properly. after removal of the n95 mask, it is recommended a surgical facemask be worn. after removal of the ppe, the staff then proceeds to the clean unit. the steps in table 1 are our recommendations for additional decontamination. the who protocol is silent on the steps to be taken after the ppe is removed. each agency needs to adapt the process to meet their goals for staff safety. table 1 illustrates only one method, which was the method used in covid-19 facilities in hubei province.  shower and change to clean clothes and rubber boots.  arrive at hotel/home, clean boots with disinfectant and remove them (leave them at the designated area in the lobby of the hotel), and change to slippers.  remove and leave the jacket provided by the hospital at the designated area of the hotel lobby and change to the coat (the coat was sprayed with chlorine disinfectant every 4 hours).  leave slippers outside of the individual room or home and change to house slippers.  perform hand hygiene with a solution of isopropyl alcohol, then remove the coat and leave in the area near the door to the room or home.  take a full-body bath with soap and move to a clean area of the room to change to a different pair of slippers.  clean the nasal cavity and ear canal with an alcohol swab.  use mouth wash before eating. in wuhan, the entire process of transiting from the hotel (for travel nurses and physicians), donning ppe, working their shift, removing the ppe, and returning home could take up to ten hours. thus, the staff had extensive time spent in preparing, providing care, or decontaminating before going home. isolation was encouraged to continue at the hotel or home to protect others from potential infection. as early as january 23, 2020, a total of 176 members of the hcws were clinically or laboratory diagnosed with covid-19. 6 since that time, with the implementation of the level-3 protection protocols and the implementation of covid-designated hospitals, the number of hcws diagnosed with covid-19 has decreased. 6 according to the chinese red cross foundation (crcf), as of june 2, 2020, a total of 3,623 hcws have been diagnosed with laboratory-confirmed or clinically confirmed covid-19 throughout mainland china. a total of 31 hcws had died from covid-19. 6 only two nurses were infected with sars-cov-2 while performing their duties and then died from covid-19. 7, 8 no other deaths from covid-19 of nurses who had worked in mainland china during the epidemic have been reported. in the usa as of april 9, 2020, there were 9,282 hcw with covid-19 and of these 73% were women. 9 investigators noted that the number of cases among hcws in the study were likely an underestimation as healthcare status was missing for 84% of patients reported nationwide. as of april 8, 2020, who had been recording 22,073 cases of covid-19 among hcws from 52 countries. nevertheless, there is currently no formal documentation of hcws covid-19 infections to the who. the true number of covid-19 hcws infections worldwide are potentially underrepresented. 10 liu and colleagues in a cross-sectional study of four hospitals in wuhan, china found that of 420 travel hcws caring for covid-19, none were infected with sars-cov-2. 11 the authors concluded the use of effective ppe is contributed to there being no infections among those hcws. their findings are consistent with the support recommendations in this study. the experience in designated covid-19 hospitals demonstrates the evolution of how hcws reacted to covid-19 in wuhan and hubei province. the lack of adequate ppe was a contributor to the number of hcws initially infected with sars-cov-2. many asymptomatic patients were seen for non-covid-related conditions unknowingly exposed to some hcws in the outpatient clinics, which also contributed to the infection rate. the ppe protocols implemented in designated covid-19 hospitals is thought to have approximately 90% of the 28,600 travel nurses were under age 40, and 25,300 travel nurses were women. 12 the nurses, for the most part, did not have underlying medical issues that might place them at risk. 10 younger age and gender has proven in some way to be protective. 13, 14 a cochrane systematic review of ppe supports the importance of putting on the ppe correctly, that it may be uncomfortable to wear, and there is a risk of contamination with removing it. 15, 16 before implementing the ppe protocols, nurses may have placed a greater emphasis on washing their hands, using gloves, and wearing a face mask and hair covering more frequently than other hcws (m. zhan, and b. lin, personal communication may 2, 2020). however, the rapid adoption of a level-3 protection and careful use of ppe including coveralls was most likely a significant factor in protecting the nurses and other hcws from infection. (see table 2 ) 6 most of the early infections occurred before the adoption of level-3 protection. the report provides useful insight for developing future strategies to deal with infectious disease pandemics. the need for continued preparedness is paramount. policymakers must assume that there will be another epidemic. it may be the sars-cov-2 reemerging in the fall of 2020 or perhaps another viral agent. public health officials working in collaboration with federal, state, and local health departments must plan for the next epidemic. there needs to be a federal (national) and provisional (state) stockpile of ppe including coveralls and other necessary supplies required to care for patients with infectious diseases. there needs to be a method of ensuring that supplies are kept secure, and as they become outdated are rotated with new ones. the need for planning and funding for such including the necessary equipment and supplies is critical. failure to plan may mean additional lives lost. other hospital units beyond the ones used in this pandemic also need to be identified. providing the current rate of infection has dramatically declined. the environmental controls limiting social contact and mobility have helped to create a safer environment. readily available testing for suspected individuals with covid-19 has helped to identify those who may be at risk quickly. as a result of the level-3 protection protocols combined with admitting patients to only covid-19 designated hospitals, the number of hcws infected declined significantly since mid-february 2020. our experience may help other health systems better cope with outbreaks of the highly contagious sars-cov-2. transcript of the press conference of the information office of the state council on response to social concerns on hot topics such as alleviating the current shortage of medical supplies in china (in chinese) national health commission of the people's republic of china. technical guidelines on prevention and control of novel coronavirus infection in medical institutions world health organization. personal protective equipment for use in a filovirus disease outbreak-rapid advice guideline world health organization. how to put on and how to remove personal protective equipment -posters public announcement (in chinese) public announcement (in chinese) public announcement (in chinese) characteristics of health care personnel with covid-19 -united states use of personal protective equipment against coronavirus disease 2019 by healthcare professionals in wuhan, china: cross sectional study sex-and gender-specific observations and implications for covid-19. the western journal of emergency personal protective equipment for preventing highly infectious diseases due to exposure to contaminated body fluids in healthcare staff national health commission of the people's republic of china. transcript of the press conference of the information office of the state council on death from covid-19 of 23 health care workers in china apple and google build smartphone tool to track covid-19. npr new we want to acknowledge all state, local, and territorial health departments and personnel in china, working in and supporting the designated covid-19 hospitals in china. a special thanks to charon a. pierson, ph.d., gnp, faan, faanp, editor emeritus, journal of the american association of nurse practitioners for her medical editing support. key: cord-342523-52t7dh4n authors: dibner, julia j. title: direct covid-19 infection of enterocytes: the role of hypochlorhydria date: 2020-08-11 journal: am j infect control doi: 10.1016/j.ajic.2020.08.002 sha: doc_id: 342523 cord_uid: 52t7dh4n covd-19 disease is characteristically respiratory in nature; however, some patients have gastrointestinal symptoms. these include changes in taste, nausea/vomiting, abdominal pain, and diarrhea. a report has been published of a young patient who repeatedly tested positive in stool samples while nasopharyngeal tests remained negative. this raises doubts about our understanding of the dynamics of covid-19 disease. the current report describes a need for selective stool testing to explore fecal shedding of viral rna and presents a hypothesis for direct infection of enterocytes in cases of hypochlorhydria. diarrhea and changes in taste are among the most prevalent gastrointestinal (gi) symptoms of covid-19 disease and can occur in nearly 50% of patients (1, 2) . clinical and virological aspects of enteric covid-19 disease have been reviewed, with authors suggesting the need for study of possible fecal-oral transmission (1, 3) . such studies are justified by observed gi symptoms and detection of positive stool samples. in children, initial gi symptoms may be mild and transient (4) , but a case has been reported of positive fecal tests occurring in the absence of positive nasopharyngeal tests or respiratory symptoms (5) . the purposes of this brief report are to emphasize the importance of testing stool samples under certain conditions and to suggest a novel route of direct enterocyte infection by covid-19 in cases of developmental or acquired hypochlorhydria. 4 many defenses exist in the upper parts of the gi system to protect against infection by ingested pathogens. the low ph (1.5-3.0) of gastric acid is a particularly important one. in cases of hypochlorhydria (low stomach acid), the gastric environmental ph is raised to ph 3-5. for this reason, hypochlorhydria is associated with an increased risk for enteric infection (6, 7) . a large proportion of the human population suffers from hypochlorhydria. for example, gastric acid secretion is often depressed in the elderly (6), a high-risk population for contracting covid-19 disease. acquired h. pylori infection and the use of proton pump inhibitors (ppi) are also associated with low stomach acid (7), as is stress (8). covid-19 virus may not survive normal gastric acid ph levels of 1.5-3, but there is evidence that it can survive a ph level of 3 or above (9) . if covid-19 virus can resist the ph levels of 3-5 typical of hypochlorhydria, it would have a route from mouth to intestine, where the virus could directly infect ace2-bearing enterocytes there (1). although there is observational evidence that long-term or high-level use of ppi is associated with an increased risk of testing positive for covid-19 (10), certain histamine-2 receptor antagonists (h2ra) and a ppi have been observed to improve disease outcome in patients already infected with covid-19 virus (11) . this improvement in disease outcome is reportedly due to negative effects of the drugs on viral replication or on viral enzyme activity (11) . thus, roles of both ppi and h2ra in covid-19 disease merit further study. to date, covid-19 transmission through ingestion of contaminated food is not considered a concern. however, the route of virus delivery that results in gi symptoms and fecal 5 shedding might still be oral. the fact that changes in taste can be an early symptom of covid-19 infection (2) suggests that the virus does enter and infect the mouth. during exercise, occupational exertion, eating, drinking, or vocalizing, the mouth could be the recipient of infected droplets or aerosols. thus, oral delivery of virus may occur, particularly in those not wearing masks at the time of exposure. in fecal-oral transmission, the organism initially enters the body through the mouth. for covid-19, evidence that the gut is infected directly, and not secondarily to respiratory infection, is provided by negative nasopharyngeal tests in the presence of positive fecal samples collected simultaneously (5) . escape through the compromised gastric acid defense system of hypochlorhydria could give covid-19 virus access to intestinal enterocytes. hypothetically, the initial infection of an individual could occur there. covid-19 viral rna has been detected in stool samples (1, (3) (4) (5) , as has intact virus (12) . infectivity of a fecal isolate in vero e cell culture has been described (13) . actual transmission of covid-19 disease to another person through the fecal-oral route has not been reported. sars-cov-1, a coronavirus with 80% genomic nucleotide identity to covid-19 virus (1), was also detected in patient stool samples (1, 3, 14) . in the case of sars-cov-1, fecal virus was shown to remain viable for 4 days as demonstrated by infection of vero e cells in culture (14) . certainly, being infectious in cell culture is no indication that fecal virus is a contagion threat to people, but it does suggest that all of the viral rna detected in stool was and is not simply 6 excreted nucleic acid remnants. definitive proof that fecal covid-19 rna represents infective virus must await basic research. a recent review of our current understanding of covid-19 viral transmission (15) is recommended to interested readers. it should be noted that widespread fecal testing of all covid-19 patients with diarrhea is neither warranted nor prudent. there are many potential causes of diarrhea in hospitalized covid-19 patients. among them are the alterations in intestinal microflora associated with antiviral or antibiotic drug treatments, with non-enteric nutrition, or with pre-existing gi illness (16) . evidence of direct cytopathic effects on enterocytes should be explored before testing for covid-19 viral markers (16) . the indiscriminate use of fecal testing would be a waste of resources needed elsewhere and false positive results could lead to inappropriate conclusions or non-productive recommendations. potential other causes of diarrhea in patients should be explored before stool testing for covid-19 viral markers is initiated. the significance of covid-19 viral rna detected in stool samples remains to be determined, but the observation raises the question of fecal-oral transmission. if such transmission occurs, a negative test result for virus of respiratory origin might not mean that recovering patients are no longer contagious. patients with no evidence of respiratory shedding could still be contagious by fecal shedding and oral transmission. if individuals with hypochlorhydria are susceptible to infection by oral exposure, the prevalence of low stomach acid in the population could lead to further transmission. fecal-oral transmission would be in clinical insights into the gastrointestinal manifestations of covid-19 taste changes (dysgeusia) in covid-19: a systematic review and metaanalysis is sars-cov-2 also an enteric pathogen with potential fecal-oral transmission? a covid-19 virological and clinical review covid-19 and the digestive system asymptomatic sars-cov-2 infected case with viral detection positive in stool but negative in nasopharyngeal samples lasts for 42 days effect of aging on the gastrointestinal tract comparison of the human gastric microbiota in hypochlorhydric states arising as a result of helicobacter pylori-induced atrophic gastritis, autoimmune atrophic gastritis and proton pump inhibitor use inhibition of gastric acid secretion by stress: a protective reflex mediated by cerebral nitric oxide stability of sars-cov-2 in different environmental conditions. the lancet/microbe increased risk of covid-19 among users of proton pump inhibitors repurposed gi drugs in the treatment of covid-19 isolation of 2019-ncov from a stool specimen of a laboratory-confirmed case of the coronavirus disease 2019 (covid-19) infectious sars-cov-2 in feces of patient with severe covid-19 world health organization. first data on stability and resistance of sars coronavirus compiled by members of who laboratory network transmission modes of severe acute respiratory syndrome coronavirus 2 and implications on infection control: a review putative mechanisms of diarrhea in covid-19 addition to the airborne transmission already identified. thus, hypochlorhydria may lead to less efficient, but equally dangerous, transmission of covid-19 disease. key: cord-306646-6c7n0xir authors: crimi, claudia; impellizzeri, pietro; campisi, raffaele; spicuzza, lucia; vancheri, carlo; crimi, nunzio title: resumption of respiratory outpatient services in the covid-19 era: experience from southern italy date: 2020-07-02 journal: am j infect control doi: 10.1016/j.ajic.2020.06.210 sha: doc_id: 306646 cord_uid: 6c7n0xir covid-19 pandemic turned the entire health-care system organization upside-down, suspending elective activities and outpatient services. in italy, we are entering a second phase of the pandemic and several strategies has been developed to “re-open” the country, some businesses, and also health-care outpatient activities. this manuscript describes the experience of a southern italy respiratory unit for safely resuming outpatient respiratory services and preventing covid-19 transmission. coronavirus disease 2019 (covid-19) has quickly spread nationwide and has officially designated as a pandemic by world health organization (who) 1 . at the beginning of the outbreak, the need to contain transmission caused not only the lock-down of entire nations but also the shut-down of hospitals' outpatient care 2 . the sars-cov-2 infection is mainly transmitted by respiratory droplets 3 and close contact, and both respiratory clinicians and patients are at increased risk for transmission during the outpatient visit and the pulmonary function testing procedures. patients scheduled for an outpatient visit may also suffer from common respiratory symptoms that can mimic or represent undiagnosed cases of covid-19. planned pulmonary visit and pulmonary function tests (pfts) were suspended and postponed unless when deemed clinically essential, as recommended by the american thoracic society, the thoracic society of australia and new zealand and the irish thoracic society 4-7 , at the beginning of the pandemic. in some realities, covid-19 has rapidly changed the way of providing medical care, with hospitals providing "virtual visits" with remote consultations through video calls using commercially available software, to fill the gap with patients 8 . nevertheless, the ongoing medical needs of patients with pre-existing chronic respiratory diseases do not disappear during pandemics. therefore, health-care organizations should implement strategies to respond to patients' needs proactively, while maintaining physical distancing policies, preventing infection transmission, and ensuring the safety of health-care workers at the same time. in italy, we are now experiencing a second phase of the pandemic where several efforts to cautiously "re-open" the country has been made, and despite restrictions start to ease, physical distancing is not to an untimely end and we cannot lower the guard. therefore, a plan to manage the health issues of people with pre-existing chronic lung conditions is essential to prevent an inevitably indirect effect of covid-19 on these frail patients that could be devastating, increasing deaths and disabilities. moreover, a respiratory follow-up on patients who have recovered from covid-19 pneumonia is pivotal in monitoring the possible fibrotic sequela of the disease 9 . many national/international professional organizations [4] [5] [6] [7] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] have released operational indications on how to plan the re-opening of pulmonary function test laboratories proponing different approaches, but the practical organization still relies on local hospital policies, when available or on practicing physicians. we share our experience in planning for a resumption of the outpatient activity at the respiratory unit, policlinico-vittorio emanuele, catania, italy. we believe that our model takes into account several practical operative problems and propose constructive and easy-to-adopt solutions. table 1 summarizes the main challenges and identified solutions for restart respiratory outpatient clinics. patients will be informed telephonically and instructed to come on specific dates and times. at the entrance, an ad hoc trained "outpatient triage nurse" with adequate personal protective equipment (ppe) 19 will evaluate the patient providing a questionnaire for covid-19 risk assessment, detecting temperature, and assigning a level of risk (high or low risk). high-risk individuals will be referred to the emergency room department for nasopharyngeal swab testing and their outpatient visit rescheduled. this screening is an important aspect to consider since it might also trace under-recognized covid-19 patients. patients deemed at low risk will be provided with a surgical mask and an alcoholbased hand rub for hand hygiene and proceed to registration 19 . pulmonologist evaluation will be carried out in a room with minimal furnishes, with physicians equipped with ppe, a stethoscope, a portable wireless echography probe for lung ultrasound evaluation, and an oximeter. equipment will be disinfected with alcohol solutions between use for each patient 19 . pulmonary function tests will be performed in a room with a minimum presence of furnishings; the patient will be placed near the window with a plexiglass wall between he/she and the operator 9 . the technician will wear ppe 19 and sit in the same direction as the patient for protection in case of coughing or sneezing in the test area 9 . pulmonary function tests will be performed using disposable nose-clips and in-line antibacterial and viral filters 10 that will also serve as disposable mouthpieces, to prevent the transmission of infection from within the circuit. the bronchodilator testing will be performed using patients' salbutamol inhaler or a disposable aerochamber 20 . adequate ventilation of each room will be ensured using natural ventilation and an exhaust fan at the window to boost ventilation and direct airflow 21 . a 3d model of room design is shown in figure 1 . after each patient, adequate house-keeping and cleaning of the equipment and surfaces (e.g., exam bed, countertop, chair, equipment) with alcoholic solutions will be performed 19 , as well as safe waste management. pulmonary function tests will be performed only in essential cases for diagnosis of current illness, with immunocompromised patients tested first 7, 12, 14 . early afternoon appointments will be scheduled for the most severe chronic respiratory patients. covid-19 pneumonia recovered patients will be scheduled after at least 30 days of two consecutive negative swabs 13 . we need to change the way we provided care to patients so far and co-habit with the "silent enemy", since chronic severe medical conditions still exist despite covid-19, and we need to take care of them taking urgent and effective actions in continuing to assist chronic respiratory diseases while preventing infection dissemination. the proposed approach represents a prudent and easy-to-reproduce plan to restart respiratory outpatient services while dealing with this prolonged health-care emergency. we hope that our experience might provide a practical and useful guide for other respiratory units while resuming their respiratory outpatient activity. critical preparedness, readiness and response actions for covid-19: interim guidance. date last updated: 22 visualizing speech-generated oral fluid droplets with laser light scattering pulmonary function laboratories: advice regarding covid-19. date last updated date last updated: 24 peak respiratory bodies recommend suspension of lung function testing. date last updated. date last accessed date last accessed virtually perfect? telemedicine for covid-19 clinical respiratory physiology, chinese association of chest physicians, pulmonary function testing group and r date last accessed le prove di funzionalità respiratoria nell'era della pandemia da covid-19 -position paper date last updated: 9 recommendation from ers group 9.1 (respiratory function technologists /scientists) lung function testing during covid-19 pandemic and beyond. date last updated: 09 sociedade portuguesa de pneumologia. recomenda es da spp para a realiza o de provas funcionais respirat rias durante o surto covid-19 date last updated: 23 (pft).pdf?date=04012020 19. who. infection prevention and control during health care when covid-19 is suspected. interim guidance. date last updated evaluation of disposable and traditional accessory devices for use with a pressurized metered-dose inhaler natural ventilation for reducing airborne infection in hospitals acknowledgments: none. key: cord-333950-e0hd3iuu authors: maillard, jean-yves; bloomfield, sally f.; courvalin, patrice; essack, sabiha y.; gandra, sumanth; gerba, charles p.; rubino, joseph r.; scott, elizabeth a. title: reducing antibiotic prescribing and addressing the global problem of antibiotic resistance by targeted hygiene in the home and everyday life settings: a position paper date: 2020-04-18 journal: am j infect control doi: 10.1016/j.ajic.2020.04.011 sha: doc_id: 333950 cord_uid: e0hd3iuu antimicrobial resistance (amr) continues to threaten global health. although global and national amr action plans are in place, infection prevention and control is primarily discussed in the context of healthcare facilities with home and everyday life settings barely addressed. as seen with the recent global sars-cov-2 pandemic, everyday hygiene measures can play an important role in containing the threat from infectious microorganisms. this position paper has been developed following a meeting of global experts in london, 2019. it presents evidence that home and community settings are important for infection transmission and also the acquisition and spread of amr. it also demonstrates that the targeted hygiene approach offers a framework for maximizing protection against colonization and infections, thereby reducing antibiotic prescribing and minimizing selection pressure for the development of antibiotic resistance. if combined with the provision of clean water and sanitation, targeted hygiene can reduce the circulation of resistant bacteria in homes and communities, regardless of a country's human development index (overall social and economic development). achieving a reduction of amr strains in healthcare settings requires a mirrored reduction in the community. the authors call upon national and international policy makers, health agencies and healthcare professionals to further recognize the importance of targeted hygiene in the home and everyday life settings for preventing and controlling infection, in a unified quest to tackle amr. the global impact is already profound and expected to intensify, particularly among the poorest nations. 3, 4 the main driver is overuse and misuse of antibiotics in medicine and agriculture including unregulated over-the-counter sales, while global spread of resistant bacteria or resistance genes is attributed to poor infection prevention and control in healthcare facilities, and sub-optimal hygiene and sanitation in communities, confounded by poor infrastructure and weak governance. 5 in the us, between 80-90% of the volume of human antibiotic use occurs in the outpatient setting, with nearly 50% considered to be inappropriate or unnecessary. 6 without prompt action, it is estimated that rates of amr to commonly-used antibiotics could exceed 40-60% in some countries by 2030, 7 and by 2050, around 10 million people could die each year as a result of resistance to antibiotics and other antimicrobial agents. 8 almost 9 million of these will be in africa and asia. 8 in 2015, an alliance of the who, the food and agriculture organization of the united nations interventions." 9 the gap emphasizes the need for society-wide engagement, with a clear focus on "prevention first." 9 one of the five strategic objectives is a reduction in the incidence of infection through improved sanitation, hygiene, and infection prevention. 9 at least 120 countries have finalized national action plans, with the plans of more than 60 other countries under development. 10 what is striking is that the gap and national plans discuss infection prevention and control primarily in the context of healthcare facilities. (see https://www.who.int/antimicrobialresistance/national-action-plans/library/en/). by contrast, the latest 2019 uk national action plan, which sets out a 20-year vision 11 and a 5-year plan 12 for how the uk will contribute to controlling amr by 2040, offers guidelines on infection prevention in healthcare settings, but also highlights the role of the community, noting that, when it comes to infections in the community, the public have a huge part to play. 12 in recent years, demographic changes and changes in health service structure mean that the number of people living in the community needing special care, because they are at greater risk of infection, has significantly increased. the largest proportion of these are the elderly, who generally have reduced immunity to infection which is often exacerbated by other illnesses like diabetes and malignant illnesses. a decrease in immunity usually starts from 50 years old. other infection-susceptible groups include the very young, patients recently discharged from hospital, and family members with invasive devices such as catheters, as well as those whose immune competence is impaired as a result of chronic and degenerative illnesses (including hiv/aids) or because they are receiving immunosuppressant drugs or other therapies. immunosuppressed individuals are often also on other medications such as antibiotics, to help protect them from infection but can further increase susceptibility to infections such as clostridium difficile. home and everyday life settings provide multiple opportunities for spread of infection. everyday life settings include locations where normally there is no mandated hygiene policy as is typically found in clinical and educational settings; for example: work places, public transport, gyms, child day-care facilities, and shopping centers. poor hygiene is considered a major factor in the transmission of community-based infections, including gastrointestinal (gi) and respiratory tract (rt) infections such as colds and influenza, and skin infections caused by s. aureus. 14 for the elderly, communal living environments, combined with problems of fecal incontinence, create an environment in which enteric and foodborne pathogens are easily spread. as a result, the incidence of salmonellosis and campylobacter diarrhea appears to be higher among the elderly in these situations. more vulnerable 'at risk' members of society are now being looked after outside hospital settings. for example, in germany, it is estimated that approximately three quarters of all people in need of care are currently being cared for at home. 15 in the community the immunocompromised are also at risk from opportunistic pathogens such as e. coli, klebsiella spp., and pseudomonas aeruginosa, which are considered as hospital related. 15 the key steps in preventing the spread of infection, known as breaking the chain of infection, are the same regardless of setting. in the home, pathogens may have been brought home from hospital settings or enter the home via colonized or infected people, pets/domestic animals, or through contaminated food and water. 15, 16 pathogens and other microbes are shed constantly from these sources, with rapid transmission around the home mainly via hands, hand and food contact surfaces, cleaning utensils and in the air ( figure 1 ). 15 respectively. for campylobacter, counts of >100 and >1000 were isolated from 5 and 1.7% respectively. this is a concern, since it is estimated that 80% of salmonella infections originate in the home, 32 and a uk study detected campylobacter spp. in 56% of chilled retail chickens, with 7% of samples containing >1000 colony forming units (cfu)/g of skin. 33 the infectious dose of campylobacter is estimated at <500 cfu. 34 chaidez et al. 35 demonstrated that the risk of salmonella transmission from cleaning cloths via hands to mouth was far higher than the guideline levels for acceptable risk. since most pathogenic organisms die relatively rapidly, particularly on dry surfaces, the greatest risk of human exposure presents immediately after shedding from an infected or contaminated source. however some species, including s. aureus, e. coli, and other organisms such as fungal species, rhinovirus, and norovirus can survive for long periods even on dry surfaces. 36 audit studies suggest that some gram-negative organisms can form permanent reservoirs or secondary sources of contamination, particularly where moisture is present such as in sinks and drains, kitchen cleaning cloths and sponges. 37 44 the dose also depends on host susceptibility and mode of entry, and may be lower for at-risk groups in the community such as children, the elderly, and people with compromised immunity. 44 although care of increasing numbers of patients in the community, including at home can help alleviate over-burdened health systems, it can be undermined by inadequate infection control in the home and urgent focus is now needed on infection transmission in homes and community settings in addition to healthcare settings. although multidrug-resistant (mdr) bacteria (i.e. bacteria that have acquired resistance to at least one agent in three or more antimicrobial classes) are typically hospital-acquired, 50 since 2000, we have seen the emergence of new "community acquired" strains of mrsa (ca-mrsa). while healthcare-associated strains are mainly a risk to vulnerable people, for ca-mrsa, any family member is at risk and it is more prevalent among children and young adults where they cause infections of cuts, wounds and abrasions. us experience suggests the risk is greatest among those engaging skin-to-skin contact activities and contact with contaminated objects such as towels, sheets and sports equipment. transmission is common in settings such as prisons, schools and sports teams. 42 a study assessing the transmission of ca-mrsa in a university in the us, found multidrug resistant usa300 responsible for diseases including necrotizing pneumonia, severe sepsis and necrotizing fasciitis, on common touch surfaces at the university, student homes and local community settings. this suggests transfer between different locations within the community. 61 enterobacterales are a common cause of community-associated infections, including urinary tract infections and bacteremia as well as gastrointestinal infections. 51 67 kitchen sponges not only act as reservoirs of microorganisms, but also as disseminators over domestic surfaces, which can lead to cross-contamination of hands and food, which is considered a main cause of foodborne disease outbreaks. carbapenem-resistant enterobacteriaceae (cre) are also on the rise globally, but, to date, most cre infections in the us and europe have been healthcare-associated. 68, 70 although data from asia is sparse, carbapenemases have been found in bacteria recovered from drinking water in india and in food-producing animals in china. 69, 71, 72 in european studies during the 1990s, vancomycin-resistant enterococci (vre) were detected in the stools of healthy volunteers. [73] [74] [75] [76] [77] however, rates of vre, carbapenem resistance in acinetobacter infections, and mdr p. aeruginosa are thought to be low in individuals living in the community. 51 overall, the evidence suggests that mdr strains of bacteria, like any other strains of bacteria, can enter the home or other settings via people who are infected or colonized or via contaminated food and can be spread to other members of the family via hands and contaminated surfaces. if implemented effectively, home and everyday life hygiene has the potential to reduce rates of infection and the need for antibiotic prescriptions, thereby reducing the selective pressure for the development and subsequent dissemination of resistance. 15 microbiological data 14, 15 suggest that the surfaces that are most often responsible for spread of harmful microbes, at key moments include the hands themselves, hand contact surfaces, food contact surfaces, and cleaning cloths and other cleaning items ( figure 2 ). these surfaces are referred to as critical surfaces or critical control points. clothing, household linen, toilets, sinks and bath surfaces may also contribute to establishing a chain of infection, however, the risks associated with these surfaces are typically lower as they rely on the hands and other "chain links" to disseminate infectious microbes to cause human exposure. an important aspect of targeted hygiene is hygienic cleaning -as opposed to visible cleaningto break the chain of infection. this is achieved using hygiene procedures (products plus process) to reduce pathogenic microorganisms on critical surfaces to a level where they are no longer harmful to health -thereby preventing ongoing spread. 15, 84 several methods exist to achieve such reduction in potential pathogens: mechanical/physical removal using dry wiping, soap or detergent-based cleaning together with adequate rinsing, inactivation or eradication using a disinfectant on hard surfaces or an alcohol-based sanitizer on the hands, or a physical process such as heating (to ≥60°c/140°f) or ultraviolet treatment. most frequently, a combination of these approaches is likely to be used. 15, 84 when developing hygiene procedures aimed at breaking the chain of infection, the goal should be to ensure that each procedure is appropriate to its intended use. in recent years, risk modelling has been developed in order to achieve this. 80 quantitative microbial risk assessment (qmra) was originally developed for ensuring water quality and is increasingly being used to develop infection prevention control strategies in other settings, including healthcare. 85, 86 qmra is a scientifically-validated approach that uses published data to model the chain of infection and estimate safe residual level of contamination at critical points in the chain. 84 , 87 this information is then used to estimate the log reduction required to reduce contamination to a safe level. based on these estimates, tests modelling use conditions can be used to develop effective hygiene procedures to achieve the required reduction. the approach is set out in more detail by bloomfield et al. 84 in the past, recommendations on selection of hygiene procedures for home and everyday life were based on the health status of family members, and it is still argued by some that disinfectants should only be used in situations where people are infected or at increased risk of infection. 87 although there is data to show that hygiene is important in preventing transmission of mrsa colonization and infection in the domestic environment, further investigation is required to demonstrate the full extent to which poor home hygiene may contribute to the burden of foodborne infection associated with antibiotic resistant strains. quantifying the impact of hygiene on the burden of infection in home and everyday life is challenging because of the large population sizes required to generate significant results, and difficulties in conducting studies involving multiple interventions. most data have been generated from single intervention studies -primarily hand hygiene -where meta-analyses show a positive impact on gi and rt infections. [91] [92] [93] children who attend day-care centers have significantly more infections than those who do not. the most common are rt and gi infections, and the risk of otitis media is almost twice that of children remaining at home. 94 studies in day-care centers and schools in which hand hygiene was combined with cleaning and/or disinfection of environmental surfaces indicate a positive impact on illness rates and reduction in the use of antibiotics. [94] [95] [96] [97] in an intervention study 96 reduction of antibiotic prescriptions for rt infections in a group who used hand sanitizers compared with a control group. 98 another 2018 intervention study 99 found that children were prescribed antibiotics for significantly fewer weeks in day care centers using specific disinfecting products and cleaning protocols than centers that continued to use their standard procedures and products (rr=0.68 [95% ci 0.54, 0.86]; p=0.001) -a relative risk reduction of almost onethird. to the best of our knowledge, only one study on the impact of targeted hygiene in the home has been conducted. 100 this study, conducted among low-income communities in cape town, south africa, evaluated the impact of hygiene education alone and education in combination with hand washing with soap at critical times, bathing at least three times a week, cleaning/disinfecting household surfaces at critical times, and proper waste disposal. 100 qmra is also now being used to estimate the impact of hygiene interventions on infection in community settings. 102 haas et al. 103 concern has been expressed as to whether expanding use of microbicidal products, in the home and everyday life may contribute to the rise in amr. 105 sub-lethal levels of microbicides can induce stress on bacterial cells, causing expression of mechanisms that reduce the biocide concentration at the bacterial target site further and allow the bacterial cell to repair. 106, 107 these include overexpression of an efflux system, membrane regulatory changes, and changes in membrane permeability and composition. 107 these same mechanisms can produce changes in the susceptibility profile to unrelated antimicrobials. 107 in other words, the use of microbicides may cross-select for antibiotic resistance and be associated with reduced antibiotic susceptibility to clinically significant levels (recently reviewed by maillard 107 ). factors inherent to the microbicide (i.e. concentration, formulation, mechanism of action), the microorganisms (i.e. type/strain, metabolism, resistance mechanisms), and product usage (e.g. concentration, exposure time), all impact on product efficacy. 107 decreases in efficacy, for example, following shorter contact time or product dilution, will lead to bacterial survivalantimicrobial damage caused by a sub-lethal concentration of a microbicide is likely to be repairable. 107 a number of expert reports commissioned in the last 10 years have highlighted laboratory studies linking microbicide use with reduced antibiotic susceptibility. however, these reports conclude that there is little evidence for this effect occurring in real-life clinical practice, and have called for further research into whether microbicide use influences antibiotic resistance in the community. 108-111 rutala et al. (2000) found that the frequency of occurrence of antibiotic resistance in environmental isolates from homes was much lower than for clinical isolates from a hospital intensive care unit and an outpatient setting where there was routine extensive use of antibiotics. 112 two studies were carried out to investigate whether antibiotic resistant strains were more likely to be found in homes where antibacterial products were used, compared with homes where they were not. 113, 114 samples were collected from houses in the usa and uk of 30 users and nonusers of antibacterials. susceptibility tests against antibiotics and antibacterial agents (triclosan, pine oil, bac and para-chloro-meta-xylenol) were carried out on the bacteria isolated. the authors concluded that there was no evidence that antibiotic resistant strains occurred more frequently in user homes compared with non-user homes. a 1-year study by aiello et al (2005) also showed that household use of antibacterial cleaning products was not a significant risk factor for occurrence of antibiotic resistant isolates from hands. 115 despite more than 20 years of research, there is still no conclusive resolution to the question of whether and to what extent; microbicides might contribute to amr in clinical practice. in light of laboratory data, which indicates that microbicide-induced amr is biologically plausible for some types of microbicides, it is concluded that use of microbicides needs to be prudent and appropriate and that the products containing them must be used at recommended concentrations and with the appropriate contact time. targeted hygiene works to ensure that use of disinfectants and hand sanitizers (i.e. microbicides used at the correct concentration and contact time) are confined to situations where there is identifiable risk of spread of harmful microorganisms, ensuring that they play an essential role in tackling amr. the need for antibiotic prescribing may in fact increase if disinfectants and hand sanitizers are not used as indicated, due to the increased risk of infection and survival of bacteria bearing amr determinants. these could potentially spread to other areas in the home and on into the community. it is important to note also that preventing viral infections as well as bacterial infections, such as those that cause respiratory and gi infections, can also have a role in reducing amr as this will eliminate the potential for mis-prescribing or misuse of antibiotics. in in 2015, an estimated 663 million people around the world were drinking from unimproved water sources, and 2.4 billion had no access to improved sanitation -the vast majority of these were in sub-saharan africa and south asia. 119 it is estimated that 2.3 billion people lack the use of sanitation facilities which are not shared with other households, 120 42 as with studies conducted in hics, the highest levels of contamination in lmics are typically found in moist locations such as kitchen sponges and dishcloths. [122] [123] [124] the key question, however, is whether, and to what extent, the incidence and levels of potentially harmful pathogens (and thus infection risks) are higher in homes without access to adequate water and sanitation. sinclair and gerba 124 monitored fecal coliforms, total coliforms, e. coli and heterotrophic plate count bacteria on household surfaces in 8 homes that had improved latrines (i.e. a pour-flush latrine) in a rural village of cambodia, and compared the results with similar data from homes in the us 38 and japan. 39 fecal coliform levels in cambodia were found to be highest in moist locations such as the plastic ladle used for sink water, the toilet seat surface, and the cutting board surface. 124 for e. coli, the mean log cfu per 4 cm 2 ranged from 0.5 to 4.0, with highest counts found on the top of the squat toilet, the wash basin, and the floor around the toilet. fecal coliform levels were 100-fold higher on these surfaces in cambodia than on equivalent surfaces in the us and japanese studies. in lmics, due to a lack of basic sanitation, good hand hygiene is of vital importance. 116 globally, it has been estimated that only 19% of the population washes its hands with soap after contact with excreta. 93 observations show that hand washing with soap is undertaken in an ad hoc manner, 116 with many households having no access to handwashing facilities. 125 unsurprisingly, studies in lmics have reported high levels of fecal indicator bacteria on the hands of household members, [126] [127] [128] with one study correlating presence of fecal contamination on the hands with the prevalence of gastrointestinal and respiratory symptoms within the household. 126 a cochrane review showed that improving hand washing practices probably reduces diarrhea episodes in child day-care centers in both high income countries and among communities living in low to middle income countries by as much as 30%. 92 the evidence set out in this paper suggests that, if combined with measures ensuring clean water and adequate sanitation, targeted hygiene practices in home and everyday life settings could make a significant contribution to tackling amr through infection prevention and a consequential reduction in antibiotic prescribing. this is true in all areas of the world including low-income countries. additionally, the evidence suggests that hygiene promotion would contribute to preventing the transmission of resistant bacteria from the home and everyday life settings, into healthcare settings, and back into the community. further research is still needed to evaluate the extent to which this might occur, especially in communities in low income countries. to be effective, hygiene interventions need to consider all aspects that are likely to affect the outcome. this includes a reduction of antibiotics from the food chain and the environment, improved hygiene education and availability of appropriate products as well as the provision of clean water and improved sanitation. based on these findings, the authors of this paper issue a call to action to national and international health policy makers, health agencies, and healthcare professionals to give greater recognition to the importance of hygiene in the home and everyday life and development and promotion or more effective codes of practice for hygiene in the home and everyday life as part of national action plans to tackle amr. although the precise impact of hygiene on transmission of infection between community and healthcare settings needs further investigation, it is important to recognise, that reducing the need for antibiotic prescribing and the circulation of amr strains in healthcare settings cannot be achieved without also reducing circulation of infections and amr strains in the community. we cannot allow hygiene in home and everyday life settings to become the weak link in the chain. the development of this position paper was supported by an educational grant 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cord-291679-jfxqipt8 authors: yang, seongwoo; cho, sung-il title: middle east respiratory syndrome risk perception among students at a university in south korea, 2015 date: 2017-06-01 journal: am j infect control doi: 10.1016/j.ajic.2017.02.013 sha: doc_id: 291679 cord_uid: jfxqipt8 background: the 2015 middle east respiratory syndrome (mers) outbreak in south korea was a serious threat to public health, and was exacerbated by the inappropriate responses of major institutions and the public. this study examined the sources of confusion during the mers outbreak and identified the factors that can affect people's behavior. methods: an online survey of the risk perception of university students in south korea was performed after the epidemic had peaked. the questionnaire addressed the major social determinants in south korea during the mers epidemic. the analysis included data from 1,470 subjects who provided complete answers. results: the students had 53.5% of the essential knowledge about mers. women showed higher risk perception than men, and trust in the media was positively associated with risk perception (p < .001). additionally, risk perception was positively associated with overreaction by the public (odds ratio, 2.80; 95% confidence interval, 2.17-3.60; p < .001). these findings suggest that media content affected the public's perception of mers risk and that perception of a high level of risk led to overreaction. conclusions: risk perception was associated with most of the social factors examined and overreaction by the public. therefore, providing accurate information and data to the public, establishing trust, and facilitating the development of an attitude will all be important in future crises. the first middle east respiratory syndrome (mers) case was confirmed in south korea on may 20, 2015. the last case was diagnosed on july 4 and summed up to a total of 186 confirmed cases, almost half of which were in seoul. after that, south korea officially declared the end of the mers epidemic on december 23, 2015. during the mers outbreak, 38 died and 16,752 had been quarantined (fig 1) . 1 the case fatality rate of mers in south korea was approximately 20.4%, lower than that on the arabian peninsula (approximately 45%). 2 public apprehension was exacerbated because the government did not disclose timely information about the status of the epidemic or hospitals' names and procedures related to mers infection. therefore, the public were unaware of the appropriate actions to take, but were provided with relevant information by the media. indeed, several citizens created web sites that listed confirmed and suspected mers patients. 3 however, the public also received inaccurate information from the internet and social media; this increased the level of concern over mers and resulted in rumors. the government of south korea stated that any person who disseminated an untrue rumor would be prosecuted, but this failed to reduce the level of panic. although this action was supposed to prevent secondary damage, it was similar to the censorship of the media in china, where the propaganda departments of the chinese communist party directly supervised the media flow when the severe acute respiratory syndrome (sars) outbreak occurred in 2003. 4 the chinese government attempted to maintain political, social, and economic stability by minimizing the sars crisis through the withholding of information; however, a reverse effect occurred. nevertheless, the chinese government assigned responsibility for censorship of the media, including the internet, to local agencies. 5 in the new media age, in which social media (including the internet, short message services, and mobile applications) are centralized, the government restricts freedom of expression in the same way as it has restricted such freedom among traditional media sources, such as newspapers, radio, and television. 6 the control of the acquisition of information is more difficult in this new age because social media are tools not only for the dissemination, sharing, and seeking of health information but also for the expression of feelings and the sharing of personal experiences and opinions. 7, 8 therefore, organizations need to build effective communication tools to respond to emerging infectious disease (eid) outbreaks because the public may express scientific skepticism about scientific topics and participation in decision-making. 9 during epidemics, people usually require guidance on how to behave from a trusted source. the government and public institutions are the ideal sources because people tend to rely on the national administration. for this reason, trust in these institutions plays a main role in the public's acceptance of policies and actions. 10 the world health organization suggested that outbreak communication should incorporate the following 5 key factors: (1) building, maintaining, or restoring trust; (2) announcing early; (3) maintaining transparency; (4) understanding the public; and (5) planning of all aspects of the response to an outbreak. 11 therefore, risk communication enhances the decision-making ability of laypeople, and can be examined by assessing risk perception. 12 trust in not only the government and public agencies but also in the media and other institutions may be associated with risk perception. therefore, the instigation of fear among the public by the media may contribute to social panic, particularly in emergency situations. the term risk perception usually refers to individuals' judgments about and evaluations of hazards to which they might be exposed. 13 therefore, risk perception might be among the social phenomena related to exposure to the risk of disease. in addition, perceived risk influences health behavior both positively and negatively. 14 during the mers outbreak in south korea, negative behaviors were observed, such as oversensitive or inappropriate reactions. some children of health care workers at hospitals treating mers patients were prevented from attending school. meanwhile, self-quarantined subjects occasionally escaped out of their homes until the level of infection subsided. these reactions of citizens reflect distrust in the government and accelerated noncompliance with the directions provided by the korea centers for disease control and prevention. this finding is important because overreaction is an indicator of the level of trust in the government among the public and may provoke another social problem related to moral panic. 15 fear causing the behaviors described previously mentioned is likely related to risk perception and a low level of trust in the government and society. however, because risk perception may be related to a number of unknown determinants, it is important to identify factors that may affect risk perception. sjöberg examined risk perception using several approaches, 16 and reported that 30%-40% of risk perception could be explained by risk sensitivity, attitude, and a specific fear model. in other models, <20% of risk perception was explained. there were also some studies regarding risk perception. previous studies of risk perception related to nuclear explosions and infectious diseases addressed the relationship between perceived risk and various social predictors, such as knowledge, social trust, and attitude. 17, 18 however, previous literature on the determinants of risk perception has been limited. the aim of this study was to determine whether risk perception was associated with personal and social variables, including trust in the media, the health care field, and government. additionally, we sought to identify the associations of risk perception and social variables with compliance with self-quarantine guidelines and overreaction during the mers epidemic. in this study, knowledge, trust, personal characteristics, and other social determinants were considered the main factors affecting risk perception and overreaction. we developed a questionnaire based on previous studies of perception of the risk of sars and ebola conducted outside of south korea. [19] [20] [21] the questionnaire comprised the following 5 components: knowledge of mers (9 items), risk perceptions about mers (7 items), trust in society and governmental health policy (5 items), preventive behavior (11 items), and particular situations relating to mers (7 items). sociodemographic information was also obtained. korean-and english-language versions of the questionnaire were developed to enable inclusion of foreign students in the survey (supplementary appendix s1). the english-language version of the questionnaire was backtranslated into korean for quality control purposes. questions regarding knowledge of mers were used to estimate the level of accuracy of the following information: the selfrecognized level of knowledge, the concept of mers, route of transmission, the concept of close contact, symptoms, the concept of the incubation period, characteristics of mers, self-quarantine, and treatment of mers. evidence for these questions was from the mers response guidelines of the korea centers for disease control and prevention. 22 the cumulative knowledge score of the participants was calculated (range, 0-8; 1 point for each correct response [ie, in agreement with the evidence]). because all questions referred to information provided in governmental guidelines, the survey was regarded as providing an estimate of respondents' essential knowledge. risk perceptions were assessed using revised versions of the ebola risk perception surveys conducted in germany 20 and israel. 21 risk perception was assessed using levels of agreement with the following statements: "i think that i will contract mers if i come into contact with a mers patient (risk perception 1)," "i think that i might contract mers even if i do not come into contact with a mers patient (risk perception 2)," "my health will be severely damaged if i contract mers (risk perception 3)," "i think mers is more severe than other respiratory diseases (risk perception 4)," "even if i fall ill with another disease, i will not go to hospital because of mers (risk perception 5)," "mers will inflict serious damage on my community (risk perception 6)," and "mers may spread in korea again someday (risk perception 7)." the questions were responded to on a 5-point likert scale. in addition, because risk perception is a continuous variable, it was classified into 4 groups according to quantile (very high, high, low, and very low). a revised questionnaire regarding trust in society, media, and health policy was developed from the korean general social survey (kgss). the kgss has been validated in south korea and is conducted periodically nationwide. several questions in the kgss estimate the levels of trust among respondents in society, the media, central and local government, the national assembly, the medical profession, and nongovernmental organizations (ngos). such trust was expected to be associated with trust in health policy because governmental actions tend to reflect governmental policies. finally, questions regarding particular situations related to mers were classified into the following 2 categories: overreaction and compliance with self-quarantine. a large proportion of the population of south korea was unaware of the appropriate actions during the mers epidemic. these categories measure the characteristics of individuals not inclined to abide by the self-quarantine guidelines. therefore, this section assessed the following personal characteristics: degree of optimism about the health policies of south korea, willingness to sacrifice for society, responsiveness to an emergency situation, and attitude toward self-quarantine and overreaction. attitude toward self-quarantine was measured with a question asking whether respondents were willing to prioritize quarantine adherence above all personal needs (responses were categorized as yes and no). the overreaction section comprised the following 2 questions: (1) how would you react if you realized your children were in the same class as those of someone suspected (or confirmed) to have mers (including school and extracurricular activities)?; and (2) how would you react if you realized your children were in the same class as those of medical workers at hospitals with mers patients (including school and extracurricular activities)? the responses to the formerly involved overreactions, for example, "(do not) allow my relatives or children of my family to attend school," and those to the latter were the opposite, such as "i think children of medical workers at hospitals with mers patients should (not) be allowed to attend school." each question was assumed to indicate overreaction to the behavior of oneself and others. a presurvey including 152 participants was performed to assess the reliability and validity of the questionnaire and the direction of the responses. the presurvey was conducted both in the field using a tablet personal computer or laptop and online using an online survey application (surveymonkey, san mateo, ca). data for the main survey were collected by e-mailing students at seoul national university. the cronbach α values for the 2 new measures developed for this study, trust and risk perception, were 0.8307 and 0.6755, respectively, in the main survey. students at seoul national university were selected for the study. we considered this population appropriate for several reasons. first, they are not likely to include people associated with hospitals. second, younger individuals tend to have access to up-to-date information through smartphones or the internet. third, the subjects had similar levels of academic attainment and demographic characteristics. finally, because of the need for a timely investigation, this setting assured the benefit of accessibility and cost-efficiency. for the main survey, e-mails containing the link connected to the online survey setting were sent to all of the 30,727 students at seoul national university, including undergraduates, postgraduates, and foreign students. survey e-mails were sent on 3 occasions at weekly intervals from october 6-23, 2015. of the 30,727 students, 1,487 (4.8%) provided a complete response. after exclusion of those with missing responses, a total of 1,470 subjects were included in the study. this survey and research were approved by the institutional review board of seoul national university (no. 1508/002-003). relationships between levels of risk perception and demographic factors were evaluated by the χ 2 test, and the mean and se values were estimated. to evaluate correlations among independent variables, spearman correlation coefficients were calculated. correlation coefficients among explanatory variables were all <0.5, which was regarded as not having multicollinearity. 23 variables were selected for inclusion by stepwise calculation of the akaike information criterion. moreover, to prevent multicollinearity, a test of variation inflation factors was performed for each analysis. to assess the associations of demographic factors, knowledge, trust in social organizations, intention to sacrifice, and responsiveness to emergency situations with risk perception, multiple linear regression analyses were used. each question regarding risk perception was aggregated to produce a cumulative score indicative of the overall effect of risk perception. prior to analysis, the variables were tested using a q-q plot to verify the normality of their distribution andwith the exception of knowledge-were confirmed to be continuous because the ordinal values differed only slightly from a normal distribution. 24 risk perception was estimated on a scale of 1-7, and its relationship with predictors was assessed. in addition, to identify the association of risk perception with overreaction to the epidemic and compliance with self-quarantine, multiple logistic regression analyses were performed. odds ratios (ors) were calculated for self-quarantine and overreaction. analyses were conducted using sas version 9.4 (sas institute, cary, nc). sociodemographic variables and levels of risk perception are shown in table 1 . more than half of the participants were men (57.01%), 24-26 years of age (30.54%), citizens of south korea (95.51%), and postgraduate students (52.04%). a high frequency of risk perception was detected in women (n = 152; 52.6%), those 24-26 years of age (n = 97; 33.56%), students from south korea (n = 281; 97.23%), and postgraduate students (n = 166; 57.44%). the mean knowledge score was 5.35 ± 1.41 out of 10. therefore, respondents had approximately 53.5% of the essential knowledge about mers. the mean score for trust in the medical profession was higher than those for other social components (3.63 ± 0.95); the mean score for trust in the central government was lowest (2.37 ± 1.03) ( table 2 ). in terms of the media section, the item regarding trust in newspapers was excluded from the analysis because of its lack of validity according to the variable selection process. women had a higher risk perception score than men, not only overall (by 0.17/5 points; β = 0.17; p < .001), but also in all other risk perceptions from 1-7 (table 3) . older age was negatively associated with risk perception 2 (concern over contracting mers through indirect contact) (β = −0.07; p = .004) and positively associated with risk perceptions 4 (considering mers to be more severe than other respiratory diseases) (β = 0.09; p < .001), 6 (concern over damage to the community because of mers) (β = 0.05; p = .026), and 7 (future reemergence of mers) (β = 0.06; p < .001). in addition, only risk perception 6 (damage to the community) was significantly positively associated with korean ethnicity (β = 0.44; p < .001). knowledge influenced only risk perceptions 1 and 7. that is, knowledge was related to concern over contracting mers through direct contact (β = 0.04; p = .015) and reemergence of mers (β = 0.05; p = .004). knowledge was associated with risk perception, which does not support the hypothesis of this work. trust in the media (broadcasting) was positively associated with cumulative risk perception (β = 0.06; p < .001) and risk perceptions 1 (concern over contracting mers through direct contact), 3 (severity of mers), 4 (considering mers to be more severe than other respiratory diseases), and 6 (concern over damage to the community because of mers). however, trust in the medical profession (β = −0.04; p = .027) and the central government of south korea (β = −0.05; p = .014) was negatively associated with overall risk perception. risk perceptions 2 and 4 (relevant to disease traits) were related to trust in the medical profession. in addition, risk perceptions 5, 6, and 7 (relevant to community traits) were related to trust in the central government. in contrast, trust in local government (β = 0.04; p = .046) and ngos (β = 0.06; p < .001) was positively associated with risk perception. trust in local government and ngos was associated with risk perceptions 5 and 6 and risk perceptions 1, 3, 4, and 6, respectively. compared with the results for trust in the central government, those for trust in local government seemed to have similar effect sizes, but with a different direction of estimates. however, trust in ngos was associated with the perception of the risk of transmission and that to personal health. this suggests that ngos are believed to contribute to communities in various ways, including by providing medical services. trust in society was not associated with the overall risk perception but was negatively associated with concern over damage to the community (β = −0.11; p = .002). finally, trust in health policy was negatively associated with risk perception (β = −0.05; p = .014). risk perceptions 2 and 7 were related to trust in the health policy of the government of south korea. optimism about future health policy (β = −0.04; p = .024), willingness to sacrifice (β = −0.06; p = .004), and active responsiveness to an emergency (β = 0.18; p < .001) were associated with risk perception. only risk perception 3 was associated with optimism regarding health policy (β = −0.09; p = .009). willingness to sacrifice was negatively associated with risk perceptions 1, 3, and 5. in addition, responsiveness to an emergency was positively associated with risk perceptions 1, 2, 3, 4, 6, and 7. therefore, respondents who were pessimistic about health policy and unlikely to sacrifice themselves in specific situations and respond actively to an emergency exhibited a higher perception of risk. ors were calculated to estimate the associations among risk perception, knowledge, personal characteristics, and compliance with self-quarantine ( table 4 ). the proportions of men and women who indicated they would comply with the self-quarantine guideline were 82.7% and 87.2%, respectively. women were more likely to comply with self-quarantine (or, 1.50; 95% confidence interval [ci], 1.10-2.06; p = .010), as were older subjects (or, 1.22; 95% ci, 1.01-1.46; p = .037) and those with a greater level of knowledge (or, 1.22; 95% ci, 1.10-1.35; p < .001). additionally, subjects with more trust in the medical profession (or, 1.35; 95% ci, 1.14-1.60; p = .001) and those who were willing to sacrifice (or, 1.50; 95% ci, 1.20-1.88; p < .001) and actively respond to emergencies (or, 1.31; 95% ci, 1.03-1.67; p = .028) were also more likely to comply with a self-quarantine order. the proportions of positive responses to items about overreactions in one's own behavior (self-behavior) and overreactions in response to the behavior of others were 79.9% and 42.9%, respectively. knowledge (or, 0.90; 95% ci, 0.82-0.99; p = .037) and trust in society (or, 0.81; 95% ci, 0.66-0.98; p = .029) were negatively associated with overreaction in self-behavior (table 5 ). however, responsiveness to an emergency (or, 1.32; 95% ci, 1.05-1.66; p = .016) and risk perception (or, 2.80; 95% ci, 2.17-3.60, p < .001) were positively associated with overreaction in self-behavior. in terms of overreaction to the behavior of others (table 6) , korean respondents (or, 0.486; 95% ci, 0.28-0.84; p = .010), those with a greater level of knowledge (or, 0.79; 95% ci, 0.73-0.86, p < .001), and those with a higher level of trust in the medical profession (or, 0.70; 95% ci, 0.61-0.80, p < .001) were unlikely to overreact to the behavior of others. however, respondents with a higher level of trust in local government (or, 1.19; 95% ci, 1.02-1.38; p = .024) and higher risk perception (or, 1.86; 95% ci, 1.52-2.28, p < .001) were more likely to overreact to the behavior of others. therefore, risk perception was associated with a change in behavior during an epidemic. the findings of this study indicate that risk perception is associated with various social factors. risk perception was correlated with sex and the level of trust in social organizations. these findings indicate that risk perception interacts with demographic and personal attitudinal factors at a collective level, as previously suggested. 25 women had a higher risk perception than men. trust in the media (television), local government, and ngos exhibited positive associations with risk perception, whereas trust in central government, the medical profession, and health policy exhibited negative ones. these results suggest that people are aware of the different roles of central and local government. additionally, these results identify the types of determinant that affect whether people overreact when an infectious outbreak occurs. women and those with low levels of trust in central government, the medical field, and health policy were more likely to overreact. on the other hand, people with high levels of trust in the media, local government, and ngos may be hypersensitive when an eid outbreak occurs. furthermore, the higher risk perception was associated with only overreaction, not compliance to self-quarantine. hypersensitivity that leads to overreaction can be explained by perceived media dependency 26 ; however, this may have been related only to television in this research. moreover, differences in the effects of trust in central and local governments on risk perception may be explained by south koreans' perceptions of the roles of these government bodies. central and local governments do not always appear to smoothly coordinate the emergency response, and this may be related to ongoing challenges about decentralization from the central governmental system. 27 another important finding is related to the role of the media during a crisis. in this study, trust in the media positively affected risk perception and overreaction, supporting that the mass media influence perceptions of disasters and risks; however, they cannot change an epidemic event itself. 4 restrictions on the availability of information by the government can exacerbate the impact of a disaster, especially in the new media age, in which person-centered media is emphasized; this was the case in the 2003 sars outbreak in china and the 2015 mers outbreak in south korea. regardless of the political system (ie, even in democratic states), the absence of risk communication may yield unexpected results. therefore, the world health organization outbreak guidelines 11 regarding building public trust and establishing a transparent flow of information need to be followed. respondents in this study were moderately knowledgeable about mers, possessing 53.5% of the essential knowledge. this finding may reflect a higher mean level of education of the respondents compared with the general population, but indicates that the public is not ignorant about environmental and health-related matters. 28 from another point of view, this finding can be said to contradict the deficit model, which holds that the public lacks knowledge. 29 on the emergence of a novel infectious disease, people tend to be receptive to health-related information conveyed by new media, including the internet and mobile phones. for these reasons, the role of the mass media is particularly important because they usually provide widespread coverage of eids and convey information to the public. 30 furthermore, the level of knowledge about mers was not associated with risk perception. this is not in agreement with a previous report of a correlation between knowledge and perception of the risk of nuclear explosions. 31 notwithstanding these considerations, knowledge of mers was directly associated with overreaction and compliance with self-quarantine. this suggests that greater knowledge of unfamiliar diseases reduces the likelihood of undesirable behavior, which can lead to social problems. personal characteristics, including willingness to sacrifice and responsiveness to an emergency, were negatively and positively, respectively, associated with risk perception. in addition, while responsiveness to an emergency was associated directly with overreaction and compliance with self-quarantine, willingness to sacrifice was associated only with compliance with self-quarantine. personal characteristics were associated with responsive behaviors; however, the reasons for these associations could not be determined. one possibility is nationalism. individuals who regard nations as abstract communities with shared emotional bonds governed by rules and/or norms tend to be altruistic. 32 therefore, people in table 5 associations of risk perception, knowledge, and personal characteristics with overreaction in one's own behavior societies governed by established, systematic rules are less likely to exhibit unusual behaviors that may lead to social panic. moreover, inaccurate information is disseminated through social media platforms, such as twitter, facebook, and google. the enormous influence of social media during the 2014-2015 ebola outbreak in west africa has led to exaggerated concerns even among the population in the united states with negligible risks. 33 indeed, the mass media can also incite panic, which is related to fear and antisocial behavior 34 ; however, when they do their job properly, they can inform the public accurately about current conditions. two studies in which a mobile health communication tool was used demonstrated the effectiveness of a social media-based approach in terms of changing vaccination behavior. 35, 36 furthermore, the provision of appropriate and timely public health information by social media and the mobile health tool could accelerate the detection of disease outbreaks and enhance the public's response, 37 thereby minimizing adverse health and economic effects. 38 the findings of our study are depicted in schematic form in figure 2 . in this model, risk perception was related to various factors such as sex, trust, and other personal characteristics. there was a notable aspect of risk perception: it was directly associated with overreaction, but not with compliance to self-quarantine. this suggests that risk perception motivates self-protective behavior, possibly resulting in overreaction. however, it does not automatically result in compliance to quarantine, which is generally perceived as protecting others, rather than oneself. in this sense, risk perception is a double-edged sword: at an optimal level, it helps the public protect themselves from infection and thereby deter the spread of epidemic; however, when excessive and characterized by fear, it can lead to other social problems, such as overreaction and discrimination. sandman reported that risk perception is comprised of hazard and outrage. 39 the mers outbreak caused fear and anxiety among the population, which might have resulted in an overreaction to both the response of the government and the behaviors of themselves and others. 40 our model also points to the importance of trust in medical experts and proper knowledge. these 2 factors demonstrate the potential to maximize the benefit by promoting compliance and reducing overreaction. therefore, risk communication should not just scare people, but should create a context in which there is trust and a flow of knowledge and clear information between the authorities and the public. these conditions should prevent adverse effects, particularly in democratic states. the existing literature emphasizes these essential components of risk management and risk communication. 41, 42 to date, there are a limited number of studies on risk perception of infectious diseases (including mers); therefore, this work makes an important contribution to the field. several factors affecting perceived risk were evaluated (eg, trust in the media or health policy, personal characteristics), which were not assessed in previous studies. although knowledge and trust have been previously reported to be associated with perceived risk, 17, 18 this study further explored possible effects of risk perception and their implications in responding to an epidemic. eids are unfamiliar to the general public and are likely to be overestimated in the risk, 31 possibly leading to social panic. to prevent this, it is important to boost the risk communication with fostering trust and relevant knowledge, which requires transparency. this study had limitations. first, the survey involved students at a university; therefore, the participants might have different levels of concern about the epidemic compared with the general public. however, the participants represented the younger population with a homogeneous educational level with fewer confounding factors. therefore, the findings were still likely meaningful for understanding the characteristics of risk perception in the essence. second, the response rate was rather low (4.8%). most online surveys have much lower response rates than person-to-person interviews. 43 the students who had a greater perception of the risk might have been better motivated to participate in the study. even if the associations found in this study may be weaker in a larger population, it is informative to identify the direction and structure of the interrelationships among the factors. future studies should investigate whether the findings from this study are applicable in more diverse populations. furthermore, developing and testing more specific approaches to building trust and sharing knowledge during an epidemic would be needed. in responding to the public health emergency, collaboration is important among various social institutions, such as central and local governments, media, and medical community. more research is needed to explore the roles and relationships of these agents for effective risk communication. in conclusion, risk perception was found to be associated with social trust and personal attitudes toward emergency situations in this study. risk perception was associated with overreaction, possibly by fear-induced changes in behavior. however, knowledge about the nature of disease mitigated this possibility and enhanced compliance to quarantine guidelines. understanding the determinants of risk perception contributes to effective communication. building trust and sharing knowledge are important to ensure a rapid response to disease outbreaks, and to prevent unnecessary behaviors among members of the public. taking stock of the first 133 mers coronavirus cases globally-is the epidemic changing? middle east respiratory syndrome in the republic of korea: transparency and communication are key media, crisis, and sars: an introduction how censorship in china allows government criticism but silences collective expression convergence, content industries and media governance public anxiety and information seeking following the h1n1 outbreak: blogs, newspaper articles, and wikipedia visits pandemics in the age of twitter: content analysis of tweets during the 2009 h1n1 outbreak risk communication and infectious diseases in an age of digital media 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and management hazard versus outrage in the public perception of risk. effective risk communication mers-cov outbreak in south korea-public policy trumped by fear and politics social trust and the management of risk risk management in post-trust societies the adequacy of response rates to online and paper surveys: what can be done? we thank all members, hye-rin park, jee-eun yi, kang-jin kim, nam-kyu cho, nara lee, and yunisa astiarani who participated in conducting the survey together in community health field training, one of the programs of a master's course at the graduate school of public health. we also thank the supporting from bk21 plus. supplementary data related to this article can be found at http://dx.doi.org/10.1016/j.ajic.2017.02.013. key: cord-331848-tysxrc4o authors: lammers, daniel t; jones, ian f; marenco, christopher w; morte, kaitlin r; mcclellan, john m; eckert, matthew j; bingham, jason r title: safety code blue! assessing the use of blue surgical sterilization wrap for homemade respirator masks during the covid-19 crisis. date: 2020-07-15 journal: am j infect control doi: 10.1016/j.ajic.2020.07.021 sha: doc_id: 331848 cord_uid: tysxrc4o the use of surgical sterilization wrap for respirator masks during the covid-19 crisis has become a popularized personal protective equipment alternative option due to claims supporting its ability to meet n95 standards. this study sought to assess these claims using standardized filter testing. the tested material failed to meet n95 standards and suggests its use may place medical personnel at increased risk of harm when managing covid-19 patients. critical shortages of medical-grade personal protective equipment (ppe) during the ongoing covid-19 crisis have left the healthcare system in a vulnerable state. in response, numerous innovative, self-made ppe practices have surfaced. while many well-intentioned individuals, organizations, and healthcare systems are turning to these approaches, objective safety data to support their use is lacking. surgical sterilization wrap has become an increasingly popular material for respirator mask use based on claims that these masks pass n95 fit testing, a qualitative test to detect leakage of irritants around the mask-skin interface, and are easily made from readily available materials ( figure 1 ). 1 while appealing, quantitative data regarding the sterilization wrap's ability to filter viral particulate matter is not present within the current literature. although n95 fit testing is a required step for the safe and effective use of respirator masks, it is not sufficient and each mask must pass a set of strict guidelines implemented by the national institute for occupational safety and health (niosh) in order to receive the n95 rating. we sought to subject the popularly used surgical sterilization wrap material used for respirator mask creation to these strict quantitative niosh n95 standards via standardized industrial testing. o&m halyard h600 surgical sterilization wrap was utilized for this study. the sterilization wrap was subjected to tsi 8130 automated filter testing in accordance with niosh standards for the n95 respirator mask. standardized testing to include penetrance assessment with a sodium chloride aerosol comprised of a 0.075 µm count median diameter and a 0.3 µm aerodynamic mass median diameter at flow rates of 85l/min was performed. the sterilization wrap was tested in single and double layers and compared to n95 standard. primary outcomes included aerosol penetrance as well as the pressure drop across the filter material. halyard h600 failed to meet niosh n95 standards. the halyard h600 demonstrated pressure differences of 37.4 and 67.8mm h2o across single and double layered material, respectively, representing values higher than the niosh maximal resistance criteria of 35 mm h2o ( figure 2 ). 2 niosh mandates a 95% filtration efficacy (efficacy = 1penetrance) of a 0.3 µm aerodynamic mass median diameter particle for n95 certification. the halyard h600 demonstrated high penetrance at both single and double layered testing resulting in efficacy rates of 64.5% and 78.3%, respectively. objective data on halyard h600's ability to safely filter viral particulate is lacking, as is data regarding the breathing resistance of the material. numerous claims report the halyard h600 has a 99% filtration rate suggesting it is more effective than the standard n95 mask. [3] [4] this statement, however, remains misleading with the potential for unsafe interpretation as this filtration rating stems from the material's bacterial filtration efficacy (bfe). the bfe test utilizes aerosolized staphylococcus aureus, which has a documented mean particulate size of 3 ±0.3 µm, in order to assess a material's resistance to bacterial penetration. 5 current n95 standards require that respirators prohibit at least 95% of very small (0.3 µm via aerodynamic mass median diameter) particulate through their barrier for which the halyard h600 did not achieve. 2 as such, these findings suggest that bfe data cannot be extrapolated to n95 standards, nor should it be applied to viral particulate. equally as important, the halyard h600 did not meet current standards for resistance across the filtration membranes suggesting decreased breathability and the potential for unsafe levels of exhaled carbon dioxide retention. this increased resistance may further cause over pressurization at the mask-skin interface resulting in air leaks at the seal posing potential health risks due to an improper fit. finally, it is important to note that o&m halyard, the wrap's manufacturer, does not endorse the off-label use of its instrument wrap for homemade respirator masks. 6 to our knowledge these results are the first to assess the safety and efficacy of the halyard h600 instrument wrap as a respiratory mask alternative for the covid-19 pandemic. in doing so, we demonstrated that the current claims suggesting superior filtration results when compared to medical-grade n95 masks were derived from an incorrect interpretation of industry-grade testing. although these novel alternatives may demonstrate some potential as a last hope option in scenarios lacking medical-grade respirators, this data suggests they should be utilized during times of complete necessity and with an abundance of caution. as such, novel alternatives should continue to be sought; however, it remains critically important they are subjected to objective industry standards in order to provide the most accurate safety data available. niosh certification test standards (42 cfr part 84)  a sodium chloride (for n-series filters) or a dioctyl phthalate oil (for r-and pseries filters) test aerosol with a mass median aerodynamic diameter particle of about 0.3 µm, which is in the mpps-range for most filters  airflow rate of 85 l/min, which represents a moderately-high work rate  conditioning at 85% relative humidity and 38°c for 24 hours prior to testing  an initial breathing resistance (resistance to airflow) not exceeding 35 mm water column* height pressure and initial exhalation resistance not exceeding 25 mm water column height pressure  a charge-neutralized aerosol  aerosol loading conducted to a minimum of 200 mg, which represents a very high workplace exposure  the filter efficiency cannot fall below the certification class level at any time during the niosh certification tests figure 2 ) current niosh certification standards. 2 industrial safety & hygiene news sterile wrap fashioned into masks. healthcare packaging n95 mask production ramping up, but you have options if you're crafty and in a hurry f2101-01: standard test method for evaluating the bacterial filtration efficiency (bfe) of medical face mask materials, using a biological aerosol of staphylococcus aereus covid 19 ppe frequently asked questions. halyard: part of the owens & minor family. accessed the authors would like to thank the support of the us army combat capabilities development command chemical biological center for their support and guidance with filtration testing. this work was not supported by any grant funding key: cord-325598-gy809ee0 authors: lyne, cloutier; natacha, merindol; geneviève, pépin; caroline, marcoux-huard; pier-alexandre, vasil; claudia, houle; shweta, todkar; marie-claude, lehoux; nathalie, houle; hugo, germain; alexis, danylo title: asymptomatic carriers of covid-19 in a confined adult community population in quebec: a cross-sectional study date: 2020-08-21 journal: am j infect control doi: 10.1016/j.ajic.2020.08.015 sha: doc_id: 325598 cord_uid: gy809ee0 several countries have undertaken social distancing measures to stop sars-cov-2’ spread. asymptomatic carriers’ prevalence is unknown and would provide essential information on hidden viral circulation. in our cross-sectional study, 1.82% of 330 asymptomatic confined individuals living in the community carried sars-cov-2 despite no contact with declared cases, raising concerns about unnoticed transmission. cloutier, lyne 1 ; merindol, natacha 2,3 ; pépin, geneviève 4 ; marcoux-huard, caroline 5 ; vasil, pier-alexandre 5 ; houle, claudia 6, 7 ; todkar, shweta 1 ; lehoux, marie-claude 3 ; houle, nathalie 1 ; germain, hugo 2,3 ; danylo, alexis 6  sars-cov-2 may spread asymptomatically in a population under social distancing restrictions. as of august 9 th , nearly 20 million individuals contracted covid-19 and about 720,000 died [1] . the united states counts for one fourth of these cases. sars-cov-2 transmission occurs principally through respiratory droplets or direct contact [2] . viral load peaks before or at the time of symptoms onset, raising the possibility that presymptomatic people significantly contribute to viral spread [3, 4] . other individuals remain asymptomatic despite viral detection, suggesting that they may participate in transmission [5] [6] [7] . studies conducted on individuals from the same households have convincingly shown that pre-symptomatic or asymptomatic sars-cov-2 carriers might transmit to their family members [8] [9] [10] . in a long-term care facility, 23 (30.3%) residents carried the virus, including 13 asymptomatic of the 76 that were tested [11] . an investigation on the diamond princess cruise ship in japan identified 17.9% of sars-cov-2 infected cases as asymptomatic [12] . all these reports were carried out in a specific context of strong contacts between individuals. very few studies have assessed the proportion of asymptomatic individuals in the reality of a community that followed social distancing measures. in an isolated city of italy, screening three thousand individuals lead to the identification of 88 carriers, including 50-75% of asymptomatic individuals [13, 14] . nishiura our cross-sectional study was held between april 14 th and 17 th , 2020 in the mauricie region, québec, canada. we aimed to identify the proportion of asymptomatic carriers in a confined community of adults. the term confinement is used herein to reflect social restrictions instructed by quebec's government, progressively implemented starting on march 11 th (figure 1 ). on april 17 th , the last day of this study, 723 positive cases were identified for a total of 17,521 with a prevalence of 0.204% and an incidence of 0.008% in the quebec's province. a total of 2250 employees between 18 and 69 years old from the université du québec table 1 ). we (table 1 ). our study identified 1,82% of asymptomatic carriers in a confined community. their presence could be explained by 3 scenarios. first, they could be in fact presymptomatic individuals, as viral load peaks at the time of, or before symptoms onset [12, 19] . our study was not designed to assess this possibility if symptoms developed later than 24 hours post-test. second, following symptomatic infection, some cases experience prolonged viral nucleic acids detection by rrt-pcr [20] . consequently, some individuals could be post-symptomatic cases with residual viral shedding that were not screened at the beginning of the pandemic. the third possibility is true asymptomatic infection. the rate of this kind of infection is unknown. pre-symptomatic people significantly contribute to viral spread, but we do not know if true asymptomatic and late post-symptomatic participate in transmission at this point. all positive cases had high c t values, which most probably reflects low viral shedding, although data are sparse on correlation between c t values and contagiousness. 1,82% of asymptomatic carriers is high when compared to the 0,204% prevalence. however, there were 18.03% of carriers among the thousands of screened symptomatic individuals in the province, ten times more than in our asymptomatic cohort. our sample size is relatively small. at the time we designed our study, supplies in lab materials and staff availability were problematic, we chose a convenience sample size. rates of asymptomatic carriers could be different in high-density urban area and in population with different socio-economic characteristics. despite its limitations, this is the first methodically designed study that evaluates the rate of asymptomatic carriers in a confined population. six sars-cov-2 asymptomatic carriers that agreed with social distancing measures is a significant number and could suggest that prevalence is underestimated. this could represent ~100,000 asymptomatic carriers at the scale of the adult population of quebec's province at the time of this study. interestingly, a preliminary analysis of the seroprevalence on 7,691 blood donors from québec reported a similar rate of positivity [21] . our results raise concerns about the possibility of viral spread through asymptomatic transmission, specifically in the context of an apprehended resurgence of sars-cov-2 infections following deconfinement. since public health focuses on symptomatic cases, it is urgent to determine if asymptomatic cases contribute to transmission and to elucidate the dynamics of sars-cov-2 in distinct populations. seegene graciously offered lab test kits. the company was not involved in the study design nor in the data analysis. internal research funds from uqtr. no external funding legend: in the province of quebec, the first case was declared on february 27 th . on march 11 th , travelers were isolated at home for 14 days upon return, gathering of more than 250 people were forbidden. on march 13 th , the health emergency state was declared. on march 14 th , non-essential visits to hospitals and long-term care facilities were prohibited. between march 15 th and april 5 th , borders, public places, daycares, schools, businesses, non-essential services were closed, social distancing measures were implemented, gatherings of more than 5 individuals and travels between regions were prohibited. this study was conducted between april 14 th (612 positive cases on that day for a total of 14 860, a prevalence of 0,173% and an incidence of 0,007%) to april 17 th (723 positive cases for a total of 17521; a prevalence of 0,204% and an incidence of 0,008%) (data has been extracted from public health resources [22] ). graphical abstract. asymptomatic frequency estimate during lockdown. * according to public data during the time of the study. legend: attitudes towards measures of social distancing and confinement were analysed through a likert scale ranging from 1 to 7; 1 being complete agreement. results presented in table 1 show that very little variation in the scores, e.g. all participants being very much in agreement with the measures issued by the government during the two periods. the vast majority also stated that they were abiding by those rules. all differences noted between groups and within groups were not statistically significant. coronavirus disease 2019 aerosol and surface stability of sars-cov-2 as compared with sars-cov-1. the new england journal of medicine temporal dynamics in viral shedding and transmissibility of covid-19 potential presymptomatic transmission of sars-cov-2 asymptomatic carrier state, acute respiratory disease, and pneumonia due to severe acute respiratory syndrome coronavirus 2 (sars-cov-2): facts and myths presumed asymptomatic carrier transmission of covid-19 transmission of 2019-ncov infection from an asymptomatic contact in germany transmission potential of asymptomatic and paucisymptomatic sars-cov-2 infections: a three-family cluster study in china. the journal of infectious diseases asymptomatic and human-to-human transmission of sars-cov-2 in a 2-family cluster delivery of infection from asymptomatic carriers of covid-19 in a familial cluster asymptomatic and presymptomatic sars-cov-2 infections in residents of a long-term care skilled nursing facility estimating the asymptomatic proportion of coronavirus disease 2019 (covid-19) cases on board the diamond princess cruise ship dobbiamo cambiare rotta, tampone a chi non ha sintomi covid-19: identifying and isolating asymptomatic people helped eliminate virus in italian village international journal of infectious diseases, 2020. 16. institut national de santé publique du québec. données covid-19 au québec sars-cov-2 detection by direct rrt-pcr without rna extraction dépistage à l'uqtr: un nombre très faible de porteurs asymptomatiques familial cluster of covid-19 infection from an asymptomatic prolonged presence of sars-cov-2 viral rna in faecal samples. the lancet: gastroenterology & hepatology étude de séroprévalence des donneurs de sang: 2,23% de la population adulter du québec aurait contracté la covid-19 the research team wishes to acknowledge the université du québec à trois-rivières (uqtr) for providing human, financial and structural resources for the project and the centre intégré universitaire de santé et de services sociaux de la mauricie et du centre-du-québec (ciusss mcq) for providing testing resources. we also thank participants and all volunteer nurses and personnel that worked at the clinic. key: cord-340051-r9kn34wd authors: mei, xue; zhang, yuyi; zhu, hui; ling, yun; zou, ying; zhang, zhengguo; guo, hongying; liu, yu; cheng, xingxia; liu, min; huang, wei; wang, jiefei; yi, zhigang; qian, zhiping; lu, hongzhou title: observations about symptomatic and asymptomatic infections of 494 patients with covid-19 in shanghai,china date: 2020-07-06 journal: am j infect control doi: 10.1016/j.ajic.2020.06.221 sha: doc_id: 340051 cord_uid: r9kn34wd background: humans are generally susceptible to sars-cov-2, which has caused a global pandemic of covid-19. the screening of infected people in the population still mainly depends on clinical symptoms. however, there is limited research on the characteristics of clinical symptoms in different populations, especially in imported cases. methods: to retrospectively analyze the clinical data of 494 confirmed covid-19 patients admitted to a designated hospital in shanghai from january 20, 2020, to march 31, 2020, we compared the clinical manifestations in different populations and their influencing factors in covid-19 patients. results: (1) of the 494 patients, 453 (91.7%) had different symptoms at admission, and 39 (7.89%) patients were asymptomatic. (2) we compared the symptoms of patients according to different stratifications and found the following results: a. the proportion of dyspnea was significantly higher in male patients than in female patients (p < 0.05). b. the proportions of a stuffy nose, sore throat, and olfactory and gustatory dysfunction were significantly higher in children than in adult patients (p < 0.05). c. the proportions of fever, chest tightness, shortness of breath, and fatigue were significantly higher in local cases than in imported cases. in comparison, the proportions of nasal congestion, stuffy nose, sore throat, headache, and olfactory and gustatory dysfunction were significantly lower in imported cases than in imported cases (p < 0.05). d. the proportions of chest tightness, shortness of breath, and dyspnea were significantly higher in severely ill patients than in those with mild symptoms (p < 0.05). (3) thirty-one asymptomatic patients were significantly younger than symptomatic patients, and they had a higher proportion of imported cases, white blood cell (wbc) and lymphocyte (lym) count levels, and fewer abnormal ct cases than the group of symptomatic patients (p < 0.05). (4) the number of days since the onset of the disease needed for the symptoms to disappear was associated with the epidemiological history (imported cases), the number of days until the pharyngeal swab nucleic acid test turned negative, the days of hospitalization, the days of onset, and the wbc and lym count levels (p < 0.05). conclusion: the majority of covid-19 patients (91.7%) had early symptoms. whereas 7.89% of covid-19 patients were asymptomatic. younger patients had fewer symptoms, mainly the upper respiratory symptoms, and the illness condition was milder, which was more common in imported cases. elderly male patients had severe symptoms when admitted. the number of days needed for the patient's symptoms to disappear was closely related to the number of days necessary for the pharyngeal swab nucleic acid test to turn negative. due to the highly contagious sars-cov-2 and the susceptibility of the population, the rapid spread of the covid-19 epidemic has caused an ongoing global pandemic, and many countries declared a national emergency 1 . until may 6, the cumulative number of diagnoses was 3,638,437, and the cumulative number of deaths was 256,958 2 . the mortality rate in several countries exceeded 10%, which brought substantial economic losses and life threats to people around the world. at present, the diagnosis of covid-19 depends on nucleic acid testing 3 . however, due to the rapid increase in the number of infections, the high cost of nucleic acid testing, and the shortage of medical supplies, nucleic acid testing cannot be entirely popularized. many countries have taken measures to monitor the temperature to screen suspected patients for investigation and isolation. however, recent studies have found that the clinical manifestations of some patients with covid-19 are not typical, and many asymptomatic infections have been reported 46 . international studies have found that asymptomatic infections may account for about 60% of all infections, and there are robust viral replication in these patient's throat swab and the virus is highly infectious4, which has brought challenges to the control of outbreaks worldwide. therefore, it is urgent to fully understand the clinical symptoms of patients with covid-19 in different populations and its influencing factors, but the relevant reports are scarce. by summarizing and comparing the symptoms characteristics and its influencing factors of covid-19 patients in shanghai, china, this study may provide a theoretical basis for first-line quarantine personnel and clinicians to screen suspected patients. we conducted a retrospective study on patients with covid-19 from january 20, 2020, to march 31, 2020, in the ***. the patients were diagnosed according to the chinese management guideline for covid-19 guidance by the national health committee (version 7.0) (hereinafter referred to as "guideline") 7 . all of the confirmed cases of covid-19 were defined as a positive real-time rt-pcr assay result using pharyngeal swab specimens 8 . only laboratory-confirmed cases were included in the analysis. according to the classification criteria referred in the "guideline," 30 patients were clinically classified as severely and critically ill patients, and 464 patients were clinically classified as mild and ordinary patients. two attending physicians reviewed the electronic medical records of all patients and collected relevant epidemiological investigation, demographic data, medical history, symptoms, laboratory examination results, and chest ct scan reports. routine blood test results were collected, including white blood cell (wbc) and lymphocyte (lym) counts. the biological safety protection third-level laboratory of shanghai public health clinical center was approved by the chinese center for disease control and prevention (cdc). according to who guidelines on qrt-pcr, pharyngeal swab samples were collected and tested for sars-cov-2 rna. to exclude as far as possible the interference of the relevant treatment after admission, early clinical symptoms were defined as all of the clinical symptoms that occur within three days after the diagnosis of the pharyngeal swab nucleic acid test. for patients who were asymptomatic at admission, we observed symptoms during the entire hospitalization process. the observation time for olfactory and gustatory dysfunction was from the onset to discharge. this study screened out asymptomatic infections from close clinical and community contacts and imported cases from outbreak areas. asymptomatic cases with covid-19 were defined as asymptomatic cases with a positive nucleic acid test. fever was defined as an axillary temperature of at least 37.3°c. respiratory symptoms included cough, runny nose, sore pharyngeal, sore pharyngeal, chest tightness, chest pain, shortness of breath, and dyspnea. gastrointestinal symptoms included abdominal distension, diarrhea, anorexia, nausea, and vomiting, among others. systemic symptoms were defined as fatigue, dizziness, headache, muscle aches, arthralgia, and other symptoms. the days of onset were defined as the time interval from the onset of symptoms to admission to our hospital. the number of days needed for the pharyngeal swab nucleic acid test to turn negative was defined as the time interval from the first symptoms to the day the nucleic acid test first turned negative. the days needed for the pharyngeal swab nucleic acid test to become negative in the asymptomatic patients were defined as the time interval from the first positive nucleic acid test to the first negative nucleic acid test. the days until the patient's symptoms disappeared were defined as the time interval from the patient's first symptoms to their disappearance. the discharged patient had to conform to the following conditions 6 : (1) the patient' temperature returned to normal for more than three days; (2) respiratory symptoms improved significantly; lung imaging showed a significant improvement in acute exudative lesions; (3) the rt-pcr test of pharyngeal swab samples had two consecutive negative results (at least 24 hours apart), and we recorded the earliest date the nucleic acid test turned negative. this study was approved by the *** ethics committee, fudan university. written informed consent was waived in light of the urgent need to collect new infectious disease data. for continuous variables, first, a distribution of data test was conducted. the normally distributed data were expressed as mean ± standard deviation (χ ± s). the t-test was used for the comparison of differences between groups. the non-normally distributed continuous variables were expressed as medians (interquartile range), and differences between groups were compared by the mann-whitney test. categorical variables were expressed in terms of frequency or rate, and the differences between groups were compared by the χ2 test or fisher's exact test. to explore the factors associated with the period during which the symptoms were observed, the spearman correlation analysis was used. if the p-value of the test result was <0.05, the difference was considered to be statistically significant. all of the research data were described and analyzed using spss 25.0 statistical software. of the 494 patients with covid-19, 266 were male (53.8%), the age range was 6-88 years old, and the median age was 40 years old. there were 30 critically ill patients with a critical illness rate of 6.07%, and seven deaths with a mortality rate of days of hospitalization** 16 12-21 days needed for the pharyngeal swab nucleic acid turned negative*** *days of onset = date of admission-date of early symptom, asymptomatic cases were not included **days of hospitalization = date of discharge-date of admission, deaths cases were not included ***days needed for pharyngeal swab nucleic acid turned negative = first date of pharyngeal swab nucleic acid turned negativefirst date of early symptom, and days needed for asymptomatic infected patient's nucleic acid turned negative = date of pharyngeal swab nucleic acid turned negativedate of diagnosis, death cases were not included. of the 494 patients, 453 had symptoms (91.7%) at admission, and 39 (7.89%) patients had no symptoms at admission. of these, 31 (6.28%) were asymptomatic throughout hospitalization and eight (1.62%) patients were asymptomatic on admission, but with symptoms during hospitalization. 203 patients (44.81%) had three or more symptoms. all of the symptoms included respiratory symptoms, fever, gastrointestinal symptoms, olfactory and gustatory dysfunction, rashes, and systemic symptoms (see figure 1 ). we compared the symptoms of patients between the groups according to different stratification and found the following results: the proportion of dyspnea was significantly higher in males than in females. the young-age group had the fewest number of symptoms and the lowest rate of fever. still, the incidence of nasal congestion, sore pharyngeal, olfactory, and gustatory dysfunction in the young-age group was significantly higher than in elderly patients. elderly patients had the highest proportion of symptoms, such as fever, dyspnea, fatigue, and anorexia, but no olfactory and gustatory dysfunction. local cases had more fever, chest tightness, shortness of breath, and fatigue symptoms than imported cases. at the same time, the frequencies of nasal congestion, runny nose, sore pharyngeal, headache, and olfactory and gustatory dysfunction were significantly lower than those in imported cases, and the differences were statistically significant. the proportions of symptoms of chest tightness, shortness of breath, and dyspnea were significantly higher in the severely ill group than in the mild group, and the remaining symptoms were not statistically significant (see figure 2 ). asymptomatic infections were significantly more frequent in younger patients than in elderly patients. the proportion of imported cases and both wbc and lym count levels in the symptomatic patients were higher than in the symptomatic patients. the abnormal ct cases in the asymptomatic infections were fewer than those in symptomatic infections. the differences were statistically significant. however, there was no statistically significant difference in gender, the days needed for the pharyngeal swab nucleic acid test to turn negative after admission, and the days of hospitalization. eight patients were asymptomatic in the early stage, but cough and fever symptoms appeared after admission. among them, four patients had symptoms after the nucleic acid test turned negative, three patients had symptoms before the nucleic acid test turned negative, and one patient had symptoms on the day when the nucleic acid test turned negative (see tables 2 and 3 ). among the patients with covid-19, there were 168 (34%) patients with positive nucleic acid test after the symptoms disappeared, and it took more days for the pharyngeal swab nucleic acid test to turn negative in these patients than in those with a negative nucleic acid test after the symptoms disappeared (see table 4 ). the days until the symptoms disappeared in patients with covid-19 were positively correlated with the history of epidemiology (imported cases),the days needed for the pharyngeal swab nucleic acid test to turn negative, and the days of hospitalization. it was negatively correlated with days of onset, wbc count level, and lym count level (see table 5 ). we analyzed the clinical characteristics of 494 patients with covid-19 in shanghai and found that covid-19 patients were mostly adults, up to 94.94%, and children and adolescent cases were rare (5.06%). similar to previous research results 9,10 , children did not seem to be susceptible, or their symptoms were relatively mild, and they cannot easily catch the infection. however, there was no significant difference in the sex ratio. most of the patients with covid-19 in shanghai area visited the hospital earlier, and the median period of onset was only four days. the critical illness rate was 6.07%, which also confirmed that the early intervention of covid-19 was essential for reducing critical illness and mortality rates in many epidemic areas. our study also showed that the median periods until the pharyngeal swab nucleic acid test turned negative and to end hospitalization were about two weeks, which indirectly confirmed that 14 days of observation in isolation for suspected patients is necessary; even asymptomatic patients could clean the virus within two weeks. the longest period required for the pharyngeal swab nucleic acid test to turn negative was 18 days in asymptomatic patients, and only 12.9% (4/31) cases were over 14 days. the median of the wbc count level and the lym count were within the normal reference range, and no obvious bacterial infection was seen. eighty-four percent of patients (415/494) had abnormal ct manifestations. still, some of these patients had no symptoms, which seems to suggest that patients with abnormal ct manifestations also need to be tested for the sars-cov-2 infection, even if the patient has no fever or respiratory symptoms. although covid-19 is a respiratory infection disease, the early symptoms of patients were not limited to respiratory symptoms and fever. in fact, 21.05% of patients could show gastrointestinal symptoms in the early stage, some patients had viremia-related symptoms, such as headache, dizziness, muscle aches, arthralgia, and fatigue, and 7.89% of patients had olfactory and gustatory dysfunctions. unlike the findings of a multicenter european study 11 , 85.6% and 88.0% of patients had olfactory and gustatory dysfunctions, respectively, and this difference may be related to genetic background of the populations tested. in addition, it was interesting to observe that three patients (0.61%) had rashes in the early stage of the disease. it is well known that people with viral infections, such as measles and chickenpox, usually present with fever and rashes, but there have been no reports of covid-19 patients with rashes in the early stage. however, we cannot rule out the effects of early medication on these patients with rashes, and further observation is needed in the future. the proportion of severely ill patients was higher in males, and male patients had a higher proportion of symptoms of dyspnea. our data also reflected to a certain extent that children with covid-19 often presented with upper respiratory tract symptoms, and the illness condition was often mild. the proportion of elderly people with dyspnea was higher, which is related to the fact that advanced age was likely to cause severe disease. imported cases in shanghai, which is an international city, had increased significantly since march, and their age was significantly lower than that of local patients, the time of confirmed disease was earlier, and the condition was milder. these patients had mainly upper respiratory tract symptoms such as nasal congestion, sore pharyngeal, headache, and abnormal olfactory and gustatory functions. except for most symptomatic infected patients, the proportion of asymptomatic infections was not high, almost 7.9%, and they were younger and mostly imported cases. we also found that the levels of wbc count and lym count in the asymptomatic infections were significantly higher than in the symptomatic patients, this research had some limitations. first, our study was only a retrospective analysis of a single center in shanghai. a small proportion of symptoms may be subjective to the patient, and second, asymptomatic infections were mostly imported cases and, due to the pandemic in the world, its epidemiological history outside the country was not clear, and it was impossible to determine the real time of infection. in summary, from the analysis of this group of patients with covid-19 in shanghai, we conclude that young patients have more common upper respiratory symptoms after infection, and the prognosis is good. furthermore, the proportion of early asymptomatic patients is not high (not more than 10%), and it is more common in young patients and imported cases. the days until the symptoms disappeared in patients with covid-19 patient were positively correlated with the days needed for the pharyngeal swab nucleic acid test turned negative, but negatively correlated with the wbc count and lym. the symptoms of the imported cases disappeared faster, and the illness condition was milder. for young people and entryexit personnel, nucleic acid detection is required as a measure to exclude infected patients. during the outbreak of the epidemic, we consider that 14 days of isolated observation may be necessary for people with a history of epidemiology. is sars-cov-2 also an enteric pathogen with potential fecal-oral transmission: a covid-19 online ahead of print clinical features of patients infected with 2019 novel coronavirus in wuhan, china covert coronavirus infections could be seeding new outbreaks epidemiology of covid-19 among children in china clinical characteristics of 24 asymptomatic infections with covid-19 screened among close contacts in nanjing, china,sci china life sci national health commission of the people's republic of china. chinese management guideline for covid-19 clinical characteristics of novel coronavirus cases in tertiary hospitals in hubei province the novel coronavirus pneumonia emergency response epidemiology team. the epidemiological characteristics of an outbreak of 2019 novel coronavirus diseases (covid-19) in china epidemiological and clinical features of the 2019 novel coronavirus outbreak in china olfactory and gustatory dysfunctions as a clinical presentation of mild-to-moderate forms of the coronavirus disease (covid-19): a multicenter european study positive rt-pcr test results in patients recovered from covid-19 sars-cov-2-positive sputum and feces after conversion of pharyngeal samples in patients with covid-19 this study was supported by top university and first-class discipline construction project of fudan university (project no: idf162005); scientific research project for novel coronavirus "2019-ncov" of ** (project no:2020yjky01). we thank letpub (www.letpub.com) for its linguistic assistance during the preparation of this manuscript. all of the authors participated in the research design. **, **, and ** had the idea for this study, designed it, and had full access to all of the data. **, **, and ** performed the data management and statistical analyses after discussion with all authors. all of the authors participated in data interpretation and in writing the manuscript. all of the authors took responsibility for the decision to submit for publication. the authors declare that there is no conflict of interests. key: cord-345210-6f8niif5 authors: tadavarthy, silpa n.; finnegan, kerriann; bernatowicz, gretchen; lowe, elisha; coffin, susan e; manning, marylou title: developing and implementing an infection prevention and control program for a covid-19 alternative care site in philadelphia, pa date: 2020-07-19 journal: am j infect control doi: 10.1016/j.ajic.2020.07.006 sha: doc_id: 345210 cord_uid: 6f8niif5 background: on march 27, 2020, the city of philadelphia was given permission by temple university to convert the liacouras center gymnasium to an alternate care site (acs) to treat low-acuity covid-19 patients. acs's, especially those created to specifically care for infectious patients, require a robust infection prevention and control (ipc) program. methods: the ipc program was led by a physician and nurse partnership, both of whom had substantial experience developing ipc programs in u.s. and low-resource settings. the ipc program was framed on a previously described conceptual model commonly referred to as the “4s's”: space, staff, stuff, and systems. results: the gymnasium was transformed into red, yellow and green infection hazard zones. the ipc team trained 425 staff in critical ipc practices and personal protective equipment (ppe) standards. systems to detect staff illness were created and over 3550 staff health screening surveys completed. discussion: use of existing guidance and comprehensive facility and patient management assessments guided the development of the ipc program. program priorities were to keep staff and patients safe and implement procedures to judiciously use limited resources that affect infection transmission. conclusion: planning, executing and evaluating ipc standards and requirements of an acs during a pandemic requires creative and nimble strategies to adapt, substitute, conserve, reuse, and reallocate ipc space, staff, stuff and systems. on january 21, 2020, the first case of laboratory-confirmed infection due to the novel virus severe acute respiratory syndrome coronavirus 2 (sars-cov-2) in the united states was identified in seattle, washington. six weeks later, in early march, the first person in pennsylvania was diagnosed with coronavirus disease-19 (covid-19) disease. the subsequent rapid growth in covid-19 cases in the philadelphia region led most acute care hospitals to suspend non-urgent procedures and hospitalizations by mid-march. very quickly, hospitals were required to assess their surge capacity in preparation for a possible largescale, public health emergency. 1 despite individual facilities' efforts to accommodate a surge in patients with moderate-to-severe covid-19, multiple acute care hospitals in philadelphia began to experience a surge in demand just three weeks after the first confirmed case was identified. on march 27, temple university granted the city of philadelphia permission to use the liacouras center as an overflow medical facility for low-acuity covid-19 patients. 2 setting: philadelphia is the sixth largest city in the u.s. with a population of over 1.5 million people. it is also the poorest large city in the country. most hospital beds are in facilities that are members of extensive healthcare networks. according to 2018 data, philadelphia county has approximately 5,320 adult staffed medical-surgical beds and 940 intensive care unit (icu) beds, 3 although pandemic planning included identifying additional hospital beds in each facility in the event of a surge of demand. 4 the temple university liacouras center is known as a premiere basketball facility and provides a unique and flexible space, which is also used for concerts, banquets and trade shows. it is one of the largest indoor, public assembly venues in philadelphia. the initial material assets of the csf-l were provided by fema. key materials included: cots, commodes, walkers, bathing equipment, medical monitoring equipment, portable non-plumbed sinks, sharps containers, infectious waste receptacles, alcohol-based hand rub, and personal protective equipment (ppe). method: we utilized a previously described conceptual model to assess disaster responses and surge capacity, commonly referred to as the -4s's‖: space, staff, stuff, and systems. [5] [6] [7] this framework guided our development of a novel ipc program for this surge facility. in this article, we describe the -4s's‖ of our program developed for the csf-l and the related challenges at a covid-19 alternative care site. the rapid creation and unusual configuration of this facility, together with the challenges of new clinical teams unfamiliar with one another, and working together in uncomfortable ppe to provide high-quality patient care, necessitated some basic approaches to the development of our ipc program. these included: 1. use of existing guidelines and other resources from expert groups whenever available 8, 9 2. adapt existing guidance to apply to the unique conditions of the surge field hospital 3. standardize ipc processes to ensure the safety of patients and staff because the liacouras center was neither designed nor engineered to care for patients, a comprehensive environmental and occupational risk assessment was undertaken prior to facility opening. environmental health and safety experts, together with leaders of the ipc team, conducted an -all-hazard‖ risk assessment of the site for actual or potential risks to patients or staff; this team produced a comprehensive health and safety plan for the csf-l. the plan identified the need for engineering controls (e.g. specifications for heating, ventilation, and air conditioning systems) and specified occupational ipc health and safety requirements, including ppe standards, daily monitoring of staff for acute illness, sanitation standards for both hand hygiene and equipment sanitation, as well as laundry and waste management recommendations. the identified ipc hazards and risk reduction plans, priorities and progress were reported and addressed by the csf-l team before the facility moved forward in development. a facility map was created that designated -red, yellow, and green zones,‖ each with a different level of infection risk and expectation for ipc practices and ppe use. colored tape was placed on the floor to provide visual cues. separate entrance and exit paths were designated for both staff and patients. the patient care and decontamination areas were designated as -red zone‖, requiring the highest level of ppe and to which physical access was strictly controlled. the -green zone‖ included the facility entrance and hallways leading to the staff locker room; only surgical masks were required while in these areas. the -yellow zone‖ was the interface between -red zone‖ and -green zone‖ where staff donned and doffed ppe. nearby liacouras offices were converted into ppe storage and distribution rooms. the ipc team was led by a member of the pdph's healthcare-associated infections and antimicrobial resistance team (sec) and a highly experienced nurse certified in ipc (mlm). collectively, these coleaders have over 50 years of experience serving as local, national and international consultants and trainers for ipc programs. additional critical ipc team members included temple university medical students (st and kf), a nurse practitioner experienced in family medicine and college health and a registered nurse experienced in ipc (gb and el). our team worked in concert with the pdph and oem staff onsite as well as the csf-l leadership team. given the unique setting, heterogenous background of staff and challenges preventing nosocomial transmission of the sars-cov-2 virus and other potential healthcare associated infections, infection preventionist (ip) coverage of the -red zone‖ on all shifts was considered an integral component of the ipc plan. a call for volunteers from the local chapter of the association for professionals in infection control and epidemiology (apic) was released via the chapter listserv. interested and available ips were instructed to register through the philadelphia mrc website. however, recruiting these ips was a lofty goal given the intense increase of ip workload in their own facilities, so we began to seek ip designees, such as nurses or public health experts with advanced ipc knowledge. 10 monitor. it was important to have a core group of individuals assigned to these roles as their responsibilities included being familiar with policies and providing focused coaching to ensure staff adherence to essential infection prevention practices. the fema medical station cache provided resources for a 250-bed facility. the included ipc resources included 1,070 n95 respirators of various sizes and models, 3 fit test kits, 900 surgical masks, 300 disposable isolation gowns, 192 face shields, and over 100 boxes of non-sterile examination gloves of various sizes. the cache also included 5 portable, non-plumbed sinks and alcohol-based hand rub. additional ppe resources were continuously being sought and obtained through vendors as well as private and public donations. the availability and maintenance of the ppe inventory was critical for csf-l operation. prior to opening, a baseline inventory of every item was established and the ppe distribution room was organized to maximize space and to improve the efficiency of distribution. it was staffed 24 hours per day by a consistent group of registered nurses and two members of the dod to standardize the process. all staff entering the patient care area (-red zone‖) received an isolation gown, a face shield, and a fit-tested n95 respirator from the ppe distributor. their name and the items they received were recorded by hand in the ppe distribution log. this process was repeated each time the staff member entered the patient care area at the start of their shift and after each scheduled break. staff received a new or reprocessed n95 respirator each time they entered or re-entered the -red zone.‖ a running count of all items distributed was recorded every six hours on the daily ppe inventory tracking form. stock delivered to the ppe distribution room and items returned to stock after reprocessing were also recorded here. the numbers from the previous 24 hours were reconciled at the start of each day and entered by hand into the master inventory spreadsheet. key process indicator reports outlining the number of days on hand of each item were generated daily and shared with the leadership team. all ppe, except gloves and surgical masks, was reprocessed. face shields, safety glasses and goggles were disinfected on site by the decontamination staff in a designated, well-ventilated area away from patient care and all other activities, with a hospital-grade disinfectant. n95 respirators were reprocessed using a bioquell hydrogen peroxide vapor decontamination facility developed by a local hospital to maintain their own ppe supply. the used n95 respirators were prepared and packaged for transport by the waste management staff and were transported to and from the reprocessing facility every other day. isolation gowns were reprocessed daily by a medical laundry service. all reprocessed items were then returned to the ppe distribution room and logged into the inventory tracking form. one point of entry into csf-l was established for all staff to ensure security and facilitate health screening. this area was staffed 24 hours per day by security personnel and a staff entrance surveillance monitor. staff entering the building were required to wear a personal face mask and remain six feet apart from other personnel at all times; if someone did not have a mask, a surgical mask was provided. surveillance was intended to identify individuals with clinical signs or symptoms suggestive of covid-19 or other acute illness, or recent exposure to sars-cov-2. the daily entrance survey was accessed and completed by volunteers and staff using a qr (quick response) code on their smartphone or if they had no smartphone, on a paper survey. staff monitors verified that the survey was complete, asked about any positive answers and took each volunteer's temperature using a no-contact infrared thermometer. the names of all individuals who reported symptoms of an acute illness or a temperature >100.4°f were recorded for investigation; ill staff were instructed to return home and given instructions for self-monitoring and when to seek care. staff who cleared the screening process signed in, performed hand hygiene using an alcohol-based hand rub, and proceeded into the facility. staff entrance screening began on april 10 and responses were monitored daily through may 7. during that time period approximately 3,550 surveys were completed. no staff were noted to have a fever upon temperature check or a positive symptom screen at facility entry. staff were recruited from the philadelphia mrc (a group who serve the city during public health emergencies and large-scale events), contracted staffing agencies and vendors, and the dod. this meant clinical staff came with varying experiences and approaches to infection control and nonclinical/support staff had little to no experience with ipc measures. we operated under the assumption that all staff needed training in csf-l-specific ipc standards and measures. thus, we developed orientation materials and training procedures in order to ensure that staff would be adequately protected and trained. we created an -infection prevention and control orientation‖ presentation that described proper protocols for entering the csf-l with the screening survey, hand hygiene, ppe standards and processes, mask use and reuse, cleaning and disinfection, sharps safety and occupational exposures, including needlesticks. this presentation also included videos from the cdc demonstrating proper donning and doffing technique. the ipc presentation and live ppe demonstration took approximately 30 minutes and was included with other ori-entation presentations on the facility and its mission, safety measures and a tour of the patient care area. after completion of the orientation, clinical staff were fit tested using osha respirator fit testing protocol by environmental health and safety consultants for the available n95 respirators. they were required to don and doff the ppe that would be available at csf-l with trained ipc team members assisting and observing the techniques. eleven orientation sessions were held between april 13 and april 23 and were attended by 425 staff. given the unique clinical environment, rapidity of development of ipc standards, and challenges with equipment procurement, we used a process of rapid cycle tests of change to adapt the ppe process, while remaining aligned with current cdc guidelines. during the duration of the csf-l development and use, every person on site was required to wear a face covering (either a cloth face covering or surgical mask). plastic full-face shields were the standard eye and face protection for every person working in the patient care area. safety glasses and goggles were provided as an alternate strategy for eye protection. following the ppe standards obtained from the emergency field hospital opened at the jacob k. javits convention center in new york city and the most current cdc recommendations, the ipc team initially recommended that only providers of hands-on patient care would wear n95 respirators, while non-patient care staff, such as environmental services, would wear a surgical mask. after further consideration of the open patient care environment, uncertainty of the infectivity of the patients, and goal of providing as much assurance of safety as possible to staff, we established a standard that all staff present in the patient care area (-red zone‖) would wear an n95 respirator and eye protection. because the number of disposable isolation gowns was limited, the ipc team, with support from a vendor, was able to obtain 500 reusable, fluid resistant isolation gowns for use by all staff while in the patient care area. hand hygiene with alcohol-based hand rub was required before donning gown and gloves and after doffing gloves and gown, face shield and n95 respirator. clean, intact gloves were required to be worn by all volunteers present in the patient care area. hand hygiene with alcohol-based hand rub and glove change was required between each patient contact and when moving from dirty to clean activities. although portable, non-plumbed sinks were available, they were ultimately not used in the patient care area because they had only a fivegallon reservoir of water and therefore posed more challenges than benefits including needing to be refilled and cleaned often. thus, wall mounted alcohol hand rub dispensers were placed on the headwall of each bed space and table top dispensers were available at nursing stations and other staff work areas. safety and inventory were two guiding principles used in creating quality improvement measures at the csf-l. when we experienced a 53% loss of n95 respirators during the first round of reprocessing, primarily due to makeup use, we added a strongly worded request to the orientation that all staff refrain from make-up use while in the facility. we also provided makeup removal wipes and posted reminders to not wear makeup along with our respirator loss rate in the locker room and staff lounge restrooms. after implementing these interventions, our respirator loss rate significantly decreased to <1%. due to some variability in ppe donning/doffing training received by staff during different orientation sessions (as a result of rapidly and continuously evolving cdc guidelines and best practice standards) a ppe and hand hygiene quality improvement donning/doffing evaluation tool was developed. the purpose was to assess proper donning and doffing procedures use by each staff member entering and leaving the -red zone‖ as well as correcting staff when needed. this was completed by the donning/doffing assistant and included 1) assessment of an n95 respirator seal check, 2) proper hand hygiene use during donning, 3) use of the appropriate ppe doffing sequence, 4) hand hygiene at appropriate moments during doffing sequence, and 5) verification that no ppe other than a personal mask was worn in the -yellow zone‖ and -green zone‖. when it was realized that there was confusion and concern around proper hand hygiene in the -red zone,‖ we developed a hand hygiene quality improvement evaluation tool to be completed by the red zone infection preventionist. this tool assessed the proper doffing of gloves, use of hand hygiene (alcoholbased hand rub for 20 seconds), and donning of new gloves between patients by providers. although we designed these measures with the intention to implement all of them, we were unable to do so due to the lack of further need for and closure of the csf-l. in this report, we describe the development, implementation and management of an ipc program for a covid-19 acs. key lessons learned included the need to: develop strategies to cope with real and potential shortages of critical supplies; adapt existing guidance for unique sites of care; standardize and continually assess staff use of ppe and fundamental ipc practices; and the importance of communication of ipc principles and concerns throughout the planning and management of this covid acs. a critical component of preparedness plans is surge capacity or the ability to adequately care for a significant influx of patients and be prepared for demands on supplies, personnel and physical space. 6 although much of disaster and surge capacity planning focuses on hospital-based care, the covid-19 pandemic required various buildings and structures of opportunity across the country be converted to temporary field hospitals with the goal of increasing healthcare capacity and capability as needed. 8 the liacouras center in philadelphia was such a structure and rapidly converted to function as an acs to assist regional health care facilities by providing non-acute care for adults with mildly to moderately symptomatic covid-19. the csf-l ipc team, reporting to the chief nursing officer, was quickly established. the team leaders had previously worked together, were well-versed on cdc ipc guidelines, and had extensive experience in establishing ipc programs in non-traditional and resource-limited settings nationally and internationally. this worked to the team's advantage as we quickly identified program aims and delineated priorities. the team relied on real-time, action-oriented learning using the plan-do-study-act (pdsa) cycle for testing our initiatives -by planning it, trying it, observing the results, and acting on what is learned. this approach led to quick, early successes. for instance, we quickly realized that although fema provided resources for a 250-bed facility, only 152 beds could be set-up in order to maintain at least six feet of distance between patients. another example, one of our first tasks was to establish the staff wellness check-in/surveillance procedure. working closely with our facility operations and security colleagues, a single point of building entry was identified. the ipc team explored several options for collecting volunteer screening data. based on convenience and ease of use we selected the free online qr code generator to create a code for the survey, while concurrently configuring the physical space to accommodate the related activities. we conducted multiple pdsa cycles to improve the original concept, resulting in an efficient, effective, standardized process. a similar approach was used to standardize ipc staff orientation and ppe donning and doffing competency check-offs. pdsa cycles were also used to navigate the ipc implications of the proposed system for facility access and flow of patients and for the support services of pharmacy, respiratory therapy, laboratory, patient linen and laundry, patient and staff food delivery, and waste (including medical waste and sharps) and garbage removal. predictably, the greatest challenge centered on managing ppe standards and clinical staff expectations. due to the critical shortages of ppe and alcohol-based hand rub across the country, the cdc revised its recommendations for the safe and appropriate use of ppe several times during our planning stages. this dynamic combined with the initial uncertainty of the resources available to the csf-l, made it difficult to develop ipc policies and procedures specific to this setting at the outset. there were also significant clinical staff concerns and anxieties surrounding ppe use. staff from throughout the us, varied practice settings (e.g., intensive care units, emergency departments, medical-surgical units) and without prior experience working together had to adapt to the csf-l ipc policies and procedures. having an ip or ip designee present 24 hours a day, seven days a week in the -red zone‖ was invaluable in managing staff ipc expectations. they provided real-time staff ipc adherence monitoring, education, coaching, support and csf-l updates. in addition, a frequently asked question sheet with answers and rationale to many commonly asked questions was created. it included questions such as -why are we not double gloving?‖, -why are we not using hand sanitizer on top of gloves?‖, -why are we not wearing a surgical mask over the n95 respirator?‖ two factors underscored the importance of standardizing ipc practices in the csf-l. first, the risk of exposure to covid-19 in the csf-l environment was possibly increased as com-pared to other practice settings given the open ward structure and minimal engineering controls available. additionally, it was critical to establish a shared model of safe practice given the diversity of staff knowledge and experience with general and covid-19 specific ipc practices. less expected, was the complexity of ppe inventory management. there was no computer access in the ppe distribution area, so inventory management was a labor-intensive, manual process prone to error. this risk was mitigated by assigning designated staff to the ppe distribution room. had the csf-l remained opened, tools such as the the national institute for occupational safety and health (niosh) ppe tracker mobile app could be used. however, future acs's should utilize computerized inventory management systems, staffed by skilled personnel, to track all inventory. one of the most important aspects of disaster and emergency response is ensuring effective, frequent and timely information exchange. information exchange and management should be based on a system of collaboration, partnership, and sharing. 11 while collaboration and partnership were a part of preparing the csf-l for patients, real-time information sharing to increase the ipc team's situational awareness of csf-l's capabilities and resource needs, was at times challenging, given the plethora of agencies, personnel, and teams working independently, yet simultaneously in an effort to prepare for occupancy. 12 all acs, particularly those developed in response to an emerging infectious threat such as sars-cov-2, will benefit from close partnerships between leaders, front-line and support staff, and ipc experts. finally, we believe our approach may have utility beyond the pandemic. use of the -4s's‖ framework, coupled with actionoriented learning using pdsa cycles, could be used in other surge situations. the ipc team worked quickly and efficiently to manage the constantly evolving circumstances and the time constraints that accompanied the opening of a covid-19 pandemic acs. despite the growing scarcity of ppe, the csf-l goals of ensuring an adequate supply of ppe and provid-ing the safest environment for both patients and staff were achieved. the ability to leverage our collective ipc knowledge, skills, abilities and energies to this situation has been extremely rewarding. in the spirit of volunteerism, we had the opportunity to work with an extraordinary group of people dedicated to a common goal. agency for healthcare research and quality: surge capacity-education and training for a qualified workforce city provides update on covid-19 for friday the pennsylvania department of health &the hospital and healthsystem association of pennsylvania (2020) exploring the concept of surge capacity. ojin:the online journal of issues in nursing factors associated with preparedness of the us healthcare system to respond to a pediatric surge during an infectious disease pandemic: is our nation prepared? hospital surge capacity: the importance of better hospital pre-planning to cope with patient surge during dengue epidemics -a systematic review considerations for alternate care sites infection control in healthcare personnel: infrastructure and routine practices for occupational infection prevention and control services hospital infectious disease emergency preparedness: a 2007 survey of infection control professionals pan american health organization. information management and communication in emergencies and disasters: manual for disaster response teams critical care surge response strategies for the 2020 covid-19 outbreak in the united states key: cord-319833-u9uuuu38 authors: rodriguez-martinez, carlos e.; sossa-briceño, monica p.; cortés-luna, jorge a. title: decontamination and reuse of n95 filtering facemask respirators: a systematic review of the literature date: 2020-07-08 journal: am j infect control doi: 10.1016/j.ajic.2020.07.004 sha: doc_id: 319833 cord_uid: u9uuuu38 introduction: as has happened in other emerging respiratory pandemics, demand for n95 filtering facemask respirators (ffrs) has far exceeded their manufacturing production and availability in the context of the sars-cov-2 pandemic. one of the proposed strategies for mitigating the massive demand for n95 ffrs is their reuse after a process of decontamination that allows the inactivation of any potentially infectious material on their surfaces. this article aims to summarize all of the available evidence on the different decontamination methods that might allow disposable n95 ffrs to be reused, with emphasis on decontamination from sars-cov-2. methods: we performed a systematic review of the literature in order to identify studies reporting outcomes of at least one decontamination method for inactivating or removing any potentially infectious material from the surface of n95 ffrs, specifically addressing issues related to reduction of the microbial threat (including sars-cov-2 when available), maintaining the function of n95 ffrs and a lack of residual toxicity. results: we identified a total of 14 studies reporting on the different decontamination methods that might allow disposable n95 ffrs to be reused, including small-scale energetic methods and disinfecting solutions/spray/wipes. among these decontamination methods, ultraviolet germicidal irradiation (uvgi) and vaporized hydrogen peroxide (vhp) seem to be the most promising decontamination methods for n95 ffrs, based on their biocidal efficacy, filtration performance, fitting characteristics, and residual chemical toxicity, as well as other practical aspects such as the equipment required for their implementation and the maximum number of decontamination cycles. conclusions: although all the methods for the decontamination and reuse of n95 ffrs have advantages and disadvantages, uvgi and vhp seem to be the most promising methods. an outbreak starting in december 2019 caused by the novel severe acute respiratory syndrome coronavirus 2 (sars-cov-2), declared a global pandemic by the world health organization (who) on march 11, 2020, has posed a severe threat to public health and local economies around the globe. 1 as the pandemic accelerates, the increased risk of infection of health-care workers due to a rise in their demand makes their safety, including an adequate provision of personal protective equipment (ppe), a cause of great concern. 2 recent guidelines proposed by the infectious diseases society of america (idsa) recommend the use of a reprocessed n95 respirator for reuse during respirator shortage based on laboratory evidence, due to lack of clinical experience with the decontamination process. 3 among the various ppes, disposable n95 filtering facemask respirators (ffrs) are of critical importance for confronting the sars-cov-2 pandemic because of their tight fit and their filtration capability of at least 95% of airborne particles, including large and small particles. 4 however, as has happened in other emerging respiratory pandemics, demand for n95 ffrs has far exceeded their manufacturing production and availability. this is, among other factors, due to the minimum number of n95 ffrs required for each health-care worker involved in direct patient contact, assuming adequate care is taken. for a recent respiratory pandemic outbreak of influenza, there were estimations of requirements of as many as 360 million ffrs, in scenarios assuming a pandemic duration of 24 weeks. 5 ideally, disposable n95 ffrs should be discarded after each patient encounter and after aerosol-generating procedures (considering that they are potentially fomites because they remove pathogenic microorganisms from aerosols generated by infected individuals), when they become damaged or deformed, when they no longer form an effective seal to the face, when they become wet or visibly dirty, when breathing becomes difficult, as well as when they become contaminated with blood, respiratory or nasal secretions, or other bodily fluids. 6 some of these recommendations are supported by evidence showing the probability of viral contamination and the viability of respiratory viruses on n95 ffrs and other inanimate surfaces for variable periods, the ability of the influenza virus to persist for 6 days on the outer side of the n95 ffrs having been demonstrated. 7, 8 specifically for sars-cov-2, although it is more stable on plastic and stainless steel than on copper and cardboard, viable virus can be detected for up to 72 hours. 9 one of the proposed strategies for mitigating the massive demand for n95 ffrs not met by manufacturing supply that typically occurs during a respiratory pandemic that helps to ensure their continued availability in healthcare environments is their reuse after a process of decontamination that allows the inactivation of any potentially infectious material on their surfaces. 10 although various decontamination methods have been used, there are concerns over certain characteristics of the n95 ffrs with respect to their utilization, such as alterations in their physical appearance/odor, structural integrity, filtration efficiency, fit and seal and filter airflow resistance, degradation of their material, and chemical residues that are potentially toxic or irritate the skin (due to the chemical disinfectants required for rinsing and drying). the requirement for specialized equipment for using the decontamination methods must also be considered, as well as their speed and ease of use, cost, and the maximum allowed number of decontamination cycles. 6 however, to the best of our knowledge, no systematic review has summarized the findings of studies that have assessed the above-mentioned advantages and disadvantages of all available decontamination methods for n95 ffrs. the present article aims to summarize all of the available evidence on the different decontamination methods that might allow disposable n95 ffrs to be reused, with emphasis on decontamination from sars-cov-2. potentially relevant studies were identified thorough a search of the literature in the electronic databases medline, embase, cinahl, and scopus up to july, 2020, using the terms ("decontamination"(mesh) or "equipment reuse"(mesh) or "microbial viability"(mesh) or "virus inactivation"(mesh) or "disinfection"(mesh) or "respiratory tract infections/prevention and control"(mesh)) and ("respiratory protective devices"(mesh) or "n95 respirator" or "filtering facepiece respirator"). two review authors (crm, mps) scanned the abstracts and titles of articles retrieved by the electronic databases according to the eligibility criteria, retrieving full copies of all those deemed potentially eligible for closer examination. disagreement was resolved by consensus. the electronic database searches were supplemented by information obtained from the references of the identified studies. we included citations in any language. to be included, the studies had to meet the following criteria: studies reporting outcomes of at least one decontamination method for inactivating or removing any potentially infectious material from the surface of n95 ffrs, including filtration performance, structural integrity, and potentially toxic or chemical residues postdecontamination. studies that reported on the efficacy of decontamination methods on elastomeric respirators were excluded. likewise, studies in which it was not possible to extract outcomes of interest separately for the different decontamination methods, or studies published solely in abstract form, were not eligible for inclusion in the review. two reviewers (cerm and jacl) independently used a data extraction sheet designed a priori to obtain the specific data required for this review. from the included studies, we extracted descriptive data (first author, year), type of decontamination method(s) used, and details of their implementation, such as the equipment required, speed and ease of use, cost, and the maximum allowed number of decontamination cycles. likewise, we extracted data on outcomes of relevance, including alterations in the physical appearance/odor, structural integrity, filtration efficiency, fit and seal, and filter airflow resistance of the n95 ffrs, as well as chemical residues that are potentially toxic or that irritate the skin upon use. figure 1 shows the selection process of the studies. the systematic search of databases retrieved 244 studies. among those, we excluded 237 studies. the most common reason for excluding studies was that they did not meet the eligibility criteria. eight additional studies that met the inclusion criteria were identified from the references of eligible articles. in the end, a total of 15 studies reporting on the different decontamination methods that might allow disposable n95 ffrs to be reused were included in the review and presented by type of decontamination method. upland, ca, usa), the lamp's uv-c wavelength irradiance ranged between 1.6 mw cm 2 and 2.2 mw cm 2 . virus-laden respirators were placed inside the cabinet directly under the ultraviolet lamp, with the convex panel facing the treatment, and were exposed for a total of 15 min at a uv-c wavelength dose of 18 kj m 2 . after the decontamination procedure, the reduction in viral recovery (expressed as log10 tcid50/ml reduction) was ≥4.54 and ≥4.65 for the ffrs models, respectively, and no viable virus was detectable, with the number of amplification cycles to detect vrna of 2.97 and 5.60 for the ffrs models, respectively. additionally, the post-decontamination filter performance analyses showed that the mean penetration of 1% nacl aerosol at 300 nm particle size was 0.99 and 0.37 for the ffr models, respectively. 12 viscusi et al. placed n95 ffrs on the working surface of a sterilgard iii laminar flow cabinet (the baker company, sanford, me, usa) fitted with a 40-wuv-c light (average uv intensity experimentally measured to range from 0.18 to 0.20 mw cm 2 ), fifteenminute exposure to each side (outer and inner), 176-181 mj cm-2 exposure to each side of the ffr, for a total time of 30 minutes. all laboratory experiments were conducted under standard laboratory conditions (21 ± 2 °c and relative humidity of 50%-10%) on triplicate sets of ffrs. ultraviolet germicidal irradiation treatment did not affect the filter aerosol penetration (pre-and post-decontamination average percentage of sodium chloride penetration of the three surgical n95 ffrs evaluated: 1.57 ± 0.83 vs. 1.86 ± 0.97, 0.335 ± 0.19 vs. 0.371 ± 0.21, and 0.716 ± 0.37 vs. 0.720 ± 0.37) or physical appearance of the ffrs. there were statistically significant, although not clinically significant, differences between pre-and post-decontamination measures of filter airflow resistance in two of the three surgical n95 ffrs evaluated (pre-and postaverage decontamination resistance in mmh 2 o: 8.4 ± 0.50 vs. 9.2 ± 0.44, 6.1 ± 0.15 vs. 7.1 ± 0.61, and 6.7 ± 0.17 vs. 6.6 ± 0.26). no known health risks to the user were identified. 13 in addition to these results, viscusi et al. also showed that n95 ffr users would be unlikely to experience a clinically meaningful reduction in fit, increase in odor, increase in discomfort, or increase in difficulty in donning after uvgi decontamination. 14 lindsley et al. exposed both sides of material coupons and respirator straps from four models of n95 ffrs to uvgi doses from 120 to 950 j/cm 2 and evaluated the particle penetration, flow resistance, bursting strengths of the individual respirator coupon layers, and breaking strength of the respirator straps. n95 ffrs were exposed to ultraviolet light with a primary wavelength of 254 nm (uv-c) in a custom-made 91 cm × 31 cm × 64 cm high chamber. the chamber was fitted with two 15-watt t-150 254 nm uv-c lamps in a reflective housing and lined with black felt to minimize reflections. uv-c irradiance was measured using a radiometer (ilt-1700, international light technologies, peabody, ma). uvgi exposure led to only a small increase in particle penetration (up to 1.25%) and had little effect on the flow resistance. uvgi exposure had a more pronounced effect on the strengths of the respirator materials. at the higher uvgi doses, the strength of the layers of respirator material was substantially reduced (in some cases, by >90%). the changes in the strengths of the respirator materials varied considerably among the different models of respirators. uvgi had less of an effect on the respirator straps; a dose of 2360j/cm 2 reduced the breaking strength of the straps by 20%-51%. 15 bergman et al. evaluated changes in physical appearance, odor, and laboratory performance (filter aerosol penetration and filter airflow resistance) of six n95 ffrs models after three cycles of decontamination with uvgi. the determined by a 50% tissue culture infectious dose (tcid50/ml) assay. significant reductions (≥3 log) in influenza viability for both soiling conditions were observed on facepieces from 12 of 15 ffr models (with a mean log reduction ranging from 1.42 to 4.84 log tcid50/ml for mucin-soiled facepieces, and from 1.25 to 4.64 log tcid50/ml for sebum-soiled facepieces) and straps from 7 of the 15 ffr models (with a mean log reduction ranging from 0.00 to 4.31 log tcid50/ml for mucin-soiled straps, and from 0.08 to 4.40 log tcid50/ml for sebum-soiled straps). 17 heimbuch et al. evaluated the decontaminant efficacy and the durability and functionality of fifteen n95 ffr models after multiple cycles of uvgi. using a mineralight® xx-20s 20-w uv bench lamp, four uv doses were evaluated: 1 × 103, 5 × 105, 1 × 106, and 2 × 106 µj/cm2. for each test, ffrs were inoculated in a class ii biological safety cabinet (bsc) with ten 1-µl droplets of ~109 tcid50/ml h1n1 influenza onto each of the four surfaces selected for inoculation. after the droplets had dried, a soiling agent (synthetic skin oil or artificial saliva buffer) was applied over each inoculated surface to act as a protective factor. the test results were reported as the reduction of the virus titer due to treatment with uv, expressed as log10. the tcid50/ml was determined using the spearman-karber method. uvgi performance varied considerably for all 15 ffr models tested, with log reductions ranging from 0.00 to 4.85 log10 tcid50/ml, based on inoculation location, soiling agent, and control recovery. for all three soiling conditions, a direct relationship was demonstrated between uv dosage and influenza decontamination, with no viable virus detected after uv treatment ≥1 j/cm 2 . additionally, it was demonstrated that up to 20 cycles of uvgi treatment (approximately 1 j/cm2 per cycle) do not exert a meaningfully significant effect on fit, airflow resistance, or particle penetration for the 15 ffr models tested. strap tension data indicated that 10 uvgi cycles do not have a significant effect on ffr straps, but 20 uvgi cycles may have a significant effect on straps from some n95 ffr models (3m 1860, 3m 1870, and kimberly-clark pfr models). 10 lin et al. determined the relative survival of bacillus subtilis spores loaded onto n95 ffrs after uvgi (uva 365 nm, uvc 254 nm) decontamination under a worst-case temperature (37 °c, similar to body temperature) and humidity (95% relative humidity, the maximum feasible relative humidity value) that prevails when an ffr is placed in a zipper bag in a healthcare worker's pocket. the treatment proceeded as follows: an n95 ffr was placed 10 cm below a 6 w handheld uv lamp (model uvgl-58, vup llc, upland, ca) that emitted a wavelength of 254 nm (uvc, 18.9 mw/cm 2 ) or 365 nm (uva, 31. 2 mw/cm 2 ). both sides of each n95 ffr were exposed for different lengths of time: 1, 2, 5, 10, and 20 minutes, in a bsc. the uv intensity was measured using a handheld laser power and energy meter (ophir nova ii, model nova ii pd300-uv) and was reported as a mean of five measurements over a 10 × 10 mm aperture with a swivel mount and a removable filter. colony-forming units (cfus) were counted, and their relative survival (rs) was calculated. without decontamination, 59 ±8% of the loaded spores survived for 24 hours. no colony was recovered after exposure to uv-c for as little as 5 minutes. however, rs remained above 20% after 20 minutes of irradiation by uv-a, exponentially decaying with increased exposure time. 18 fischer et al. analyzed the ability of uv radiation to inactivate sars-cov-2 on n95 ffrs (50 µl of 10 5 tcid50/ml of sars-cov was applied on n95 and stainless steel) and used quantitative fit testings to measure their filtration performance after each decontamination run and 2 hours of wear, for three consecutive decontamination and wear sessions. plates with fabric and steel discs were placed under an led high-power uv germicidal lamp (effective uv wavelength 260-285 nm) without the titanium mesh plate (ledi2, houston, tx) 50 cm from the uv source. at 50 cm, the uvab power was measured at 5 µw/cm2 using a general uvab digital light meter (general tools and instruments new york, ny). the plates were removed at 10, 30, and 60 minutes, and 1 ml of cell culture medium added. n95 ffrs integrity was quantitatively determined using the fit factor, a measure of filtration performance: the ratio of the concentration of particles outside the mask to the concentration inside, requiring a minimum fit factor of 100 for a mask to pass a fit test. uv inactivated sars-cov-2 rapidly from steel (decay rates of viable virus titers over time and half-lives; median, interquartile range: 0.733, 0.649-0.802 min), but more slowly on n95 fabric (decay rates of viable virus titers over time and half-lives; median, interquartile range: 6.26, 5.31-7.15 min). the uv-treated masks retained filtration performance comparable to the control group after two cycles of decontamination and maintained acceptable performance after three cycles. 19 liao et al. process but differing in some aspects (e.g. gas concentration, chamber volume, and duration). respirators tested using these treatments were shipped to and from a commercial facility specializing in low-temperature sterilization methods. four ffr samples were placed in standard poly/paper pouches and treated with eto. all respirator samples were exposed to eto for one hour, followed by a four-hour aeration interval. the respirators were shipped back to the investigators and subsequently tested in house for filtration efficiency within 72 hours of receipt. after eto decontamination, the average penetration slightly increased for n95 ffrs, though not beyond their respective certification criteria (mean and standard deviation % penetration: 0.7 ± 0.267 vs. 0.729 ± 0.136 vs. 0.35 ± 0.019, for as-received, eto 3m 5xl, and eto 3m 4xl postdecontamination, respectively). eto 3m 5xl was found to be slightly less degraded than eto 3m 4xl. 11 viscusi et al. differing only in duration and capacity. respirators tested using these treatments were shipped to and from a commercial facility specializing in low-temperature sterilization methods and were tested in-house for filtration efficiency within 72 hours of receipt from the commercial facility. the sterrad® sterilization process is less effective when used on cellulose-based products; hence the use of tyvek/mylar pouches was required. since there were no inherent hazardous residues as a result of the sterrad® process, no aeration interval was necessary. aluminum nosebands were slightly tarnished and visibly not as shiny when compared with their as-received counterparts after both sterrad® treatments. for both treatments, the average penetration of the 95 ffr model did not significantly increase and remained below certification limits. sterrad® nx was found to be slightly less degraded than sterrad® 100s, but the difference was not statistically significant (mean and standard deviation % penetration: ffrs after bleach decontamination. the treatment proceeded as follows: a 0.4 ml volume of bleach with various concentrations (5.4% (w/w) as cl2: original; 2.7%: one part bleach to one part of deionized water; 0.54%: one part bleach to nine parts of deionized water) was added to the center of the surface of the n95 ffr using a pipette, the ffr was then dried in a petri dish in a bsc for 10 minutes, the cfus were counted, and their (rs) was calculated. without decontamination, 59 ±8% of the loaded spores survived for 24 hours. in the bleach decontamination test, no colony was recovered after 5.4%, 2.7% or 0.54% sodium hypochlorite was used, constituting no dilution, twofold, and 10-fold dilution, respectively. 18 bergman et al. evaluated changes in the physical appearance, odor, and laboratory performance of six n95 ffr models after three cycles of decontamination with bleach. the experimental conditions and parameters were as follows: 30-min submersion in 0.6% (one part bleach to nine parts of deionized water) solution of sodium hypochlorite (original concentration = 6% available as cl2). manufacturing specification: 6.00 ±0.06% bleach decontamination caused various effects: for all ffr models, metallic nosebands were slightly tarnished and visibly not as shiny when compared with their as-received counterparts. for those models with staples, the staples were oxidized to varying degrees. some models had dissolution of nose pads, and discoloration (yellowing) of inner nose pads, material adjacent to nose pad, and other areas of the ffrs (bleeding of printed ink lettering). additionally, following air-drying between exposure cycles (at least 16 hrs), all ffrs that were exposed to bleach were dry to the touch, and all still had a characteristic bleach odor. 16 liao et al. sprayed three models of n95 ffrs with approximately 0.3−0.5 ml of household chlorine-based disinfectant (∼2% naclo). samples were left to air-dry and off-gas completely, while hanging. from the first disinfection, ethanol drastically degraded the filtration efficiency (73.11% ± 7.32), while the pressure drop remained comparable (9.0pa ± 1.0). 20 in an oven (thermo fisher scientific inc., marietta, oh, usa), and heated to 65 ± 5 °c for 3 h. this allowed the liquid to reach the desired temperature before any decontamination tests. for testing, the container was removed from the oven, and a single virus-contaminated respirator was placed on the rack. for each decontamination procedure, the container was opened and the ffr placed onto the rack with the convex surface pointed toward the water layer. the container was then sealed and returned to the oven for the 20-min treatment. after the decontamination procedure, the reduction in viral recovery (expressed as log10 tcid50/ml reduction) was ≥4.62 and ≥4.65 for the ffr models, respectively, and no viable virus was detectable, with several amplification cycles to detect vrna of 5.62 and 42.45 for the ffr models, respectively. additionally, the post-decontamination filter performance analyses showed that the mean penetration of 1% nacl aerosol at 300-nm particle size was 1.04 and 0.99 for the ffr models, respectively. 12 fischer et al. analyzed the ability of heat to inactivate sars-cov-2 on n95 ffrs (50 µl of 105 tcid50/ml of sars-cov was applied on n95 and stainless steel) and used quantitative fit testings to measure their filtration performance after each decontamination run and 2 hours of wear, for three consecutive decontamination and wear sessions. plates with fabric and steel discs were placed in a 70 °c oven. plates were removed at 10, 20, 30, and 60 minutes, and 1 ml of cell culture medium added. the n95 ffrs' integrity was quantitatively determined using the fit factor, a measure of filtration performance: the ratio of the concentration of particles outside the mask to the concentration inside, requiring a minimum fit factor of 100 for a mask to pass a fit test. cfus were counted, and their rs was calculated. without decontamination, 59 ±8% of the loaded spores survived for 24 hours. just after spiking with ethanol, the rs was found to have declined from 100% to 68%-75%. when 0.4 ml of 70% ethanol was applied, the rs fell to 22% in 24 hours. the rs fell to 20% when 80% ethanol was used. 18 fischer et al. analyzed the ability of 70% ethanol to inactivate sars-cov-2 on n95 ffrs (50 µl of 105 tcid50/ml of sars cov-2 was applied on n95 and stainless steel) and used quantitative fit testings to measure their filtration performance after each decontamination run and 2 hours of wear, for three consecutive decontamination and wear sessions. fabric and steel discs were placed into the wells of one 24-well plate per time-point and sprayed with 70% ethanol to saturation. the plate was tipped to near vertical, and five passes of ethanol were sprayed onto the discs from approximately 10 cm. after 10 minutes, 1 ml of cell culture medium was added. the n95 ffrs' integrity was quantitatively determined using the fit factor, a measure of filtration performance: the ratio of the concentration of particles outside the mask to the concentration inside, requiring a minimal fit factor of 100 for a mask to pass a fit test. ethanol yielded extremely rapid inactivation both on n95 (decay rates of viable virus titers over time and half-lives; median, interquartile range: 0.639, 0.55-0.721 min) and on stainless steel (decay rates of viable virus titers over time and half-lives; median, interquartile range: 1.06, 0.888-1.23 min). quantitative fit tests showed that the filtration performance of the n95 ffrs was not markedly reduced after a single decontamination with 70% ethanol. however, subsequent rounds of decontamination caused sharp drops in the filtration performance of the ethanol-treated masks. 19 liao et al. immersed three models of n95 ffrs into a solution of 75% ethanol and left them to air-dry (hanging), and they were subsequently tested. at the first disinfection, ethanol drastically degraded the filtration efficiency (56.33% ± 3.03), while the pressure drop remained comparable (7.7pa ± 0.6). 20 heimbuch et al. evaluated the ability of commercially available wipe products to clean three models of surgical n95 ffrs contaminated with aerosols of mucin or viable staphylococcus aureus. after cleaning, ffrs were separated into components (nose pad, fabrics, and perforated strip), and contaminants were extracted and quantified. filtration performance was assessed for cleaned ffrs. wipe products selected for this study were 504/07065 respirator cleaning wipes (3m company, stpaul, mn),15, which contain benzalkonium chloride (bac); hype-wipes (current technologies, inc, crawfordsville, in),16, which contain 0.9% hypochlorite (ocl); and pampers wipes (proctor &gamble, cincinnati, oh),17, which contain no active antimicrobial ingredients (i.e., inert). s. aureus was applied to both interior and exterior ffr surfaces (in separate experiments) to provide sufficient sensitivity for reliable analysis. mucin was applied as a heavy loading (1 mg/cm2) only to exterior surfaces. after cleaning, the ffrs were incubated for 15 minutes at room temperature before quantification of contaminants. the filters' performance was evaluated after three cleaning cycles using a model 8130 automated filter tester (tsi inc, shore-view, mn). while no mucin was detected in replicates using the ocl wipes, the mean removal efficiency of mucin by bac and inert wipes ranged from 21.47% to 76.41%. otherwise, the mean removal efficiency of staphylococcus aureus by ocl wipes ranged from 98.98 to >99.99%, the mean removal efficiency of s. aureus by bac wipes ranged from 68.92 to >99.99%, and the mean removal efficiency of s. aureus by inert wipes ranged from 59.37 to >96.53%. removal was less effective from nose pads and perforated edges. although particle penetration following cleaning yielded mean values <5%, bac wipes caused more penetration than the other wipes, this difference being significant for two models of ffrs. 24 viscusi et al. evaluated the filtration performance of an n95 ffr after tap water, using a poly-dispersed sodium chloride aerosol test method. this treatment involved submerging the test respirators in tap water for 30 minutes and was included as a control to reveal any effect due to immersion in tap water and air drying. no significant visible changes were detected. as expected, the average filter penetration was unchanged for n95 ffrs (mean and standard deviation % penetration: 0.7 ±0.267 and 0.72 ± 0.202, for as-received and tap water post-decontamination, respectively). 11 viscusi et al. evaluated the filtration performance of an n95 ffr after soap and water at two different time intervals, using a poly-dispersed sodium chloride aerosol test method. this systematic review summarized all the existing evidence on the different decontamination methods that might allow disposable n95 ffrs to be reused, specifically addressing issues related to biocidal efficacy, filtration performance, fitting characteristics, and residual chemical toxicity, as well as other practical aspects such as the equipment required for their implementation and the maximum number of decontamination cycles. our findings show that the issues mentioned above largely depend not only on the decontamination method itself, but also on other factors, such as the n95 ffr model, the presence of soiling agents, the surface type, the directness of exposure to the target surface for decontamination, the type of nucleic acid of the virus, the water-vapor content on the surface, and specific characteristics of each decontamination method, such as dose, intensity, concentration, and time of exposure. our review shows that although not all methods have been evaluated for their efficacy in virus inactivation, uvgi, vhp, heat, and ethanol are specifically efficacious against sars-cov-2. our review supports the recent recommendations made by the idsa related to the use of reprocessed n95 for reuse during a contingency 3 and provides wider support for alternative methods. it must also be recognized that clinical evidence for the reuse of decontaminated n95 is lacking, and such a study would be of interest in crisis-capacity settings but also relevant for less-developed countries. although all the methods have advantages and disadvantages (table 1) , uvgi and vhp seem to be the most promising decontamination methods for n95 ffrs. uvgi decontamination has many benefits: it is the most frequently studied and reported decontamination method for n95 ffrs that has demonstrated significant reductions in influenza virus recovery and viability even with soiling conditions (mucin and sebumsoiled facepieces), 17 all these biocidal effects have been demonstrated without known health risks to the users nor a meaningfully significant effect on filter aerosol penetration, filter airflow resistance, [11] [12] [13] 15 fit and seal, odor (although a singed smell has been reported on ffrs following uvgi treatment, this does not necessarily indicate toxicity, and it generally dissipates naturally within 4 hours), 25 discomfort, difficulty in donning, or physical appearance 14 after up to 20 of cycles of decontamination. 10 additionally, uvgi is the most viable treatment for large-scale applications, due to its simplicity of use and its ability to rapidly scale up the process by adding inexpensive ffr uvgi exposure units. uvgi technology has also been developed for whole-room decontamination for hospitals, which provides opportunities for dual-use technologies and reduction of implementation costs. 13 however, several aspects need to be taken into account before being truly optimistic: uvgi decontamination is based on supplying an adequate dose to the contaminated area. 26 the uvgi dose required for decontamination, which is microbe specific (e.g., a direct relationship between uv dosage and influenza decontamination has been demonstrated, with no viable virus detected after uv treatment ≥1 j/cm 2 10 ), is a function of irradiance and time. 26 however, at the higher uvgi doses, there are greater reductions in the strength of the layers of ffr material. 15 furthermore, uvgi efficiency is hampered by shadowing produced by the multiple layers of the n95 ffrs. 17 an additional factor to consider is that uvgi performance can vary among different models of n95 ffrs, different parts of the respirators, distinct types of uvgi, and number of cycles of decontamination. although 10 uvgi cycles do not have a significant effect on ffr straps, 20 cycles may have a considerable impact on the strap tension of some n95 ffr models (3m 1860, 3m 1870, and kimberly-clark pfr models). 10 while no colony of b. subtilis was recovered after 5 minutes of exposure to uv-c, rs remained above 20% after 20 minutes of irradiation by uv-a. 18 moreover, uvgi has been demonstrated to inactivate sars-cov-2 rapidly on steel but more slowly on n95 fabric, likely due to its porous nature. 19 finally, uvgi decontamination is limited by the available working surface area of a biosafety cabinet equipped with a uv-c source or other area being irradiated by a uvgi source. 13 vhp is another widely-studied decontamination method for n95 ffrs that has been shown to have several advantages: complete inactivation of g. stearothermophilus spores following 50 repeat aerosol inoculation/decontamination cycles, 21 complete eradication after a single vhp cycle of 3 aerosolized bacteriophages (t1, t7, and pseudomonas phage phi-6), which are a reasonable proxy for sars-cov-2, 22 and extremely rapid inactivation of sars-cov-2 both on n95 and on stainless steel. 19 all these biocidal effects have been demonstrated without meaningfully significant effects on filtration performance, filter aerosol penetration, fit, and filter airflow resistance after up to 50 cycles of decontamination. 21 additionally, there are no vapors potentially toxic to humans nor environmentally hazardous residues as a result of the vhp decontamination process. 11 however, after vhp decontamination, some studies have reported a fragmentation of the elastic material in the straps when stretched (after 30 hpv, but not after 10 or 20 hpv cycles) 21 and a slight tarnishing of the metallic nosebands. 13 a potential disadvantage is that although the total vhp cycle time is short compared to other decontamination methods, the throughput capability of vhp processing is limited by the fact that cellulose-based products (e.g., cotton, which may be present in some head straps or some ffr layers) absorb hydrogen peroxide and can cause the sterrad® cycle to abort due to low hydrogen peroxide vapor concentration. 13 as in the case of uv treatment, some information has cast doubt on the number of cycles allowed while maintaining the integrity of the fit testing after more than two wear sessions. 19 the results of our review support and build on previous recommendations for the most viable decontamination methods for n95 ffrs. concerning decontamination and reuse of ffrs, the centers for disease control and prevention (cdc) recognizes uvgi, vhp, and moist heat as the most promising potential methods for decontaminating ffrs. additionally, the cdc also accept steam treatment and liquid hydroxygen peroxide as promising methods, but with some limitations, and eto as a promising method but with serious limitations. 6 the asia pacific center for evidence-based healthcare concluded, based on laboratory-based studies, that uvgi, mgs, warm moist heath, and vhp were shown to be effective in reducing either viral or bacterial load while still maintaining the integrity of n95 ffrs. 27 hamzavi et al. consider that given that many of our health care providers are using substitutes for n95 ffrs that offer very limited degree of protection, using uvgi and repurposing phototherapy devices could be the best practical solution at this time. 28 also, supporting the findings of our review, vhp and uvgi for decontaminating and reusing n95 respirators are being used at the duke university health systemy 29 and at the university of nebraska medical center, 30 respectively. as an additional contribution, our review provides information about the n95 ffr models tested with each decontamination method, as well as the specific models that had some problem with each decontamination method (table 1 ). in conclusion, although all the methods for decontaminating and reusing n95 ffrs have advantages and disadvantages, uvgi and vhp seem to be the most promising methods, based on their reduction of the microbial threat (including sars-cov-2) while maintaining the function of n95 ffrs as well as the lack of residual toxicity. future studies are required in order to establish the efficacy and security of these decontamination methods on different n95 ffr models and the maximum allowed number of cycles of decontamination under different conditions. 17 substantial reduction in the recovery of pathogens such as bacillus subtilis spores after exposure to uvgi for as little as 5 minutes 18 inactivation of influenza a (h1n1), avian influenza a (h5n1), influenza a (h7n9) a/anhui/1/2013, influenza a (h7n9) a/shangai/1/2013, mers-cov, sars-cov, and sars-cov-2 10, 19 no significant effect on filter aerosol penetration, filter airflow resistance, fit and seal, odor, discomfort, difficulty in donning, or physical appearance after up to 20 of cycles of decontamination [10] [11] [12] [13] [14] [15] 25 no significant effect on filtration efficiency after 10 cycles of decontamination. 20 reduction in the strength of the layers of ffr material (at higher uvgi doses)/ (3m 1860, 3m 9210, gerson 1730, kimberly-clark 46727) 15 uvgi efficiency hampered by shadowing produced by the multiple layers of the n95 ffrs/ (all ffr models) 17 uvgi performance can vary among different models of n95 ffrs, different parts of the respirators, distinct types of uvgi, and number of cycles of decontamination considerable impact on the strap tension of some n95 ffr models (with 20 cycles of decontamination)/ (3m 1860, 3m 1870, kimberly-clark pfr) 10 better reduction in b. subtilis recovery with uv-c than with uv-a/ (3m 8210) 18 uv-treated ffrs were able to withstand 10 cycles of treatment, but efficiency eventually decayed to 93% at 20 cycles, making it unsuitable for n95-grade ffrs by itself/ (3m 8210, 4c air, inc. (gb2626 kn95), esound (gb2626 kn95), onnuriplan (kfda kf94)). 20 3m 1860 3m 1870 3m 9211 n95-a n95-b n95-c sn95-d sn95-e sn95-f complete inactivation of g. stearothermophilus spores following 50 repeated aerosol inoculation/decontamination cycles 21 complete eradication after a single vhp cycle of 3 aerosolized bacteriophages (t1, t7, and pseudomonas phage phi-6) 22 extremely rapid inactivation of sars-cov-2 both on n95 and on stainless steel. 19 no significant effects on filtration performance, filter aerosol penetration, fit, and filter airflow resistance after up to 50 cycles of decontamination 21 no vapors potentially toxic to humans nor environmentally hazardous residues as a result of the vhp decontamination process 11 fragmentation of the elastic material in the straps when stretched (after 30hpv, but not after 10 or 20 vhp cycles)/ (3m 1860) 21 slight tarnishing of the metallic nosebands/ (all ffr models) 13 ethylene oxide (eto) n95 23 no significant affection of filter aerosol penetration or filter airflow resistance of ffrs (after 2 minutes of microwave exposure) [11] [12] [13] 16 no significant reduction in fit, increase in odor, increase in discomfort, or increased difficulty in donning 14 no known health risks to the users 13 models) 11 partial separation of the inner foam nose cushion and slight melting of the head straps from some ffr samples/ (sn95-e and sn95-d, respectively) 16 microwave oven irradiation melted samples from one ffr model/ (sn95-e) 13 filtration material melted in areas adjacent to the metallic nosebands/ (sn95-e) 13 99-100% biocidal efficacy, indicating effective sterilization of bacillus subtilis spores 18 no significant affection of filter aerosol penetration or filter airflow resistance tarnishing of the aluminum nosebands/ (all ffr models) 11, 13, 16 stiffening of the filter media and elastic straps (treatment with 5.25% bleach) 11 discoloration of the inner nose cushion of one of the three n95 ffrs evaluated/ (sn95-e) 13 characteristic smell of bleach/ (all ffr models) 13 oxidation of staples/ (n95-b, n95-c, sn95-e, sn95-f) 16 dissolution of nose pads/ (sn95-e) 16 discoloration (yellowing) of inner nose pads/ (n95-a, sn95-e, sn95-f) 16 discoloration of other areas of the ffr (bleeding of printed ink lettering)/ (sn95-f) 16 yellowing of the material adjacent to nose pad/ (sn95-e) 16 from the first disinfection, bleach drastically degraded the filtration efficiency/ (3m 8210, 4c air, inc. (gb2626 kn95), esound (gb2626 kn95), onnuriplan (kfda kf94)). 20 satisfactory decontamination of influenza virus on n95 ffrs as measured by a virus culture method 12 no significant affection of filter aerosol penetration of ffrs 12, 16, 19 no significant affection of filter airflow resistance of ffrs 16 no observable physical change in ffrs 16 no clinically significant reduction in fit, increase in odor, increase in discomfort, or increase in difficulty in donning 14 no significant affection of filtration efficiency or pressure after 10 cycles of decontamination. 20 increase in filtration penetration (at a temperature of 80 °c) 11 more than one cycle of decontamination caused sharp drops in the filtration performance of n95 ffrs/ (3m 9211) 19 n95 ffrs were largely melted and unusable after only 22 minutes of treatment at 160 °c 11 partial separation of the inner foam nose cushion and slight melting of the head straps from some ffr samples/ (sn95-e and sn95-d, respectively) 16 extremely rapid inactivation of sars-cov-2 both on n95 and on stainless steel 19 filtration performance of n95 ffrs was not markedly reduced after a single decontamination with 70% ethanol 19 higher survival of bacillus subtilis spores than with other decontamination methods/ (3m 8210) 18 more than one cycle of decontamination caused sharp drops in the filtration performance of the ethanol-treated masks/ (3m 9211) 19 from the first disinfection, ethanol drastically degraded the filtration efficiency/ (3m 8210, 4c air, inc. (gb2626 kn95), esound (gb2626 kn95), onnuriplan (kfda kf94)). 20 n95-a n95-b n95-c sn95-d sn95-e sn95-f no significant affection of filter aerosol penetration of ffrs 11, 16 no significant affection of filter airflow resistance of ffrs 16 slight fading of the label ink on the fabric of ffrs (treatment with 6% lhp for 30 minutes) 11 oxidation of the staples to varying degrees (for those models that use staples)/ (n95-b, n95-c, sn95-e, sn95-f) 16 effective sterilization of almost 100% of bacillus subtilis spores 18 n95 ffrs were deformed, shrunken, stiff, and mottled (for both 15 and 30 minutes of treatment) 11 marked increase of filter aerosol penetration of ffrs (for both 15 and 30 minutes of treatment) 11 a novel coronavirus outbreak of global health concern covid-19: protecting health-care workers infectious diseases society of america guidelines on infection prevention for health care personnel caring for patients with suspected or known covid-19 hospital respiratory protection program toolkit. resources for respirator program administrators pandemic influenza preparedness and response guidancefor healthcareworkers and healthcare employers occupational safety and healthadministration decontamination and reuse of filtering facepiece respirators persistence of the 2009 pandemic influenza a (h1n1) virus on n95 respirators transfer of bacteriophage ms2 and fluorescein from n95 filtering facepiece respirators to hands: measuring fomite potential aerosol and surface stability of sars-cov-2 as compared with sars-cov-1 mitigate a shortage of respiratory protection devices during public health emergencies effect of decontamination on the filtration efficiency of two filtering facepiece respirator models effectiveness of three decontamination treatments against influenza virus applied to filtering facepiece respirators evaluation of five decontamination methods for filtering facepiece respirators impact of three biological decontamination methods on filtering facepiece respirator fit, odor, comfort, and donning ease effects of ultraviolet germicidal irradiation (uvgi) on n95 respirator filtration performance and structural integrity evaluation of multiple (3-cycle) decontamination processing for filtering facepiece respirators ultraviolet germicidal irradiation of influenza-contaminated n95 filtering facepiece respirators relative survival of bacillus subtilis spores loaded on filtering facepiece respirators after five decontamination methods assessment of n95 respirator decontamination and re-use for sars-cov-2 can n95 respirators be reused after disinfection? how many times? final report for the bioquell hydrogen peroxide vapor (hpv) decontamination for reuse of n95 respirators hydrogen peroxide vapor sterilization of n95 respirators for reuse evaluation of microwave steam bags for the decontamination of filtering facepiece respirators cleaning of filtering facepiece respirators contaminated with mucin and staphylococcus aureus amendment 1 -limited study evaluating uvgi-treated ffr odor a method to determine the available uv-c dose for the decontamination of filtering facepiece respirators what are the effective methods of decontaminating n95 mask for reuse? asia pacific center for evidence based healthcare abdriged-igc-am-02apr-2020.pdf (accesed at ultraviolet germicidal irradiation: possible method for respirator disinfection to facilitate reuse during the covid-19 pandemic decontamination and reuse of n95 respirators with hydrogen peroxide vapor to address worldwide personal protective equipment shortages during the sars-cov-2 (covid-19) pandemic the authors thank mr. charlie barret for his editorial assistance. isopropyl alcohol n95 key: cord-292981-7qbi7wqr authors: memarzadeh, farhad; olmsted, russell n.; bartley, judene m. title: applications of ultraviolet germicidal irradiation disinfection in health care facilities: effective adjunct, but not stand-alone technology date: 2010-06-07 journal: am j infect control doi: 10.1016/j.ajic.2010.04.208 sha: doc_id: 292981 cord_uid: 7qbi7wqr this review evaluates the applicability and relative contribution of ultraviolet germicidal irradiation (uvgi) to disinfection of air in health care facilities. a section addressing the use of uvgi for environmental surfaces is also included. the germicidal susceptibility of biologic agents is addressed, but with emphasis on application in health care facilities. the balance of scientific evidence indicates that uvgi should be considered as a disinfection application in a health care setting only in conjunction with other well-established elements, such as appropriate heating, ventilating, and air-conditioning (hvac) systems; dynamic removal of contaminants from the air; and preventive maintenance in combination with through cleaning of the care environment. we conclude that although uvgi is microbiocidal, it is not “ready for prime time” as a primary intervention to kill or inactivate infectious microorganisms; rather, it should be considered an adjunct. other factors, such as careful design of the built environment, installation and effective operation of the hvac system, and a high level of attention to traditional cleaning and disinfection, must be assessed before a health care facility can decide to rely solely on uvgi to meet indoor air quality requirements for health care facilities. more targeted and multiparameter studies are needed to evaluate the efficacy, safety, and incremental benefit of uvgi for mitigating reservoirs of microorganisms and ultimately preventing cross-transmission of pathogens that lead to health care-associated infections. ultraviolet germicidal irradiation (uvgi) has been used to ''scrub'' the air in health care facilities and laboratories for many decades. uvgi is known to be efficacious to varying degrees in controlling the circulation of airborne infectious particles. approximately 60% of all uvgi air disinfection systems are installed in health care facilities. according to kowalski and bahnfleth, 1 this equates to 41% in hospitals and 19% in clinics. until recently, most of the experimental data that led to the development of uvgi systems were decades old. aside from anecdotal observations, little information about the actual performance of these systems in hospital rooms was available. although uv light is known to inactivate microorganisms, limiting their ability to grow and multiply when inhaled or picked up on surfaces, there is insufficient evidence on which to base a decision to rely solely on uvgi as an engineering control for preventing health care-associated tuberculosis (tb) transmission. 2 numerous laboratory studies, dating back to the 1930s, have been conducted to analyze the efficacy of uvgi for various microorganisms in a range of temperature and humidity conditions; few studies have evaluated the practical application of uvgi in health care buildings, however. 3 most of the existing evidence comes from laboratory investigations conducted under simulated conditions. our search revealed only one study that has been conducted in a physically realistic setting under controlled conditions. 4 that study served as the basis for the 2009 national institute for occupational safety and health (niosh) technical guidance document on the use of uvgi systems to protect health care providers from occupational tb infection. 5 this review examines the gaps in existing evidence and highlights design and operational factors that can significantly impact the efficacy of uvgi systems. myocobacterium tuberculosis, an obligate inhalational airborne pathogen, is inactivated by uvgi systems, which are most often are installed in the upper portion of rooms to disinfect air. today uvgi is receiving renewed interest, given the emergence of new infectious diseases such as pandemic strains of influenza, the ongoing threat of bioterrorism, and increased controls for aerosol-generating procedures. 6 in addition, highly drug-resistant strains of m tuberculosis have been reported in several countries. 7 others have also highlighted problems from pathogens known to survive in the environment, such as multidrugresistant acinobacter baumannii, clostridium difficile, and others, which are increasingly the cause of invasive infections and outbreaks in a various settings. [8] [9] [10] [11] [12] four technological methods can be used to reduce the risk of airborne transmission: pressurization, dilution, filtration, and purification. pressure. differential pressurization refers to measurable differences in air pressure that creates a directional airflow between adjacent spaces. for example, airflow into airborne infection isolation rooms (aiirs) ensures that the rooms are negative with respect to adjacent spaces, such as corridors. positive pressure, or airflow out of a defined space, is also common in facilities, used to mitigate the entrance of contaminants from adjacent areas into spaces in which invasive procedures are performed, such as an operating and procedure rooms. dilution. high ventilation rates, in terms of high values of air changes/hour (ach), control particles by removal through ventilation. current guidelines suggest a value of 12 ach for new facilities when designing an aiir, with 6 ach the absolute minimum value. the trade-off with this means of control is that increasing the ventilation rate results in diminishing returns in terms of removal; that is, there is increased removal of particulates with ach .12, but at a cost of greater energy consumption. thus, the incremental benefit to prevent cross-transmission is much more difficult to demonstrate beyond 12 ach. for other spaces, such as operating rooms, national guidelines recommend 20 ach. filtration. filters are a key element of air-handling units (ahus) that supply air to occupied spaces. there are two banks of filters: a prefilter of approximately 30% particle removal efficiency (defined in terms of a minimum efficiency reporting value [merv] as merv 7), followed by a final filter of 90%-95% efficiency (merv 14) . high-efficiency particulate air (hepa) filtration can be used to supplement other recommended ventilation measures by providing a minimum removal efficiency of 99.97% of 0.3-mm particles. hepa filters are typically used in ventilation systems that recirculate the air from an aiir or from a portable device. hepa filters also are used to filter special care areas for highly immunocompromised patients, such as a protective environment room as part of a bone marrow transplantation unit. proper installation, maintenance, and monitoring of the hepa filters is essential. purification. purifying the air through uvgi destroys the infectious agents in the air through exposure to ultraviolet (uv) radiation, which damages the nucleic acid of bacteria and viruses, including m tuberculosis, preventing replication. 13 for spores, uv-c exposure is postulated to result in the formation of lethal photoactive products. airborne transmission of infectious agents involves droplets that are expelled by sneezing or coughing or are otherwise distributed into the air. although the liquid/vapor around the infectious agent evaporates, the residue (or droplet nuclei) may remain in the air for long periods, depending on such factors as particle size, velocity, force of expulsion, particle density, infectivity (ie, viability of the microorganism when exposed to the environment and its ability to cause infection when a susceptible host is subsequently exposed), humidity, and rate of air flow. roy and milton 14 suggested that transmission of infectious agents does not correlate solely with the size of the microbes in droplet nuclei or larger droplets. the size can range from obligate inhalational airborne pathogens, such as m tuberculosis, to preferential inhalational transmission, such as measles virus or varicella-zoster (vzv) (based on the ability to cause infection in distal airways), to opportunistic pathogens like sars-cov that take advantage of unique environmental and clinical circumstances that permit dissemination over several meters. for m tuberculosis, the prototype obligate inhalational pathogen, airborne droplet nuclei containing this agent can travel via air currents, aided by the ventilation system, and be spread over a wide area. the disease-causing organisms then are inhaled and cause infection. induction of cough by chest physiotherapy. there is theoretical chance that pathogen-laden droplets expelled during these procedures might travel further distances and reach deeper into the respiratory tract of susceptible persons. concerns over the protection of health care personnel performing these types of procedures on patients with h1n1 2009 infection led to recommendations for higher facepiece filtering devices, such as n95 respirators. the latter have traditionally been required only to protect health care personnel against occupational exposure to m tuberculosis. droplet transmission involves relatively short-range movement of the infectious agent, over a distance of 1-2 m. some of these agents (eg, influenza virus) also can be transmitted by direct and indirect contact. with droplet transmission, respiratory droplets containing infectious pathogens travel directly from the respiratory tract of the infectious individual to another susceptible person through deposition on mucosal surfaces of the recipient. the distance that droplets travel depends on the velocity and mechanism by which respiratory droplets are propelled from the source, the density of respiratory secretions, environmental factors such as temperature and humidity, and the ability of the pathogen to maintain infectivity over that distance. droplets in dry air evaporate quickly, shrink in size, and fall to the ground more slowly. the changing size of a droplet affects how it responds to airflow patterns and how quickly it settles. small pressure differences, induced by natural forces such as thermal buoyancy due to air temperature differences, the wind, or mechanical fans, can generate air flows that move air from one room to another. air filtration aims to reduce airborne concentrations to well below infectious doses. in a hospital setting, patients lie in bed much of the time. the direction of an exhalation jet from a standing or seated person and that from a lying person can be different (eg, the latter may face up). the upward thermal plume generated by a standing or seated person is much stronger than that generated by a lying person. thus, some differences between the behaviors of breathing flows in hospital and other indoor environments are expected. the exhalation jet from a lying patient can behave differently in different ventilation systems, and also can be affected by other factors, such as the mode of contaminant release and the thermal plume generated by the human body or other heat sources. understanding breathing flows from a patient lying supine with different ventilation systems is useful for developing an effective ventilation method for minimizing the risk of cross-infection via airborne transmission. droplet nuclei ,5 mm in diameter exhibit a settling velocity of ,1 m/h (88 feet per minute in still air, and can follow the exhalation flows as well as the ambient air flows in a hospital ward. clinically applicable distinctions are made between short-range airborne infection routes (between individuals, generally ,1 m apart) and long-range routes (within a room, between rooms, or between distant locations, generally distances .1 m). fennelly et al 15 small droplets also may participate in short-range transmission, but they are more likely than larger droplets to evaporate to become droplet nuclei and then be considered to have the potential for long-range airborne transmission. true long-range aerosol transmission becomes possible when the droplets of infectious material are sufficiently small to remain airborne almost indefinitely and to be transmitted over long distances. pathogens that are not transmitted routinely by the droplet route can be dispersed into the air over short distances. for example, as reported by bassetti et al, 17 although staphylococcus aureus is most commonly transmitted by the contact route, viral upper respiratory tract infection has been associated with increased dispersal of s aureus from the nose into the air over a distance of 4 feet under both outbreak and experimental conditions, known as the ''cloud baby'' and ''cloud adult'' phenomena. once infectious droplets are released, the main factors that determine how they move are their size and the airflow patterns that carry them around. droplet size changes with time, depending on the environmental conditions. droplets in dry air evaporate quickly, shrink in size, and fall to the ground more slowly. the changing size of a droplet affects how it responds to airflow patterns and how quickly it settles. movement of people in a room plays a significant part in disturbing airflow and also in transporting infected air from one place to another. thus, room airflow is governed primarily, but not solely, by mechanical ventilation. other influences include temperature, humidity, movement of personnel and patients, and equipment. the varying combinations of these factors make the route and suspension time of an infectious particle very difficult to predict in a dynamic, real-world environment of a health care facility. measles and chickenpox (vzv) are both lipidenveloped and sensitive to changes in temperature, relative humidity (rh), and uv radiation. according to cox, 18 stephenson et al, 19 and ijaz et al, 20 viruses without a lipid envelope (eg, poliovirus) generally survive longer at high rh (.50%), but lipid-enveloped viruses (eg, influenza, lassa fever virus, human coronavirus [hcv] 229e) survive longer in low rh (,50%). [18] [19] [20] data on hcv 229e indicate that when airborne, this virus has a survival half-life of about 3 hours at an rh of 80%, 67 hours at an rh of 50%, and 27 hours at an rh of 30% at 20 8c, suggesting that high rh (.80%) is most detrimental to the survival of this coronavirus. bean et al 21 reported that influenza can survive for 24-48 hours on hard, nonporous surfaces such as stainless steel and plastic, but for less than 8-12 hours on cloth, paper, and tissues. in addition, influenza virus can survive for up to 5 minutes on hands, and can be transferred to hands from these nonporous surfaces for 24 hours and from tissues for 15 minutes. 21 more recently, lai et al 22 demonstrated that sars cov can survive in alkaline diarrhea stools for up to 4 days and can remain infectious in respiratory specimens for more than 7 days at room temperature. similarities with other viruses of nosocomial importance (eg, other rna lipid-enveloped respiratory viruses, such as influenza) suggest that such organisms can survive long enough in aerosols to cause disease, especially when associated with biological fluids such as mucus, feces, and blood. this sensitivity to environmental conditions also might help explain the seasonality of some viral infections. regarding influenza transmission, brankston et al 23 concluded that natural influenza transmission in humans occurs via droplets and contact over short distances as opposed to long distances. although none of the studies that they reviewed could specifically rule out airborne transmission, the authors believed that the airborne route is neither the predominant mode of transmission nor a frequent enough occurrence to be of significant concern when considering control measures for most clinical settings. 23 a recent epidemiologic investigation confirmed their conclusions. 24 a recent systematic review by li et al 25 demonstrated that adequate or inadequate ventilation has an effect on the risk of infection via infectious aerosols. an inefficient ventilation system causes the spread of airborne disease, whereas an efficient ventilation system can help mitigate the spread of infectious particles and thereby reduce transmission of disease. 25 even before the 2003 sars epidemic, there was strong evidence that ventilation and building finishes are important determinants of the nosocomial transmission of tuberculosis. according to the centers for disease control and prevention's (cdc) guidelines for environmental infection control in health-care facilities, only tb, measles (rubeola virus), and chickenpox (vzv) should be considered ''true'' airborne infectious diseases. 26 however, other infectious agents, such as sars cov, are sometimes called ''opportunistic,'' because they might be transmissible over short distances (eg, 1-2 m), given a favorable environment. 14 all viruses and almost all bacteria (excluding spores) are vulnerable to moderate levels of uvgi exposure, but the magnitude of the effect is extremely species-dependent. 27 spores, which are larger and more resistant to uvgi than most bacteria, can be effectively removed through high-efficiency air filtration without uvgi. some ugvi systems are installed in conjunction with high-efficiency filtration. this combination design can be very effective against biological agents in certain situations. smaller microbes that are difficult to 38 reprinted with permission. 5 filter out tend to be more susceptible to uvgi, whereas larger microbes, such as spores, which are more resistant to uvgi, tend to be easier to filter out (fig 1) . 29 a recent taiwanese study found that the effectiveness of uvgi depends strongly on the type of virus nucleic acid, and that viruses with dsrna or dsdna are significantly less susceptible to uv inactivation. 30 for 90% airborne virus inactivation, the uvgi dose was approximately 2-fold higher for dsrna and dsdna viruses than for ssrna and ssdna viruses. the microorganism susceptibility factor was the highest for the viruses, similar to that for fragile bacteria, but 13-20 times higher than that for endospore bacteria or fungal spores. the susceptibility factor for the viruses was higher at 55% rh than that at 85% rh, possibly because under high rh, water adsorption onto the virus surface might provide protection against uv-induced dna or rna damage. 30 supplemental control uvgi has been used as a supplement to mechanical ventilation to inactivate airborne infectious agents to protect the health of building occupants. upper-room uvgi installations are frequently used to provide ach equivalent or effective (e-ach) to that recommended by the cdc for aiirs. however e-ach is not acceptable for meeting cdc recommendations as a primary environmental control against m tuberculosis. uvgi generally refers to a uv wavelength of 253.7 nm (uv-c). exposure to uv light at this wavelength is a practical and cost-effective method of inactivating airborne viruses, mycoplasma, bacteria, and fungi on clean surfaces. 31 the most widely used application of uvgi is in the form of passive upper-room fixtures containing uvgi lamps that provide a horizontal layer of uv energy field above the occupied zone. these fixtures are designed to inactivate bacteria that enter the upper irradiated zone, and their efficacy is highly reliant on, among other factors, the airflow field conditions in the room. the survival probability of bacteria exposed to uv irradiance depends on the susceptibility of the target microorganism and the dose and duration of uv-c to which it is exposed. 32 lamps used to produce uv-c are located relatively high up in the room (8 ft), to prevent exposure to occupants by a specially designed fixture. there are two basic designs: a ''pan'' fixture with uvgi unshielded above the unit to direct the irradiation upward, and a fixture with a series of parallel plates that direct the irradiation outward while preventing the light from reaching the eyes or unprotected skin of the room's occupants. germicidal activity is dependent on air mixing via convection between the room's irradiated upper zone and the lower patient care zones. 32 this was confirmed in an investigation by miller et al 4 that involved installation of upper-room uvgi units and evaluation of these units' impact on culturable airborne bacteria. more than 90% of the bacteria detected were inactivated; however, the rate was lower for more-resistant bacteria and fungal spores. that investigation also clearly demonstrated that room air must be mixed for uvgi to effectively inactivate microorganisms. when warm air entered the room via a duct close to the ceiling (which can occur in the winter when the heating system is turned on), the warm air simply ''rested'' on the much cooler air below, and the efficacy of the uvgi system was dramatically diminished because the microbes did not move up for exposure to the uv-c irradiation. no mixing fans were turned on during the experiment, but moderate ventilation was present. the cleanliness of uv light bulbs and age of uv lamps should be checked periodically (approximately every 6 months) to ensure sufficient uv light intensity for germicidal activity (uv-c). the intensity of germicidal wavelength light decreases with age, and bulb ratings (hours of use) may vary by manufacturer. 13 upper-room uvgi is often seen as a cost-effective measure to supplement the general ventilation system in a room; however, the combination of the general ventilation system and uv lamps might not necessarily be implemented correctly within a room. for example, if the ventilation rate is too high, the particles may not be sufficiently exposed to the uv-c irradiation to ensure complete inactivation, or if the ventilation system does not provide good mixing within the room, airborne particles containing microbes might not even be exposed to the uv-c irradiation. 13 a well-designed upper-room uvgi system may effectively kill or inactivate most airborne droplet nuclei containing mycobacterium spp if designed to provide an average uv fluence rate (ie, irradiance from all angles that is incident on a small region of space; a more accurate term than ''uv dose'') in the upper room in the range of 30-50 mw/cm 2 , provided that the other criteria stipulated in the cdc's tb guidelines are met. 2 the fixtures should be installed to provide as uniform a uvgi distribution as possible in the upper room. 5 schafer et al 33 developed a method to measure fluence rate and used it to verify that this rate varied as much as 3-fold in a typical room, depending on proximity to the lamp, and found that lamp failure was common. this reinforces the need to monitor the efficacy of the lamps used in uvgi fixtures. under experimental laboratory conditions with mechanical ventilation rates of up to 6 ach, the rate at which microorganisms are killed or inactivated by uvgi systems appears to be additive with mechanical ventilation systems in well-mixed rooms. 2 for other infectious agents, such as sars-cov and influenza, the mode of transmission is by droplets, which do not remain suspended in air for long periods of time, but fall out within a 2-m radius from a coughing/sneezing person. even the most robust hvac system is unlikely to achieve sufficient air mixing to provide efficient kill of microbes transmitted by droplets. these particles never reach the upper-room uv zone; thus, an alternate method of disinfection is needed. 34 escombe et al 35 recently investigated impact of upward-facing uv light fixtures installed in ceilings of a negative-pressure tb isolation ward and ceilingmounted air ionization fixtures in an animal enclosure chamber, using a guinea pig air sampling model that involved exposure of the animals to exhaust air from the isolation ward. with this animal model, 35% of controls exposed to untreated exhaust air from the tb ward developed tb infection, whereas frequency was reduced to 14% and 9.5% with use of an ionizer and uvgi, respectively. they concluded that ''provided there is adequate mixing of room air, an upper-room uvgi fixture is an effective, low-cost intervention for use in tb infection control in high-risk clinical settings.'' 35 critical factors that affect the efficacy of uvgi include temperature, rh, and lamp output. a number of studies have indicated that the effectiveness of upper-room uvgi systems decreases as humidity increases. for optimal efficiency, rh should be controlled to 60% or less when upper-room uvgi systems are installed. temperature should be kept between 688f and 75 8f (20 8c-24 8c). both of these suggestions are consistent with 2010 facility guidelines institute (fgi) and the american society of heating, refrigerating, and air-conditioning engineers (ashrae) recommendations in ashrae standard 170 (now part of the fgi guidelines standards). 36 the ashrae handbook also provides comprehensive recommendations for installation and operation of uvgi systems. 37 experimental upper-room uvgi systems used in rooms with aerosolized bacteria (including surrogates of m tuberculosis) have shown that the higher the uv fluence rate produced in the upper air of a room, the greater the effectiveness of the system. 4, 38, 39 based on the results of experiments with upper-room uvgi systems and aerosolized bacteria in bench-scale reactors, it is apparent that the greater the uv fluence rate in the irradiated zone, the more effective the system. 40, 41 however, there appears to be an upper threshold after which an increase in uvgi does not directly correspond to an increase in the system's ability to kill or inactivate microorganisms. 4, 13, 42, 43 miller et al 4 reported decreased effectiveness of the uvgi system when the uv fixtures were placed on only one side of the room. this is consistent with the findings of riley and permutt, 44 who reported that a wider distribution of low-irradiance uv lamps was more efficient compared with the use of one centrally located high-irradiance uv lamp. this suggests that upperroom uvgi systems should be installed to provide the most uniform uvgi distribution in the upper air possible. in most of the studies that form the basis of the irradiance guidelines, the bacteria studied were primarily single cells aerosolized in deionized water. this lack of a mucus coating could possibly make these bacteria more sensitive to uvgi compared with bacteria in droplet nuclei from an infected host. 45 the killing or deactivation of 63% of droplet nuclei in a room by uvgi is equivalent to 1 ach in terms of reduced total droplet nuclei concentration in the room. 3 this reduction of droplet nuclei by a method other than mechanical ventilation is termed each. uvgi lamps can be installed in a various locations in a hvac system. one possible location is inside the ahu, typically in front of the cooling coils and drip pan. there are anecdotal reports that this configuration results in energy conservation and maintenance cost savings, but more rigorous study is needed to reproduce and validate these claims. some manufacturers of these systems have also made claims of reduced incidence of health care-associated infections (hais) with the use of uvgi in ahus. to date, however, there is little, if any, supportive evidence in the peer-reviewed scientific literature. many of the published investigations rely on environmental surface or air sampling cultures or laboratory-based animal studies for inferential support. our assessment of the available literature indicates claims of reduced hais from ahu-installed uvgi in health care facilities remain unfounded. there is some evidence of fewer complaints related to indoor air quality in buildings with systems containing uvgi inside the ahu. 46 levetin et al 47 provided some evidence for this by demonstrating a significantly lower concentration of fungal spores on a floor of a building with an in-duct uvgi system compared with a floor in the same building without such a system. the spores recovered in the building were the same as from insulation material in the ventilation ducts, however. the authors concluded that few spores from the outdoors passed through filters in the ahus, but that the spores developed when the hvac system was turned on and off. notably, they noted that ''as a result, we cannot say that the uv-c radiation had a direct effect on spores in the air stream. the effectiveness of uv-c lamps seemed to be localized, because visual inspection indicated there was conspicuous fungal growth in the downstream duct insulation lining.'' 47 uv lamps also can be placed inside supply or return air ducts to disinfect the air before it is supplied to an occupied space or when recirculated. uv irradiation by itself does not clean air. the microorganisms are still there, and in the case of some microorganisms, might still contain the ability to cause noninfectious (eg, allergenic) disease. although uv potentially can destroy allergenic sites on the surface of a bioaerosol, this ability has yet not been documented or quantified. 47 bacterial inactivation studies using bacillus calmette-guérin (bcg; a strain of mycobacterium bovis) and serratia marcescens have estimated the effect of uvgi as equivalent to 10-39 ach. 34 however, another study suggested that uvgi may result in fewer equivalent ach in the patient-care zone, especially if the mixing of air between zones is insufficient. 48 the use of fans or hvac systems to generate air movement and good mixing might increase the effectiveness of uvgi by ensuring exposure of airborne microorganisms to the light energy for a sufficient length of time. 35 uvgi has been used for disinfection of water, but that application is not addressed in this review. it has also been used to disinfect surfaces. one study found that the effectiveness of this application is limited by the low penetrating power of uvgi, and thus it is currently limited to decontaminating surfaces when conventional methods, such as the use of liquid chemical disinfectants, are not feasible. 31 some studies also have explored disinfection of medical devices and other high-frequency touch surfaces. sweeney and dancer 49 found that uvgi disinfection of computer keyboards without mechanical friction from cleaning had no impact on bioburden for 72% of the 68 keyboards in their study, and concluded that physical cleaning is of greatest importance before the use of uvgi. kac et al 50 found that uvgi effectively disinfected endocavitary ultrasound probes, but only if used in combination with a surface disinfectant applied with a cloth and with mechanical friction. interestingly, both of these investigations highlight the adjunctive impact of uvgi following traditional cleaning and disinfection for medical devices and other surfaces, whivch is consistent with use of uvgi for disinfection of air. more recently rutala et al 51 presented unpublished results of their study of ''no-touch'' full room disinfection with an automated, portable uv-c device that uses mirrors to ''bounce'' uvgi around a room to reach all surfaces, including those not directly exposed to fluence. they reported substantial log reductions in vegetative bacteria (3) (4) within 15 minutes of exposure and in spore-forming bacteria, such as c difficile (2-3), after 50 minutes of exposure. an analytical model for evaluating the uv dose in steady-state conditions using the eulerian system was proposed by memarzadeh et al. 48 computational fluid dynamics (cfd) was used to study the efficacy of inactivation of airborne bacteria by upper-room uvgi in a test room. several uv lamp configurations were used in the model. compared with available experimental data, the proposed model closely predicts the percentage of particles inactivated by uvgi. the proposed model was used to study the effects of ventilation flow rate and uv fixture configuration on inactivation of airborne bacteria in a test chamber. the lagrangian system model was also applied in the same test chamber for a similar scenario. this cfd model demonstrates that the percentage of uvgi inactivation is higher when the ventilation flow rate is lower. increasing the ventilation flow rate from 2 to 6 ach reduces the residence time of a pass through the uv zone from 24.7 to 8.3 seconds. in the latter case, the dosage is then only˜35% of the total dose received in the former case. for upper-room uvgi to be effective, the aerosolized infectious particles must be moved from the lower part of the room, where they are produced by a person coughing or sneezing, to the germicidal zone in the upper room. practical considerations prohibit the ideal situation of uvgi cleansing of all infectious particles in a single pass when they move through the upper-room uvgi zone. another consideration is how rapidly microorganisms proceed through the uvgi zone. a higher frequency of ach limits the exposure time of the infectious particles to the uvgi and thus is likely to have less effective antimicrobial activity. in practice, the effectiveness of a uvgi installation is determined by the following factors: d fixture used to house the uv-c lamp. this determines how much of the radiation discharged from the uv lamp is actually emitted from the fixture and how it is distributed. d environmental sustainability issues. most uv-c lamps use low-pressure mercury, have a limited life span, and require environmental precautions for disposal. d distance from the uv-c lamp. the distance of airborne infectious agents from the fixture will determine the irradiance level and thus the germicidal efficacy. d airflow pattern. this affects how long the bacteria and viruses are exposed to the uv radiation. d humidity. the humidity of the atmosphere is key, because water makes the infectious agent less susceptible to damage from uv radiation. the higher the rh, the less likely an aqueous aerosol will dry out. for maximum effectiveness of uvgi, rh should be ,75%. 34 according to an american biological safety association position paper, biological effects in humans from overexposure to uv-c radiation vary with wavelength, photon energy, and duration of exposure. 52 in general, adverse effects are limited to the skin and eyes. erythema (eg, reddening of the skin, as in sunburn) is the most commonly observed skin effect. chronic exposure to uv radiation can accelerate the skin aging process and increase the risk of skin cancer. the national toxicology program (ntp) classifies uv-c as a probable human carcinogen. excessive exposure to uv-c radiation can adversely affect the eyes, causing photokeratitis and/or conjunctivitis. based on the current guidelines, repeated exposure at or below the current guideline would not be expected to cause adverse health effects; however, it should be emphasized that uv radiation has been implicated in both skin cancer and cataracts in humans. on may 18, 2007, niosh received a request from the director of environmental affairs at brigham and women's hospital (bwh) in boston, massachusetts. some bwh orthopedic surgical staff members were concerned about unspecified skin and eye symptoms, which they attributed to germicidal uv-c radiation produced by ceiling-mounted uvgi lamps in orthopedic operating rooms (ors). the use of uvgi in orthopedic ors was investigated by the occupational safety and health administration (osha) on january 19, 2007 , in response to a formal complaint submitted after staff discovered that the uvgi lamp controls in an or had been tampered with and set at an inappropriately high setting. after an inspection, osha recommended that bwh provide annual uv-c and personal protective equipment (ppe) training and medical screening for all affected employees, as well as ensure that all affected employees use the required ppe. in july 2008, bwh moved the orthopedic operating suite to an area equipped with laminar airflow and discontinued the use of uvgi for intraoperative infection control. niosh investigators recommended the use of alternative infection control technologies, such as laminar airflow. 53 the use of direct uvgi as an air-cleaning method for intraoperative infection control is a relatively uncommon application that has been used by some surgeons since the 1930s. [54] [55] [56] some evidence suggests that the use of uvgi in this manner might reduce the incidence of surgical site infections by minimizing intraoperative levels of airborne bacterial contaminants. this design differs from upper-room devices in that the uv-c irradiation is directed down to expose the entire or. eye protection and other attire are required for those in the or. the relative efficacy of direct uvgi on intraoperative air quality and prevention of infection has not been well defined, however, because studies that have examined its use did so at a variety of uv intensities in association with other infection prevention methods and surgical techniques. in addition, most studies have been observational, before-after investigations, which are limited by biases and other confounding variables. investigators have reported that uvgi is usually used not alone, but rather in conjunction with laminar airflow or body exhaust techniques, with discrepancies in wound rates under the same conditions. 56 the cdc recommends against using uvgi to prevent surgical site infections. 26 overall, for general ventilation effectiveness, there is little advantage to increasing the effectiveness of the uvgi beyond 4-6 ach. uvgi is effective when at low ach, and its efficacy diminishes as ach increases, because the kill rate is dependent on the duration of exposure to the uv dose. with high ach, exposure time is significantly decreased. for personnel safety, niosh strongly encourages employers to protect employees using a hierarchy of controls approach. the objective of this approach is to minimize the risk of failure of preventive measures, resulting in a hazardous exposure. according to the hierarchy, initial efforts should be made to eliminate the hazardous agent or source of exposure. with regard to intraoperative uvgi use, this could be achieved by substituting other infection prevention methods or technologies, such as vertical laminar air flow, before implementing direct uvgi inside the or. 53 it should be noted that a more recent design for the or uses nonaspirating diffusers with unidirectional airflow over the surgical site but at lower velocities than traditional high-velocity laminar sir flow, thereby minimizing the risk of hypothermia. this design is now required in the 2010 fgi guidelines 36 and is described in detail elsewhere. 57 given the foregoing discussion, we recommend that uvgi system designers take the following considerations into account: d apply safety factors to their designs, particularly as they depart from operating modes for which they have performance data and field experience. d know the actual lamp output under the most challenging operating conditions. d avoid relying solely on design equations to determine the performance of their systems. actual testing with the contaminants of interest is highly recommended. d view claims regarding uvgi systems' high level of inactivation of pathogenic bioaerosols with caution. whereas the microbiological science underlying these conclusions applies to pathogenic bioaerosols as well as environmental organisms, much greater caution is required in the former case. it would be irresponsible to claim a high inactivation rate for a pathogenic bioaerosol without substantial testing. even with substantial testing, design failures may occur. although many laboratory studies have been conducted to analyze the efficacy of uvgi for numerous microorganisms in a range of temperature and humidity conditions, little has been done to evaluate the practical application of uvgi in health care buildings. 3 in fact, beggs et al 58 concluded that ''the knowledge base that exists on uvgi and its application is relatively small, and health care authorities have few guidelines on which to make decisions.'' as discussed earlier, potentially infectious droplet nuclei emitted from an infected host might be coated with mucus and consist of more than one bacterium. study bacteria, aerosolized in deionized water and lacking a mucus coating, may be more sensitive to uvgi compared with bacteria in droplet nuclei from an infected host. 44 installation and maintenance uvgi is associated with human health risks and unpredictable results. uv rays can cause harm to building occupants if not properly installed and maintained. installation techniques widely vary among manufacturers and currently are not regulated by a governing body to ensure proper efficacy of uvgi after installation. uvgi lamp manufacturers (eg, philips pld), acknowledge that some important information is not available. for example, regarding to the sizing of uv lamps for installation in ductwork systems, a philips technical document on uv disinfection states that ''in the calculation.it should be emphasized that it results only in a rough estimation; we did not incorporate the possible effects of humidity and temperature on the killing rate. philips is not a specialist in that field; we always advise to contact qualified authorities to evaluate the bacteriological aspects.'' 59 the use of cfd models and improved distribution studies on uvgi lamps and fixtures is moving the industry in the right direction. the cfd models characterize the room and air distribution in coordination with any uvgi systems applied within the space to evaluate the effectiveness quantitatively. 3 for uvgi applications in ahu and ductwork, maintenance personnel may be at increased risk even if their exposure time to the uvgi irradiation is short, because they will be in close proximity to the uvgi source. service personnel and occupants are at risk without special care measures. service staff need to ensure that the system is turned off when working. the need to wear protective clothing and eyewear should be stressed to prevent any possibility of harm to workers. room occupants may be exposed to higher doses of uvgi irradiation if the fixtures are not located or installed properly within the space. health care providers are at a greater risk because they occupy the space for longer periods than most patients. uvgi overexposure has the potential to cause unpleasant eye and skin irritations; however, these effects appear to be temporary and have involved no known long-term consequences to date. 60 additional areas of research needed to determine the most effective upper-room uvgi systems include uvgi measurements, air mixing, the effect of low humidity, microbial sensitivity, and testing and validation of upper-room uvgi systems. more research is also needed on the ability of uvgi systems to kill or inactivate microorganisms in respirable droplet nuclei of variable sizes and droplet nuclei coated with actual or simulated sputum. 5 methods for determining whether existing room air mixing is sufficient for uvgi effectiveness are needed, and research should explore whether the use of mixing fans has a negative impact on the intended design of the mechanical ventilation systems or a negative impact on other infection control measures. there is some indication that low rh (,25%) might adversely affect the ability of uvgi systems to kill or inactivate airborne bacteria. additional research is needed in this area. research in full-scale rooms to better ascertain the effects of high humidity (eg, 80% rh) on airborne microorganisms is needed as well. experimental research has indicated that mechanical ventilation of up to 6 ach does not have a significant effect on the effectiveness of upper-room uvgi systems; studies are needed to examine whether mechanical ventilation .6 ach decreases the effectiveness of upper-room uvgi systems. tests to determine the relative sensitivity of microorganisms to uvgi are not standardized among laboratories. laboratory testing guidelines are needed to ensure that these tests are reproducible and reflect real-world situations. laboratory tests of the efficacy of uvgi upper-room systems should be standardized as well. protocols for testing and validating upper-room uvgi systems are needed to ensure that the systems perform as designed. 1 guidelines are needed to determine the most practical method for planning effective uvgi systems in a variety of rooms or areas. theoretically, cfd modeling can be used to evaluate many of the variables associated with installing an upper-room uvgi system and provide an estimate of the uvgi dose received by droplet nuclei. experiments involving photoreactivation of microorganisms in full-scale test rooms should be conducted, as should tests of the effectiveness of uvgi on airborne bacteria over a wide range of temperatures. in real-world situations, potentially infectious droplet nuclei will vary in size and may be coated with sputum. both of these factors can decrease the effectiveness of uvgi. although some laboratory research has been done to evaluate these parameters, 34, 44, 61 more work is needed to further characterize microbial susceptibility to uvgi based on the size of respirable (up to 5 mm) droplet nuclei and droplet nuclei coated with actual or simulated sputum. data for real-world applications as this and previous literature reviews have shown, although numerous studies address the efficacy of uvgi, there remains a lack of definitive epidemiologic data demonstrating that these systems prevent hais endemic to health care facilities. also lacking is objective, reproducible evidence of improved energy efficiency of coils and fans with uvgi systems installed in ahus. the efficacy of an upper-room uvgi application depends strongly on sufficient exposure of microorganisms to uv-c, which can occur if there is good mixing of upper and lower air in the room or area where installed. furthermore, there are many marketing claims suggesting that such systems, as well as mobile systems, will protect occupants against emerging diseases such as sars cov, influenza, m tuberculosis, and bioterrorism agents. these claims have not been substantiated by the existing data, however, and must be weighed against the many variables discussed in this literature review. for tb, there is ample laboratory and reasonable evidence from animal studies, but the key question remains the relative role of uvgi in the context of the hierarchy of controls to prevent health care-associated tb. some of the agents that might be used for bioterrorism, such as anthrax spores, are not very susceptible to uv-c. because the clinical effectiveness of uv systems may vary, uvgi is not recommended for air management before air recirculation from airborne isolation rooms. it also is not recommended as a substitute for hepa filtration, local exhaust of air to the outside, or negative pressure. the use of uv lamps and hepa filtration in a single unit offers only minimal infection control benefits over those provided by the use of a hepa filter alone. duct systems with uvgi are not recommended as a substitute for hepa filters when the air from isolation rooms must be recirculated to other areas of the facility. regular maintenance of uvgi systems, involving keeping the bulbs free of dust and replacing old bulbs as necessary, is crucial. safety issues associated with the use of uvgi systems are described in guidelines. when uvgi units are required for air cleaning, as demonstrated by a risk assessment of the aii area, the units should be installed in the exhaust air ducts of the hvac system to supplement hepa filtration. when uvgi is used as a supplemental engineering control, fixtures should be installed on the wall near the ceiling or suspended from the ceiling as an upper-air unit, in the air-return duct of an aii room, or in designated enclosed areas or booths for sputum induction. in summing up the role of uvgi in today's health care facilities, uvgi should continue to be viewed not a routine replacement for ventilation, but rather as a supplement when needed under the conditions and parameters described in this review. it does not appear to have a role in the or, where air changes are well above 4-6 ach, or in properly designed aii rooms. many questions remain regarding how to achieve a balance between utility and safety; hopefully, the necessary research will continue. uvgi design basics for air and surface disinfection guidelines for preventing the transmission of mycobacterium tuberculosis in health-care settings guidelines for the application of upper-room ultraviolet germicidal irradiation for preventing transmission of airborne contagion. part ii: design and operation guidance efficacy of ultraviolet irradiation in controlling the spread of tuberculosis. niosh final report, contract 200-97-2602; ntis publication pb2003-103816 national institute for occupational safety and health. environmental control for tuberculosis: basic upper-room ultraviolet germicidal irradiation guidelines for healthcare settings update: influenza activity-united states emergence of new forms of totally drug-resistant tuberculosis bacilli: super extensively drug-resistant tuberculosis or totally drugresistant strains in iran disinfection of acinetobacter baumannii-contaminated surfaces relevant to medical treatment facilities with ultraviolet c light analysis of antibiotic resistance genes in multidrug-resistant acinetobacter sp isolates from military and civilian patients treated at the walter reed army medical center prevalence and antibiotic susceptibility of acinetobacter baumannii, pseudomonas aeruginosa and klebsiella pneumoniae in estonian intensive care units in comparison with european data guidance for control of infection with carbapenem-resistant or carbapenemase-producing enterobacteriaceae in acute care facilities complete restriction of fluoroquinolone use to control an outbreak of clostridum difficile infection at a community hospital assessing the efficacy of ultraviolet germicidal irradiation and ventilation in removing mycobacterium tuberculosis available from airborne transmission of communicable infection: the elusive pathway cough-generated aerosols of mycobacterium tuberculosis: a new method to study infectiousness dispersal of exhaled air and personal exposure in displacement ventilated rooms dispersal of staphylococcus aureus into the air associated with a rhinovirus infection the microbiology of air effect of environmental factors on aerosol-induced lassa virus infection survival characteristics of airborne human coronavirus 229e survival of influenza viruses on environmental surfaces survival of severe acute respiratory syndrome coronavirus transmission of influenza a in human beings lack of airborne transmission during outbreak of pandemic (h1n1) 2009 among tour group members, china role of ventilation in airborne transmission of infectious agents in the built environment: a multidisciplinary systematic review guidelines for environmental infection control in healthcare facilities: recommendations of cdc and the healthcare infection control practices advisory committee (hicpac) the importance of bioaerosols in hospital infections and the potential for control using germicidal ultraviolet irradiation feasibility study of germicidal uv lamps for air disinfection in simulated patient care rooms federal emergency management agency. chemical, biological, and radiological measures inactivation of virus-containing aerosols by ultraviolet germicidal irradiation department of the army. safety standards for microbiological and biomedical laboratories new research identifies a methodology for minimizing risk from airborne organisms in hospital isolation rooms method for estimating ultraviolet germicidal fluence rates in a hospital room influence of relative humidity on particle size and uv sensitivity of serratia marcescens and mycobacterium bovis bcg aerosols upper-room ultraviolet light and negative air ionization to prevent tuberculosis transmission american society of heating, refrigerating, and air-conditioning engineers. ventilation of health care facilities. ansi/ashrae/ashe standard 170 american society of heating, refrigerating, and air-conditioning engineers. ultraviolet lamp systems evaluation of a methodology for quantifying the effect of room air ultraviolet germicidal irradiation on airborne bacteria ultraviolet susceptibility of bcg and virulent tubercle bacilli effects of relative humidity on the ultraviolet-induced inactivation of airborne bacteria effect of relative humidity on the inactivation of airborne serratia marcescens by ultraviolet radiation a quantitative method for evaluating the germicidal effect of upper room uv fields ultraviolet radiation and the control of airborne contamination in the operating room room air disinfection by ultraviolet irradiation of upper air: air mixing and germicidal effectiveness size and uv germicidal irradiation susceptibility of serratia marcescens when aerosolized from different suspending media effect of ultraviolet germicidal lights installed in office ventilation systems on workers' health and well being: double-blind multiple crossover trial effectiveness of germicidal uv radiation for reducing fungal contamination within air-handling units analysis of efficacy of uvgi inactivation of airborne organisms using eulerian and lagrangian approaches can hospital computers be disinfected using a hand-held uv light source? evaluation of ultraviolet c for disinfection of endocavitary ultrasound transducers persistently contaminated despite probe covers room decontamination by ultraviolet radiation position paper on the use of ultraviolet lights in biological safety cabinets uv-c exposure and health effects in surgical suite personnel: health hazard evaluation report ultraviolet radiation and ultraclean air enclosures in operating rooms: uv protection, economy, and comfort infection control practices to reduce airborne bacteria during total knee replacement: a hospital survey in four states ultraviolet lighting during orthopaedic surgery and the rate of infection current views of healthcare design and construction: practical implications of safer, cleaner environments the resurgence of tuberculosis in the tropics. an engineering approach to the control of mycobacterium tuberculosis and other airborne pathogens: a uk hospital-based pilot study defining the effectiveness of uv lamps installed in circulating air ductwork uv air cleaners and upper-room air ultraviolet germicidal irradiation for controlling airborne bacteria and fungal spores fundamental factors affecting upper-room ultraviolet germicidal irradiation, part i: experimental key: cord-330463-j4cf7vzs authors: sattar, syed a. title: indoor air as a vehicle for human pathogens: introduction, objectives, and expectation of outcome date: 2016-09-02 journal: am j infect control doi: 10.1016/j.ajic.2016.06.010 sha: doc_id: 330463 cord_uid: j4cf7vzs airborne spread of pathogens can be rapid, widespread, and difficult to prevent. in this international workshop, a panel of 6 experts will expound on the following: (1) the potential for indoor air to spread a wide range of human pathogens, plus engineering controls to reduce the risk for exposure to airborne infectious agents; (2) the behavior of aerosolized infectious agents indoors and the use of emerging air decontamination technologies; (3) a survey of quantitative methods to recover infectious agents and their surrogates from indoor air with regard to survival and inactivation of airborne pathogens; (4) mathematical models to predict the movement of pathogens indoors and the use of such information to optimize the benefits of air decontamination technologies; and (5) synergy between different infectious agents, such as legionellae and fungi, in the built environment predisposing to possible transmission-related health impacts of aerosolized biofilm-based opportunistic pathogens. after the presentations, the panel will address a set of preformulated questions on selection criteria for surrogate microbes to study the survival and inactivation of airborne human pathogens, desirable features of technologies for microbial decontamination of indoor air, knowledge gaps, and research needs. it is anticipated that the deliberations of the workshop will provide the attendees with an update on the significance of indoor air as a vehicle for transmitting human pathogens with a brief on what is currently being done to mitigate the risks from airborne infectious agents. i welcome you all to this multinational workshop! this workshop was conceived over a year ago, and the organizing committee ( table 1 ) formally requested that astm international (www.astm.org/) hold the event under its auspices. astm's committee e35, which deals with pesticides, antimicrobials, and alternative control agents, approved the proposal in april 2015. mounting recognition of indoor air as a vehicle for infectious agents is leading government regulators, such as the u.s. environmental protection agency, to refine and update their guidelines, 1 researchers to develop better means of studying airborne pathogens, 2 and civil engineers and architects to find innovative means of making indoor air safer while keeping energy conservation in mind. 3 although comprehensive guidelines and standardized means are available to study chemical pollutants in indoor air, 4 there remains a general lack of suitable experimental facilities and standardized protocols to quantitatively assess the survival of pathogens in indoor air and to document their removal and inactivation by physical and chemical means. this workshop will address these issues, among others. the workshop's specific objectives, therefore, are as follows: the deliberations will also focus on the development of standards for assessing indoor air decontamination technologies and government regulations for registration of products to be marketed. as noted, this workshop has been organized under the auspices and with the support of astm international. the city university of new york and the university of ottawa (canada) are the 2 academic sponsors of the workshop, and financial support has been provided by rb (montvale, nj) and microbac (sterling, va). these 2 companies are also funding publication of the workshop proceedings. we gratefully acknowledge their generous support. the organizing committee has put together an outstanding group of speakers who will offer a comprehensive yet balanced perspective on the key issues. table 2 lists the topics to be covered, along with the names and affiliations of the presenters. elsevier (www.elsevier.com) has agreed to publish the proceedings of the workshop after peer review. elsevier will also provide a preview of the proceedings, including the abstracts for each presentation, for release during the 2016 conference of the association for professionals in infection control and epidemiology. the workshop proceedings will also contain a summary of the concluding discussions. potential members of the audience include researchers in aerobiology, makers of air purification technologies, contract laboratories that assess air decontaminants, government regulators dealing with indoor air quality, and members of standards-setting organizations, such astm international (www.astm.org) and american society of heating, refrigerating, and air-conditioning engineers (www.ashrae.org). table 3 is a glossary of the common terms used throughout this workshop's presentations. this is included in an attempt to create a level playing field while facilitating the understanding of the subject matter by experts in fields other than environmental microbiology. however, the emphasis here is on working definitions, recognizing that efforts are needed to develop a more comprehensive glossary for broader applications in this area. aerobiology, the study of living organisms and their components in air, became a full-fledged scientific discipline in 1964. this was followed in 1974 by the founding of the international association of aerobiology (https://sites.google.com/site/ aerobiologyinternational/). the initial focus of this group was the study and movement of pollen, but microbes and other life forms were soon added to the mix with a corresponding broadening of the organization's scope (fig 1) . the microbiologic quality of indoor air comes under the rubric of aerobiology (fig 2) . this workshop will focus only on indoor air as a vehicle for human pathogens. indoor air quality exposure of humans to indoor air and its contents coincided with cave dwelling >200,000 years ago. 5 sharing of the human habitat with domesticated animals, such as cattle, dogs, and pigs, facilitated the rise of zoonotic infections, including airborne infections (eg, measles). 6 exposure to pathogens of humans and animals via the agency of indoor air continues to this day. although the focus here is on indoor air, indoor air is not entirely immune to what goes on outdoors. the air from outside an edifice affects the air indoors and vice versa. in fact, the use of fossil fuels for heating the indoors contributes directly and indirectly to overall climate change. an early consequence of energy conservation was sealed buildings and houses, which eventually gave rise to sick building or tight building syndrome as a result of the trapping of airborne pollutants and higher levels of moisture inside. 7 humans and animals are the main contributors of microbeladen particles indoors. in fact, individuals leave their own personal microbial footprint as a part of the indoor microbiome. 8 aerosolization of microbes from biofilms and resuspension of dust are the other principal contributors to the microbial content of indoor air (fig 3) . although the route by which airborne pathogens cause infections varies between microorganisms, improvements in the quality, quantity, and movement of indoor air can mitigate the airborne spread of many human pathogens by preventing pathogen this phenomenon is especially relevant in aerobiology because a host is often exposed to potentially harmful biologic, chemical, or physical agents simultaneously or sequentially. droplet nuclei airborne particles derived from larger droplets after loss of water such droplets are crucial for the spread of infectious agents by air as their relatively small size (0.5-5.0 μm) allows for their stability in air while also permitting their retention on inhalation. indoor air quality quality of the air within buildings and other enclosures, with particular reference to the health and comfort of the occupants the overall quality of indoor air is dependent on a mix of a variety of factors that may be site and time sensitive. the capacity of a microbe to infect a given host depends not only on its biology but also on the general health status of the host and the portal of entry into the host. a microbe capable of causing localized or generalized damage to the host please see "infectious agent." the totality of microorganisms and their collective genetic material present in or on the human body or in another environment a certain proportion of the microbes found in a microbiome may not be culturable but detected and identified via their genomes only. this term is now preferred over microflora. opportunistic pathogen a microbial pathogen capable of infecting hosts whose natural defenses are compromised because of advanced age, immunosuppression, or other underlying causes the number, variety, and health significance of such pathogens is on the rise in conjunction with the rising numbers of those debilitated by acquired or induced immunosuppression. pathogen (microbial) any microbe capable of causing damage to the host even an otherwise innocuous microbe can become pathogenic depending on the general resistance of the host or the microbe's entry into normally sterile areas of the body where it can become an opportunistic pathogen. perikairots environment-based opportunistic pathogens biofilm-based microbes such as legionellae and environmental mycobacteria can infect those debilitated because of age or underlying medical conditions. resident microbiota a mix of microbes normally found in or on the host many members of the resident microbiota from skin and mucous surfaces are frequently found in indoor air. particles small enough to access the alveolar space during normal breathing such particles may or may not contain viable microbes. surrogate microbe a microbe that resembles ≥1 type of pathogens but is safer and easier to work with in the laboratory; also called a simulant the use of such microbes is crucial in many aspects of microbiology, in general. the body's automatic inhalation and exhalation process at rest in addition to coughing and sneezing, tidal breathing can release infectious agents into the air. transient microbiota microbes temporarily acquired by a host during normal contact with the environment inhalation and reducing the microbial load on environmental surfaces. indoor air is arguably the fastest and most highly efficient means of pathogen spread in a given setting. as depicted in figure 2 , indoor air is a complex and dynamic mixture of numerous components in a constant state of flux influenced by many factors both indoors and outdoors. the quality of indoor air represents the outcome of the unique mix of components in a given setting that, in themselves, change temporally. one major challenge in preventing and controlling the airborne spread of infection is the presence of possibly multiple and mobile sources of pathogens at a given location and time. one or more infected or colonized persons or pets may contaminate the air in their immediate vicinity with exposure of those nearby without the air having reached any available means of pathogen decontamination. certain factors that influence indoor air quality may fall under the categories of chemical and physical. for example, smoke from burning wood for cooking fuel is, of course, chemical in nature, but respirable particles in the smoke are the primary means of lung irritation and potential damage leading to cardiopulmonary syndromes, including lung cancer (http://www.who.int/mediacentre/ factsheets/fs292/en/). the study of indoor air quality received a major boost as a consequence of the severe acute respiratory syndrome outbreak in 2003 9 and the anthrax scares in the united states in 2011. 10 it also spawned much interest in the development, assessment, and application of technologies to decontaminate indoor air. as shown in figure 3 , particles >10 μm in diameter entering the air may rapidly fall out of the air because of their mass under prevailing environmental conditions, particularly temperature and relative humidity, whereas smaller particles can not only remain airborne for extended periods but can also be transported readily indoors by air currents over considerable distances. respirable particles fall in the range of 0.2-5.0 μm in diameter, whereas smaller particles are generally exhaled because of the aerodynamics of breathing. the actual site of retention of the inhaled particles depends on their nominal size. it is noteworthy here that persons with respiratory infections breathe out pathogen-laden particles during tidal breathing. 11 a human adult at rest breathes in an average of 11,000 l of air per day. 12 in any given setting, one may choose not to drink the water or eat the food that is available but generally has little choice in breathing the same air as everyone else. this makes air an environmental equalizer-conferring on it the unique potential to parse out evenly whatever it may contain. further, infectious agents entering indoor air mix rapidly with no perceptible color or smell. although the potential of air to spread respiratory pathogens is well recognized, its ability to transmit enteric pathogens is not as well appreciated. airborne particles containing enteric pathogens may be retained in the tonsillar region and swallowed for relocation to the gastrointestinal tract with subsequent replication there. 13 ijaz et al 14 have provided a comprehensive list of human pathogens known or suspected to spread via indoor air. the following are the main topics to be covered during the workshop. despite the recognized significance of indoor air as a vehicle for human pathogens, there are major gaps in our understanding of how well these pathogens remain viable under different environmental conditions. such information is crucial to assessing the potential of a given pathogen to spread by air. construction of an aerobiology chamber (approximately 24 m 3 ) will be described, and data from use of the chamber to test airborne survival of staphylococcus aureus, klebsiella pneumoniae, and acinetobacter baumannii will be presented. many technologies claiming microbial decontamination of indoor air are on the market, but without proper validation of their claims. information will be presented on ways to test such technologies using standardized protocols for registration and marketing purposes. because they may not be readily available and generally are unsafe and difficult to culture in the laboratory, it is rarely possible to use actual field strains of human pathogens in testing. this necessitates the use of surrogate microbes to generate data predictive of the behavior of pathogens. however, certain surrogates that are used commonly and recommended by regulatory agencies and standardssetting organizations alike are inherently unsuitable for experimental work in aerobiology. for example, k pneumoniae, frequently used as a surrogate for airborne gram-negative bacilli, does not survive aerosolization well because it is relatively fragile and unstable in air. therefore, data generated with k pneumoniae likely will not be predictive of the behavior of actual human pathogens. this workshop will identify more suitable surrogates with supporting data. can microbial decontamination of indoor air reduce the risk for pathogen contamination of environmental surfaces? data will be presented to demonstrate that reductions in the levels of airborne microbes can indeed lead to corresponding reductions in the microbial contamination of environmental surfaces in a given setting. the use of integrated models could help analyze outbreaks, evaluate the relative importance of hygiene and infection prevention and control for policymakers, and provide guidance in environmental design for greater occupant safety and comfort. these will be illustrated using some recent examples, including severe acute respiratory syndrome, influenza, and middle east respiratory syndrome. quantitative recovery of viable microbes from air is vital in aerobiologic studies. an update will be given on available methods, including their strengths and limitations. experimentation with airborne microbes is generally quite labor intensive and costly and requires special biosafety precautions. mathematical models can assist greatly in optimizing aerobiology chamber design and in predicting the influence of furniture and other objects on the movement of microbes. data will be presented with specific reference to a chamber that fully conforms to guidance from the u.s. environmental protection agency. biofilms are not only common in the built environment, but they can be common sources of airborne pathogens. such biofilms often contain several microbial species having complex interactions between them. this will be illustrated with the example of how fungi and legionellae coexist with potential risks to human health. product performance test guidelines: ocspp 810.2500: air sanitizers-efficacy data recommendations decontamination of indoor air to reduce the risk of airborne infections: studies on survival and inactivation of airborne pathogens using an aerobiology chamber airborne spread of infectious agents in the indoor environment world health organization. who guidelines for indoor air quality: selected pollutants origins of major human infectious diseases domesticated animals and human infectious diseases of zoonotic origins: domestication time matters ventilation rates and health: multidisciplinary review of the scientific literature humans differ in their personal microbial cloud the role of super-spreaders in infectious disease secondary aerosolization of viable bacillus anthracis spores in a contaminated us senate office influenza virus in human exhaled breath: an observational study how much air do we breathe? concentration, size distribution, and infectivity of airborne particles carrying swine viruses generic aspects of airborne spread of human pathogens indoors and emerging air-decontamination technologies key: cord-307263-znuqdzdp authors: sun, niuniu; shi, suling; jiao, dandan; song, runluo; ma, lili; wang, hongwei; wang, chao; wang, zhaoguo; you, yanli; liu, shuhua; wang, hongyun title: a qualitative study on the psychological experience of caregivers of covid-19 patients date: 2020-04-08 journal: am j infect control doi: 10.1016/j.ajic.2020.03.018 sha: doc_id: 307263 cord_uid: znuqdzdp background: the coronavirus disease 2019 (covid-19) is spreading rapidly, bringing pressure and challenges to nursing staff. objective: to explore the psychology of nurses caring for covid-19 patients. method: using a phenomenological approach, we enrolled 20 nurses who provided care for covid-19 patients in the first affiliated hospital of henan university of science and technology from 20 january to 10 february 2020. the interviews were conducted face-to-face or by telephone and were analysed by colaizzi's 7-step method. results: the psychological experience of nurses caring for covid-19 patients can be summarized into four themes. firstly, negative emotions present in early stage consisting of fatigue, discomfort, and helplessness was caused by high-intensity work, fear and anxiety, and concern for patients and family members. secondly, self-coping styles included psychological and life adjustment, altruistic acts, team support, and rational cognition. thirdly, we found growth under pressure, which included increased affection and gratefulness, development of professional responsibility, and self-reflection. finally, we showed that positive emotions occurred simultaneously with negative emotions. conclusions: during an epidemic outbreak, positive and negative emotions of the front-line nurses interweaved and coexisted. in the early stage, negative emotions were dominant and positive emotions appeared gradually. self-coping styles and psychological growth played an important role in maintaining mental health of nurses. the severe acute respiratory syndrome coronavirus 2 (sars-cov-2) is a newly discovered ribonucleic acid coronavirus isolated and identified from patients with unexplained pneumonia in wuhan, china in december 2019 [1] . before it was named by the international committee of viral classification on 12 february, 2020, it was called 2019-ncov. sars-cov-2 mainly causes respiratory and digestive tract symptoms [2] , with symptoms ranging from mild self-limited disease to severe pneumonia, acute respiratory distress syndrome, septic shock, and even systemic multiple organ failure syndrome. the infection source of coronavirus disease 2019 is mainly patients with sars-cov-2 infection. asymptomatic infected patients may also become the source of infection, mainly via aerosols from the respiratory tract, but also through direct contact [3] . elderly people with underlying diseases are more likely to be infected with the virus and develop severe disease and children and infants are also at risk. at present, there are no specific drugs for this disease. the treatment and nursing mainly include antiviral and traditional chinese medicine treatment, isolation, symptomatic support, and close monitoring of disease progression [3] . since the first case of unexplained pneumonia in wuhan, 52 countries in the world have confirmed cases by 28 february according to who data, of which about 94% are in china [4] . on that day in china, there were 37,414 active confirmed cases (including 7,664 severe cases) in 31 provinces, 39,002 recovered and discharged cases, 2,835 deaths, amounting to 79,251 confirmed cases as well as 1,418 suspected cases. [5] a total of 658,587 close-proximity interactions were tracked, including 58,233 close-proximity interactions under medical observation. although china experienced sars in 2003 and h1n1 in 2009, the outbreak of covid-19 as a new infectious disease severely tested the country's public health system. in this context, medical workers, as the main force in the battle against the epidemic, bear the monumental task. unfortunately, many front-line personnel have sacrificed their own well-being and have been infected or died, which causes increasing psychological pressure. according to the chinese center for disease control and prevention, by 11 february, over 3000 health care personnel in china were suspected to be infected with sars-cov-2. among them, 1716 were confirmed cases and 5 had died [6] . previous studies have shown that during sudden natural disasters and infectious diseases, nurses will sacrifice their own needs to actively participate in the anti-epidemic work and make selfless contributions out of moral and professional responsibility [7] . at the same time, nurses would be in a state of physical and mental stress and feel isolated and helpless in the face of health threats and pressure from the high-intensity work caused by such public health emergencies [8] . previous studies have shown that when nurses are in close contact with patients with emerging infectious diseases such as sars [9] , mers-cov [10, 11] , ebola [12] , h1n1 [13] , they will suffer from loneliness, anxiety, fear, fatigue, sleep disorders, and other physical and mental health problems. studies have shown that the incidence of depression, insomnia, and post-traumatic stress among nurses involved in the treatment of sars patients was 38.5%, 37%, and 33%, respectively [14] . in a study on the psychological status of ebola patients' caregivers, 29% of respondents felt lonely and 45% received psychological counselling [15] . on the contrary, some studies also demonstrate the positive experience and growth brought by the collective anti-epidemic efforts [13, 16] . due to the sudden outbreak of the epidemic, nurses from the department of infectious diseases had to enter the negative pressure ward to care for the patients after only undergoing a brief training on covid-19. nurses from other departments were required to go through three training stages before starting nursing duties for patients with covid-19: pre-job training, adaptive training by nursing other patients in the infection department, and negative pressure ward training. this process occupied about one week. nurses who entered the negative pressure ward would work for 0.5 -3 months before being transferred to other non-anti-epidemic positions. because covid-19 is a new disease and the medical system and culture of different countries varies, further research is needed on the psychological experience of frontline nurses fighting against covid-19. currently, published studies have highlighted the disease prevalence [17] , clinical characteristics, diagnosis, and treatment [2] . some reports have paid attention to the severity of psychological problems in medical personnel [18] and the urgency of providing psychological care [19] . however, no qualitative studies have been published on the psychological experience of nurses. therefore, our study aims to understand the subjective experience of nurses participating in nursing covid-19 patients through semi-structured interviews and to analyse the data using phenomenological methods [20] , providing fundamental data for the psychological experience of nurses. our research used the colaizzi's phenomenological method to qualitatively analyse the psychological experience of nurses caring for patients with covid-19. colaizzi's phenomenological method focuses on the experience and feelings of participants and finds shared patterns rather than individual characteristics in the research subjects. this scientific approach guarantees the authenticity of the collected experience of participants to adhere to scientific standards. by using a purposeful sampling method, we selected 20 nurses caring for patients with covid-19 in the first affiliated hospital of henan university of science and technology from 20 january to 10 february 2020. the inclusion criteria included (1) nurses who entered the negative pressure ward and provided nursing care for confirmed covid-19 patients and (2) volunteers who participated in the study. the exclusion criteria were inability to conduct two or more interviews during the study period. we determined the number of required respondents by interviewing nurses who met the inclusion criteria until the data was saturated and no new topics were generated. we determined the interview outline by consulting relevant literature, seeking we communicated the purpose and significance of the study with the participant in advance and scheduled the interview time at their convenience. the interviewer possessed a master of science in nursing with experience in qualitative interview and had worked as a head nurse in the sars isolation ward and was experienced in epidemic prevention and control. with 20 years of clinical nursing, teaching, and scientific research experience and 5 years of psychological consultation experience, the researcher obtained a second level psychological consultant certificate (the highest level in china) issued by the ministry of human resources and social security of china. therefore, the researcher was able to carry out this research independently. the one-to-one interviews were conducted in a separate room in a quiet manner without interruptions. the interviews were recorded, which were kept strictly confidential. the interviews took 40 -60 minutes per person. if the participant exhibited emotional problems during the interview, adequate psychological intervention was provided to prevent secondary psychological harm. the study subjects were allowed to withdraw consent at any time. the researchers remained neutral in collecting the data and established good relationships with the participants. we used techniques such as unconditional acceptance, active listening, and clarification to promote the authenticity of the data and to avoid bias. for each participant, at least 1 -2 face-to-face interviews and 1 -2 telephone interviews were arranged as needed to ensure data collection at multiple time points. within 24 hours of each interview, the recording was transcribed and analysed by colaizzi's phenomenological analysis method. two researchers independently reviewed the interview materials, summarized and extracted meaningful statements, and formulated the themes present. conflicting opinions on the contents of a theme were discussed and resolved by a research group composed of a master of nursing, a doctor of nursing, and two chief nurses. this study was reviewed and approved by the ethics committee of the first affiliated hospital of henan university of science and technology (ethics code: 2020-03-b001). all participants signed informed consent. the authors promise that there will be no academic misconduct such as plagiarism, data fabrication, falsification, and repeated publication. in our study, we enrolled three males and 17 females between 25 to 49 with an average age of 30.60 ± 6.12. the working experience ranged from 1 to 28 years with an average of 5.85 ± 6.43. all nurses possessed a bachelor's degree. seven nurses were married with children, five were married without children, and eight were unmarried without children. there were 17 general nurses and 3 head nurses. table 1 outlines the baseline characteristics of the participants. we explored the psychological experience of caregivers of patients with covid-19 using phenomenological methods. we found four themes that are summarized below. exemplar quotes for each theme are displayed in table 2 . iv. bidirectional concerns with their own family members "i am worried that i will infect my children" "my partner is very worried that i will be infected." "i am the only child and my mother cries every day and fears that i will be infected, and i worry more about them... "i feel good using mindfulness-based stress reduction." ii. life adjustment "i feel sleep is the best stress relief, i just want to sleep." "i think eating and drinking will increase my resistance. i don't lose weight now; i eat a lot." "i am exercising less than before because the heavy workload is also exercise and the right amount is the best." iii. taking the initiative to be altruistic and seeking team support by "huddling together for warmth" "everyone is very welcoming and friendly. experienced colleagues will take the initiative to teach me. i also take the initiative to teach new colleagues." "everyone is willing to do more work so colleagues can rest more. colleagues are particularly united." "if someone is uncomfortable, everyone will take care of him and work for him." all study subjects experienced a significant amount of negative emotions in the first week, especially in the period from the first pre-job training to the first time they entered the negative pressure ward. as the number of patients continued to rise, the workload of all nurses (n = 20) increased proportionally with 1.5 -2 times normal work hours and workloads. nurses were required to conserve protective clothing by reducing the number of times they wear it since protective equipment was in short supply, resulting in fatigue and discomfort. failing to meet physical and psychological needs brought a sense of helplessness. all participants (n = 20) expressed their fears, which peaked when they entered the negative pressure ward for the first time, which then gradually declined. similarly, outsourced support nurses (n = 12) also experienced a strong sense of fear when they first entered the department of infectious diseases, but gradually eased as their work adjusted. most nurses (n = 11) expressed concerns about patients in an isolated environment with relatively few caregivers and many patients. they were mainly concerned about the unknown conditions of the patients, severe emergencies, and the patients' psychological state. as with any emerging infectious disease, work processes and nursing routines need to be explored while working. most of the participants (n = 15) felt different levels of anxiety. under the challenges of changes in working environment and team members, 50% of nurses said they felt anxious. most nurses in this study were between 25 and 40 years old. some came from a single-child family and have elderly and children in their family. all nurses expressed concern about the impact of the outbreak on the health of their families. they also said that their families were also worried about their health. those who did not live with their parents (n = 9) chose to hide the fact that they work in isolation ward from their parents. after separation from their families, they felt helpless and guilty. the nurses (n = 4) with the elderly and children at home were particularly worried of their families. all nurses (n = 20) activated psychological defence mechanisms, such as speculation, isolation, depression, distraction, self-consciousness, humour, rationalization, etc. nurses used existing knowledge and new knowledge of psychological decompression communicated by colleagues or the internet to adjust themselves and actively or passively used psychological techniques, such as writing diary and letters, breathing relaxation, mindfulness, music meditation, and emotional expression and venting. most nurses (n = 14) chose to adjust their sleep when stressed by work. some nurses will increase their food intake and some will exercise regularly and maintain physical strength to ensure normal work ability. during times of stress, nurses (n = 13) cared and helped each other and showed support for stress relief. most nurses said that they felt the collective power and the team cohesion was stronger. some nurses (n = 9) took the initiative to process information and use medical knowledge for analysis. their attitudes were calm and rational. nurses also took the initiative to compare situations, find favourable information, and encourage themselves. all participants (n = 20) mentioned their gratitude for the support from colleagues, relatives, friends, and all sectors of society. they also realised the importance of health and family. most nurses (n = 15) said that they would work and live with a state of appreciation and gratitude in the future. more than 70% of the participants mentioned that professional responsibility prompted them to participate in the mission to contain the epidemic. most nurses (n = 9) reviewed the value of the nursing profession and identified more with their chosen profession. half of the nurses (n = 10) conveyed that although the epidemic prevention work was hard, they started to self-reflect. for example, they strengthened their will, discovered their potential, and increased their courage to face life. although most nurses had negative emotions such as fear, anxiety, and worry, positive emotions appear synchronously or progressively. after a week, positive emotions prevailed in 70% of the nurses. while fear and anxiety were brought on by the epidemic, nurses also evaluated the epidemic prevention and control progress and felt confidence in the medical capability of the government and its subunits. at the same time, they felt confidence in self-prevention and control ability after training and practice. all nurses actively accepted anti-epidemic tasks and most (n = 11) volunteered. most nurses (n = 16) showed calmness when receiving these tasks. although, as mentioned earlier, there were negative emotions such as fear and anxiety in the early stages, these subsided after the pre-job training and environmental adaptation. most nurses (n = 14) said that after entering the negative pressure ward to care for patients, they felt calm and relaxed. despite difficult conditions and challenges in the fight against the disease, 60% of the nurses reported feeling happy. firstly, the nurses felt the patient's goodwill, respect, active cooperation, and gratitude. secondly, family and team support brought happiness. contact with family was a key factor in our study. in addition, the hospital has a reward and welfare system in place to support and motivate nurses. the encouragement of colleagues also brought happiness to nurses. other forms of social support were important to the nurses' feeling of appreciation. this study explored the psychological experience of caregivers of patients with covid-19 using phenomenological methods and we summarised our findings into four themes: significant amounts of negative emotions at an early stage, self-coping styles, growth under stress, and positive emotions that occur simultaneously or progressively with negative emotions. the nurses caring for covid-19 patients felt extreme physical fatigue and discomfort caused by the outbreak, intense work, large number of patients, and lack of protective materials, which was consistent with the studies on the outbreak of mers-cov [10, 21] and ebola [15] . in this study, nurses' concerns about family members were consistent with the study of lee et al. [22] , especially those with elderly and children in the family. the physical exhaustion, psychological helplessness, health threat, lack of knowledge, and interpersonal unfamiliarity under the threat of epidemic disease led to a large number of negative emotions such as fear, anxiety, and helplessness, which have been reported by several studies [8, 10, 11] . we showed that nurses' negative emotions are more pronounced in the first week when entering pre-job training and negative pressure ward for the first time. therefore, early psychological intervention is particularly important to nurses in an epidemic. it is best to conduct stress assessment and screening of nurses immediately after receiving the epidemic prevention tasks and to provide professional, flexible, and continuous psychological intervention [15, 22] to promote emotional release and improve nurses' mental health [23] . at the same time, it is important to establish early support systems [9] , such as adequate supplies of protective materials, reasonable allocation of human resources, elderly and infant care services for nurses' families, pre-job training, and interpersonal interaction among nurses to facilitate nurses' adaptation to the anti-epidemic tasks. it is known that coping style, cognitive evaluation, and social support are all mediators of stress. studies have shown that psychological adaptation and social support play an intermediary role in psychological rehabilitation under outbreak stress [24] . pressure of the epidemic may prompt nurses to use their medical and psychological knowledge to actively or passively make psychological adjustments. in our study, nurses adopted avoidance, isolation, speculation, humour, self-consciousness, and other psychological defences to psychologically adjust to the situation. it has been demonstrated that all coping measures under the epidemic disaster can alleviate stress and promote mental health [25] . participants adopted breathing relaxation, music, meditation, mindfulness, and other ways to reduce stress, which was consistent with the study of nurses in the sars wards that adopted multiple ways to deal with stress [22, 26] . in addition, our results showed active altruism and greater team solidarity, reflecting the study of kim et al. [10] and shih et al. [27] . generally, nurses can adjust their cognitive rationality to adapt to the epidemic, which may also be related to health care professionals' rich medical knowledge and more rational and positive attitude [28] . according to american psychologist richard lazarus' stress and coping model, whether the stressors are effective or not depends mainly on the process of cognitive evaluation and coping. when stressed, nurses constantly adjust cognitive evaluation through professional knowledge to promote self-psychological balance, take the initiative to be altruistic, seek team support [13] , take the initiative to reduce stress, adjust sleep, diet and exercise to adapt to internal and external environment changes, and prevent injuries caused by stress, which has positive significance for mental health [23] . many studies have shown that epidemic outbreaks can cause psychological trauma for caregivers [14, 18, 19] . in contrast, the results of our study demonstrate that most nurses grew psychologically under pressure. nurses partook in self-reflection of their own values and found positive forces such as expressing more appreciation for health and family and gratitude for social support, which was consistent with study of shih et al. [27] . the sense of responsibility brought by professional ethics in an epidemic [7, 11] encouraged nurses to actively participate in anti-epidemic tasks and boosted their professional identity and pride, in line with previous reports [16] . therefore, actively guiding and inspiring nurses to realise their own psychological growth during an epidemic may play a positive role in psychological adjustment. our finding of the existence of positive emotions in our nurses such as confidence, calmness, relaxation, and happiness, which simultaneously or gradually appeared with negative emotions, was in contrast to the results several studies that describe only the presence of a large amount of negative emotions during outbreak stress [18, 19] . however, other studies report similar findings [13, 16, 21] . in the case of an outbreak, confidence in safety, early training, and confidence in professional skills are all factors that promote medical staff's willingness to actively participate in anti-epidemic work [29] . physical and mental rewards to nurses from work units are also important supporting factors [11] . our participants generally believed that positive emotions were related to the multi-dimensional support of patients, family members, team members, government, social groups etc. therefore, social support is critical for nurses in the fight against epidemics [14, 16, 21] . the calmness and ease of most nurses in this study after starting the anti-epidemic tasks is rarely mentioned in other studies and may be related to nurses' gradual adaptation, acceptance, positive response, and personal growth [14, 26] . studies have shown that positive emotions play an important role in the recovery and adjustment of psychological trauma [30] . optimism has a protective effect on psychological trauma under disasters and can promote the psychological rehabilitation of post-traumatic stress disorder [31] . therefore, in the process of psychological intervention of nurses in an epidemic, strengthening multi-dimensional social support, adjusting cognitive evaluation, guiding positive coping styles, and stimulating positive emotions are crucial to promote the psychological health of nurses. most existing qualitative studies are retrospective studies. in contrast, this study established a good relationship of consultation and visit with the participants in an early stage when the participants just accepted the anti-epidemic tasks. we collected the psychological experience data of the participants over time through multiple interviews. this led to a deep understanding of their work experience, resulting in comprehensive and authentic data. diverging from the results of many studies on the experience of negative emotions during outbreak stress, we found that positive emotions coexist with negative emotions, as well as psychological adjustment and growth under pressure, and preliminarily discussed its impact on nurses' mental health. due to the characteristics of qualitative research, the sample size of this study was limited. firstly, most of the participants were nurses, including three nursing managers. the experiences of other health care workers and administrators besides nurses need to be further explored. secondly, due to the nature of outbreak prevention and control, we were unable to conduct focus group interviews and did not collect data from multiple centres in order to avoid potential cross-infection. in addition, this study was a short-term study. long-term experience of the research subjects would be a valuable avenue to explore in the future. this study provided a comprehensive and in-depth understanding of the psychological experience of caregivers of patients with covid-19 through a phenomenological approach. we found that during the epidemic, positive and negative emotions of frontline nurses against the epidemic interweave and coexist. in the early days, negative emotions were dominant and positive emotions appeared simultaneously or gradually. self-coping style and psychological growth are important for nurses to maintain mental health. this study provided fundamental data for further psychological intervention. a novel coronavirus from pat ients with pneumonia in china clinical features of patients infected with 2019 novel coronavirus in wuhan interpretation of pneumonia diagnosis and treatment scheme for novel coronavirus infect ion (trial version 6) who novel coronavirus(2019-ncov) situation report -39 update on pneumonia of new coronavirus infect ion as of 24:00 on china disease control report: more than 3,000 medical staff infected with new crown virus ethical and legal challenges associated wit h disaster nursing nurses' beliefs about public healt h emergencies: fear of abandonment sars: caring for patients in hong kong nurses' experiences of care for patients wit h middle east respiratory syndrome-coronavirus in south korea healt hcare worker semotions, perceived stressors and coping strategies during mers-cov outbreak sources and symptoms of stress among nurses in the first chinese ant i-ebola medical team during the sierra leone aid mission: a qualitat ive study new zealand nurses percept ions of caringfor patients with influenza a (h1n1) prevalence of psychiatric morbidit y and psychological adaptat ion of the nurses in a structured sars caring unit during outbreak: a prospect ive and periodic assessment study in taiwan the psychosocial challenges of caring for pat ients with ebola virus disease instructive messages from chinese nurses'stories of caring for sars patients the cont inuing 2019 -ncov epidemic threat of novel coronaviruses to global healt h-the latest 2019 novel coronavirus outbreak in wuhan the mental healt h of medical workers in wuhan, china dealing wit h the 2019 novel coronaviru s timely mental healt h care for the 2019 novel coronavirus outbreak is urgently needed colaizzi pf， 1978) colaizzi pf. psychological research as the phenomenologist views it working experiences of nurses during the middle east respiratory syndrome outbreak facing sars: psychological impacts on sars team nurses and psychiatric services in a taiwan general hospital nat ional healt h commission of the people's republic o f china. the guideline of psychological crisis intervent ion for 2019 -ncov pneumonia 08b966594253b2b791be5c3b9467.sht ml social support and psychological adjust ment to sars: the mediat ing role of self -care self-efficacy relat ions of sars -related stressors and coping to chinese college students' psychological adjust ment during the 2003 beijing sars epidemic the psychological impact of severe acute respiratory syndrome outbreak on healt hcare workers in emergency depart ments and how they cope the impact of the 9 -21 earthquake experiences of taiwanese nurses as rescuers knowledge, attitude and anxiet y towards pandemic flu a potent ial bio weapon among healt h professionals in indore cit healt hcare workers'willingness to work during an influenza pandemic: a systemat ic review and meta-analysis the regulatory power of posit ive emot ions in stress: a temporal funct ional approach effects of optimism on recovery and mental healt h after a tornado outbreak key: cord-326887-lyewg2c9 authors: bloomfield, sally f.; aiello, allison e.; cookson, barry; o'boyle, carol; larson, elaine l. title: the effectiveness of hand hygiene procedures in reducing the risks of infections in home and community settings including handwashing and alcohol-based hand sanitizers date: 2007-12-10 journal: am j infect control doi: 10.1016/j.ajic.2007.07.001 sha: doc_id: 326887 cord_uid: lyewg2c9 infectious diseases (id) circulating in the home and community remain a significant concern. several demographic, environmental, and health care trends, as reviewed in this report, are combining to make it likely that the threat of id will increase in coming years. two factors are largely responsible for this trend: first, the constantly changing nature and range of pathogens to which we are exposed and, secondly, the demographic changes occurring in the community, which affect our resistance to infection. this report reviews the evidence base related to the impact of hand hygiene in reducing transmission of id in the home and community. the report focuses on developed countries, most particularly north america and europe. it also evaluates the use of alcohol-based hygiene procedures as an alternative to, or in conjunction with, handwashing. the report compiles data from intervention studies and considers it alongside risk modeling approaches (both qualitative and quantitative) based on microbiologic data. the main conclusions are as follows: (1) hand hygiene is a key component of good hygiene practice in the home and community and can produce significant benefits in terms of reducing the incidence of infection, most particularly gastrointestinal infections but also respiratory tract and skin infections. (2) decontamination of hands can be carried out either by handwashing with soap or by use of waterless hand sanitizers, which reduce contamination on hands by removal or by killing the organisms in situ. the health impact of hand hygiene within a given community can be increased by using products and procedures, either alone or in sequence, that maximize the log reduction of both bacteria and viruses on hands. (3) the impact of hand hygiene in reducing id risks could be increased by convincing people to apply hand hygiene procedures correctly (eg, wash their hands correctly) and at the correct time. (4) to optimize health benefits, promotion of hand hygiene should be accompanied by hygiene education and should also involve promotion of other aspects of hygiene. the effectiveness of hand hygiene procedures in reducing the risks of infections in home and community settings including handwashing and alcohol-based hand sanitizers there can be no doubt that advances in hygiene during the 19th and 20th centuries, along with other aspects of modern medicine, have combined to improve both the length and quality of our lives. however, since the middle of the 20th century, following the development of vaccines and antimicrobial therapy, and with serious epidemics of the ''old'' infectious enemies such as diphtheria, tuberculosis, and others apparently under control, hygiene has tended to lose its prominent position, and the focus of concern has shifted to degenerative and other chronic diseases. nowhere has the decline in concern about hygiene been more evident than in the home and community. however, whereas advances in medicine and public health seemed, at one time, to offer the possibility that infectious diseases (id) might soon be a thing of the past, it is now clear that this is not the case. in the past 20 years, concern about id and the need for prevention through home and community hygiene has moved steadily back up the health agenda. between 1980 and 1992, deaths attributable to id increased by 22% in the united states alone, representing the third leading cause of death among us residents. 1 two factors are largely responsible for this trend: first, the constantly changing nature and range of pathogens to which we are exposed and, secondly, the changes occurring in the community, which affect our resistance to infection. to what extent our more relaxed attitudes to hygiene practice have contributed to these trends is not known, but poor hygiene is a significant factor for a large proportion of the gastrointestinal (gi), skin, and respiratory tract (rt) infections, which make up the greatest part of the id burden. prior to approximately 1980, common pathogens such as rotavirus, campylobacter, legionella, escherichia coli (e coli) o157, and norovirus were largely unheard of. whereas methicillin-resistant staphylococcus aureus (mrsa) and clostridium difficile (c difficile) were once considered largely hospital-related problems, this is no longer the case. now, community-associated mrsa (ca-mrsa) strains are a major public health concern in north america and, increasingly, in europe. most recently, the severe acute respiratory syndrome (sars) outbreak and concerns about avian flu have raised awareness of the potential for transmission of respiratory viruses via hands and surfaces. demographic trends mean that the proportion of the population in the community who are more vulnerable to infection is increasing, whereas trends toward shorter hospital stays and care in the community also demand increased emphasis on care of ''at-risk'' groups in the home who require protection from infection. in assessing the potential for reducing id transmission through hygiene practice, it is recognized that contaminated hands and failure to practice hand hygiene are primary contributors. in this report, we review the evidence base related to the impact of hand hygiene in reducing transmission of id in the home and community. this report focuses on developed countries, most particularly north america and europe, within the context of renewed public health concerns about ids and their impact on health and well-being. the review also evaluates the use of alcohol-based hand hygiene procedures as an alternative to, or in conjunction with, handwashing. these products are defined by a number of different terms in europe and north america (hand sanitizers, handrubs, and others). for the purposes of this report, we will refer to them as alcohol-based hand sanitizers (abhs). although this report focuses primarily on the home, it is recognized that the home forms a continuum with public settings such as schools, offices, and public transport and cannot be considered totally in isolation. nevertheless, the hand hygiene practice framework proposed in this review is largely also applicable to ''out of home'' settings. this report compiles data from intervention studies and considers it alongside risk modeling approaches based on microbiologic data. currently, there is a tendency to demand that, in formulating evidence-based policies and guidelines, data from intervention studies should take precedence over data from other approaches. although there are those who still adhere to this, it is accepted increasingly that, as far as hygiene is concerned, because transmission of pathogens is highly complex and involves many different pathogens each with multiple routes of spread, decisions regarding infection control must be based on the totality of evidence including microbiologic and other data. this document is intended for infection control and public health professionals who are involved in developing hygiene policies and promoting hygiene practice for home and community settings, including those involved with food and water hygiene, care of domestic animals, pediatric care, care of elderly adults, and care of those in the home who may be at increased risk for acquiring or transmitting infection. the purpose of the review is to provide support for those who work at the interface between theory and practice, particularly those involved in developing policies for the home and community, by providing a practical framework for hand hygiene practice together with a comprehensive review of the evidence base. in recent years, a significant amount of research has been done to identify strategies for changing hygiene behavior. whereas those who manage hygiene improvements often choose to promote hygiene by educating people on the links between hygiene and health, one of the lessons that has been learned is that traditional (cognitive) approaches can raise awareness but do not necessarily achieve the desired effects. if practices such as handwashing are to become a universal norm, a multidimensional promotion that engages the public is needed to persuade people to change their behavior. although we recognize that this aspect is fundamental, it is outside the scope of this report and is reviewed elsewhere. [2] [3] [4] [5] [6] whereas, in the past, research and surveillance largely focused on health care-associated and foodborne illnesses, increasing resource is now being allocated to generating data that give a better view of the extent to which infections are circulating in the community; how they are being transmitted; and how this varies from one region, country, or community to another. although the data in the following section represent a useful overview, we note that the data collection methods differed significantly from one study to another, which means that comparisons from different geographic locations must be interpreted with care. current trends in communicable ids in europe are described in more detail in the recent (2007) european communicable disease epidemiological report from the european centre for disease prevention and control (ecdc). 7 infectious gi disease and hygiene foodborne disease. rates of foodborne illness remain at unacceptably high levels, despite the efforts of food producers to ensure the safety of the food supply. raw meat and poultry and fruits and vegetables bought at retail premises may be contaminated with pathogens. good hygiene practices during food preparation in the home are therefore essential in preventing cross contamination of prepared foods from raw foods and preventing contamination of food by infected household members or domestic animals. the european food standards agency (efsa) 2005 report 8 and the 2007 ecdc report 7 cite campylobacteriosis as the most reported animal infection transmitted to humans. in 2005, reported campylobacter infections increased by 7.8% compared with the previous year, rising to an incidence rate of 51.6 cases per 100,000 people. the efsa states that the source of most human campylobacter infections is related to fresh poultry meat. on the other hand, salmonella infections fell by 9.5% in 2005 to an incidence of 38.2 cases per 100,000 (176, 395 reported cases). the 2003 world health organization (who) report 9 concluded that approximately 40% of reported foodborne outbreaks in the who european region over the past decade were caused by food consumed in private homes. the report cites several factors as ''critical for a large proportion of foodborne diseases'' including use of contaminated raw food ingredients, contact between raw and cooked foods, and poor personal hygiene by food handlers. united kingdom data show that food poisoning notifications reached a peak in 1997-1998 and has since declined but remains in excess of 70,000 per year. 10 in reality, the burden of food poisoning is much higher because most cases go unreported; according to the uk food standards agency, 11 the true number of cases is approximately 4.7 million per year. in 1999, mead et al 12 reported on food-related illness in the united states, using data from a range of sources including national surveillance and community-based studies. they estimated that foodborne illness in the united states causes 76 million illnesses, 500,000 hospital admissions, and 9000 deaths each year. most frequently recorded pathogens were campylobacter, salmonella, and norovirus, which accounted for 14.2%, 9.7%, and 66.5%, respectively, of estimated foodborne illnesses. data suggest that the total number of reported outbreaks has not declined substantially in recent years, ranging from 980 to 1400 outbreaks and between 20,000 and 80,000 cases per year for the years 2000 to 2005. 13 other infectious gi disease. from recent investigations, it is now recognized that a substantial proportion of the total infectious gi disease burden in the community is because of person-to-person spread within households, particularly for viral infections, where it is most often the cause. person-to-person transmission in the home can occur by direct hand-to-mouth transfer, via food prepared in the home by an infected person, or by transmission because of aerosolized particles resulting from vomiting or fluid diarrhea. apart from transmission by inhalation of airborne particles, these infections are preventable by good hygiene practice. the 2003 who report 9 stated that, of the total gi infection outbreaks (including foodborne disease) reported in europe during 1999 and 2000, 60% and 69%, respectively, were due to person-to-person transmission. in the united kingdom, it is estimated that up to 50% of gi infection results from person-to-person tranmsission. 11 a study of united kingdom outbreaks 14 suggested that 19% of salmonella outbreaks and more than half of e coli o157 outbreaks are transmitted by nonfoodborne routes. national surveillance systems vary in their methods of data collection but mostly focus on foodborne disease. inevitably, this means that data on gi illnesses relate mainly to large foodborne outbreaks in restaurants, hospitals, and others, whereas sporadic nonfoodborne cases in the general community go largely unreported. in the united kingdom, even when ''household'' outbreaks are reported, they mostly involve home catering for parties and other functions and are therefore mainly foodborne outbreaks. 15 because milder cases of gi illness often go unreported, this means that the overall gi infection burden, particularly that which is not foodborne, is unknown; the most informative data on the overall burden of infectious gi illness (both foodborne and nonfoodborne) in the community come from various community-based studies, which have been carried out in europe and the united states and are reviewed below. two large community studies have been carried out in europe: one in the united kingdom and the other in the netherlands. the uk study, carried out from 1993 to 1996 involving 460,000 participants in the community presenting to general practice, estimated that only 1 of 136 cases of gi illness is detected by surveillance. the study indicated that as many as 1 in 5 people in the general uk population develop gi illness each year, with an estimated 9.4 million cases occurring annually of which about 50% are nonfoodborne. 11, 16 it was estimated that, for every 1 reported case of campylobacter, salmonella, rotavirus, and norovirus, another 7.6, 3.2, 35, and 1562 cases, respectively, occur in the community; based on the number of laboratory reports, it is possible to estimate the true number of infections occurring in the community (table 1) . from the community study carried out in the netherlands between 1996 and 1999, 17 it was estimated that approximately 1 in 3.5 people experience a bout of infectious gi disease each year. campylobacter was detected most frequently (10% of cases), followed by ghiardia lamblia (5%), rotavirus (5%), norovirus (5%), and salmonella (4%). relative to the population of the netherlands (16 million), 650,000 norovirus gastroenteritis cases occur annually. 18 the us study of mead et al, 12 which also included data from community-based studies, indicated that the total number of cases of infectious gi illness annually is approximately 210 million (of which approximately 64% are nonfoodborne). they estimated that the number of episodes of acute gastroenteritis per person per year is approximately 0.79. from the available data, the authors were also able to estimate the proportion of total episodes that were nonfoodborne. as shown in table 2 , by far the most frequently reported causes of gi illness were norovirus, rotavirus, and campylobacter. for campylobacter, e coli, and norovirus, a significant proportion of cases was estimated as nonfoodborne, whereas, for hepatitis a (hav), shigella, and rotavirus, almost all cases were estimated as nonfoodborne. for salmonella on the other hand, only 5% of cases were considered as nonfoodborne. davis et al reviewed outbreaks of e coli o157 related to family visits to animal exhibits. 19 indications are that norovirus is now the most significant cause of infectious gi illness in the developed world, both outbreak related and endemic. 20, 21 currently, we are seeing increased outbreaks of norovirus, a major concern in japan 22 and also in europe. 23 expert opinion is that norovirus strains now circulating are more ''virulent'' and more easily spread from person to person via hands and surfaces or during food handling. 20 infection with hav is common worldwide, 24 and adenovirus is also a frequent cause of gastroenteritis. c difficile-associated disease now occurs with increasing frequency in the community, in which it usually affects persons receiving antibiotic therapy but also healthy individuals. 25 recently, a new strain (027) of c difficile has emerged in north america, causing infections in the community among individuals with no predisposing factors. 25 a recent study 26 indicated that exposure to a family member with helicobacter pylori gastroenteritis was associated with a 4.8-fold increased risk of infection in another family member and that infection most usually involved person-to-person transmission, associated with conditions of crowding and poor hygiene. using data from the 2006 e coli o157:h7 outbreak in 2006 in the united states associated with contaminated spinach, seto et al developed a model that showed that secondary person-to-person transmission was similar to that in previous e coli outbreaks (12%). the model suggests that even a modestly effective hygiene promotion strategy to interrupt secondary transmission (prevention of only 2%-3% of secondary illnesses) could result in a reduction of 5% to 11% of symptomatic cases. 27 respiratory tract infections are largely caused by viruses. in the united states, viruses account for up to 69% of respiratory infections. 28 the common cold is reported to be the most frequent, acute infectious illness to humans. 29 data from the united states suggest that the mean number of respiratory illnesses experienced per year in adults is approximately 1.5 to 3.0, and, in children under 5 years of age, it is approximately 3.5 to 5.5. 28 approximately 80% of upper rt infections are caused by rhinoviruses. other species causing acute rhinitis are coronaviruses, parainfleunza viruses (piv), respiratory syncytial viruses (rsv), and adenoviruses. 30 although colds are generally mild and self-limiting, they represent a significant economic burden because of loss in productivity and medical costs. furthermore, secondary infections produce complications, such as otitis media, sinusitis, or lower respiratory infections including pneumonia, with its risk of mortality, particularly in elderly adults. several studies have demonstrated that colds are also a trigger for asthma. 31 rsv is the major cause of viral rt infection in young children worldwide. child day care attendance in north america caries with it a very high risk of rsv infection within the first 2 years of life and accounts for 0.5% to 1.0% of hospitalized infants in the united states. 32 influenza is a more serious rt illness, which can cause complications that lead to increased physician visits, hospitalization, and death, the risks being highest among persons aged .65 years, children aged ,2 years, and persons who have medical conditions (eg, diabetes, chronic lung disease). [33] [34] [35] influenza must also be considered in terms of days absent from work and school and pressure on health care services. 35 an important aspect of influenza is the threat associated with the emergence of novel subtypes capable of causing an influenza pandemic. 36 according to bridges et al, 37 influenza epidemics in the united states result in an annual average of 36,000 deaths and 114,000 hospitalizations; among those with influenza who belong to an ''at-risk'' group, a significant proportion develop pneumonia, and up to 1 in 10 can die of related complications. in europe, the 2004-2005 influenza season annual report 38 showed that, of 25 countries, 15 recorded what is regarded as high activity (150 up to 3000 influenza-like or acute respiratory illnesses per 100,000 population). although data indicating the role of hands and other surfaces in the transmission of colds have been available for some time, it is only in the last few years that there has been any real awareness that hands and surfaces may also be a transmission route for flu viruses. 32 evidence that measures such as hand hygiene can reduce spread of rt infections comes from the sars outbreaks in hong kong, which coincided with the latter part of influenza season, when it was observed that, as extensive personal and community public health measures took place, influenza case numbers fell significantly, more so than usual for the time of year. 39 skin and wound infections are common in the home and community, but most are self-limited. because these infections, apart from s aureus infections go unreported, little or no data are available on the burden of skin and wound infections in the community. s aureus is the most common cause of infections of skin and soft tissue, which, in a small proportion of cases, lead to the development of bacteremia or pneumonia. 40 serious infections usually occur in health care facilitiesin patients who are immunocompromised-in which s aureus is mostly usually associated with wounds and intravenous devices and in which the antibioticresistant strain, mrsa, is a major concern. infected patients discharged from hospitals and health care workers (hcws) caring for mrsa-infected patients can bring mrsa into the home and pass it on to healthy family members, who become colonized, thereby spreading the organism into the community and facilitating the circulation of these strains. [41] [42] [43] mrsa colonization in an individual can persist for up to 40 months. 44, 45 in recent years, mrsa has been increasingly found to cause infections in healthy members of the community without apparent risk factors. 25 these ca-mrsa strains are different from health care-associated (hca) mrsa strains and are a concern because they equally infect children and young adults. these strains primarily cause skin and soft tissue infections but can also cause invasive infections such as sepsis, pneumonia, and osteomyelitis, which is some cases can be fatal. 25 some ca strains are known to produce panton-valentine leukocidin (pvl), which has been implicated as a virulence factor, 46 although opinion is, however, divided as to whether this is the case; whereas some studies support this notion, 47 others do not. 48 in the united states, ca-mrsa is now a significant concern. ca-mrsa strains have also now been detected in france, switzerland, germany, greece, the nordic countries, australasia, the netherlands, and latvia. 25 in the united kingdom, cases of ca-mrsa and pvlproducing strains have been reported, but the number of reported cases is still small. 25, 49 within the global population that affect our resistance to infection.''at-risk'' groups cared for at home include not only newborn infants whose immune system is not fully developed but also the rapidly increasing elderly population whose immune system is declining. ''atrisk'' groups include patients discharged recently from hospital, immunocompromised family members, and family members with invasive devices such as catheters. it also includes people whose immunocompetence is impaired as a result of chronic and degenerative illness or because they are undertaking certain drug therapies. all of these groups, together with those who carry hiv/aids, are increasingly cared for at home by a caregiver, who may be a household member. a survey of the united states and 3 european countries-germany, the netherlands, and the united kingdom-suggests that up to 1 in 5 of the population belongs to an ''at-risk'' group (table 3) . the data suggest that between 12% and 18% of the population of these countries are .65 years of age. in an intervention study of 148 patients with aids, it was found that patients assigned to the intensive handwashing intervention group developed fewer episodes of diarrheal illness (1.24 6 0.9 vs. 2.92 6 0.6 new episodes of diarrhea, respectively, during a 1-year observation period. 50 gi pathogens are now implicated as causative or contributory factors in the development of cancers and other chronic conditions; examples include hepatitis b virus (hepatocelluar carcinoma), 51 h pylori (peptic ulcer disease), 52 and campylobacter jejuni (guillain barrã© syndrome). 53 foodborne illness has been estimated to result in chronic sequelae in 2% to 3% of cases 54 ; a european commission report 55 cites evidence of chronic disease, such as reactive arthritis, following 5% of salmonella cases, with 5% of e coli o157 cases progressing to serious and even fatal complications. even mild viral infections can be predisposing factors to more severe and possibly fatal secondary bacterial infections. 56 in devising a strategy for home hygiene and producing hygiene practice advice, the international scientific forum on home hygiene (ifh) has developed an approach based on risk management that involves identifying the ''critical control points'' for preventing the spread of id in the home. risk management (also known as hazard analysis critical control points [haccp] ) is now the standard approach for controlling microbial risks in food and other manufacturing environments and is becoming accepted as the optimum means to prevent such risks in home and hospital settings. 57 the key feature of the ifh approach is that it recognizes the need to look at hygiene from the point of view of the family and the total range of problems it faces to reduce id risks, including food hygiene, personal hygiene (particularly hands) and hygiene related to the general environment (toilets, baths, hand basins, surfaces, and others), domestic animals, and family members at increased risk. adopting a holistic approach makes sense because all these issues are interdependent and based on the same underlying microbiologic principles. haccp also forms the basis for developing an approach to home hygiene that can be adapted to meet differing needs. indeed, it is only by adopting such a holistic approach that the causal link between hands and infection transmission in the home can be addressed properly because hand hygiene is a central component of all these issues. the ifh risk management approach to hygiene starts from the principle that pathogens are introduced continually into the home by people (who may have infection or may be asymptomatic), food, and domestic animals and also sometimes via the water or the air. additionally, sites at which stagnant water accumulates, such as sinks, toilets, waste pipes, or items, such as cleaning or face cloths, readily support microbial growth and can become a primary reservoir of infection; although microbial species are mostly those that represent a risk to vulnerable groups, primary pathogens can also be present. 58 so long as there are people, pets, and food in the home, there will always be the risk of pathogenic microbes. in many homes, there will also be at least one family member who is more susceptible to infection for one reason or another. within the home, there is a chain of events, as described in fig 1, that results in transmission of infection from its original source to a new recipient. to an extent, we can limit the exit and entry of pathogens from and into the body, but the link that we have most control over is that related to the ''spread of pathogens.'' the spread of infection can be interrupted by good hygiene practice, which includes adherence to hand hygiene recommendations and cleaning and disinfecting contaminated environmental surfaces. the risk-based approach to home hygiene is described in more detail by bloomfield and scott 59 and bloomfield. 60 they suggest that sites and surfaces in the home should be categorized into 4 main groups: reservoir sites, reservoir/disseminators, hands and hand and food contact surfaces, and other surfaces. risk assessment is then based on the frequency of occurrence of pathogenic contamination at that site, together with the probability of transfer from that site such that family members may be exposed. this means that, even if a particular environmental site is highly contaminated, unless there is a high probability of transfer from that site, the risk of infection transmission is low. from this, it is possible to determine the ''critical control points'' for preventing spread of infection. the data suggest the following: d for reservoir sites such as the sink waste pipes or toilets, although the probability of contamination (potentially pathogenic bacteria or viruses) is high, the risk of transfer is limited unless there is a particular risk situation (eg, a family member with enteric infection and fluid diarrhea, when toilet flushing can produce splashing or aerosol formation that can settle on contact surfaces around the toilet). 58,61 d by contrast, for reservoir sites such as wet cleaning cloths, not only is there high probability of significant contamination, but, by the very nature of their usage, they carry a high risk of disseminating contamination to other surfaces and to the hands. d for hands and hand contact and food preparation surfaces, although the probability of contamination is, in relative terms, lower, it is still significant, for example, particularly following contact with contaminated food; people; pets; or other contaminated surfaces such as door, faucet, and toilet-flush handles. because there is a constant risk of spread from these surfaces, hygiene measures are important for these surfaces. d for other surfaces (floors, walls, furniture, and others), risks are mainly due to pathogens such as s aureus and c difficile, which survive under dry conditions. because the risks of transfer and exposure are relatively low, these surfaces are considered low risk, but where there is known contamination, for example, soiling of floors by pets, crawling infants may be at risk. cleaning can also recirculate dust-borne pathogens onto hand and food contact surfaces. overall, this approach allows us to rank these various sites and surfaces (fig 2) according to the level of transmission risk; this suggests that the ''critical control points'' for breaking the chain of infection are the hands, together with hand and food contact surfaces, cleaning cloths, and other cleaning utensils. however, although this is a useful ''rule of thumb'' ranking, it is not a constant. for example, although risks from toilets, sinks, floors, and others relate mainly to the relatively lower risk of transfer from these sites to hands, hand and food contact surfaces, and cloths, this risk can increase substantially during occasions when an infected family member has fluid diarrhea or when a floor surface is contaminated with vomitus, urine, or feces. in the following section, we evaluate data indicating the extent to which the hands, both alone and in combination with other surfaces, are responsible for the spread of infection. the criteria for assessing causal inference of a link between hygiene practice and id risk reduction have been reviewed by aiello and larson. 62 establishing the potential health impact of a hygiene intervention such as hand hygiene requires examination of the evidence related to a range of criteria that should include the strength, consistency, and temporality (cause and effect) of the association, together with data on plausibility (biologic or behavioral rationale) and biologic gradient. aiello and larson recognize that, although a single factor such as the hands may be a ''sufficient cause'' of infection transmission, spread of infection frequently involves a number of ''component causes,'' which, together or independently, work to determine the overall risk. the risk assessment approach, as outlined above, indicates that the ''critical control points'' or ''component causes'' of infection transmission in the home are the hands, together with hand and food contact surfaces and cleaning cloths. based on plausibility, the role of the hands relative to other surfaces can be understood by mapping the potential routes of spread of gi, rt, and skin infections in the home as shown in fig 3. this suggests that, for all 3 groups of infections, the hands are probably the single most important transmission route because in all cases they come into direct contact with the known portal of entry for pathogens (the mouth, nose and, conjunctiva of the eyes) and are thus the key last line of defense. figure 3 shows, however, that, although in some cases the hands alone may be ''sufficient cause'' for transmission of an infection (eg, from an mrsa carrier, to hands, to the wound of a recipient), in other cases transmission involves a number of component causes (eg, from contaminated food, to a food contact surface, to hands, to the mouth of a recipient). what this means is that the transmission risk via the hands also depends on the extent to which surfaces become contaminated with pathogens during normal daily activities, ie, the risk of hand-to-mouth transfer will be increased if extensive transfer from raw food to food preparation surfaces also occurs. defining the importance of hand hygiene relative to other hygiene practices, such as surface and cloth hygiene, is difficult because of the close interdependence of these factors. although the focus of this review is the prevention of infection through hygiene practice, fig 3 shows that in some cases airborne transmission can operate independently, without involving the hands, whereas, for gi infection, transmission can operate independently via food. although handwashing intervention studies provide data supporting the causal link between hand contamination and id transmission, defining the importance of hand hygiene relative to other hygiene practices, such as surface and cleaning cloth hygiene, or the risks associated with airborne transmission is difficult because of the close interdependence of these factors. currently, such assessments can only be made on a qualitative basis, using microbiologic data (as in the following section) together with some limited epidemiologic data. in this section, we present epidemiologic and microbiologic data to support the causal relationship between hygiene and id risk. because the risks of hand transfer increase as the risks of contamination of other surfaces increases, data related to relevant surfaces are also included. in recent years, a range of studies has been published, many related specifically to the home, which indicate the extent to which id agents occur and are spread in home and community settings during normal daily activities and their potential to cause infection. these studies include assessments of frequency occurrence of sources of pathogens in the home, their rate of ''shed'' from an infected source into the environment, their rate of die away on hands and other surfaces, their rate of transfer via the hands to the mouth, nose, conjunctiva, and others and/or to ready-to-eat foods, and their the infectious dose. the infectious dose (ie, the number of particles to which the recipient is exposed), their immune status, and the route by which they are infected are key factors that determine the infection risk. the ''infectious dose'' varies for different pathogens and is usually lower for people who are ''at-risk'' than for healthy household members. transmission of infectious gi disease. risks from exposure to gi pathogens via the hands. as shown in fig 3 , exposure to gi pathogens can occur by direct hand-to-mouth contact or indirectly via contaminated food. in the home, food can be contaminated either directly by an infected food handler or indirectly by cross contamination via hands and surfaces from another source, which may be contaminated food, another infected household member (or carrier), or a household pet or farm animal. hand-to-mouth contact is a frequent occurrence, particularly among children; a study of mouthing behavior in 72 young children showed that children ,24 months of age exhibit the highest frequency, with 81 events/hour; for children .24 months of age, this was reduced but was still of the order of 42 events/hour. 63 the potential for transmission of pathogens from hands to ready-to-eat foods is supported by a number of studies: d in a model domestic kitchen, 29% of food preparation sessions using campylobacter-contaminated chicken resulted in positive campylobacter isolations from prepared salads, cleaning materials, and food contact surfaces. 64 d bidawid et al 65, 66 showed that touching lettuce with finger pads contaminated with hav and feline calicivirus (fcv), used as a surrogate for norovirus, for 10 seconds resulted in transfer of 9.2% and 18%, respectively, of the virus. based on the load for hav in feces (10 6 to 10 9 viral particles/g), an estimated 1300 particles were transferred to the lettuce. d rusin et al showed that, when volunteers' fingertips were inoculated with a pooled suspension of micrococcus luteus (m luteus), serratia rubidea (s rubidea), and bacteriophage prd-1 and held to the lip area, transfer rates were 40.99%, 33.97%, and 33.90%, respectively. 67 as stated above, the infection risk from oral consumption depends on the number of bacterial cells or viral particles that are consumed. table 4 shows that, for many of the commonly occurring gi pathogens, the infectious dose is relatively small. sources and spread of gi pathogens to the hands. figure 3 illustrates that the risk of exposure to gi pathogens via the hands depends on the extent to which these pathogens are brought into the home (either by infected people or pets or via contaminated food) and the extent to which they are spread via hands and other surfaces and by airborne transmission. relevant data from various sources, as summarized below, suggest that exposure to gi pathogens via the hands is a frequent occurrence during normal daily activities and that the numbers of organisms transferred by handto-mouth contact can be well within the numbers required to cause infection. household members who are infected, or who are carriers, are a primary source of infection in the home. pathogens that can be carried persistently by otherwise healthy people include salmonella species and c difficile. approximately 3% of adults (mainly those .65 years of age), and up to two thirds of babies, are known to carry c difficile in their gut, although it is not known what proportion are toxin producing. 25 people or animals that carry gi pathogens shed large numbers of organisms in their feces or when they vomit. a single vomiting incident following norovirus infection may produce 30 million viral particles, 72 and, at the peak of a rotavirus infection, .10 11 virions may be excreted per gram feces. 74 surfaces in the home may become contaminated by enteric organisms that are aerosolized during vomiting or by transfer of vomitus and fecal matter via hands. viruses aerosolized from flushing the toilet can remain airborne long enough to contaminate surfaces throughout the bathroom. 75 infectious agents introduced into the home via food include salmonella, campylobacter, listeria, and e coli o157. a variety of foods can act as a source of these organisms, including meat, fish and poultry products, dairy products, fruits, and vegetables. organisms in particles, and moisture or juices, from food will contaminate any surface they come into contact with. an salmonella species up to 10 6 but could be as low as 10-100 cells. 68 contamination may be amplified by transfer to foods, which are then stored incorrectly. campylobacter species 500 organisms can result in human illness. 69 oral dose for e coli 0157 may be as little as 10 cells. 70 in one outbreak, a median dose of ,100 organisms per hamburger was reported. 71 norovirus 10-100 units or even less. 72 may be as few as 10 particles. 73 ward et al showed that 13 of 14 adults became infected after consuming rotavirus (10 3 particles) picked up from a contaminated surface via the hands. 73 efsa survey 76 of salmonella in chicken indicates significant differences among eu member states, with isolation rates between 0% and 68.2%; the level reported for the united kingdom was 7.1% to 9.4%. the efsa also reported that up to 66% of samples from fresh poultry were positive for campylobacter. 77 in the united states, more than half of raw chicken is estimated to be contaminated with camplylobacter. 76 chapman et al 78 showed that 0.4% to 0.8% of meat products purchased from uk butchers were positive for e coli o157. in a recent study in canada, c difficile was isolated from 20% of 60 samples of retail ground meat purchased over a 10-month period, and 11 isolates were toxigenic. 79 the home is frequently a shelter to a range of different pets; more than 50% of homes in the englishspeaking world have cats and dogs, with 60 million cats and dogs in the united states. in the united states, up to 39% of dogs may carry campylobacter, and 10% to 27% may carry salmonella 80 ; cats are also carriers of these organisms. carriage of c difficile in household pets is quite common; up to 23% of pets are affected, although these mostly involve noncytotoxigenic strains. 25 kramer et al, 81 sattar et al, 82 and rzezutka and cook 83 reviewed data showing that gi pathogens can survive on surfaces for several hours and, in some cases, days, particularly on moist surfaces, although infectivity depends on the numbers that survive (table 5) . studies to quantify transfer between hands, foods, and kitchen surfaces 67, 84 showed that transfer rates were highly variable, ranging from as high as 100% to as low as 1%. transfer to hands was highest from nonporous surfaces but lower from surfaces such as carrots, sponges, and dishcloths (,1%). rusin et al 67 sampled volunteers hands after touching surfaces contaminated with m luteus, s rubidea, and phage prd-1. activities included wringing out a dishcloth/sponge, turning off a faucet, cutting up a carrot, making hamburger patties, holding a phone receiver, and removing laundry from the washing machine. transfer efficiencies for the phone receiver and faucet were 38% to 65% and 27% to 40%, respectively. paulson 85 showed that, when gloved hands were contacted for 5 to 10 seconds with surfaces such as cutting boards and doorknobs contaminated with fcv (log 5.9 particles), the log number of particles recovered from hands was 4.7 to 5.4. these laboratory studies are supported by a range of field studies showing spread via the hands and other surfaces during normal daily activities: d following preparation of salmonella and campylobacter-contaminated chickens in domestic kitchens, these species were isolated from 17.3% of hands and hand and food contact surfaces. isolation rates were highest for hands, chopping boards, and cleaning cloths (25%, 35%, and 60%, respectively, of surfaces sampled). 86 d in homes containing an infant recently vaccinated for polio (during which time shedding occurs in feces), virus was isolated from 13% of bathroom, living room, and kitchen surfaces. 87 most frequently contaminated were hand contact sites such as bathroom taps, door handles, toilet flushes, soap dispensers, nappy changing equipment, and potties. d following handshaking with a volunteer whose hands were contaminated from touching a viruscontaminated door handle, successive transmission from one person to another could be followed up to the sixth person. 88 d where fingers were contacted with noroviruscontaminated fecal material, the virus was consistently transferred via the fingers to melamine surfaces and from there to hand contact surfaces, such as taps, door handles, and telephone receivers. contaminated fingers sequentially transferred the virus to up to 7 clean surfaces. 89 d a study 90 with fcv showed survival for up to 3 days on telephone buttons and receivers, for 1 or 2 days on computer mouse, and for 8 to 12 hours on keyboard keys and brass disks representing faucets and door handles. the time for 90% virus reduction was ,4 hours on computer keys, mouse, and brass disks; 4 to 8 hours on telephone receivers; and 12 to 24 hours on telephone buttons. d in homes of infants with recurrent c difficile infection, 12% of environmental surfaces were positive for c difficile, and 1 of 4 other household members carried c difficile in stool. in a control home with no household carriers, none of 84 environment samples were positive for c difficile. 91 d in 4 out of 6 homes in which there was a salmonella case, the causative species was isolated from fecal soiling under the flushing rim and scale material in the toilet bowl for up to 3 weeks after notification of infection. 58 flushing toilets seeded with salmonella enteritidis resulted in contamination of hand contact surfaces such as toilet seats and toilet seat lids. these represent recent examples of studies that have been reported. these and other studies are also reviewed elsewhere. 82, [92] [93] [94] in developing hygiene policies for preventing gi infections, one of the difficulties is assessing risks associated with hand transmission relative to other risks such as inadequate cooking or storage of food or inhalation of infected vomit particles. gillespie et al 15 reported an evaluation of reported outbreaks linked to uk households for 1992 to 1999 that suggested, of the 85% of outbreaks designated as foodborne, cross contamination was implicated in 20% of outbreaks compared with 30% and 31% of outbreaks for which inadequate storage and cooking, respectively, were thought to be the cause. there were no data to suggest what percentage of cross contamination events involved the hands, and gillespie et al 15 expressed concern that most of the reported outbreaks were linked to home catering, thus not necessarily representative of normal daily routine. aerosol transmission can result from settling on hand and food contact surfaces, but, for norovirus, infection can sometimes result from direct inhalation of infected particles of vomit by people immediately adjacent to the person who vomits. the potential for airborne transmission of norovirus was demonstrated in studies in a restaurant and a primary school, in which close proximity to infected persons in the immediate aftermath of a vomiting attack was identified as a risk factor. 95, 96 transmission of rt infections. the last 2 years have seen an unprecedented global focus on developing strategies for preventing transmission of influenza. the who 97 is taking a lead on pharmaceutical interventions such as vaccines and antivirals but has also made recommendations for other interventions, 98 which include highlighting the importance of hygiene, and in particular hand hygiene, in minimizing spread in the home and community. risks from exposure to respiratory pathogens via the hands. as shown in fig 3, exposure to rt viruses can occur either by inhalation of infected mucous or inoculation of the nasal mucosa or eyes with viruscontaminated hands, which then cause infection via the mucous membranes and upper rt. rhinovirus and rsv are deposited into the front of the nose or into the eye (where they pass down the lacrymal duct), either on the end of the finger or possibly sometimes in aerosolized droplets. 99 rubbing the eyes and nose with the fingertips is a common occurrence; hendley et al found that 1 in 2.7 attendees of hospital rounds rubbed their eyes, and 33% picked their nose, within a 1-hour observation period. 100 a review of the data 94 (table 6 ) suggests that the infectious dose for respiratory viruses is relatively small. alford et al suggest that aerosolized doses of as little as 1 tcid 50 (tissue culture infective dose) of influenza virus could infect volunteers. 101 evidence for transmission of rhinovirus and rsv infections via contaminated hands comes from a number of studies: d a number of studies have demonstrated that selfinoculation by rubbing the nasal mucosa or conjunctivae with rhinovirus-contaminated fingers can lead to infection. 100, 102 over a period of 10 years, gwaltny and hayden performed intranasal challenges on 343 healthy young adults who had no antibody to the challenge, and infected 321 (95%). 103 after handling contaminated coffee cups and other objects, more than 50% of subjects developed infection. 104 hall et al showed that volunteers touching contaminated objects and/or the fingers of symptomatic individuals had a higher attack rate of colds if they touched their eyes or nose. 105 d in a 4-year family trial, hendley and gwaltney 104 found that prophylactic treatment of mothers' fingers with iodine reduced the incidence of rt infections. when illness occurred in the family, mothers were instructed to dip their fingers in iodine upon awakening in the morning, then every 3 or 4 hours or after activities that washed the iodine from the skin. the secondary attack rate in mothers was 7% in the iodine group and 20% in placebo families. no infections occurred in mothers after 11 exposures to an infected index case in the iodine group, compared with 5 infections after 16 exposures in the placebo group. d hall et al showed that infected infants excrete prodigious amounts of rsv in their nasal secretions for several days 105 and that rsv could be recovered from hands that had touched surfaces contaminated with secretions from infected infants. 99 hall and douglas found that close contact with symptomatic infants who were producing abundant secretions, or their immediate environment, was necessary for infection. 106 sources and spread of rt pathogens to the hands. figure 3 illustrates that the risk of exposure to rt pathogens via hands depends on the extent to which these pathogens are spread from an infected person during normal daily activities. relevant data come from various sources and are summarized below. taken together, the data suggest that, when a household member is infected, exposure of other household members via hands is likely to occur during normal daily activities and that the numbers of organisms involved are within those required to initiate infection if transferred to the eyes or nose. people infected with cold viruses shed large quantities of virus-laden mucus. droplets of nasal secretions generated by coughing, sneezing and talking can travel over a distance .3 m to contaminate surrounding surfaces. 37, 98, [107] [108] [109] up to 10 7 infectious influenza particles per milliliter has been detected in nasal secretions. 110 the mean duration of a cold is 7.5 days. viral shedding may occur 24 to 48 hours before illness onset but generally at lower titers than during the symptomatic period. titers generally peak during the first 24 to 72 hours of illness and decline within several days, with titers low or undetectable by day 5. children can shed virus for up to 3 weeks, whereas immunocompromised people may continue to shed virus for weeks to months. 98 infectious material can also be deposited directly on hands and tissues during sneezing and blowing the nose. contamination of hands can occur by handshaking or touching contaminated surfaces. pathogens shed into the environment from these sources can survive for significant periods and are readily spread around the home to and from the hands and via handkerchiefs and tissues, tap and door handles, telephones, or other hand contact surfaces: d gwaltney and hendley demonstrated that most subjects with experimental colds had rhinovirus on their hands and that virus could be recovered from 43% of plastic tiles they touched. 104 for people with rhinovirus colds, virus was found on 39% of hands and 6% of objects in their immediate environment. 100 opinion as to the importance of the hands relative to the airborne route for transmission of rhinovirus colds is divided. some investigators 30, 99, 103, 104 maintain that contamination of the hands followed by inoculation of the eyes or nose is of paramount importance; in fact, gwaltney et al found that it was exceedingly difficult to transmit virus orally or by kissing and found little evidence of droplet or droplet nuclei transmission. 100, 113 others maintain that the evidence favors droplet and droplet nuclei transmission as the most important mode of spread. 118 for rsv, there is general agreement that the hands are the primary route for the spread of infection. 32, 105, 106 for influenza, although more data are needed, it is increasingly accepted that not only airborne (both true airborne transmission involving droplet nuclei [,5 mm in diameter] and ''droplet transmission'' involving droplets .10 mm that deposit onto surfaces quite rapidly) but also surface (including hand) transmission come into play. 98, 119, 120 the relative contribution of each mode of transmission is unknown but appears to vary depending on the circumstances, symptoms, respiratory tract loads, and the viral strain. 121 data from animal studies and influenza outbreaks suggest that droplets generated when infected persons cough or sneeze are the predominant mechanism of airborne transmission, 37 although data supporting droplet nuclei spread are also available. 101, [122] [123] [124] it is possible, however, that influenza is less transmissible via hands and surfaces compared with rhinovirus and others because of its lower ability to survive outside a human or animal host. data suggest that, to some extent, airborne droplets and droplet nuclei cause infection as a result of settling on hand contact surfaces. the frequent occurrence of diarrhea and the detection of viral rna in fecal samples tested suggest that the h5n1 influenza virus may replicate in the human gut and could be a source of transmission via hands and surfaces. 125 at present, however, it is thought that this is unlikely. the growing evidence base related to the survival, transmission, and human exposure to rt viruses via hands and other surfaces is also reviewed elsewhere. 32, 35, 37, 82, 94, 99 transmission of skin and wound infections. risks from exposure to skin and wound pathogens via the hands. as shown in fig 3, exposure to skin pathogens such as s aureus can occur via the hands. exposure can produce colonization and/or infection that usually occurs in areas in which there are cuts, abrasions, and others that damage the integrity of the skin. where there are predisposing factors, the numbers of organisms required to produce infection may be relatively small. marples 126 showed that up to 10 6 cells may be required to produce pus in healthy skin, but as little as 10 2 may be sufficient in areas in which the skin is occluded or traumatized. risks associated with exposure to hca-mrsa and ca-mrsa are different. hca-mrsa usually affects elderly adults and those who are immunocompromised, particularly those with surgical or other wounds or who have indwelling catheters. for ca-mrsa, those at particular risk appear to be younger, generally healthy people who practice contact sports or other activities that put them at higher risk of acquiring skin cuts and abrasions. 127 us experience suggests that ca-mrsa may be more virulent than other strains and is easily transmissible within households and community settings (eg, schools, day care centers, sport teams) in which skin-to-skin contact or sharing of contaminated items (eg, towels, sheets and sport equipment) are vehicles for person-to-person transmission. 128 a case-control study 129 involving 55 cases of mrsa in a us prison showed that inmates who washed their hands #6 times per day had an increased risk for mrsa infection compared with inmates who washed their hands .12 times per day. sources and spread of skin and wound pathogens to the hands. figure 3 illustrates that the risk of exposure to skin pathogens via the hands depends on the extent to which people or animals colonized or infected with pathogenic strains are present in the home and the extent to which these pathogens are spread during normal daily activities. transfer of skin pathogens to the hands can occur either by direct contact with an infected source or indirectly via hand contact surfaces or the surfaces of clothing or household linens. relevant data, as outlined below, suggest that, when there is a person in the home who is infected or colonized with s aureus, exposure of other household members as a result of transfer via hands, surfaces, clothing, and others is likely to occur during normal daily activities and that the numbers of organisms involved are within the numbers of particles that could initiate an infection in a susceptible recipient. a study by kluytmans et al suggests that s. aureus is carried as part of the normal body flora in up to 60% of the general population, 130 although a 2006 us study 131 suggests that the carriage rate is much less (31.6%). in the united kingdom, indications are that the proportion of the general population carrying antibiotic-resistant strains of s aureus (either hca-or ca-mrsa) is somewhere between 0.5% and 1.5%, the majority being carriers of hca-mrsa who are .65 years of age and/or have had recent association with a health care setting. 132 although cases of ca-mrsa and pvlproducing mrsa have been reported, indications are that the prevalence of mrsa and pvl-producing strains circulating in the community is currently very small. 25 in the united states, although it is concluded that colonization rates for mrsa in the community are still low, it is nonetheless thought to be increasing. 127, 133 graham et al 131 report on an analysis of 2001-2002 data from the national health and nutrition examination survey (nhanes) to determine colonization with s aureus in a noninstitutionalized us population. from a total of 9622 participants, it was found that 31.6% were colonized with s aureus, of which 2.5% were colonized with mrsa. of persons with mrsa, half were identified as strains containing the sccmec type iv gene (most usually associated with ca-mrsa), whereas the other half were identified as strains containing the sccmec type ii gene (most usually associated with hca-mrsa). several other investigators have examined the epidemiology of mrsa in the us community; differences in the data suggest a sporadic distribution of ca-mrsa, with carriage rates ranging from 8% to 20% in baltimore, atlanta, and minnesota 127 up to 28% to 35% for an apparently healthy population in new york. 134 domestic pets can also be a source of s aureus, including mrsa and pvl-producing strains. [135] [136] [137] [138] [139] manian 136 described 2 dog owners suffering from persistent mrsa infection, who suffered relapses whenever they returned home from the hospital; further investigation revealed that the dog was carrying the same strain of mrsa. people who carry s aureus can shed the organism in large numbers most usually associated with skin scales. 140 kramer et al 81 review data showing that s aureus (including mrsa) can survive on dry surfaces for periods from 7 days up to 7 months. scott and bloomfield showed that, during a 4-hour drying period, up to 50% of s aureus inoculated onto laminate could be transferred to fingertips by contact. transfer to fingertips also occurred when a cloth contaminated with s aureus was used to wipe a clean surface. 141 studies in health care settings, as reviewed by bloomfield et al, 25 147 found that transmission of the mrsa strain from an index case to 2 siblings and the mother occurred at least 3 times, and one family member was colonized for up to 7 months or more. these represent recent examples of studies that show survival and transfer of mrsa around the home. these and other studies are also reviewed by bloomfield et al. 25 intervention studies to establish the causal link between hand hygiene and infectious disease in the home and community both observational and interventional study designs have been used to assess the relationship between hand hygiene and id transmission. by definition, observational studies are not randomized and must utilize careful methods to preserve internal validity. control of confounding and the potential for selection, recall, and other biases are also a concern, for example, individuals who wash their hands less frequently are also less likely to report symptoms. intervention studies on the other hand compare infection rates in groups in which handwashing is, or is not, promoted. intervention studies employing randomization of treatment groups have been considered the ''gold-standard'' in terms of reducing selection biases. these studies have the ability to ensure that randomized groups are similar, apart from treatment allocation and differences that occur by chance. for these reasons, we limit discussion to intervention studies, focusing on gi and rt illnesses, because these are the most common infectious illness symptoms in home and community settings. a range of intervention studies have been carried out to evaluate the causal link between handwashing and id transmission and have been reviewed in a series of papers to assess the consistency and strength of the link. [151] [152] [153] overall, these studies indicate a strong and consistent link between handwashing and gi disease and a significant link between handwashing and rt illnesses. for the most part, these studies have been carried out in child day care centers, schools, and military and other public settings in which the outcome is often measured against a high baseline level of infection. relatively few studies have been carried out in household settings in the united states and europe. difficulties associated with studying households in developed areas include fewer children under the age of 5 years, higher level of hygiene infrastructure, and difficulties in collecting data. given that there are likely fewer susceptible individuals clustered within household settings, the prevalence of gi and rt illnesses is relatively much lower, making it more difficult to detect a significant influence of hand hygiene on the occurrence of illness. whereas some intervention studies are not relevant to this review and have been omitted, others give useful insight into the potential impact of handwashing in the home and in the general community. studies that are included have been selected on the basis of whether transmission routes are likely to reflect those in the home, most particularly whether the relative rates of transmission via these routes (as shown in fig 2) are likely to be similar. for this reason, studies on gi infection in developing countries have been excluded; in these settings, limited access to sanitation means that rates of direct hand-to-mouth transmission from feces is high relative to other routes of transmission (eg, person-to-person transmission via hands, or inadequate food hygiene), compared to settings with adequate water and sanitation in which transmission is more likely to involve person-to-person transmission and transmission via food, rather than direct feces-to-hand-to-mouth. for gi illnesses, we have, therefore, focused on studies carried out in developed country communities, although, even for studies such as those in child daycare centers, in which food preparation is not undertaken by study participants, the data probably reflect mainly the impact on person-to-person transmission. for rt infections, studies conducted in both developed and developing countries are included on the basis that relative rates of airborne transmission versus transmission via hands are likely to be similar regardless of setting. in a recent review, aiello et al assessed the relationship between handwashing and gi outcomes 154 focusing on studies conducted in north america and europe. table 7 summarizes studies providing an effect estimate (risk ratio, rate ratio, and others) as well as 95% confidence intervals (95% ci). in all of the studies, handwashing with soap was the factor studied, although in some, this was combined with hygiene education measures. all studies assessing handwashing and hand hygiene education were conducted in school or day care settings. among the studies in table 7 , the reduction in gi illness associated with handwashing ranged from 210% to 157%. however, 3 of the 5 studies were not statistically significant, including the study that identified a value of 210%. the studies that gave statistically significant results all describe reductions close to 50%. overall, these reviews suggest a consistent causal relationship between handwashing and reduction in gi illness, although the findings are less consistent and of a lesser magnitude than in lesser developed settings in which studies considered statistically significant suggested reductions from 26% to 79%. 154 in assessing rt infections, the reviews of aiello and larson 151 and aiello et al, 154 mentioned above, 161 they reported that hand hygiene (handwashing, education, and waterless hand sanitizers) can reduce the risk of respiratory infection by 16% (95% ci: 11%-21%). these investigators have now updated their estimate with 2 further, more recent, studies that, when all studies are taken together, give a pooled impact on respiratory infection of 23%. 162 based on these studies, table 8 summarizes the results of community-based interventions (excluding health care-related and military settings) on rt illnesses. most studies were conducted in economically developed countries (83%, 5/6). the range of reduction in illness was 5% to 53%, but only 33% (2/6) of the studies were statistically significant. the results suggest that hand hygiene education and promotion of handwashing can reduce rates of rt illnesses, but the impact is less than for gi infections, although it must be borne in mind that the available data are more limited. 154 there are also several studies of handwashing that do not distinguish between gi and rt outcomes. 157, 167, 168 these studies measure outcomes such as illness-related absenteeism, making it difficult to assess the impact on specific disease etiologies. of these studies, only one reported a significant reduction (25%). 157 two were conducted in day care centers, and 1 was conducted in an elementary school. all 3 studies were conducted in economically developed areas (united states, sweden, and israel). 157, 167, 168 several methodologic issues must be considered for these studies. studies that use randomization are more likely to produce study groups with similar baseline characteristics. surprisingly, 40% of the 11 studies in tables 7 and 8 did not randomize. in some studies, randomization may not be an option (eg, in community settings) because the intervention is too complicated to randomize to multiple groups rather than assigning it to a single geographic area. controlling for potential confounding variables is also an important issue, for example, if a study did not control for age and included adults as well as children, the effect of a hygiene intervention may be diluted because adults are at lower risk for diarrheal disease compared with children. in randomized studies, adjustment for confounding in the statistical analysis may not be required if potential confounders associated with intervention and control groups appear balanced, for example, randomization of households in the same geographic area may produce intervention and control arms with the same age distributions, hygiene habits, and health profiles. as summarized in table 9 , of the 11 studies, only 50% (9/18) reported controlling for at least 1 potential confounding factor. although masking (also known as blinding) can be difficult to implement in hygiene studies because subjects, observers, and interviewers are usually aware of the intervention status, a few studies (2/18) were able to employ masking to reduce knowledge of the intervention. masking can reduce biases associated with knowledge of intervention, including changes in behaviors, practices, and data collection methods. for intervention studies, disregarding clustered sample design may cause bias. for example, a handwashing program in a day care center may affect a child's risk of disease through its individual-level effect (the effect of handwashing of a child on his or her own risk of disease) and through its group-level effect (the effect of centerwide handwashing on risk of disease, even if the child is not following the handwashing program). clustered interventions must take into account the grouped data structure in subsequent analyses or must analyze data at the in the section above, which describes the development of a risk-based approach to home hygiene, we evaluated how pathogens are introduced into the home and the chain of events that can lead to healthy household members becoming infected. an assessment of the microbiologic data related to each stage of the infection transmission cycle suggests that the critical control points for preventing the spread of infection in the home are the hands, hand contact surfaces, food contact surfaces, and cleaning cloths and utensils. intervention at the appropriate time (eg, during raw food handling, rather than as part of daily routine cleaning) is an equally fundamental part of a riskbased approach to hygiene. in practice, pathogens may be transmitted by more than one route, and it is impossible to achieve 100% hand hygiene compliance. therefore, interventions to reduce id transmission in the home must be multifaceted. key to preventing infection transmission via the hands (and other surfaces) is the application of effective hygiene procedures. because the evidence reviewed in the earlier sections shows that the ''infectious dose'' for many common pathogens such as campylobacter, norovirus, and rhinovirus can be very small (1-500 particles or cells), intuitively one must argue that, in situations in which there is significant risk, the aim should be to get rid of as many organisms as possible from critical surfaces. organisms can be removed from hands and other surfaces by the following: d physical removal using soap or detergent-based cleaning; or d microbes can be killed in situ by applying a disinfectant or sanitizer. in principle, handwashing using soap or detergent and water mechanically dislodge organisms, but, to be effective, it must be applied in conjunction with a rubbing process that maximizes release of microbes from the skin and a rinsing process that washes the organisms off the hands. although elimination of transient contamination from the hands by the application of a hygiene procedure is plausible, the evidence considered below suggests that, in practice, procedures vary considerably in the extent to which they achieve this. in this section, data on the efficacy of hand hygiene procedures are summarized. a range of test methods has been used to measure the efficacy of hand hygiene products and procedures. although these methodologies yield valuable data, the results can vary considerably depending on the method used. in 2004, sickbert-bennet et al 169 produced a study, based on published literature and their own data, which indicated that factors that affect efficacy measurements are as follows: use of experimental contamination versus normal flora, application method of test organism, type of hand hygiene agent, concentration of active ingredient, volume, duration of contact and application method of the agent, and study method (in vivo panel test vs in vitro suspension test). interpretation of data is made difficult by failure to compare multiple agents in the same study; because of these limitations, comparisons of results from different studies must be interpreted with care. in vivo ''panel test'' studies of the effectiveness of handwashing. in europe, the efficacy of handwashing is established by panel tests that determine the reduction in the number of organisms released from artificially contaminated hands. the test applicable to handwash products is the committee european normalisation hygienic handwash test en1499. 170 in this test, e coli is inoculated onto the hands and dried. the handwash product is applied to the hands with a rubbing action for either 30 seconds or 1 minute. the residual number of bacteria present on the hands is assessed pre-and postwash by a rinse sampling process and the log reduction determined. to make a claim that a product is a hygienic handwash, it must produce a log reduction in release of e coli from the hands at least equivalent to that produced by a reference soft soap product (mean, 2.76 log in 1 minute; range, 2.02-4.27). in the united states, handwashing is evaluated by a similar panel test using serratia marcescens as 171 the product, when evaluated by this method, must produce a 2-log reduction after 5 minutes. a range of studies, based on these methodologies, has been carried out to determine the efficacy of handwashing, and are reviewed by boyce and pittet, 172 kampf and kramer, 173 and sickbert-bennet et al. 169 from their assessment, kampf and kramer estimated that handwashing produced a mean reduction of up to 2.4 log within 1 minute. data from individual studies are summarized in table 10 and suggest that, for e coli, the greatest reduction is achieved within the first 30 seconds, ranging from 0.6 to 1.1 log after 15 seconds to 1.8 to 2.8 log after 30 seconds. extending the washing time to 1 minute produces a reduction of 2.6 to 3.23 log, but increasing the process for more than 1 minute does not appear to gain any additional reduction. relatively few data are available on the effectiveness of handwashing in removal of viruses, but the available data (table 10) suggest that handwashing may be less effective for viruses compared with bacteria. although panel test data suggest that handwashing efficacy is similar across a range of bacterial species, some field-based studies suggest that efficacy can vary quite significantly. in some cases, organisms can be attached to the hands too firmly and may not be removed by handwashing. a study of the spread of salmonella and campylobacter from contaminated chickens via hands during handling and preparation in a kitchen 176 showed that, although campylobacter were efficiently released from the hands by a 30second rub and rinse process, a 2-minute process was necessary to eliminate salmonella. the hand rinsing process is also important; cogan et al 86 showed that, following preparation of salmonella and campylobacter-contaminated chickens in domestic kitchens, 15.3% of hands and hand and food contact surfaces still showed evidence of contamination even after participants had carried out a washing-up routine with detergent and hot water and then used a cloth to wipe surfaces. sites contaminated most frequently were hands (20%); dishcloths, utensils, and tap handles (25%); and sink surrounds (30%). these results were confirmed in further studies 176, 177 in which, after cleaning up with a typical routine involving a bowl of hot soapy water and a cloth, although isolation rates from hands of participants were 5% (1/20) for campylobacter, 45% (9/20) of participants still had salmonella on their hands, and, on 3 occasions, counts recovered were .10 3 colony-forming units. in a further study in which participants cleaned up in the same way but then rinsed their hands under running water for 10 seconds, no samples were positive for campylobacter. however, 15% (3/20) still had low numbers of salmonella isolated from their hands. larson et al showed that the quantity of soap (1 ml and 3 ml) used can also have an impact on the microbial reduction achieved by handwashing. 178 bidawid et al 65, 66 studied the impact of handwashing in preventing transfer of hav and fcv from artificially contaminated finger pads to pieces of lettuce (table 11 ). touching the lettuce for 10 seconds resulted in transfer of 9.2% and 18%, respectively, of the virus. when finger pads were washed before the lettuce was touched, the amount of virus transferred was reduced to 0.39% and 0.4%, respectively. amounts of hav and fcv remaining on treated finger pads were 6.5% and 7%, respectively. surprisingly, virus transfer to lettuce when the finger pads were rinsed with water alone was between 0% and 0.3%, depending on the volume of water used for rinsing. barker et al showed that a thorough 1-minute handwash with soap was sufficient to eliminate norovirus from fecally contaminated hands to levels that gave negative reverse-transcription polymerase chain reaction assays. 89 however, schurmann and eggers 175 concluded that enteric viruses, particularly poliovirus, may be more strongly bound to the skin and that the inclusion of an abrasive substance in handwash preparations is needed to achieve effective removal. handwashing was also found to be ineffective in eliminating adenovirus from hands of a physician and patients. 179 for handwashing, a hand-rubbing time of 15 seconds with soap is generally recommended, although the data in table 10 indicate that 30 seconds to 1 minute is needed to achieve the optimum of 2-to 3-log reduction. in practice, it is doubtful whether people comply with even a 15-second handwash, although there are few data to confirm this. a study of 224 healthy another study with 52 office workers and students showed a mean log prewash count of 4.81 compared with 5.07 postwash. 181 kampf and kramer 173 also reviewed studies from health care settings in which increased bacterial counts were found on the hands after handwashing, and handwashing failed to prevent transfer of bacteria from hands to surfaces. although there are no data available to confirm this, increases in contamination may result from sweating induced by hot water, which flushes resident bacteria from the sweat glands onto the hand surface or aids detachment of bacteria attached to skin scales. it is important to bear in mind that, although soap and water removes contamination from the hands, soap itself has a limited antimicrobial effect, which means that contamination will be transferred to the sink. hospital studies show that pseudomonas aeruginosa and burkholderia cepacia 182 can form reservoirs of contamination in sink waste pipes and can be a source of infection at times when splashes of contaminated water come in contact with hands. mermel et al reported that hands of hcws became recontaminated from faucet handles during a shigella outbreak. 183 soap bars also have the potential to spread contamination from person to person via the hands. 88 efficacy of abhs abhs are formulations that contain either ethanol 1propanol or 2-propanol or a combination of these products. their antimicrobial activity is attributed to their ability to denature proteins. although products containing 60% to 95% alcohol are most effective, higher concentrations are less effective because proteins are not easily denatured in the absence of water. a range of in vivo and in vitro studies have been carried out to determine the effectiveness of abhs and are reviewed by boyce and pittet, 172 kampf and kramer, 173 and sickbert-bennet et al. 169 in vivo panel testing of abhs. in europe, the efficacy of abhs is established by panel tests that determine the reduction in the number of organisms released from artificially contaminated hands. the test applicable to abhs is the committee european normalisation hygienic handrub test en1500. 184 in this test, e coli is inoculated onto the hands and dried. the sanitizer is applied to the hands with a rubbing action for a specified period. the residual number of bacteria present on hands is assessed pre-and posttreatment by a rinse-sampling process and the log reduction determined. to claim that a product is a hygienic handrub, it must produce a log reduction at least equivalent to that produced by a reference product containing 60% vol/vol 2-propanol (mean, 4.24 log in 1 minute; range, 3.17-6.46). in vivo panel testing against bacterial strains. data from in vivo panel tests, summarized in table 12 , indicate that abhs show good and rapid activity against bacterial stains such as e coli and s aureus. efficacy is at least as good, if not better, than that achieved by handwashing with soap (table 10) ; log reductions obtained after a 30-second contact period were of the order of 3.4 to 3.7 or more compared with 1.8 to 2.8 for a 30-second handwashing process. boyce and pittet 172 conclude that, typically, log reductions of the release of test bacteria from artificially contaminated hands average 3.5 log after 30 seconds and 4.0 to 5.0 log after 1 minute. paulson et al 185 compared the efficacy of abhs containing 62% ethanol (contact time 5 minutes) with handwashing against s marcescens, which showed that handwashing (20 seconds rubbing followed by 30 seconds rinsing) produced a log reduction of 2.29 compared with 3.83 for the abhs. hammond et al 186 recorded a 2.84-log reduction for 62% ethanol against s marcescens in 10 seconds using the astm method. sickbert-bennet et al, 174 however, showed that exposure of s marcescens to 60% to 62% ethanol for 10 seconds produced only a 1.15-to 1.55-log reduction compared with 1.87-log reduction for handwashing for 10 seconds, when tested by the astm 1147 method. leischner et al 187 carried out in vivo tests that showed that alcohol gels were significantly less effective against c difficile spores (1.68-to 1.94-log reduction) compared with handwashing with chlorhexidine soap (2.46-log reduction). residual spores were readily transferred by handshaking following abhs use. 187 the reduction in spore counts is higher than expected in view of their known resistance to alcohol and may result from the friction associated with application of the gel rather than a bactericidal action; kampf and kramer 173 state that water alone can produce a reduction of 0.5 to 2.8 log within 1 minute for e coli. using the standard astm 1174 method, sickbert-bennet et al evaluated the effect of exposure time and volume of product used on the efficacy of 62% ethanol. 169 they showed that the use of 7 g of the abhs produced a higher log reduction compared with 3 g (2.7-to 3.8-log reduction compared with 1.0-to 1.8log reduction). rubbing the hands until dry (3-12 minutes) was more effective compared with a 10-second application (1.0-to 1.6-log reduction compared with 0.6-to 1.1-log reduction). two recent field studies indicate that an abhs is equally or slightly more effective than handwashing in reducing bacterial contamination on hands. davis et al 19 compared the reduction of bacterial counts on hands using soap and water or a 62% ethanol-based hand sanitizer (contact time 30 seconds) after animal handling at a us livestock event. there was no significant difference in the distribution of log reductions obtained using abhs compared with handwashing; log reductions in total count ranged from 21.4 to 1.4 and 23.0 to 3.5 for total coliforms. traub-dargtz et al carried out a study at 2 clinics in canada to evaluate the efficacy of handwashing compared with use of abhs (62% ethanol, contact time 30-60 seconds) on veterinary staff performing routine equine physical examinations. 188 mean bacterial load on hands increased by 0.36 and 0.91 log (for the 2 clinics, respectively) as a result of handling the animals, whereas the mean log reduction produced by handwashing with soap was less than 0.6, compared with 1.29 and 1.44 log (for the 2 clinics, respectively) produced by abhs. in vivo panel testing against viral strains. a number of in vivo studies have been carried out to determine the efficacy of abhs in reducing the release of viruses from hands. test methods were variants of the method of ansari et al 189 or the astm e1174 method, 171 in which the virus is applied to the fingertips and the efficacy of the product in reducing the numbers of viral particles recoverable from the hands determined. the residual number of viral particles present on the hands is assessed pre-and posttreatment and the log reduction determined. data collated by boyce and pittet 172 (table 13) indicate that ethanol at 60% to 80% produces a 0.8-to .3-log reduction against a range of viruses, the extent of the reduction depending on the viral strain, the nature and concentration of the alcohol, and contact time. data indicate that activity of abhs against viral strains is less than against bacterial strains and that ethanol has greater activity against viruses than 2-propanol. however, all of the strains referred to in table 13 are nonenveloped viruses, which are known to be more resistant to disinfectants than enveloped viruses. as far as hand hygiene in the home and community is concerned, however, this is key because many of the viral strains responsible for hygiene-related id commonly occurring in community settings (rotavirus, norovirus, rhinovirus, and adenovirus) are nonenveloped. that having been said, the data suggest that, although nonenveloped viruses such as hav and enteroviruses (eg, poliovirus) require 70% to 80% alcohol to be reliably inactivated, studies by sattar et al 194 in a number of these studies, handwashing with soap was also investigated. these studies 175, 189, 196 showed that the action of abhs against hav, polio, and rotavirus was significantly better than that achieved by handwashing with soap. however, in the test model used by ansari et al 189 and mbithi et al, 196 inoculated fingertips are exposed to soap solution or abhs by inverting them over a vial containing the product. in practice, handwashing involving rubbing and rinsing is likely to remove larger numbers of organisms from hands. in a further experiment, ansari et al 115 also demonstrated that 2-propanol (70%) was more effective (98.9% reduction after 10 seconds) than liquid soap (77% reduction) against rotavirus. mbithi et al showed that the log reduction of polio and hav virus (0.89-1.34) by application of 70% ethanol was sufficient to prevent transfer to another surface via the fingertips. 196 using similar methodology, bidawid et al 65, 66 studied the impact of ethanol hand sanitizers in preventing transfer of hav and fcv from artificially contaminated finger pads to pieces of lettuce. results (table 11) show that touching the lettuce for 10 seconds resulted in transfer of 9.2% and 18%, respectively, of the virus. when finger pads were treated with 62% ethanol or 75% ethanol (contact time 20 seconds) before the lettuce was touched, the amount of virus transferred was reduced to 0.64% and 0.46%, respectively, for hav and 2.1% and 1.2%, respectively, for fcv. although both 62% and 75% alcohol produced significant reductions in virus transfer, significant amounts of virus were found to remain on treated finger pads. in all cases, treatment with ethanol was less effective than handwashing. kampf and kramer 172 and boyce and pittet 173 suggest that, to achieve satisfactory activity against nonenveloped viruses, higher alcohol concentrations and extended contact times are needed. absolute ethanol reduced viral release from hands by 3.2 log, 80% ethanol by 2.2 log, and absolute 1-propanol by 2.4 log 197 but with a contact time of 10 minutes. schurmann and eggers 175 concluded that high alcohol-concentration products are effective against enteroviruses only under favorable conditions (large disinfectant/ virus volume ratio, low protein load). other studies also demonstrate superior activity of high ethanol concentrations against nonenveloped viruses such as polio, hav, and adenovirus. 198, 199 in vitro testing against bacteria, viruses, and fungi. whereas in vivo tests can be used to indicate the efficacy of products under use conditions, in vitro suspension tests are used to establish whether efficacy extends to a broad range of organisms. in vitro testing bacterial and fungal strains. alcohols have excellent and rapid activity against gram-positive and gram-negative vegetative bacteria and fungi when tested in vitro. 172, 173 a study by fendler et al 200 (table 14) shows the efficacy of an abhs containing 62% ethyl alcohol against a range of bacterial and fungal species, giving 4-to 6-log reduction in 15 to 30 seconds. in vitro testing against viral strains. data, as reviewed by boyce and pittet, 172 confirm that enveloped viruses such as herpes, influenza, piv, and rsv are very susceptible to alcohols. data from individual studies (table 15) suggest that activity against enveloped viruses is equivalent to that against bacterial strains. however, in agreement with in vivo data, alcohols tend to be less effective against nonenveloped viruses, although this is not the case for all strains. fendler et al 200 confirmed good activity for ethanol (62%) against piv and herpes viruses (.4-log reduction in 30 seconds) and some, but relatively less, activity against the nonenveloped rhinovirus, cocksackie virus, adenovirus, and hav (1-to 3-log reduction in 30 seconds). hammond et al 186 showed .5-log reduction against herpes and influenza virus but also .4.25-log reduction against rhinovirus type 16. there are no data on efficacy against rotavirus in vitro. in vitro tests suggest that alcohols are relatively effective against fcv, although gehrke et al 190 (table 15) found that 1-propanol was more effective than 2-propanol and ethanol. it was also found that these alcohols were less effective against fcv at 80% than at 50% and 70%. at this concentration (80%), 1-propanol, 2-propanol, and ethanol produced log reductions of only 1.9, 1.35, and 2.16, respectively. by contrast, duizer et al 201 showed that 70% ethanol produced less than a 2-log reduction for fcv after 8 minutes and a 3-log reduction after 30 minutes. these data are confirmed by a further study (mcneil-ppc unpublished) using in vitro suspension test methods as used to generate data in table 15 . the data (table 16) show that 62% ethanol gave a 3to 6-log reduction in 30 seconds against a range of nonenveloped viruses including not only rsv, piv, and influenza a and b but also against some strains of rhinovirus and echovirus. efficacy of abhs under conditions of soiling. alcohols are considered inappropriate when hands are visibly dirty or soiled because they fail to remove soiling. however, in a number of in vitro studies, in which the efficacy of abhs was determined in the presence and absence of soil (10% fetal calf serum or 0.3% bovine serum albumin), soil produced little or no loss of efficacy. 198, 202 larson and bobo showed that, in the presence of small amounts of protein material (eg, blood), ethanol and 2-propanol were more effective than soap in reducing bacterial counts on hands. 203 using the astm 1174 method, sickbert-bennet et al 169 showed that applying protein to hands did not produce any significant reduction in efficacy of abhs or handwashing but produced a modest but significant increase; log reductions for handwashing were 1.18 to 1.39 and 1.56 to 1.87 in the absence and presence of protein, respectively. log reductions for abhs were 0.18 to 1.07 and 1.35 to 1.55 in the absence and presence of protein, respectively. one of the problems in developing hygiene promotion policies is the lack of quantitative data on the relative health impact of different hygiene interventions. although intervention studies yield quantitative data on health impact, as discussed in section 4.2, the reliability of these estimates is difficult to confirm. by contrast, in vivo and in vitro tests are more economic to perform and can be used to determine relative efficacy of different procedures but give no assessment of how the contamination reduction on hands correlates with health impact. in an attempt to overcome these problems, haas et al have applied the technique of quantitative microbial risk assessment (qmra) to estimate the relative health benefits resulting from use of different hygiene procedures. 204 this approach involves using microbiologic data from the published literature related to each stage of the infection transmission cycle to calculate infection risk. in a recent study, 205 these investigators developed a model for studying the effect of hand contact with ground beef during food preparation, which was used to study the impact of handwashing and use of abhs in preventing subsequent transference from the hands to the mouth compared with no handwashing. pathogenic e coli and e coli o157:h7 were selected for this study because it is known from other investigations 206 that handling ground beef during home food preparation poses a risk of infection with e coli. to perform the risk assessment, data on the density of pathogens in ground beef, transference from beef to hands, removal by handwashing or abhs, rate of transfer from hand to mouth, and infectivity of ingested pathogens were obtained from the literature and, after screening for data quality, were used to develop probability distributions. for assessing log reductions produced by hand hygiene procedures, only in vivo panel testing data were considered. the median log reduction used in these calculations was 0.3 (range, 0.2-3.0) for handwashing and 4.3 (range, 2.6-5.8) for abhs. table 17 shows the estimates of the infection risk from handling raw beef, as obtained from the analysis. the authors note that these risks are conditional in the sense that they quantify the risk to an individual who has handled ground beef and who engages in hand-to-mouth activity. the probability that an individual will engage in such behavior is not known, and, therefore, a direct comparison with actual disease rates cannot be made. however, with some plausible assumptions, it was assessed that, assuming that there are 100 million individuals in the united states, each of whom handles ground beef once per month, this results in 1.2 3 10 9 contacts per year. assuming that 10% of these individuals contact hand to mouth after handling ground beef, this amounts to 1.2 3 10 8 incidents per year. for e coli o157:h7, using the median risk, this would result in an estimate ranging from 0.014 infections per year if all individuals washed their hands with soap following contact with ground beef to 0.7 infections per year if no handwashing is done. this would equate to a 98% median risk reduction for handwashing compared with no handwashing. if an abhs was used, this would result in an estimate of 0.00005 infections per year if all individuals used abhs following contact with ground beef. this would equate to a 99.9996% median risk reduction for use of abhs compared with handwashing. this study follows an earlier study by haas et al 207 to calculate risks associated with hand-to-mouth transfer after diaper changing of a baby infected with shigella. based on this model, it was calculated that the probability of acquiring infection was between 24 of 100 and 91 of 100 for those who used handwashing with soap after changing diapers. this was based on panel test data 205 conclude that quantitative microbial and id risk models offer a useful tool to assess the relative extent to which different hygiene procedures can impact on id risks. they concede, however, that, although risk modeling represents a promising approach, there are limitations to most models because of the multifactorial nature of infection transmission, the dynamic environment in which transmission takes place, and the paucity of data to specify model parameters. in an earlier section, we evaluated intervention study data to assess the strength of the causal link between hand hygiene and id transmission. in this section, we use these data to evaluate the effectiveness of handwashing as a hygiene measure and in relation to the effectiveness of using abhs as an adjunct or an alternative to handwashing. despite the methodologic limitations, the collective weight of evidence from intervention and microbiologic studies described earlier suggests that handwashing with soap can have a significant impact in reducing the incidence of gi and rt infection. the data, however, show that the health impact from handwashing promotion varies significantly according to the setting and outcome. statistically significant reductions ranged from 48% to 57% for gi illness and 20% to 51% for rt illness. although all studies were carried out in settings such as day care centers and schools, we believe that the modes of transmission in these settings and the relative rates of transmission of rt and gi infections are likely to reflect those occurring in the home. in 2004, meadows and le saux published a review of the effect of rinse-free hand sanitizers in elementary schools over a 20-year period. 208 they concluded, however, that the data were of poor quality and that more rigorous intervention trials are needed. in a more recent study, aiello et al examined the epidemiologic evidence for a relationship between waterless hand sanitizers and infections in the community setting over several decades. 154 in table 18 , we present the studies that specifically examined abhs. only studies with an effect estimate and 95% ci are presented. the type and content of the abhs varied across studies, for example, one study reported the use of a 60% isopropyl alcohol rinse and another study utilized an alcohol-based foam sanitizer. however, most studies used alcohol-based gels or other alcohol-based emollients. the alcohol content included ethanol and 2-propanol at concentrations ranging from 60% to 90%. of the 8 intervention studies, 7 were conducted in the united states (88%, 7/8) and 1 in finland (13%). most were conducted in child day care centers, elementary schools, or universities (88%, 7/8), and one was conducted in the household (13%, 1/8). outcomes included gi-related illnesses/symptoms and/or upper rt-related illnesses/symptoms examined as separate outcomes or in combination with other infectionrelated symptoms as part of a school absence-related definition of ''infectious-illness.'' of the 8 studies, 88% (7/8) reported significant results for at least one age group or outcome. the effect was stronger in younger compared with older age groups for studies providing age stratified data. the reduction in gi illness ranged from 0% to 59% for the 4 intervention studies that examined gi illnesses as separate outcomes. [209] [210] [211] 215 of these, all but one showed statistically significant reductions. 210 the study by uhari et al showed a significant reduction in gi illness only among children #3 years of age. 211 all but one of these studies was conducted in child care settings. 215 when evaluated separately, reductions in gi illness appeared more robust compared with the findings for upper rt illness. for upper rt illness, the reduction in infectious illness/symptoms ranged from 26% to 26%. only 2 of the 5 studies (44%) examining upper rt illness as a main outcome reported a statistically significant reduction. uhari et al reported a 13% reduction in rt illnesses among children #3years of age, but no significant effect in older children. 211 white et al reported a 20% reduction in upper rt illness among students using abhs in residence halls. 213 however, this study suffered from several methodologic shortcomings, including lack of control for clustered units, no randomization, no masking, and no monitoring of product use. all but one of the intervention studies included a hygiene education component, but, in 7 of these studies, this was only provided in the intervention arm. the level of education varied widely, ranging from basic information on when to use the abhs (ie, after sneezing and coughing, after use in the restroom, before lunch) to in-depth education programs 214 and biweekly instructional material designed to educate families on hand hygiene and infection transmission. 215 in all studies, abhs was promoted as a supplement to handwashing, or as an alternative to handwashing when soap was unavailable, and it is likely that the hygiene education would have had the effect of encouraging more frequent handwashing as well as use of abhs. although almost all studies indicated that hygiene education combined with promotion of abhs can reduce the risks of gi or rt illness, only 2 studies allowed any assessment of the independent effect of the abhs. of these 2 studies, both studies showed a significant reduction in illness-related absences (20% and 44%, respectively), but it is not clear whether the illnesses were predominantly gi or rt because these studies used a loose definition of absence-related illnesses. sandora et al 215 was the only study carried out in the household setting and, of all the studies, reported the highest reduction for gi illness. the trial involved 292 families with children enrolled in 26 child care centers. intervention families received a supply of abhs and biweekly hand hygiene educational materials for 5 months; control families received only materials promoting good nutrition. a total of 252 gi illnesses occurred during the study; 11% were secondary illnesses. the secondary gi illness rate was significantly lower (59%) in intervention families compared with control families (see table 18 ). a total of 1802 rt illnesses occurred during the study; 25% were secondary illnesses. although rt illness rates were not significantly different between groups, families with higher abhs usage had marginally lower rt illness rate than those with less usage (19% reduction). sandora et al 215 suggested that the difference may be due to heightened diligence associated with using abhs after a gi-related incident compared with an rt incident, such as sneezing. overall, based on relatively limited data available, the results in table 18 suggest that the impact of abhs promotion, as part of a hygiene education and promotion program in reducing the incidence of gi infections in young children, is similar to that observed for promotion of handwashing with soap. promotion of abhs in this manner also produced some reduction in the incidence of rt infections, which was less than that associated with promotion of handwashing alone. assessing whether there might be an added health benefit of using abhs above and beyond the effect of hygiene education is hampered by the fact that most studies used hygiene education and abhs in the intervention arm but did not provide an educational component to the control arm. several important methodologic issues were evident, although more recent studies have improved designs and conduct. in most studies, either parents or school personnel provided information on id among children in the study populations. in all but one study, 34 the parents, participants, or personnel monitoring and reporting infections were not masked as to their own or their child's intervention status. although masking of participants and interviewers to the intervention status is important, because it might influence reporting, it is often difficult to conduct masked hygiene interventions and may not be ethical. sandora et al determined that it was neither feasible nor ethical to mask subjects or interviewers because it is difficult to devise a formulation that could act as a ''placebo'' for abhs, and using a placebo abhs product might endanger the control group via inadequate hand hygiene. 215 in many of the abhs studies, especially the recent ones, efforts were made to control for potential confounding factors. however, many of the studies did not collect information on baseline hand hygiene practices (nor methods and frequency of cleaning/disinfecting soiled/contaminated environmental surfaces in homes) as well as abhs use. the studies also excluded participants who reported current abhs use in the home. furthermore, participants were asked to refrain from using abhs in settings outside the home. these are all important design strategies minimizing bias associated with noncompliance or differential usage. two of the 8 intervention studies failed to use systematic monitoring for hygiene practices, such as frequency of hand-sanitizing episodes, frequency of handwashing, or duration of handwashing. 212, 213 this is especially concerning because the study by sandora et al suggests that the quantity of abhs influences the risk of infection in a dose-response manner. 215 moreover, if frequency of handwashing and abhs use is not recorded, it is impossible to isolate the independent effects of abhs from that of handwashing on infection rates. in these studies of abhs use, surveillance measures included calculating use from monthly demand, total amount supplied, observation by research assistants, participant report, and reported use by primary caregivers in households. 186, 209, 212, 214, 215 overall, the microbiologic data, together with the intervention study data (both those involving abhs as well as those involving handwashing) as presented in this review, provide consistent evidence of a strong causal link between hygiene and the spread of infection in the home and community, and suggest that probably the single most important route for the spread of infection is the hands. if the data from intervention studies (summarized in table 19 ) are an accurate reflection of the true picture, it is suggested that, for up to 60% of gi illnesses, the hands are the ''sufficient,'' or a ''component'' (see earlier for definitions), cause of spread of infection. this correlates with microbiologic and other data reviewed in this report, which suggest that, although there is a tendency to assume that gi infections are mostly foodborne and result from inadequate cooking and inadequate storage of food, in reality, most gi infections in the home result from person-to-person spread or contamination of ready-to-eat foods within the home, much of which involves the hands as the sufficient or a component cause. for rt illnesses, the intervention study data (summarized in table 19 ) suggest that transmission via hands could be a sufficient or component cause of up to 50% of illnesses; whereas there has been a tendency to assume that the lower impact of hand hygiene on rt compared with gi infections is due to the fact that spread of rt pathogens is mainly airborne, the microbiologic and other data in this review correlate with the intervention data in suggesting that, for rt infections commonly circulating in the community, such as rhinovirus and rsv, the hands are the major route of spread. although up to 50% to 60% reduction in id risk was observed in some intervention studies, in other studies the reduction was much less. this variability could well be due to methodologic issues but could also be due to other factors within and between study communities. one possibility is that it relates to differences in the range of pathogens with differing modes of spread prevalent in different study groups, which means that hand hygiene has greater impact in some intervention groups than others. alternatively, the differences may reflect differing levels of hand hygiene compliance in different intervention groups. in some studies, the quality of the hygiene education, the manner in which the hygiene promotion was conducted, and the enthusiasm with which it was received may have given the intervention group a better understanding of what was required, with the result that they used better hygiene technique and were more likely to apply it at critical times. although there are no intervention study data to confirm this, the microbiologic data together with the qmra assessments suggest that even a relatively modest increase in log reduction on hands within a population could produce a significant increase in the health impact of a hand hygiene promotion campaign, which could, in turn, be achieved by addressing the issues in the next 2 sections. although panel tests carried out under controlled conditions showed that handwashing can reduce the numbers of bacteria and some viruses on the hands by up to 2-to 3-log within 30 seconds to 1 minute, in practice it is doubtful whether people wash their hands properly, even for the prescribed period of 15 seconds, to achieve this. at present, there is a paucity of data on the efficacy of handwashing in relation to how people actually wash their hands on a day-to-day basis, both in the duration of handwashing and handwashing technique; in most of the intervention studies described earlier no attempt was made to time handwashes or to determine residual levels of contamination on the hands after handwashing. microbiologic data suggest that, for some pathogens (eg, salmonella), mechanical removal by handwashing alone is inefficient. these data, together with the results of in vivo panel testing of the effectiveness of handwashing and of abhs, as described above, question the efficacy of handwashing in community-based groups and suggest that more work is needed to determine the efficacy of hand hygiene procedures under conditions normally encountered in the home and how hand hygiene procedures could be improved. for abhs, in vivo and in vitro testing suggest that these formulations are highly effective against bacterial pathogens and can produce a 3.5-log reduction on hands within 30 seconds and 4.0-to 5.0-log reduction after a 1-minute application against a wide range of species including salmonella. it is possible, however, that the potential for increased benefits against bacterial infections compared with handwashing may be offset by reduced efficacy against important nonenveloped viruses such as rotavirus, some strains of rhinovirus, and possibly also norovirus. it has been argued that the higher impact of abhs interventions against gi compared with rt infections is due to the fact that rt infections are predominantly viral. however, because the intervention data indicate that handwashing also supports a stronger reduction in gi diseases compared with rt diseases, this seems unlikely. some studies suggest that, to achieve satisfactory activity that includes all types of viruses, higher concentrations up to 80% ethanol should be advised. other studies suggest that the efficacy of abhs may be increased by increasing the volume of agent applied to the hands. 215 in formulating policies for hand hygiene, it would be convenient to be able to define what represents a ''safe'' residual level of contamination on the hands after hand hygiene, ie, sufficient to prevent infection transmission, but, because the infectious dose varies from one species to another and is dependant on the immune status of the recipient, this approach is untenable. the qmra approach, as outlined earlier in this review, however, demonstrates that strategies that produce an increase in the log reduction on hands from 2 to 3 to 4 are accompanied by a significant incremental reduction in the risk of infection in a given population and could thus be worthwhile. this suggests that the health impact from promoting hand hygiene could be increased by developing and promoting procedures for use in the home and community that increase the log reduction of contamination on the hands. this involves identifying products and procedures (both soap-based and waterless products or wipes) that achieve high levels of removal and/or ''kill'' (alone or in combination) of the full range of gram-negative and gram-positive bacteria and enveloped and nonenveloped viruses and that deliver hand hygiene under conditions that people are prepared to employ in their busy and mobile daily lives. it also suggests that, particularly for ''high-risk'' situations as outlined below, there is advantage to be gained by promoting handwashing followed by use of abhs to increase the log reduction. applying hand hygiene at the correct time: the need for hygiene education the data presented in this review suggest that the favorable health impact from promoting hand hygiene could be further increased by getting people to practice hand hygiene not just more frequently but also at the right time. a number of studies show the relatively poor understanding of the principles of hygiene that is present in the community. this may be one of the factors responsible for the higher risk reductions observed in intervention studies of gi compared with rt infections. for example, knowledge regarding the need for handwashing after coughing or sneezing may not be as pervasive as knowledge about handwashing after defecation, and it may be that people understand better when to wash their hands during food-associated activities but not, for example, while handling contaminated tissues. although some intervention studies described in this review involved a component of education, it was not possible to determine the extent to which hygiene education that enhanced people's understanding of infection transmission also enhanced health outcome. because visible soiling is an unreliable indicator of the presence of pathogens on the hands, people are unlikely to wash their hands at the correct time unless they have been taught to do so or have some awareness of the chain of infection transmission in the home, ie, they are aware of when their hands may be contaminated. whereas risks associated with food handling are largely confined to defined periods of time, for rt and skin infections (and person-to-person transmission of gi infection), the risk is ongoing and involves a large proportion of our ongoing daily activities. thus, whereas it is possible for hand hygiene advice associated with food hygiene to be rule based, this is not the case for other types of infections. in the event of a flu pandemic, the advice issued by the uk health protection agency 216 to ''wash hands frequently'' is unlikely to be effective unless people have some idea of the times when their hands are likely to be contaminated with flu virus. although current thinking about hygiene promotion tends toward a view that the most effective way to change behavior is by mass social marketing of single rule-based hygiene messages, 4 the data presented in this review suggest that the complexity and shifting nature of the id threat is such that a rule-based approach to hygiene is inadequate to meet current public health needs. the need is for an approach founded on awareness of the chain of infection transmission and how it differs for different groups of infections. hygiene education needs to be consistently incorporated as part of hand hygiene promotion programs if people are to properly understand the risks and adapt their behavior accordingly. based on the data presented in this review, we propose that, in promoting hand hygiene, significant improvements in health impact could be achieved by giving better guidance to people, first, on how to choose the best methods for hand hygiene (handwashing and/or use of abhs) based on the situation and showing them how to apply it properly and why this is important. secondly, it means stressing when it is important to apply hand hygiene, ie, what are the risk situations or critical control points at which hand hygiene needs to be applied. although the level of risk varies according to the occupants of the home (eg, presence of children, pets, ill people) and their immune status, based on the risk assessment approach as outlined earlier in this review, the critical control points or situations in which hand hygiene is indicated are as follows: d after using the toilet (or disposing of human or animal feces); d after changing a baby's diaper and disposing of the feces; d immediately after handling raw food (eg, chicken, raw meat); d before preparing and handling cooked/ready-to-eat food; d before eating food or feeding children; but also d after contact with contaminated surfaces (eg, rubbish bins, cleaning cloths, food contaminated surfaces); d after handling pets and domestic animals; d after wiping or blowing the nose or sneezing into the hands; d after handling soiled tissues (self or others', eg, children); d after contact with blood or body fluids (eg, vomit and others); d before and after dressing wounds; d before giving care to an ''at-risk'' person; and d after giving care to an infected person. in choosing the appropriate option for hand hygiene, there are 3 possibilities: either handwashing with soap, use of abhs (or other effective waterlessbased sanitizers), or handwashing followed by use of abhs. a possible framework for informing appropriate choice according to the particular situation is outlined in fig 4. this suggests that, in situations in the home and community that are ''standard risk'' (perhaps better described as situations not specifically regarded as ''high risk''), either handwashing or use of abhs may be chosen. within this, however, there are factors that advise, or in some cases dictate, choice, for example, handwashing is only an option when there is access to soap and water, whereas use of abhs is not an option when hands are heavily soiled (although people are likely to choose handwashing in this situation, prompted by the need to ''clean'' their hands). as discussed previously, there will always be situations in the home in which there is increased risk, either because there is a known source of infection or someone who is at increased risk of becoming infected. these situations are summarized in table 20 . these situations may relate to activities that are carried out routinely in the home, such as handling of raw meat and poultry, or involve household members such as pregnant women or young babies who are otherwise healthy but at increased risk of (or from) infection. they also relate to ''nonroutine'' situations such as a person in the home who is infected with a cold, or norovirus or other gi infections, or to situations in which there is someone who is at increased risk of infection as a result of underlying illness, immunosuppressive drug treatment, or needing catheter or wound care. although much of the ''health care'' carried out at home is done by trained caregivers, increasingly, there are situations in the home in which simple but risky actions are carried out by household members. in all of these ''increased risk'' situations, as outlined in table 20 , it is suggested that handwashing followed by use of an abhs should be encouraged. in persuading people to change behavior, one of the key factors is ''removing barriers to action.'' 217 lack of convenient access to a sink is a significant barrier to compliance, and time pressure is a barrier to getting people to wash their hands thoroughly. a key benefit of abhs is that they offer the means to apply hand hygiene in situations in which there is limited or no access to a soap and water. in home care situations, abhs offer an alternative to handwashing in situations in which other pressures mitigate against finding the time to visit the bathroom for handwashing, for example, when caring for a baby in the nursery or a sick person. they also offer a substitute for handwashing in ''out of home'' settings such as offices and public places, such as public transport or animal exhibits, at which access to soap and water is a particular problem and all of which offer frequent opportunities for hand transmission of infection. promoting use of abhs has the potential to get people to undertake hand hygiene more frequently and at critical times. in response to concerns about the possibility of a flu pandemic, the centers for disease control and prevention recommend the use of abhs for use as an alternative to handwashing. 218 in the event of a flu pandemic, it seems particularly important to encourage people to adopt good hand hygiene in public places. in health care settings, links between use of abhs and increased hand hygiene compliance and reduced infection rates has been observed. 219 in applying the framework outlined in fig 4, our intention is that this should not be regarded as an ''either handwashing or abhs'' situation; the fundamental aim should be to encourage more people to undertake hand hygiene procedures wherever possible at critical times. in view of the fact that hands are part of a complex system of infection transmission pathways, it must also be considered whether hand hygiene can, or should, be promoted in isolation. because people are reluctant to comply with handwashing, together with the microbiologic data showing the potential for transfer via hand and food contact surfaces and cloths to hands, which increase as the frequency occurrence of contamination of these surfaces increases, it would seem that, to maximize the health impact from hand hygiene promotion, it should be s56 vol. 35 no. 10 supplement 1 combined with promotion of hygiene in general, including hygienic cleaning of critical surfaces. if nothing else, this could raise awareness that hand contamination can arise from touching apparently clean surfaces. we are concerned that emphasis on handwashing alone without putting it within the context of other aspects of hygiene is encouraging the perception that handwashing is all that is required, ie, ''if you wash your hands you won't get sick.'' the aim of this report has been to review the evidence base for hand hygiene and develop a practical framework from it for promoting an effective approach to hand hygiene in home and community settings. provision of detailed guidelines for hand hygiene is outside the scope of this review. for such guidelines the reader is referred to the ifh guidelines and training resource on home hygiene. as part of its work in promoting home hygiene, the ifh has produced ''guidelines for prevention of infection and cross infection in the domestic environment'' and ''recommendations for selection of suitable hygiene procedures for use in the domestic environment.'' 220, 221 these documents are based on the concept of a risk-based approach and give detailed guidance on hand hygiene in the context of all aspects of home hygiene including food hygiene, general hygiene, personal hygiene, care of pets, and others. most recently, the ifh has also produced a teaching/self-learning resource on home hygiene. 222 this is based on the ifh guidelines and recommendations but is designed to present home hygiene theory and practice in simple practical language that can be understood by those with relative little infection control training or background. infectious diseases circulating in the community remain a significant concern, both in developed and developing countries. the global burden of id accounts for over 13 million deaths annually but, whereas the majority of deaths occurs in the developing world, infection also causes approximately 4% of deaths in developed countries. 223 although mortality from id has declined in the developed world, trends in morbidity suggest a change in the pattern of id rather than declining rates. several demographic, environmental, and health care trends, as reviewed in this report, are combining to make it likely that the threat of id will increase in coming years, rather than decline. one such factor is the rising proportion of the population in the community who are more vulnerable to infection. an important part of current european and us health policy is commitment to shorter hospital stays. a key requirement is to ensure that the increased health provision at home is not accompanied by an increase in id risks; otherwise, the cost savings gained by care in the community are likely to be overridden by costs of rehospitalization. even for the ''healthy community,'' id represents a significant economic burden because of absence from work and school and added health care costs. secondary infections can produce complications, and some infections may be associated with the development of diseases such as cancer or other chronic conditions, which can manifest at a later date. those responsible for ensuring that the public are protected from infection in health care facilities are now realizing that their ability to manage the problem is hampered by spread of pathogens such as mrsa, c difficile, and norovirus in the community and the home, and the number of infected people or carriers who come into their facilities, and are looking for ways to address this by engaging the public to adopt more rigorous standards of hygiene. one of the things that is apparent from newly emerging data, and that is reflected in this review, is the extent to which common infections circulating in the community are hygiene related. this suggests, in turn, that hygiene promotion could have a significant benefit in terms of improved public health and well-being; in particular, the data highlight the extent to which viruses (norovirus, rotavirus, rhinovirus, influenza, and other viruses) are responsible for hygiene-related diseases now circulating in the community. the main conclusions from this review are as follows: d id circulating in the home and community is a serious public health problem in the developed as well as the developing world. d good hygiene practice is key to reducing the burden of id in the home and community. d hand hygiene is a key component of good hygiene practice in the home and community and can produce significant benefits in terms of reducing the incidence of infection, most particularly for gastrointestinal infections but also for respiratory tract and skin infections. d decontamination of hands can be carried out either by handwashing with soap or by the use of waterless hand sanitizers, which achieve a log reduction in bacterial and viral contamination on hands by the removal of contamination or by killing the organisms in situ. the health impact of hand hygiene within a given community can be increased by using products and procedures, either alone or in sequence, that maximize the log reduction of both bacteria and viruses on hands. d the impact of hand hygiene in reducing id risks could be increased by convincing people to apply hand hygiene procedures correctly (eg, wash their hands correctly) and at the correct time. d to optimize health benefits, promotion of hand hygiene must be accompanied by hygiene education and should also involve promotion of other aspects of hygiene, for example, surface and cloth hygiene. this report highlights a number of areas in which additional data are needed: d further studies are needed to characterize the frequency of, and factors associated with, id transmission in noninstitutional settings such as the home. d further studies are needed to assess the relative efficacy of hand hygiene procedures in reducing hand contamination (handwashing with soap and use of abhs, involving different ''contact/application/rinsing'' times, and others). this includes the following: (1) in vivo panel tests to determine the reduction in bacteria and viruses on hands under controlled conditions. committee european normalisation or astm tests now provide standard test models for comparing the efficacy of handwashing with the use of waterless hand sanitizer products, under defined conditions. they provide an economic approach (relative to intervention studies) that can be used, alone or in combination with qmra, to inform hygiene policy and/or the design of intervention studies. 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mothers-in-law can promote behaviour change a multifaceted approach to changing handwashing behaviour guidelines for prevention of infection and cross infection the domestic environment recommendations for selection of suitable hygiene procedures for use in the domestic environment home hygiene-prevention of infection at home: a training resource for carers and their trainers memorandum on the threat posed by infectious diseases. need for reassessment and a new prevention strategy in germany. rudolf schulke foundation. wiesbaden: mph-verlag gmbh the authors thank dr. michele pearson, centers for disease control and prevention, atlanta, ga, for her very valuable and extensive contributions to the preparation of this review. key: cord-276758-k2imddzr authors: siegel, jane d.; rhinehart, emily; jackson, marguerite; chiarello, linda title: 2007 guideline for isolation precautions: preventing transmission of infectious agents in health care settings date: 2007-12-07 journal: am j infect control doi: 10.1016/j.ajic.2007.10.007 sha: doc_id: 276758 cord_uid: k2imddzr nan . clinical syndromes or conditions warranting additional empiric transmission-based precautions pending confirmation of diagnosis table 3 . infection control considerations for highpriority (cdc category a) diseases that may result from bioterrorist attacks or are considered bioterrorist threats table 4 . recommendations for application of standard precautions for the care of all patients in all health care settings table 5 . components of a protective environment 1. the transition of health care delivery from primarily acute care hospitals to other health care settings (eg, home care, ambulatory care, freestanding specialty care sites, long-term care) created a need for recommendations that can be applied in all health care settings using common principles of infection control practice, yet can be modified to reflect setting-specific needs. accordingly, the revised guideline addresses the spectrum of health care delivery settings. furthermore, the term ''nosocomial infections'' is replaced by ''health care-associated infections'' (hais), to reflect the changing patterns in health care delivery and difficulty in determining the geographic site of exposure to an infectious agent and/ or acquisition of infection. 2. the emergence of new pathogens (eg, severe acute respiratory syndrome coronavirus [sars-cov] associated with sars avian influenza in humans), renewed concern for evolving known pathogens (eg, clostridium difficile, noroviruses, communityassociated methicillin-resistant staphylococcus aureus [ca-mrsa]), development of new therapies (eg, gene therapy), and increasing concern for the threat of bioweapons attacks, necessitates addressing a broader scope of issues than in previous isolation guidelines. 3. the successful experience with standard precautions, first recommended in the 1996 guideline, has led to a reaffirmation of this approach as the foundation for preventing transmission of infectious agents in all health care settings. new additions to the recommendations for standard precautions are respiratory hygiene/cough etiquette and safe injection practices, including the use of a mask when performing certain highrisk, prolonged procedures involving spinal canal punctures (eg, myelography, epidural anesthesia). the need for a recommendation for respiratory hygiene/cough etiquette grew out of observations during the sars outbreaks, when failure to implement simple source control measures with patients, visitors, and health care workers (hcws) with respiratory symptoms may have contributed to sars-cov transmission. the recommended practices have a strong evidence base. the continued occurrence of outbreaks of hepatitis b and hepatitis c viruses in ambulatory settings indicated a need to reiterate safe injection practice recommendations as part of standard precautions. the addition of a mask for certain spinal injections grew from recent evidence of an associated risk for developing meningitis caused by respiratory flora. 4. the accumulated evidence that environmental controls decrease the risk of life-threatening fungal infections in the most severely immunocompromised patients (ie, those undergoing allogeneic hematopoietic stem cell transplantation [hsct] ) led to the update on the components of the protective environment (pe). 5. evidence that organizational characteristics (eg, nurse staffing levels and composition, establishment of a safety culture) influence hcws' adherence to recommended infection control practices, and thus are important factors in preventing transmission of infectious agents, led to a new emphasis and recommendations for administrative involvement in the development and support of infection control programs. 6. continued increase in the incidence of hais caused by multidrug-resistant organisms (mdros) in all health care settings and the expanded body of knowledge concerning prevention of transmission of mdros created a need for more specific recommendations for surveillance and control of these pathogens that would be practical and effective in various types of health care settings. this document is intended for use by infection control staff, health care epidemiologists, health care administrators, nurses, other health care providers, and persons responsible for developing, implementing, and evaluating infection control programs for health care settings across the continuum of care. the reader is referred to other guidelines and websites for more detailed information and for recommendations concerning specialized infection control problems. part i reviews the relevant scientific literature that supports the recommended prevention and control practices. as in the 1996 guideline, the modes and factors that influence transmission risks are described in detail. new to the section on transmission are discussions of bioaerosols and of how droplet and airborne transmission may contribute to infection transmission. this became a concern during the sars outbreaks of 2003, when transmission associated with aerosol-generating procedures was observed. also new is a definition of ''epidemiologically important organisms'' that was developed to assist in the identification of clusters of infections that require investigation (ie multidrug-resistant organisms, c difficile). several other pathogens of special infection control interest (ie, norovirus, sars, centers for disease control and prevention [cdc] category a bioterrorist agents, prions, monkeypox, and the hemorrhagic fever viruses) also are discussed, to present new information and infection control lessons learned from experience with these agents. this section of the guideline also presents information on infection risks associated with specific health care settings and patient populations. part ii updates information on the basic principles of hand hygiene, barrier precautions, safe work practices, and isolation practices that were included in previous guidelines. however, new to this guideline is important information on health care system components that influence transmission risks, including those components under the influence of health care administrators. an important administrative priority that is described is the need for appropriate infection control staffing to meet the ever-expanding role of infection control professionals in the complex modern health care system. evidence presented also demonstrates another administrative concern: the importance of nurse staffing levels, including ensuring numbers of appropriately trained nurses in intensive care units (icus) for preventing hais. the role of the clinical microbiology laboratory in supporting infection control is described, to emphasize the need for this service in health care facilities. other factors that influence transmission risks are discussed, including the adherence of hcws to recommended infection control practices, organizational safety culture or climate, and education and training. discussed for the first time in an isolation guideline is surveillance of health care-associated infections. the information presented will be useful to new infection control professionals as well as persons involved in designing or responding to state programs for public reporting of hai rates. part iii describes each of the categories of precautions developed by the health care infection control practices advisory committee (hicpac) and the cdc and provides guidance for their application in various health care settings. the categories of transmission-based precautions are unchanged from those in the 1996 guideline: contact, droplet, and airborne. one important change is the recommendation to don the indicated personal protective equipment (ppe-gowns, gloves, mask) on entry into the patient's room for patients who are on contact and/or droplet precautions, because the nature of the interaction with the patient cannot be predicted with certainty, and contaminated environmental surfaces are important sources for transmission of pathogens. in addition, the pe for patients undergoing allogeneic hsct, described in previous guidelines, has been updated. five tables summarize important information. table 1 provides a summary of the evolution of this document. table 2 gives guidance on using empiric isolation precautions according to a clinical syndrome. table 3 summarizes infection control recommendations for cdc category a agents of bioterrorism. table 4 lists the components of standard precautions and recommendations for their application, and table 5 lists components of the pe. a glossary of definitions used in this guideline also is provided. new to this edition of the guideline is a figure showing the recommended sequence for donning and removing ppe used for isolation precautions to optimize safety and prevent self-contamination during removal. appendix a provides an updated alphabetical list of most infectious agents and clinical conditions for which isolation precautions are recommended. a preamble to the appendix provides a rationale for recommending the use of 1 or more transmission-based precautions in addition to standard precautions, based on a review of the literature and evidence demonstrating a real or potential risk for person-to-person transmission in health care settings. the type and duration of recommended precautions are presented, with additional comments concerning the use of adjunctive measures or other relevant considerations to prevent transmission of the specific agent. relevant citations are included. new to this guideline is a comprehensive review and detailed recommendations for prevention of transmission of mdros. this portion of the guideline was published electronically in october 2006 and updated in november 2006 (siegel jd, rhinehart e, jackson m, chiarello l and hicpac. management of multidrug-resistant organisms in health care settings, 2006; available from http://www.cdc.gov/ ncidod/dhqp/pdf/ar/mdroguideline2006.pdf), and is considered a part of the guideline for isolation precautions. this section provides a detailed review of the complex topic of mdro control in health care settings and is intended to provide a context for evaluation of mdro at individual health care settings. a rationale and institutional requirements for developing an effective mdro control program are summarized. although the focus of this guideline is on measures to prevent transmission of mdros in health care settings, information concerning the judicious use of antimicrobial agents also is presented, because such practices are intricately related to the size of the reservoir of mdros, which in turn influences transmission (eg, colonization pressure). two tables summarize recommended prevention and control practices using 7 categories of interventions to control mdros: administrative measures, education of hcws, judicious antimicrobial use, surveillance, infection control precautions, environmental measures, and decolonization. recommendations for each category apply to and are adapted for the various health care settings. with the increasing incidence and prevalence of mdros, all health care facilities must prioritize effective control of mdro transmission. facilities should identify prevalent mdros at the facility, implement control measures, assess the effectiveness of control programs, and demonstrate decreasing mdro rates. a set of intensified mdro prevention interventions is to be added if the incidence of transmission of a target mdro is not decreasing despite implementation of basic mdro infection control measures, and when the first case of an epidemiologically important mdro is identified within a health care facility. this updated guideline responds to changes in health care delivery and addresses new concerns about transmission of infectious agents to patients and hcws in the united states and infection control. the primary objective of the guideline is to improve the safety of the nation's health care delivery system by reducing the rates of hais. instruct symptomatic persons to cover mouth/nose when sneezing/ coughing; use tissues and dispose in no-touch receptacle; observe hand hygiene after soiling of hands with respiratory secretions; wear surgical mask if tolerated or maintain spatial separation, .3 feet if possible. *during aerosol-generating procedures on patients with suspected or proven infections transmitted by respiratory aerosols (eg, severe acute respiratory syndrome), wear a fittested n95 or higher respirator in addition to gloves, gown, and face/eye protection. -proper construction of windows, doors, and intake and exhaust ports -ceilings: smooth, free of fissures, open joints, crevices -walls sealed above and below the ceiling -if leakage detected, locate source and make necessary repairs d ventilation to maintain $12 air changes/hour d directed air flow; air supply and exhaust grills located so that clean, filtered air enters from one side of the room, flows across the patient's bed, and exits on opposite side of the room d positive room air pressure in relation to the corridor; pressure differential of .2.5 pa (0.01-inch water gauge) d air flow patterns monitored and recorded daily using visual methods (eg, flutter strips, smoke tubes) or a hand-held pressure gauge d self-closing door on all room exits d back-up ventilation equipment (eg, portable units for fans or filters) maintained for emergency provision of ventilation requirements for pe areas, with immediate steps taken to restore the fixed ventilation system d for patients who require both a pe and an airborne infection isolation room (aiir), use an anteroom to ensure proper air balance relationships and provide independent exhaust of contaminated air to the outside, or place a hepa filter in the exhaust duct. (2) reaffirm standard precautions as the foundation for preventing transmission during patient care in all health care settings; (3) reaffirm the importance of implementing transmission-based precautions based on the clinical presentation or syndrome and likely pathogens until the infectious etiology has been determined ( table 2) ; and (4) provide epidemiologically sound and, whenever possible, evidence-based recommendations. this guideline is designed for use by individuals who are charged with administering infection control programs in hospitals and other health care settings. the information also will be useful for other hcws, health care administrators, and anyone needing information about infection control measures to prevent transmission of infectious agents. commonly used abbreviations are provided, and terms used in the guideline are defined in the glossary. medline and pubmed were used to search for relevant studies published in english, focusing on those published since 1996. much of the evidence cited for preventing transmission of infectious agents in health care settings is derived from studies that used ''quasiexperimental designs,'' also referred to as nonrandomized preintervention and postintervention study designs. 2 although these types of studies can provide valuable information regarding the effectiveness of various interventions, several factors decrease the certainty of attributing improved outcome to a specific intervention. these include: difficulties in controlling for important confounding variables, the use of multiple interventions during an outbreak, and results that are explained by the statistical principle of regression to the mean (eg, improvement over time without any intervention). 3 observational studies remain relevant and have been used to evaluate infection control interventions. 4, 5 the quality of studies, consistency of results, and correlation with results from randomized controlled trials, when available, were considered during the literature review and assignment of evidencebased categories (see part iv: recommendations) to the recommendations in this guideline. several authors have summarized properties to consider when evaluating studies for the purpose of determining whether the results should change practice or in designing new studies. 2,6,7 this guideline contains 4 changes in terminology from the 1996 guideline: 1. the term ''nosocomial infection'' is retained to refer only to infections acquired in hospitals. the term ''health care-associated infection'' (hai) is used to refer to infections associated with health care delivery in any setting (eg, hospitals, long-term care facilities, ambulatory settings, home care). this term reflects the inability to determine with certainty where the pathogen was acquired, because patients may be colonized with or exposed to potential pathogens outside of the health care setting before receiving health care, or may develop infections caused by those pathogens when exposed to the conditions associated with delivery of health care. in addition, patients frequently move among the various settings within the health care system. 8 of infectious agents, a susceptible host with a portal of entry receptive to the agent, and a mode of transmission for the agent. this section describes the interrelationship of these elements in the epidemiology of hais. i.b.1. sources of infectious agents. infectious agents transmitted during health care derive primarily from human sources but inanimate environmental sources also are implicated in transmission. human reservoirs include patients, [20] [21] [22] [23] [24] [25] [26] [27] [28] hcws, 17, [29] [30] [31] [32] [33] [34] [35] [36] [37] [38] [39] and household members and other visitors. [40] [41] [42] [43] [44] [45] such source individuals may have active infections, may be in the asymptomatic and/or incubation period of an infectious disease, or may be transiently or chronically colonized with pathogenic microorganisms, particularly in the respiratory and gastrointestinal tracts. other sources of hais are the endogenous flora of patients (eg, bacteria residing in the respiratory or gastrointestinal tract). [46] [47] [48] [49] [50] [51] [52] [53] [54] i.b.2. susceptible hosts. infection is the result of a complex interrelationship between a potential host and an infectious agent. most of the factors that influence infection and the occurrence and severity of disease are related to the host. however, characteristics of the host-agent interaction as it relates to pathogenicity, virulence, and antigenicity also are important, as are the infectious dose, mechanisms of disease production, and route of exposure. 55 there is a spectrum of possible outcomes after exposure to an infectious agent. some persons exposed to pathogenic microorganisms never develop symptomatic disease, whereas others become severely ill and even die. some individuals are prone to becoming transiently or permanently colonized but remain asymptomatic. still others progress from colonization to symptomatic disease either immediately after exposure or after a period of asymptomatic colonization. the immune state at the time of exposure to an infectious agent, interaction between pathogens, and virulence factors intrinsic to the agent are important predictors of an individual's outcome. host factors such as extremes of age and underlying disease (eg, diabetes 56,57 , human immunodeficiency virus/acquired immune deficiency syndrome [hiv/ aids], 58,59 malignancy, and transplantation 18, 60, 61 ) can increase susceptibility to infection, as can various medications that alter the normal flora (eg, antimicrobial agents, gastric acid suppressors, corticosteroids, antirejection drugs, antineoplastic agents, immunosuppressive drugs). surgical procedures and radiation therapy impair defenses of the skin and other involved organ systems. indwelling devices, such as urinary catheters, endotracheal tubes, central venous and arterial catheters, [62] [63] [64] and synthetic implants, facilitate development of hais by allowing potential pathogens to bypass local defenses that ordinarily would impede their invasion and by providing surfaces for development of biofilms that may facilitate adherence of microorganisms and protect from antimicrobial activity. 65 some infections associated with invasive procedures result from transmission within the health care facility; others arise from the patient's endogenous flora. 46 clothing, uniforms, laboratory coats, or isolation gowns used as ppe may become contaminated with potential pathogens after care of a patient colonized or infected with an infectious agent, (eg, mrsa, 88 vancomycin-resistant enterococci [vre], 89 and c difficile 90 ). although contaminated clothing has not been implicated directly in transmission, the potential exists for soiled garments to transfer infectious agents to successive patients. i.b.3.b. droplet transmission. droplet transmission is technically a form of contact transmission; some infectious agents transmitted by the droplet route also may be transmitted by direct and indirect contact routes. however, in contrast to contact transmission, respiratory droplets carrying infectious pathogens transmit infection when they travel directly from the respiratory tract of the infectious individual to susceptible mucosal surfaces of the recipient, generally over short distances, necessitating facial protection. respiratory droplets are generated when an infected person coughs, sneezes, or talks 91, 92 or during such procedures as suctioning, endotracheal intubation, [93] [94] [95] [96] cough induction by chest physiotherapy, 97 and cardiopulmonary resuscitation. 98, 99 evidence for droplet transmission comes from epidemiologic studies of disease outbreaks, [100] [101] [102] [103] from experimental studies, 104 and from information on aerosol dynamics. 91, 105 studies have shown that the nasal mucosa, conjunctivae, and, less frequently, the mouth are susceptible portals of entry for respiratory viruses. 106 the maximum distance for droplet transmission is currently unresolved; pathogens transmitted by the droplet route have not been transmitted through the air over long distances, in contrast to the airborne pathogens discussed below. historically, the area of defined risk has been a distance of , 3 feet around the patient, based on epidemiologic and simulated studies of selected infections. 103, 104 using this distance for donning masks has been effective in preventing transmission of infectious agents through the droplet route. however, experimental studies with smallpox 107,108 and investigations during the global sars outbreaks of 2003 101 suggest that droplets from patients with these 2 infections could reach persons located 6 feet or more from their source. it is likely that the distance that droplets travel depends on the velocity and mechanism by which respiratory droplets are propelled from the source, the density of respiratory secretions, environmental factors (eg, temperature, humidity), and the pathogen's ability to maintain infectivity over that distance. 105 thus, a distance of , 3 feet around the patient is best considered an example of what is meant by ''a short distance from a patient'' and should not be used as the sole criterion for determining when a mask should be donned to protect from droplet exposure. based on these considerations, it may be prudent to don a mask when within 6 to 10 feet of the patient or on entry into the patient's room, especially when exposure to emerging or highly virulent pathogens is likely. more studies are needed to gain more insight into droplet transmission under various circumstances. droplet size is another variable under investigation. droplets traditionally have been defined as being . 5 mm in size. droplet nuclei (ie, particles arising from desiccation of suspended droplets) have been associated with airborne transmission and defined as , 5 mm in size, 105 a reflection of the pathogenesis of pulmonary tuberculosis that is not generalizeable to other organisms. observations of particle dynamics have demonstrated that a range of droplet sizes, including those of diameter $ 30 mm, can remain suspended in the air. 109 the behavior of droplets and droplet nuclei affect recommendations for preventing transmission. whereas fine airborne particles containing pathogens that are able to remain infective may transmit infections over long distances, requiring aiir to prevent its dissemination within a facility; organisms transmitted by the droplet route do not remain infective over long distances and thus do not require special air handling and ventilation. examples of infectious agents transmitted through the droplet route include b pertussis, 110 influenza virus, 23 adenovirus, 111 rhinovirus, 104 mycoplasma pneumoniae, 112 sars-cov, 21, 96, 113 group a streptococcus, 114 and neisseria meningitides. 95, 103, 115 although rsv may be transmitted by the droplet route, direct contact with infected respiratory secretions is the most important determinant of transmission and consistent adherence to standard precautions plus contact precautions prevents transmission in health care settings. 24, 116, 117 rarely, pathogens that are not transmitted routinely by the droplet route are dispersed into the air over short distances. for example, although s aureus is transmitted most frequently by the contact route, viral upper respiratory tract infection has been associated with increased dispersal of s aureus from the nose into the air for a distance of 4 feet under both outbreak and experimental conditions; this is known as the ''cloud baby'' and ''cloud adult'' phenomenon. [118] [119] [120] i.b.3.c. airborne transmission. airborne transmission occurs by dissemination of either airborne droplet nuclei or small particles in the respirable size range containing infectious agents that remain infective over time and distance (eg, spores of aspergillus spp and m tuberculosis). microorganisms carried in this manner may be dispersed over long distances by air currents and may be inhaled by susceptible individuals who have not had face-to-face contact with (or even been in the same room with) the infectious individual. [121] [122] [123] [124] preventing the spread of pathogens that are transmitted by the airborne route requires the use of special air handling and ventilation systems (eg, aiirs) to contain and then safely remove the infectious agent. 11, 12 infectious agents to which this applies include m tuberculosis, 124-127 rubeola virus (measles), 122 and varicella-zoster virus (chickenpox). 123 in addition, published data suggest the possibility that variola virus (smallpox) may be transmitted over long distances through the air under unusual circumstances, and aiirs are recommended for this agent as well; however, droplet and contact routes are the more frequent routes of transmission for smallpox. 108, 128, 129 in addition to aiirs, respiratory protection with a national institute for occupational safety and health (niosh)-certified n95 or higher-level respirator is recommended for hcws entering the aiir, to prevent acquisition of airborne infectious agents such as m tuberculosis. 12 for certain other respiratory infectious agents, such as influenza 130, 131 and rhinovirus, 104 and even some gastrointestinal viruses (eg, norovirus 132 and rotavirus 133 ) , there is some evidence that the pathogen may be transmitted through small-particle aerosols under natural and experimental conditions. such transmission has occurred over distances . 3 feet but within a defined air space (eg, patient room), suggesting that it is unlikely that these agents remain viable on air currents that travel long distances. aiirs are not routinely required to prevent transmission of these agents. additional issues concerning small-particle aerosol transmission of agents that are most frequently transmitted by the droplet route are discussed below. although sars-cov is transmitted primarily by contact and/or droplet routes, airborne transmission over a limited distance (eg, within a room) has been suggested, although not proven. [134] [135] [136] [137] [138] [139] [140] [141] this is true of other infectious agents as well, such as influenza virus 130 and noroviruses. 132, 142, 143 influenza viruses are transmitted primarily by close contact with respiratory droplets, 23, 102 and acquisition by hcws has been prevented by droplet precautions, even when positive-pressure rooms were used in one center. 144 however, inhalational transmission could not be excluded in an outbreak of influenza in the passengers and crew of an aircraft. 130 observations of a protective effect of ultraviolet light in preventing influenza among patients with tuberculosis during the influenza pandemic of 1957-1958 have been used to suggest airborne transmission. 145, 146 in contrast to the strict interpretation of an airborne route for transmission (ie, long distances beyond the patient room environment), short-distance transmission by small-particle aerosols generated under specific circumstances (eg, during endotracheal intubation) to persons in the immediate area near the patient also has been demonstrated. aerosolized particles , 100 mm in diameter can remain suspended in air when room air current velocities exceed the terminal settling velocities of the particles. 109 sars-cov transmission has been associated with endotracheal intubation, noninvasive positive pressure ventilation, and cardiopulmonary resuscitation. 93, 94, 96, 98, 141 although the most frequent routes of transmission of noroviruses are contact and foodborne and waterborne routes, several reports suggest that noroviruses also may be transmitted through aerosolization of infectious particles from vomitus or fecal material. 142, 143, 147, 148 it is hypothesized that the aerosolized particles are inhaled and subsequently swallowed. roy this conceptual framework can explain rare occurrences of airborne transmission of agents that are transmitted most frequently by other routes (eg, smallpox, sars, influenza, noroviruses). concerns about unknown or possible routes of transmission of agents associated with severe disease and no known treatment often result in the adoption of overextreme prevention strategies, and recommended precautions may change as the epidemiology of an emerging infection becomes more well defined and controversial issues are resolved. i.b.3.d.ii. transmission from the environment. some airborne infectious agents are derived from the environment and do not usually involve person-to-person transmission; for example, anthrax spores present in a finely milled powdered preparation can be aerosolized from contaminated environmental surfaces and inhaled into the respiratory tract. 150, 151 spores of environmental fungi (eg, aspergillus spp) are ubiquitous in the environment and may cause disease in immunocompromised patients who inhale aerosolized spores (through, eg, construction dust). 152, 153 as a rule, neither of these organisms is subsequently transmitted from infected patients; however, there is 1 well-documented report of person-to-person transmission of aspergillus sp in the icu setting that was most likely due to the aerosolization of spores during wound debridement. 154 the pe involves isolation practices designed to decrease the risk of exposure to environmental fungal agents in allogeneic hsct patients. 11, 14, 15, [155] [156] [157] [158] environmental sources of respiratory pathogens (eg, legionella) transmitted to humans through a common aerosol source is distinct from direct patient-to-patient transmission. i.b.3.e. other sources of infection. sources of infection transmission other than infectious individuals include those associated with common environmental sources or vehicles (eg, contaminated food, water, or medications, such as intravenous fluids). although aspergillus spp have been recovered from hospital water systems, 159 the role of water as a reservoir for immunosuppressed patients remains unclear. vectorborne transmission of infectious agents from mosquitoes, flies, rats, and other vermin also can occur in health care settings. prevention of vectorborne transmission is not addressed in this document. this section discusses several infectious agents with important infection control implications that either were not discussed extensively in previous isolation s80 vol. 35 no. 10 supplement 2 guidelines or have emerged only recently. included are epidemiologically important organisms (eg, c difficile), agents of bioterrorism, prions, sars-cov, monkeypox, noroviruses, and the hemorrhagic fever viruses (hfvs). experience with these agents has broadened the understanding of modes of transmission and effective preventive measures. these agents are included for information purposes and, for some (ie, sars-cov, monkeypox), to highlight the lessons that have been learned about preparedness planning and responding effectively to new infectious agents. i.c.1. epidemiologically important organisms. under defined conditions, any infectious agent transmitted in a health care setting may become targeted for control because it is epidemiologically important. c difficile is specifically discussed below because of its current prevalence and seriousness in us health care facilities. in determining what constitutes an ''epidemiologically important organism,'' the following criteria apply: d a propensity for transmission within health care facilities based on published reports and the occurrence of temporal or geographic clusters of more than 2 patients, (eg, c difficile, norovirus, rsv, influenza, rotavirus, enterobacter spp, serratia spp, group a streptococcus). a single case of health care-associated invasive disease caused by certain pathogens (eg, group a streptococcus postoperatively, 160 in a burn unit, 161 or in a ltcf; 162 legionella spp, 14, 163 aspergillus spp 164 ) is generally considered a trigger for investigation and enhanced control measures because of the risk of additional cases and the severity of illness associated with these infections. i.c.1.a. clostridium difficile. c difficile is a sporeforming gram-positive anaerobic bacillus that was first isolated from stools of neonates in 1935 165 and identified as the most frequent causative agent of antibioticassociated diarrhea and pseudomembranous colitis in 1977. 166 this pathogen is a major cause of health care-associated diarrhea and has been responsible for many large outbreaks in health care settings that have proven extremely difficult to control. important factors contributing to health care-associated outbreaks include environmental contamination, persistence of spores for prolonged periods, resistance of spores to routinely used disinfectants and antiseptics, hand carriage by hcws to other patients, and exposure of patients to frequent courses of antimicrobial agents. 167 antimicrobials most frequently associated with increased risk of c difficile include third-generation cephalosporins, clindamycin, vancomycin, and fluoroquinolones. since 2001, outbreaks and sporadic cases of c difficile with increased morbidity and mortality have occurred in several us states, canada, england, and the netherlands. [168] [169] [170] [171] [172] the same strain of c difficile has been implicated in all of these outbreaks; 173 this strain, toxinotype iii, north american pulsedfield gel electrophoresis (pfge) type 1, and polymerase chain reaction (pcr)-ribotype 027 (nap1/027), has been found to hyperproduce toxin a (a 16-fold increase) and toxin b (a 23-fold increase) compared with isolates from 12 other pfge types. a recent survey of us infectious disease physicians found that 40% of the respondents perceived recent increases in the incidence and severity of c difficile disease. 174 standardization of testing methodology and surveillance definitions is needed for accurate comparisons of trends in rates among hospitals. 175 it is hypothesized that the incidence of disease and apparent heightened transmissibility of this new strain may be due, at least in part, to the greater production of toxins a and b, increasing the severity of diarrhea and producing more environmental contamination. considering the greater morbidity, mortality, length of stay, and costs associated with c difficile disease in both acute care and long-term care facilities, control of this pathogen is becoming increasingly important. prevention of transmission focuses on syndromic application of contact precautions for patients with diarrhea, accurate identification of affected patients, environmental measures (eg, rigorous cleaning of patient rooms), and consistent hand hygiene. using soap and water rather than alcohol-based handrubs for mechanical removal of spores from hands and using a bleachcontaining disinfectant (5000 ppm) for environmental disinfection may be valuable in cases of transmission in health care facilities. appendix a provides for recommendations. i.c.1.b. multidrug-resistant organisms. in general, mdros are defined as microorganisms-predominantly bacteria-that are resistant to 1 or more classes of antimicrobial agents. 176 although the names of certain mdros suggest resistance to only a single agent (eg, mrsa, vre), these pathogens are usually resistant to all but a few commercially available antimicrobial agents. this latter feature defines mdros that are considered to be epidemiologically important and deserve special attention in health care facilities. 177 other mdros of current concern include multidrug-resistant streptococcus pneumoniae, which is resistant to penicillin and other broad-spectrum agents such as macrolides and fluroquinolones, multidrug-resistant gram-negative bacilli (mdr-gnb), especially those producing esbls; and strains of s aureus that are intermediate or resistant to vancomycin (ie, visa and vrsa). mdros are transmitted by the same routes as antimicrobial susceptible infectious agents. patient-to-patient transmission in health care settings, usually via hands of hcws, has been a major factor accounting for the increase in mdro incidence and prevalence, especially for mrsa and vre in acute care facilities. [199] [200] [201] preventing the emergence and transmission of these pathogens requires a comprehensive approach that includes administrative involvement and measures (eg, nurse staffing, communication systems, performance improvement processes to ensure adherence to recommended infection control measures), education and training of medical and other hcws, judicious antibiotic use, comprehensive surveillance for targeted mdros, application of infection control precautions during patient care, environmental measures (eg, cleaning and disinfection of the patient care environment and equipment, dedicated single-patient use of noncritical equipment), and decolonization therapy when appropriate. the prevention and control of mdros is a national priority, one that requires that all health care facilities and agencies assume responsibility and participate in community-wide control programs. 176, 177 a detailed discussion of this topic and recommendations for prevention published in 2006 is available at http:// www.cdc.gov/ncidod/dhqp/pdf/ar/mdroguideline2006. pdf. i.c.2. agents of bioterrorism. the cdc has designated the agents that cause anthrax, smallpox, plague, tularemia, viral hemorrhagic fevers, and botulism as category a (high priority), because these agents can be easily disseminated environmentally and/or transmitted from person to person, can cause high mortality and have the potential for major public health impact, might cause public panic and social disruption, and necessitate special action for public health preparedness. 202 general information relevant to infection control in health care settings for category a agents of bioterrorism is summarized in table 3 . (see http:// www.bt.cdc.gov for additional, updated category a agent information as well as information concerning category b and c agents of bioterrorism and updates.) category b and c agents are important but are not as readily disseminated and cause less morbidity and mortality than category a agents. health care facilities confront a different set of issues when dealing with a suspected bioterrorism event compared with other communicable diseases. an understanding of the epidemiology, modes of transmission, and clinical course of each disease, as well as carefully drafted plans that specify an approach and relevant websites and other resources for disease-specific guidance to health care, administrative, and support personnel, are essential for responding to and managing a bioterrorism event. infection control issues to be addressed include (1) identifying persons who may be exposed or infected; (2) preventing transmission among patients, hcws, and visitors; (3) providing treatment, chemoprophylaxis, or vaccine to potentially large numbers of people; (4) protecting the environment, including the logistical aspects of securing sufficient numbers of aiirs or designating areas for patient cohorts when an insufficient number of aiirs is available; (5) providing adequate quantities of appropriate ppe; and (6) identifying appropriate staff to care for potentially infectious patients (eg, vaccinated hcws for care of patients with smallpox). the response is likely to differ for exposures resulting from an intentional release compared with a naturally occurring disease because of the large number of persons that can be exposed at the same time and possible differences in pathogenicity. various sources offer guidance for the management of persons exposed to the most likely agents of bioterrorism. federal agency websites (eg, http://www. usamriid.army.mil/publications/index.html and http:// www.bt.cdc.gov) and state and county health department websites should be consulted for the most upto-date information. sources of information on specific agents include anthrax, 203 smallpox, [204] [205] [206] plague, 207,208 botulinum toxin, 209 tularemia, 210 and hemorrhagic fever viruses. 211, 212 i.c.2.a. pre-event administration of smallpox (vaccinia) vaccine to health care workers. vaccination of hcwsl in preparation for a possible smallpox exposure has important infection control implications. [213] [214] [215] these include the need for meticulous screening for vaccine contraindications in persons at increased risk for adverse vaccinia events; containment and monitoring of the vaccination site to prevent transmission in the health care setting and at home; and management of patients with vaccinia-related adverse events. 216, 217 the pre-event us smallpox vaccination program of 2003 is an example of the effectiveness of carefully developed recommendations for both screening potential vaccinees for contraindications and vaccination site care and monitoring. between december 2002 and february 2005, approximately 760,000 individuals were vaccinated in the department of defense and 40,000 in the civilian or public health populations, including approximately 70,000 who worked in health care settings. no cases of eczema vaccinatum, progressive vaccinia, fetal vaccinia, or contact transfer of vaccinia were reported in health care settings or in military workplaces. 218, 219 outside the health care setting, there were 53 cases of contact transfer from military vaccinees to close personal contacts (eg, bed partners or contacts during participation in sports such as wrestling 220 ). all contact transfers were from individuals who were not following recommendations to cover their vaccination sites. vaccinia virus was confirmed by culture or pcr in 30 cases, 2 of which resulted from tertiary transfer. all recipients, including 1 breast-fed infant, recovered without complications. subsequent studies using viral culture and pcr techniques have confirmed the effectiveness of semipermeable dressings to contain vaccinia. [221] [222] [223] [224] this experience emphasizes the importance of ensuring that newly vaccinated hcws adhere to recommended vaccination site care, especially those caring for high-risk patients. recommendations for pre-event smallpox vaccination of hcws and vacciniarelated infection control recommendations are published in the morbidity and mortality weekly report, 216, 225 with updates posted on the cdc's bioterrorism website. 205 i.c.3. prions. creutzfeldt-jakob disease (cjd) is a rapidly progressive, degenerative neurologic disorder of humans, with an incidence in the united states of approximately 1 person/million population/year. 226, 227 cjd is believed to be caused by a transmissible proteinaceous infectious agent known as a prion. infectious prions are isoforms of a host-encoded glycoprotein known as the prion protein. the incubation period (ie, time between exposure and and onset of symptoms) varies from 2 years to many decades. however, death typically occurs within 1 year of the onset of symptoms. approximately 85% of cjd cases occur sporadically with no known environmental source of infection, and 10% of cases are familial. iatrogenic transmission has occurred, with most cases resulting from treatment with human cadaver pituitary-derived growth hormone or gonadotropin, 228, 229 from implantation of contaminated human dura mater grafts, 230 or from corneal transplants. 231 transmission has been linked to the use of contaminated neurosurgical instruments or stereotactic electroencephalogram electrodes. [232] [233] [234] [235] prion diseases in animals include scrapie in sheep and goats, bovine spongiform encephalopathy (bse, or ''mad cow disease'') in cattle, and chronic wasting disease in deer and elk. 236 bse, first recognized in the united kingdom in 1986, was associated with a major epidemic among cattle that had consumed contaminated meat and bone meal. the possible transmission of bse to humans causing variant cjd (vcjd) was first described in 1996 and was subsequently found to be associated with consumption of bse-contaminated cattle products primarily in the united kingdom. there is strong epidemiologic and laboratory evidence for a causal association between the causative agent of bse and vcjd. 237 although most cases of vcjd have been reported from the united kingdom, a few cases also have been reported from europe, japan, canada, and the united states. most persons affected with vcjd worldwide lived in or visited the united kingdom during the years of a large outbreak of bse (1980) (1981) (1982) (1983) (1984) (1985) (1986) (1987) (1988) (1989) (1990) (1991) (1992) (1993) (1994) (1995) (1996) and may have consumed contaminated cattle products during that time (see http://www.cdc.gov/ncidod/ diseases/cjd/cjd.htm). although there has been no indigenously acquired vcjd in the united states, the sporadic occurrence of bse in cattle in north america has heightened awareness of the possibility that such infections could occur and have led to increased surveillance activities. updated information may be found at http://www.cdc.gov/ncidod/diseases/cjd/cjd.htm. the public health impact of prion diseases has been reviewed previously. 238 vcjd in humans has different clinical and pathologic characteristics than sporadic or classic cjd, 239 including (1) younger median age at death (28 [range, 16 to 48] vs 68 years), (2) longer median duration of illness (14 months vs 4 to 6 months), (3) increased frequency of sensory symptoms and early psychiatric symptoms with delayed onset of frank neurologic signs; and (4) detection of prions in tonsillar and other lymphoid tissues, not present in sporadic cjd. 240 similar to sporadic cjd, there have been no reported cases of direct human-tohuman transmission of vcjd by casual or environmental contact, droplet, or airborne routes. ongoing blood safety surveillance in the united states has not detected sporadic cjd transmission through blood transfusion; 241-243 however, bloodborne transmission of vcjd is believed to have occurred in 2 patients in the uited kingdom. 244, 245 the following fda websites provide information on steps currently being taken in the united states to protect the blood supply from cjd and vcjd: http://www.fda.gov/cber/gdlns/cjdvcjd.htm and http:// www.fda.gov/cber/gdlns/cjdvcjdq&a.htm. standard precautions are used when caring for patients with suspected or confirmed cjd or vcjd. however, special precautions are recommended for tissue handling in the histology laboratory and for conducting an autopsy, embalming, and coming into contact with a body that has undergone autopsy. 246 recommendations for reprocessing surgical instruments to prevent transmission of cjd in health care settings have been published by the world health organization (who) and are currently under review at the cdc. questions may arise concerning notification of patients potentially exposed to cjd or vcjd through contaminated instruments and blood products from patients with cjd or vcjd or at risk of having vcjd. the risk of transmission associated with such exposures is believed to be extremely low but may vary based on the specific circumstance. therefore, consultation on appropriate options is advised. the united kingdom has developed several documents that clinicians and patients in the united states may find useful (see http://www.hpa.org.uk/infections/topics_az/cjd/ information_documents.htm). i.c.4. severe acute respiratory syndrome. sars is a newly discovered respiratory disease that emerged in china late in 2002 and spread to several countries. 135, 140 in particular, mainland china, hong kong, hanoi, singapore, and toronto have been significantly affected. sars is caused by sars-cov, a previously unrecognized member of the coronavirus family. 247, 248 the incubation period from exposure to the onset of symptoms is typically 2 to 7 days, but can be as long as 10 days and in rare cases even longer. 249 the illness is initially difficult to distinguish from other common respiratory infections. signs and symptoms usually include fever above 38.08c and chills and rigors, sometimes accompanied by headache, myalgia, and mild to severe respiratory symptoms. a radiographic profile of atypical pneumonia is an important clinical indicator of possible sars. compared with adults, children are affected less frequently, have milder disease, and are less likely to transmit sars-cov. 135, [249] [250] [251] the overall case fatality rate is approximately 6%; underlying disease and advanced age increase the risk of mortality (see http://www.who.int/csr/sarsarchive/2003_05_07a/en/). outbreaks in health care settings, with transmission to large numbers of hcws and patients, haa been a striking feature of sars; undiagnosed infectious patients and visitors have been important initiators of these outbreaks. 21, [252] [253] [254] the relative contribution of potential modes of transmission is not known precisely. there is ample evidence for droplet and contact transmission; 96, 101, 113 however, opportunistic airborne transmission cannot be excluded. 101, [135] [136] [137] [138] [139] 149, 254 for example, exposure to aerosol-generating procedures (eg, endotracheal intubation, suctioning) has been associated with transmission of infection to large numbers of hcws outside of the united states. 93, 94, 96, 98, 253 therefore, aerosolization of small infectious particles generated during these and other similar procedures could be a risk factor for transmission to others within a multibed room or shared airspace. a review of the infection control literature generated from the sars outbreaks of 2003 concluded that the greatest risk of transmission is to those who have close contact, are not properly trained in use of protective infection control procedures, and do not consistently use ppe, and that n95 or higher-level respirators may offer additional protection to those exposed to aerosol-generating procedures and high-risk activities. 255, 256 organizational and individual factors that affect adherence to infection control practices for sars also were identified. 256 control of sars requires a coordinated, dynamic response by multiple disciplines in a health care setting. 9 early detection of cases is accomplished by screening persons with symptoms of a respiratory infection for history of travel to areas experiencing community transmission or contact with sars patients, followed by implementation of respiratory hygiene/cough etiquette (ie, placing a mask over the patient's nose and mouth) and physical separation from other patients in common waiting areas. the precise combination of precautions to protect hcws has not yet been determined. at the time of this publication, the cdc recommends standard precautions, with emphasis on the use of hand hygiene; contact precautions, with emphasis on environmental cleaning due to the detection of sars-cov rna by pcr on surfaces in rooms occupied by sars patients; 138, 254, 257 and airborne precautions, including use of fit-tested niosh-approved n95 or higher-level respirators and eye protection. 258 in hong kong, the use of droplet and contact precautions, including the use of a mask but not a respirator, was effective in protecting hcws. 113 however, in toronto, consistent use of an n95 respirator was found to be slightly more protective than a mask. 93 it is noteworthy that no transmission of sars-cov to public hospital workers occurred in vietnam despite inconsistent use of infection control measures, including use of ppe, which suggests other factors (eg, severity of disease, frequency of high-risk procedures or events, environmental features) may influence opportunities for transmission. 259 sars-cov also has been transmitted in the laboratory setting through breaches in recommended laboratory practices. research laboratories in which sars-cov was under investigation were the source of most cases reported after the first series of outbreaks in the winter and spring of 2003. 260 lessons learned from the sars outbreaks are useful in devising plans to respond to future public health crises, such as pandemic influenza and bioterrorism events. surveillance for cases among patients and hcws, ensuring availability of adequate supplies and staffing, and limiting access to health care facilities were important factors in the response to sars. 9 guidance for infection control precautions in various settings is available at http://www.cdc.gov/ncidod/sars. i.c.5. monkeypox. monkeypox is a rare viral disease found mostly in the rain forest countries of central and west africa. the disease is caused by an orthopoxvirus that is similar in appearance to smallpox but causes a milder disease. the only recognized outbreak of human monkeypox in the united states was detected in june 2003, after several people became ill after contact with sick pet prairie dogs. infection in the prairie dogs was subsequently traced to their contact with a shipment of animals from africa, including giant gambian rats. 262 this outbreak demonstrates the importance of recognition and prompt reporting of unusual disease presentations by clinicians to enable prompt identification of the etiology, as well as the potential of epizootic diseases to spread from animal reservoirs to humans through personal and occupational exposure. 263 only limited data on transmission of monkeypox are available. transmission from infected animals and humans is believed to occur primarily through direct contact with lesions and respiratory secretions; airborne transmission from animals to humans is unlikely but cannot be excluded, and may have occurred in veterinary practices (eg, during administration of nebulized medications to ill prairie dogs 264 ). in humans, 4 instances of monkeypox transmission in hospitals have been reported in africa among children, usually related to sharing the same ward or bed. 265, 266 additional recent literature documents transmission of congo basin monkeypox in a hospital compound for an extended number of generations. 267 there has been no evidence of airborne or any other person-to-person transmission of monkeypox in the united states, and no new cases of monkeypox have been identified since the outbreak in june 2003. 268 the outbreak strain is a clade of monkeypox distinct from the congo basin clade and may have different epidemiologic properties (including human-to-human transmission potential) from monkeypox strains of the congo basin; 269 this awaits further study. smallpox vaccine is 85% protective against congo basin monkeypox. 270 because there is an associated case fatality rate of , 10%, administration of smallpox vaccine within 4 days to individuals who have had direct exposure to patients or animals with monkeypox is a reasonable policy. 271 for the most current information on monkeypox, see http://www.cdc.gov/ncidod/mon keypox/clinicians.htm. i.c.6. noroviruses. noroviruses, formerly referred to as norwalk-like viruses, are members of the caliciviridae family. these agents are transmitted via contaminated food or water and from person to person, causing explosive outbreaks of gastrointestinal disease. 272 environmental contamination also has been documented as a contributing factor in ongoing transmission during outbreaks. 273, 274 although noroviruses cannot be propagated in cell culture, dna detection by molecular diagnostic techniques has brought a greater appreciation of their role in outbreaks of gastrointestinal disease. 275 reported outbreaks in hospitals, 132 148 and large crowded shelters established for hurricane evacuees 285 has demonstrated their highly contagious nature, their potentially disruptive impact in health care facilities and the community, and the difficulty of controlling outbreaks in settings in which people share common facilites and space. of note, there is nearly a 5-fold increase in the risk to patients in outbreaks when a patient is the index case compared with exposure of patients during outbreaks when a staff member is the index case. 286 the average incubation period for gastroenteritis caused by noroviruses is 12 to 48 hours, and the clinical course lasts 12 to 60 hours. 272 illness is characterized by acute onset of nausea, vomiting, abdominal cramps, and/or diarrhea. the disease is largely self-limited; rarely, death due to severe dehydration can occur, particularly in elderly persons with debilitating health conditions. the epidemiology of norovirus outbreaks shows that even though primary cases may result from exposure to a fecally contaminated food or water, secondary and tertiary cases often result from person-to-person transmission facilitated by contamination of fomites 272, 287 and dissemination of infectious particles, especially during the process of vomiting. 132, 142, 143, 147, 148, 272, 278, 279 widespread, persistent, and inapparent contamination of the environment and fomites can make outbreaks extremely difficult to control. 147, 274, 283 these clinical observations and the detection of norovirus dna on horizontal surfaces 5 feet above the level that might be touched normally suggest that under certain circumstances, aerosolized particles may travel distances beyond 3 feet. 147 it is hypothesized that infectious particles may be aerosolized from vomitus, inhaled, and swallowed. in addition, individuals who are responsible for cleaning the environment may be at increased risk of infection. development of disease and transmission may be facilitated by the low infectious dose (ie, , 100 viral particles) 288 and the resistance of these viruses to the usual cleaning and disinfection agents (ie, they may survive , 10 ppm chlorine). [289] [290] [291] an alternate phenolic agent that was shown to be effective against feline calicivirus was used for environmental cleaning in one outbreak. 275, 292 there are insufficient data to determine the efficacy of alcohol-based hand rubs against noroviruses when the hands are not visibly soiled. 293 absence of disease in certain individuals during an outbreak may be explained by protection from infection conferred by the b histo-blood group antigen. 294 consultation on outbreaks of gastroenteritis is available through the cdc's division of viral and rickettsial diseases. 295 i.c.7. hemorrhagic fever viruses. hfv is a mixed group of viruses that cause serious disease with high fever, skin rash, bleeding diathesis, and, in some cases, high mortality; the resulting disease is referred to as viral hemorrhagic fever (vhf). among the more commonly known hfvs are ebola and marburg viruses (filoviridae), lassa virus (arenaviridae), crimean-congo hemorrhagic fever and rift valley fever virus (bunyaviridae), and dengue and yellow fever viruses (flaviviridae). 212, 296 these viruses are transmitted to humans through contact with infected animals or via arthropod vectors. although none of these viruses is endemic in the united states, outbreaks in affected countries provide potential opportunities for importation by infected humans and animals. furthermore, there is a concern that some of these agents could be used as bioweapons. 212 person-to-person transmission has been documented for ebola, marburg, lassa, and crimean-congo hfvs. in resource-limited health care settings, transmission of these agents to hcws, patients, and visitors has been described and in some outbreaks has accounted for a large proportion of cases. [297] [298] [299] transmission within households also has been documented in individuals who had direct contact with ill persons or their body fluids, but not in those who did not have such contact. 300 evidence concerning the transmission of hfvs has been summarized previously. 212, 301 person-to-person transmission is associated primarily with direct blood and body fluid contact. percutaneous exposure to contaminated blood carries a particularly high risk for transmission and increased mortality. 302, 303 the finding of large numbers of ebola viral particles in the skin and the lumina of sweat glands has raised concerns that transmission could occur from direct contact with intact skin, although epidemiologic evidence to support this is lacking. 304 postmortem handling of infected bodies is an important risk for transmission. 300, 305, 306 in rare situations, cases in which the mode of transmission was unexplained among individuals with no known direct contact have led to speculation that airborne transmission could have occurred. 297 however, airborne transmission of naturally occurring hfvs in humans has not been documented. a study of airplane passengers exposed to an in-flight index case of lassa fever found no transmission to any passengers. 307 in the laboratory setting, animals have been infected experimentally with marburg or ebola virus through direct inoculation of the nose, mouth, and/or conjunctiva 308,309 and by using mechanically generated viruscontaining aerosols. 310, 311 transmission of ebola virus among laboratory primates in an animal facility has been described. 312 the secondarily infected animals were in individual cages separated by approximately 3 meters. although the possibility of airborne transmission was suggested, the investigators were not able to exclude droplet or indirect contact transmission in this incidental observation. guidance on infection control precautions for hvfs transmitted person-to-person have been published by the cdc 1,211 and by the johns hopkins center for civilian biodefense strategies. 212 the most recent recommendations at the time of publication of this document were posted on the cdc website on may 19, 2005. 313 inconsistencies among the various recommendations have raised questions about the appropriate precautions to use in us hospitals. in less developed countries, outbreaks of hfvs have been controlled with basic hygiene, barrier precautions, safe injection practices, and safe burial practices. 298, 305 the preponderance of evidence on hfv transmission indicates that standard, contact, and droplet precautions with eye protection are effective in protecting hcws and visitors coming in contact with an infected patient. single gloves are adequate for routine patient care; doublegloving is advised during invasive procedures (eg, surgery) that pose an increased risk of blood exposure. routine eye protection (ie goggles or face shield) is particularly important. fluid-resistant gowns should be worn for all patient contact. airborne precautions are not required for routine patient care; however, use of aiirs is prudent when procedures that could generate infectious aerosols are performed (eg, endotracheal intubation, bronchoscopy, suctioning, autopsy procedures involving oscillating saws). n95 or higher-level respirators may provide added protection for individuals in a room during aerosol-generating procedures ( table 3 , appendix a). when a patient with a syndrome consistent with hemorrhagic fever also has a history of travel to an endemic area, precautions are initiated on presentation and then modified as more information is obtained ( table 2) . patients with hemorrhagic fever syndrome in the setting of a suspected bioweapons attack should be managed using airborne precautions, including aiirs, because the epidemiology of a potentially weaponized hemorrhagic fever virus is unpredictable. numerous factors influence differences in transmission risks among the various health care settings. these factors include the population characteristics (eg, increased susceptibility to infections, type and prevalence of indwelling devices), intensity of care, exposure to environmental sources, length of stay, and frequency of interaction between patients/residents with each other and with hcws. these factors, as well as organizational priorities, goals, and resources, influence how different health care settings adapt transmission prevention guidelines to meet their specific needs. 314, 315 infection control management decisions are informed by data regarding institutional experience/epidemiology; trends in community and institutional hais; local, regional, and national epidemiology; and emerging infectious disease threats. i.d.1. hospitals. infection transmission risks are present in all hospital settings. however, certain hospital settings and patient populations have unique conditions that predispose patients to infection and merit special mention. these are often sentinel sites for the emergence of new transmission risks that may be unique to that setting or present opportunities for transmission to other settings in the hospital. i.d.1.a. intensive care units. intensive care units (icus) serve patients who are immunocompromised by disease state and/or by treatment modalities, as well as patients with major trauma, respiratory failure, and other life-threatening conditions (eg, myocardial infarction, congestive heart failure, overdose, stroke, gastrointestinal bleeding, renal failure, hepatic failure, multiorgan system failure, and extremes of age). although icus account for a relatively small proportion of hospitalized patients, infections acquired in these units account for . 20% of all hais. 316 in the national nosocomial infection surveillance (nnis) system, 26.6% of hais were reported from icu and high-risk nursery (neonatal icu [nicu]) patients in 2002 (nnis, unpublished data). this patient population has increased susceptibility to colonization and infection, especially with mdros and candida spp, 317,318 because of underlying diseases and conditions, the invasive medical devices and technology used in their care (eg central venous catheters and other intravascular devices, mechanical ventilators, extracorporeal membrane oxygenation, hemodialysis/filtration, pacemakers, implantable left-ventricular assist devices), the frequency of contact with hcws, prolonged lengths of stay, and prolonged exposure to antimicrobial agents. [319] [320] [321] [322] [323] [324] [325] [326] [327] [328] [329] [330] furthermore, adverse patient outcomes in this setting are more severe and are associated with a higher mortality. 331 outbreaks associated with various bacterial, fungal, and viral pathogens due to common-source and person-to-person transmissions are frequent in adult icus and pediatric icus (picus). 31, [332] [333] [334] [335] [336] [337] i.d.1.b. burn units. burn wounds can provide optimal conditions for colonization, infection, and transmission of pathogens; infection acquired by burn patients is a frequent cause of morbidity and mortality. 319, 338, 339 the risk of invasive burn wound infection is particularly high in patients with a burn injury involving . 30% of the total body surface area (tbsa). 340, 341 infections occurring in patients with burn injuries involving , 30% of the tbsa are usually associated with the use of invasive devices. mssa, mrsa, enterococci (including vre), gram-negative bacteria, and candida spp are prevalent pathogens in burn infections, 53, 339, [342] [343] [344] [345] [346] [347] [348] [349] and outbreaks of these organisms have been reported. [350] [351] [352] [353] shifts over time in the predominance of pathogens causing infections in burn patients often lead to changes in burn care practices. 342, [354] [355] [356] [357] burn wound infections caused by aspergillus spp or other environmental molds may result from exposure to supplies contaminated during construction 358 or to dust generated during construction or other environmental disruption. 359 hydrotherapy equipment is an important environmental reservoir of gram-negative organisms. its use in burn care is discouraged based on demonstrated associations between the use of contaminated hydrotherapy equipment and infections. burn wound infections and colonization, as well as bloodstream infections, caused by multidrug-resistant p aeruginosa, 360 acinetobacter baumannii, 361 and mrsa 351 have been associated with hydrotherapy; thus, excision of burn wounds in operating rooms is the preferred approach. advances in burn care (specifically, early excision and grafting of the burn wound, use of topical antimicrobial agents, and institution of early enteral feeding) have led to decreased infectious complications. other advances have included prophylactic antimicrobial use, selective digestive decontamination, and use of antimicrobial-coated catheters; however, few epidemiologic studies and no efficacy studies have been performed to investigate the relative benefit of these measures. 356 there is no consensus on the most effective infection control practices to prevent transmission of infections to and from patients with serious burns (eg, single-bed rooms, 357 laminar flow, 362 and high-efficiency particulate air [hepa] filtration, 359 or maintaining burn patients in a separate unit with no exposure to patients or equipment from other units 363 ). there also is controversy regarding the need for and type of barrier precautions in the routine care of burn patients. one retrospective study demonstrated the efficacy and cost-effectiveness of a simplified barrier isolation protocol for wound colonization, emphasizing handwashing and use of gloves, caps, masks, and impermeable plastic aprons (rather than isolation gowns) for direct patient contact. 364 however, to date no studies have determined the most effective combination of infection control precautions for use in burn settings. prospective studies in this area are needed. i.d.1.c. pediatrics. studies of the epidemiology of hais in children have identified unique infection control issues in this population. 63, 64, [365] [366] [367] [368] [369] pediatric icu patients and the lowest birth weight babies in the nicu monitored in the nnis system have had high rates of central venous catheter-associated bloodstream infections. 64 38, 377 ) . close physical contact between hcws and infants and young children (eg. cuddling, feeding, playing, changing soiled diapers, and cleaning copious uncontrolled respiratory secretions) provides abundant opportunities for transmission of infectious material. such practices and behaviors as congregation of children in play areas where toys and bodily secretions are easily shared and rooming-in of family members with pediatric patients can further increase the risk of transmission. pathogenic bacteria have been recovered from toys used by hospitalized patients; 378 contaminated bath toys were implicated in an outbreak of multidrug-resistant p. aeruginosa on a pediatric oncology unit. 80 in addition, several patient factors increase the likelihood that infection will result from exposure to pathogens in health care settings (eg, immaturity of the neonatal immune system, lack of previous natural infection and resulting immunity, prevalence of patients with congenital or acquired immune deficiencies, congenital anatomic anomalies, and use of life-saving invasive devices in nicus and picus). 63 there are theoretical concerns that infection risk will increase in association with innovative practices used in the nicu for the purpose of improving developmental outcomes, such factors include cobedding 379 and kangaroo care, 380 which may increase opportunity for skin-to-skin exposure of multiple gestation infants to each other and to their mothers, respectively; although the risk of infection actually may be reduced among infants receiving kangaroo care. 381 children who attend child care centers 382, 383 and pediatric rehabilitation units 384 may increase the overall burden of antimicrobial resistance by contributing to the reservoir of ca-mrsa. [385] [386] [387] [388] [389] [390] patients in chronic care facilities may have increased rates of colonization with resistant garm-negative bacilli and may be sources of introduction of resistant organisms to acute care settings. 50 i.d.2. nonacute health care settings. health care is provided in various settings outside of hospitals, including long-term care facilities (ltcfs) (eg nursing homes), homes for the developmentally disabled, behavioral health service settings, rehabilitation centers, and hospices. 391 in addition, health care may be provided in non-health care settings, such as workplaces with occupational health clinics, adult day care centers, assisted-living facilities, homeless shelters, jails and prisons, school clinics, and infirmaries. each of these settings has unique circumstances and population risks that must be considered when designing and implementing an infection control program. several of the most common settings and their particular challenges are discussed below. although this guideline does not address each setting, the principles and strategies provided herein may be adapted and applied as appropriate. i.d.2.a. long-term care. the designation ltcf applies to a diverse group of residential settings, ranging from institutions for the developmentally disabled to nursing homes for the elderly and pediatric chronic care facilities. [392] [393] [394] nursing homes for the elderly predominate numerically and frequently represent longterm care as a group of facilities. approximately 1.8 million americans reside in the nation's 16,500 nursing homes. 395 estimates of hai rates of 1.8 to 13.5 per 1000 resident-care days have been reported, with a range of 3 to 7 per 1000 resident-care days in the more rigorous studies. [396] [397] [398] [399] [400] the infrastructure described in the department of veterans affairs' nursing home care units is a promising example for the development of a nationwide hai surveillance system for ltcfs. 401 lctfs are different from other health care settings in that elderly patients at increased risk for infection are brought together in one setting and remain in the facility for extended periods; for most residents, it is their home. an atmosphere of community is fostered, and residents share common eating and living areas and participate in various facility-sponsored activities. 402, 403 because able residents interact freely with each other, controlling infection transmission in this setting can be challenging. 404 a residents who is colonized or infected with certain microorganisms are in some cases restricted to his or her room. however, because of the psychosocial risks associated with such restriction, balancing psychosocial needs with infection control needs is important in the ltcf setting. 405 274, 277, 278, 280 ) and bacteria, including group a streptococcus, 162 , b pertussis, 414 nonsusceptible s pneumoniae, 197, 198 other mdros, and c difficile 415 ). these pathogens can lead to substantial morbidity and mortality, as well as increased medical costs; prompt detection and implementation of effective control measures are needed. risk factors for infection are prevalent among ltcf residents. 394, 416, 417 age-related declines in immunity may affect the response to immunizations for influenza and other infectious agents and increase the susceptibility to tuberculosis. immobility, incontinence, dysphagia, underlying chronic diseases, poor functional status, and age-related skin changes increase susceptibility to urinary, respiratory, and cutaneous and soft tissue infections, whereas malnutrition can impair wound healing. [418] [419] [420] [421] [422] medications (eg, drugs that affect level of consciousness, immune function, gastric acid secretions, and normal flora, including antimicrobial therapy) and invasive devices (eg, urinary catheters and feeding tubes) heighten the susceptibility to infection and colonization in ltcf residents. [423] [424] [425] finally, limited functional status and total dependence on hcws for activities of daily living have been identified as independent risk factors for infection 400, 416, 426 and for colonization with mrsa 427,428 and esbl-producing klebsiella pneumoniae. 429 several position papers and review articles provide guidance on various aspects of infection control and antimicrobial resistance in ltcfs. [405] [406] [407] [430] [431] [432] [433] [434] [435] the centers for medicare and medicaid services has established regulations for the prevention of infection in ltcfs. 436 because residents of ltcfs are hospitalized frequently, they can transfer pathogens between ltcfs and health care facilities in which they receive care. 8, [437] [438] [439] [440] this also is true for pediatric long-term care populations. pediatric chronic care facilities have been associated with the importation of extendedspectrum cephalosporin-resistant, gram-negative bacilli into a picu. 50 children from pediatric rehabilitation units may contribute to the reservoir of community-associated mrsa. 384, [388] [389] [390] i.d.2.b. ambulatory care. over the past decade, health care delivery in the united states has shifted from the acute, inpatient hospital to various ambulatory and community-based settings, including the home. ambulatory care is provided in hospital-based outpatient clinics, nonhospital-based clinics and physicians' offices, public health clinics, free-standing dialysis centers, ambulatory surgical centers, urgent care centers, and other setting. in 2000, there were 83 million visits to hospital outpatient clinics and more than 823 million visits to physicians' offices; 441 ambulatory care now accounts for most patient encounters with the health care system. 442 adapting transmission prevention guidelines to these settings is challenging, because patients remain in common areas for prolonged periods waiting to be seen by a health care provider or awaiting admission to the hospital, examination or treatment rooms are turned around quickly with limited cleaning, and infectious patients may not be recognized immediately. furthermore, immunocompromised patients often receive chemotherapy in infusion rooms, where they stay for extended periods along with other types of patients. little data exist on the risk of hais in ambulatory care settings, with the exception of hemodialysis centers. 18, 443, 444 transmission of infections in outpatient settings has been reviewed in 3 studies. [445] [446] [447] goodman and solomon 445 summarized 53 clusters of infections associated with the outpatient setting between 1961 and 1990. overall, 29 clusters were associated with common source transmission from contaminated solutions or equipment, 14 were associated with person-to-person transmission from or involving hcws, and 10 were associated with airborne or droplet transmission among patients and health care workers. transmission of bloodborne pathogens (ie, hbv, hcv, and, rarely, hiv) in outbreaks, sometimes involving hundreds of patients, continues to occur in ambulatory settings. these outbreaks often are related to common source exposures, usually a contaminated medical device, multidose vial, or intravenous solution. 82, [448] [449] [450] [451] [452] in all cases, transmission has been attributed to failure to adhere to fundamental infection control principles, including safe injection practices and aseptic technique. this subject has been reviewed, and recommended infection control and safe injection practices have been summarized. 453 airborne transmission of m tuberculosis and measles in ambulatory settings, most often emergency departments, has been reported. 34, 127, 445, 447, [454] [455] [456] measles virus was transmitted in physicians' offices and other outpatient settings during an era when immunization rates were low and measles outbreaks in the community were occurring regularly. 34, 122, 457 rubella has been transmitted in the outpatient obstetric setting; 33 there are no published reports of varicella transmission in the outpatient setting. in the ophthalmology setting, adenovirus type 8 epidemic keratoconjunctivitis has been transmitted through incompletely disinfected ophthalmology equipment and/or from hcws to patients, presumably by contaminated hands. 17, 445, 447, [458] [459] [460] [461] preventing transmission in outpatient settings necessitates screening for potentially infectious symptomatic and asymptomatic individuals, especially those at possible risk for transmitting airborne infectious agents (eg, m tuberculosis, varicella-zoster virus, rubeola [measles]), at the start of the initial patient encounter. on identification of a potentially infectious patient, implementation of prevention measures, including prompt separation of potentially infectious patients and implementation of appropriate control measures (eg, respiratory hygiene/cough etiquette and transmission-based precautions) can decrease transmission risks. 9, 12 transmission of mrsa and vre in outpatient settings has not been reported, but the association of ca-mrsa in hcws working in an outpatient hiv clinic with environmental ca-mrsa contamination in that clinic suggests the possibility of transmission in that setting. 462 patient-to-patient transmission of burkholderia spp and p aeruginosa in outpatient clinics for adults and children with cystic fibrosis has been confirmed. 463, 464 i.d.2.c. home care. home care in the united states is delivered by more than 20,000 provider agencies, including home health agencies, hospices, durable medical equipment providers, home infusion therapy services, and personal care and support services providers. home care is provided to patients of all ages with both acute and chronic conditions. the scope of services ranges from assistance with activities of daily living and physical and occupational therapy to the care of wounds, infusion therapy, and chronic ambulatory peritoneal dialysis. the incidence of infection in home care patients, other than that associated with infusion therapy, has not been well studied. [465] [466] [467] [468] [469] [470] however, data collection and calculation of infection rates have been done for central venous catheter-associated bloodstream infections in patients receiving home infusion therapy [469] [470] [471] [472] [473] and for the risk of blood contact through percutaneous or mucosal exposures, demonstrating that surveillance can be performed in this setting. 474 draft definitions for home care-associated infections have been developed. 475 transmission risks during home care are presumed to be minimal. the main transmission risks to home care patients are from an infectious home care provider or contaminated equipment; a provider also can be exposed to an infectious patient during home visits. because home care involves patient care by a limited number of personnel in settings without multiple patients or shared equipment, the potential reservoir of pathogens is reduced. infections of home care providers that could pose a risk to home care patients include infections transmitted by the airborne or droplet routes (eg, chickenpox, tuberculosis, influenza), skin infestations (eg, scabies 69 and lice), and infections transmitted by direct or indirect contact (eg, impetigo). there are no published data on indirect transmission of mdros from one home care patient to another, although this is theoretically possible if contaminated equipment is transported from an infected or colonized patient and used on another patient. of note, investigations of the first case of visa in home care 186 and the first 2 reported cases of vrsa 178, 180, 181, 183 found no evidence of transmission of visa or vrsa to other home care recipients. home health care also may contribute to antimicrobial resistance; a review of outpatient vancomycin use found that 39% of recipients did not receive prescribed antibiotics according to recommended guidelines. 476 although most home care agencies implement policies and procedures aimed at preventing transmission of organisms, the current approach is based on the adaptation of the 1996 guideline for isolation precautions in hospitals, 1 as well as other professional guidance. 477, 478 this issue has proven very challenging to the home care industry, and practice has been inconsistent and frequently not evidence-based. for example, many home health agencies continue to observe ''nursing bag technique,'' a practice that prescribes the use of barriers between the nursing bag and environmental surfaces in the home. 479 although the home environment may not always appear clean, the use of barriers between 2 noncritical surfaces has been questioned. 480, 481 opportunites exist to conduct research in home care related to infection transmission risks. 482 i.d.2.d. other sites of health care delivery. facilities that are not primarily health care settings but in which health care is delivered include clinics in correctional facilities and shelters. both of these settings can have suboptimal features, such as crowded conditions and poor ventilation. economically disadvantaged individuals who may have chronic illnesses and health care problems related to alcoholism, injected drug use, poor nutrition, and/or inadequate shelter often receive their primary health care at such sites. 483 infectious diseases of special concern for transmission include tuberculosis, scabies, respiratory infections (eg, n meningitides, s pneumoniae), sexually transmitted and bloodborne diseases (eg, hiv, hbv, hcv, syphilis, gonorrhea), hepatitis a virus, diarrheal agents such as norovirus, and foodborne diseases. 285, [484] [485] [486] [487] a high index of suspicion for tuberculosis and ca-mrsa in these populations is needed; outbreaks in these settings or among the populations they serve have been reported. [488] [489] [490] [491] [492] [493] [494] [495] [496] patient encounters in these types of facilities provide an opportunity to deliver recommended immunizations and screen for m tuberculosis infection, along with diagnosing and treating acute illnesses. 497 recommended infection control measures in these nontraditional areas designated for health care delivery are the same as for other ambulatory care settings. therefore, these settings must be equipped to observe standard precautions and, when indicated, transmission-based precautions. as new treatments emerge for complex diseases, unique infection control challenges associated with special patient populations must be addressed. i.e.1. immunocompromised patients. patients who have congenital primary immune deficiencies or acquired disease (eg. treatment-induced immune deficiencies) are at increased risk for numerous types of infections while receiving health care; these patients may be located throughout the health care facility. the specific immune system defects determine the types of infections most likely to be acquired (eg, viral infections are associated with t cell defects, and fungal and bacterial infections occur in patients who are neutropenic). as a general group, immunocompromised patients can be cared for in the same environment as other patients; however, it is always advisable to minimize exposure to other patients with transmissible infections, such as influenza and other respiratory viruses. 498, 499 the use of more intense chemotherapy regimens for treatment of childhood leukemia may be associated with prolonged periods of neutropenia and suppression of other components of the immune system, extending the period of infection risk and raising the concern that additional precautions may be indicated for select groups. 500, 501 with the application of newer and more intense immunosuppressive therapies for various medical conditions (eg, rheumatologic disease, 502, 503 inflammatory bowel disease 504 ), immunosuppressed patients are likely to be more widely distributed throughout a health care facility rather than localized to single patient units (eg, hematologyoncology). guidelines for preventing infections in certain groups of immunocompromised patients have been published previously. 15, 505, 506 published data provide evidence to support placing patients undergoing allogeneic hsct in a pe. 15, 157, 158 in addition, guidelines have been developed that address the special requirements of these immunocompromised patients, including use of antimicrobial prophylaxis and engineering controls to create a pe for the prevention of infections caused by aspergillus spp and other environmental fungi. 11, 14, 15 as more intense chemotherapy regimens associated with prolonged periods of neutropenia or graft-versus-host disease are implemented, the period of risk and duration of environmental protection may need to be prolonged beyond the traditional 100 days. 507 i.e.2. cystic fibrosis patients. patients with cystic fibrosis (cf) require special consideration when developing infection control guidelines. compared with other patients, cf patients require additional protection to prevent transmission from contaminated respiratory therapy equipment. [508] [509] [510] [511] [512] such infectious agents as b cepacia complex and p aeruginosa. 463, 464, 513, 514 have unique clinical and prognostic significance. in cf patients, b cepacia infection has been associated with increased morbidity and mortality, [515] [516] [517] whereas delayed acquisition of chronic p aeruginosa infection may be associated with an improved long-term clinical outcome. 518, 519 person-to-person transmission of b cepacia complex has been demonstrated among children 516 and adults 520 with cf in health care settings 463, 521 and from various social contacts, 522 most notably attendance at camps for patients with cf 523 and among siblings with cf. 524 successful infection control measures used to prevent transmission of respiratory secretions include segregation of cf patients from each other in ambulatory and hospital settings (including use of private rooms with separate showers), environmental decontamination of surfaces and equipment contaminated with respiratory secretions, elimination of group chest physiotherapy sessions, and disbanding of cf camps. 97, 525 the cystic fibrosis foundation has published a consensus document with evidence-based recommendations for infection control practices in cf patients. 20 i.f. new therapies associated with potentially transmissible infectious agents i.f.1. gene therapy. gene therapy has has been attempted using various viral vectors, including nonreplicating retroviruses, adenoviruses, adeno-associated viruses, and replication-competent strains of poxviruses. unexpected adverse events have restricted the prevalence of gene therapy protocols. the infectious hazards of gene therapy are theoretical at this time but require meticulous surveillance due to the possible occurrence of in vivo recombination and the subsequent emergence of a transmissible genetically altered pathogen. the greatest concern attends the use of replication-competent viruses, especially vaccinia. to date, no reports have described transmission of a vector virus from a gene therapy recipient to another individual, but surveillance is ongoing. recommendations for monitoring infection control issues throughout the course of gene therapy trials have been published. [526] [527] [528] i.f.2. infections transmitted through blood, organs, and other tissues. the potential hazard of transmitting infectious pathogens through biologic products is a small but ever-present risk, despite donor screening. reported infections transmitted by transfusion or transplantation include west nile virus infection, 529 cytomegalovirus infection, 530 cjd, 230 hepatitis c, 531 infections with clostridium spp 532 and group a streptococcus, 533 malaria, 534 babesiosis, 535 chagas disease, 536 lymphocytic choriomeningitis, 537 and rabies. 538, 539 therefore, it is important to consider receipt of biologic products when evaluating patients for potential sources of infection. i.f.3. xenotransplantation. transplantation of nonhuman cells, tissues, and organs into humans potentially exposes patients to zoonotic pathogens. transmission of known zoonotic infections (eg, trichinosis from porcine tissue) is of concern. also of concern is the possibility that transplantation of nonhuman cells, tissues, or organs may transmit previously unknown zoonotic infections (xenozoonoses) to immunosuppressed human recipients. potential infections that potentially could accompany transplantation of porcine organs have been described previously. 540 guidelines from the us public health service address many infectious diseases and infection control issues that surround the developing field of xenotransplantation; 541 549 policies and procedures that explain how standard precautions and transmission-based precautions are applied, including systems used to identify and communicate information on patients with potentially transmissible infectious agents, are essential to ensure the success of these measures. these policies and procedures may vary according to the characteristics of the organization. a key administrative measure is the provision of fiscal and human resources for maintaining infection control and occupational health programs that are responsive to emerging needs. specific components include bedside nurse 550 and infection prevention and control professional (icp) staffing levels, 551 inclusion of icps in facility construction and design decisions, 11 clinical microbiology laboratory support, 552, 553 adequate supplies and equipment including facility ventilation systems, 11 adherence monitoring, 554 assessment and correction of system failures that contribute to transmission, 555, 556 and provision of feedback to hcws and senior administrators. 433, 547, 548, 557 the positive influence of institutional leadership has been demonstrated repeatedly in studies of hcws' adherence to recommended hand hygiene practices. 176, 177, 433, 547, 548, [558] [559] [560] [561] [562] [563] health care administrators' involvement in the infection control processes can improve their awareness of the rationale and resource requirements for following recommended infection control practices. several administrative factors may affect the transmission of infectious agents in health care settings, including the institutional culture, individual hcw behavior, and the work environment. each of these areas is suitable for performance improvement monitoring and incorporation into the organization's patient safety goals. 542, 543, 545, 564 ii.a.1.a. scope of work and staffing needs for infection control professionals. the effectiveness of infection surveillance and control programs in preventing nosocomial infections in ust hospitals was assessed by the cdc through the study on the efficacy of nosocomial infection control (senic project) conducted between 1970 and 1976. 565 in a representative sample of us general hospitals, those with a trained infection control physician or microbiologist involved in an infection control program and at least 1 infection control nurse per 250 beds were associated with a 32% lower rate of the 4 infections studied (cvc-associated bloodstream infections, ventilator-associated pneumonias, catheter-related urinary tract infections, and surgical site infections). since the publication of that landmark study, responsibilities of icps have expanded commensurate with the growing complexity of the health care system, the patient populations served, and the increasing numbers of medical procedures and devices used in all types of health care settings. the scope of work of icps was first assessed in 1982 566-568 by the certification board of infection control, and has been reassessed every 5 years since that time. 557, [569] [570] [571] the findings of these analyses have been used to develop and update the infection control certification examination, which was first offered in 1983. with each new survey, it becomes increasingly apparent that the role of the icp is growing in complexity and scope beyond traditional infection control activities in acute care hospitals. activities currently assigned to icps in response to emerging challenges include (1) surveillance and infection prevention at facilities other than acute care hospitals (eg, ambulatory clinics, day surgery centers, ltcfs, rehabilitation centers, home care); (2) oversight of employee health services related to infection prevention (eg, assessment of risk and administration of recommended treatment after exposure to infectious agents, tuberculosis screening, influenza vaccination, respiratory protection fit testing, and administration of other vaccines as indicated, such as smallpox vaccine in 2003); (3) preparedness planning for annual influenza outbreaks, pandemic influenza, sars, and bioweapons attacks; (4) adherence monitoring for selected infection control practices; (5) oversight of risk assessment and implementation of prevention measures associated with construction and renovation; (6) prevention of transmission of mdros; (7) evaluation of new medical products that could be associated with increased infection risk (eg, intravenous infusion materials); (8) communication with the public, facility staff, and state and local health departments concerning infection control-related issues; and (9) participation in local and multicenter research projects. 433, 548, 551, 557, 572, 573 none of the certification board of infection control job analyses addressed specific staffing requirements for the identified tasks, although the surveys did include information about hours worked; the 2001 survey included the number of icps assigned to the responding facilities. 557 there is agreement in the literature that a ratio of 1 icp per 250 acute care beds is no longer adequate to meet current infection control needs; a delphi project that assessed staffing needs of infection control programs in the 21 st century concluded that a ratio of 0.8 to 1.0 icp per 100 occupied acute care beds is an appropriate staffing level. 551 a survey of participants in the nnis system found an average daily patient census of 115 per icp. 315 results of other studies have been similar: 3 per 500 beds for large acute care hospitals, 1 per 150 to 250 beds in ltcfs, and 1.56 per 250 in small rural hospitals. 572, 574 the foregoing demonstrates that infection control staffing no longer can be based on patient census alone, but rather must be determined by the scope of the program, characteristics of the patient population, complexity of the health care system, tools available to assist personnel to perform essential tasks (eg, electronic tracking and laboratory support for surveillance), and unique or urgent needs of the institution and community. 551 furthermore, appropriate training is required to optimize the quality of work performed. 557, 571, 575 ii.a.1.a.i. infection control nurse liaison. designating a bedside nurse on a patient care unit as an infection control liaison or ''link nurse'' is reported to be an effective adjunct to enhance infection control at the unit level. [576] [577] [578] [579] [580] [581] such individuals receive training in basic infection control and have frequent communication with icps, but maintain their primary role as bedside caregiver on their units. the infection control nurse liaison increases the awareness of infection control at the unit level. he or she is especially effective in implementating new policies or control interventions because of the rapport with individuals on the unit, an understanding of unit-specific challenges, and ability to promote strategies that are most likely to be successful in that unit. this position is an adjunct to, not a replacement for, fully trained icps. furthermore, the infection control liaison nurses should not be counted when considering icp staffing. there is increasing evidence that the level of bedside nurse staffing influences the quality of patient care. 582, 583 adequate nursing staff makes it more likely that infection control practices, including hand hygiene, standard precautions, and transmission-based precautions, will be given appropriate attention and applied correctly and consistently. 551 a national multicenter study reported strong and consistent inverse relationships between nurse staffing and 5 adverse outcomes in medical patients, 2 of which were hais (urinary tract infections and pneumonia). 582 the association of nursing staff shortages with increased rates of hai has been demonstrated in several outbreaks in hospitals and ltcfs, and with increased transmission of hepatitis c virus in dialysis units. 22, 417, 550, [584] [585] [586] [587] [588] [589] [590] [591] [592] [593] [594] [595] [596] in most cases, when staffing was improved as part of a comprehensive control intervention, the outbreak ended or the hai rate declined. in 2 studies, 589,595 the composition of the nursing staff (''pool'' or ''float'' vs regular staff nurses) influenced the rate of primary bloodstream infections, with an increased infection rate occurring when the proportion of regular nurses decreased and that of pool nurses increased. ii.a.1.c. clinical microbiology laboratory support. the critical role of the clinical microbiology laboratory in infection control and health care epidemiology has been well described 552, 553, [597] [598] [599] and is supported by the infectious disease society of america's policy statement on the consolidation of clinical microbiology laboratories published in 2001. 552 the clinical microbiology laboratory contributes to preventing transmission of infectious diseases in health care settings by promptly detecting and reporting epidemiologically important organisms, identifying emerging patterns of antimicrobial resistance, and assessing the effectiveness of recommended precautions to limit transmission during outbreaks. 597 outbreaks of infections may be recognized first by laboratorians. 161 health care organizations need to ensure the availability of the recommended scope and quality of laboratory services, a sufficient number of appropriately trained laboratory staff members, and systems to promptly communicate epidemiologically important results to those who will take action (eg, providers of clinical care, infection control staff, health care epidemiologists, and infectious disease consultants). 600 as concerns about emerging pathogens and bioterrorism grow, the role of the clinical microbiology laboratory assumes ever-greater importance. for health care organizations that outsource microbiology laboratory services (eg, ambulatory care, home care, ltcfs, smaller acute care hospitals), it is important to specify by contract the types of services (eg, periodic institution-specific aggregate susceptibility reports) required to support infection control. several key functions of the clinical microbiology laboratory are relevant to this guideline: ii.a.2. institutional safety culture and organizational characteristics. safety culture (or safety climate) refers to a work environment in which a shared commitment to safety on the part of management and the workforce is understood and maintained. 558, 619, 620 the authors of the institute of medicine's report titled to err is human 542 acknowledged that causes of medical error are multifaceted but emphasized the pivotal role of system failures and the benefits of a safety culture. a safety culture is created through (1) the actions that management takes to improve patient and worker safety, (2) worker participation in safety planning, (3) the availability of appropriate ppe, (4) the influence of group norms regarding acceptable safety practices, and (5) the organization's socialization process for new personnel. safety and patient outcomes can be enhanced by improving or creating organizational characteristics within patient care units, as demonstrated by studies of surgical icus. 621, 622 each of these factors has a direct bearing on adherence to transmission prevention recommendations. 256 measurement of an institution's culture of safety is useful in designing improvements in health care. 623, 624 several hospitalbased studies have linked measures of safety culture with both employee adherence to safe practices and reduced exposures to blood and body fluids. [625] [626] [627] [628] [629] [630] [631] one study of hand hygiene practices concluded that improved adherence requires integration of infection control into the organization's safety culture. 560 several hospitals that are part of the veterans administration health care system have taken specific steps toward improving the safety culture, including error-reporting mechanisms, root cause analyses of identified problems, safety incentives, and employee education. [632] [633] [634] ii.a.3. adherence of health care workers to recommended guidelines. hcws' adherence to recommended infection control practices decreases the transmission of infectious agents in health care settings. 116, 561, [635] [636] [637] [638] [639] several observational studies have shown limited adherence to recommended practices by hcws. 558, [639] [640] [641] [642] [643] [644] [645] [646] [647] [648] [649] [650] [651] [652] [653] [654] [655] [656] observed adherence to universal precautions ranged from 43% to 89%. 640, 641, 648, 650, 651 the degree of adherence often depended on the specific practice that was assessed and, for glove use, the circumstance in which the practice was applied. observed rates of appropriate glove use has ranged from a low of 15% 644 to a high of 82%. 649 however, 92% and 98% adherence with glove use have been reported during arterial blood gas collection and resuscitation, respectively, procedures in which considerable blood contact may occur. 642, 655 differences in observed adherence have been reported among occupational groups in the same health care facility 640 and between experienced and nonexperienced professionals. 644 in surveys of hcws, self-reported adherence was generally higher than actual adherence found in observational studies. furthermore, where an observational component was included with a self-reported survey, self-perceived adherence was often greater than observed adherence. 656 among nurses and physicians, increasing years of experience is a negative predictor of adherence. 644, 650 education to improve adherence is the primary intervention that has been studied. whereas positive changes in knowledge and attitude have been demonstrated, 639, 657 no or only limited accompanying changes in behavior often have been found. 641, 643 self-reported adherence is higher in groups that received an educational intervention. 629, 658 in one study, educational interventions that incorporated videotaping and performance feedback were successful in improving adherence during the study period, but the long-term effect of such interventions is not known. 653 the use of videotaping also served to identify system problems (eg, communication and access to ppe) that otherwise may not have been recognized. interest is growing in the use of engineering controls and facility design concepts for improving adherence. whereas the introduction of automated sinks was found to have a negative impact on consistent adherence to handwashing in one study, 659 the use of electronic monitoring and voice prompts to remind hcws to perform hand hygiene and improving accessibility to hand hygiene products increased adherence and contributed to a decrease in hais in another study. 660 more information is needed regarding ways in which technology might improve adherence. improving adherence to infection control practices requires a multifaceted approach that incorporates continuous assessment of both the individual and the work environment. 558, 560 using several behavioral theories, kretzer and larson concluded that a single intervention (eg, a handwashing campaign or putting up new posters about transmission precautions) likely would be ineffective in improving hcws adherence. 661 improvement requires the organizational leadership to make prevention an institutional priority and integrate infection control practices into the organization's safety culture. 560 a recent review of the literature concluded that variations in organizational factors (eg, safety climate, policies and procedures, education and training) and individual factors (eg, knowledge, perceptions of risk, past experience) were determinants of adherence to infection control guidelines for protection against sars and other respiratory pathogens. 256 surveillance is an essential tool for case finding of single patients or clusters of patients who are infected or colonized with epidemiologically important organisms (eg, susceptible bacteria such as s aureus, s pyogenes [group a streptococcus] or enterobacter-klebsiella spp; mrsa, vre, and other mdros; c difficile; rsv; influenza virus) for which transmission-based precautions may be required. surveillance is defined as the ongoing systematic collection, analysis, interpretation, and dissemination of data regarding a health-related event for use in public health action to reduce morbidity and mortality and to improve health. 662 the work of ignaz semmelweis delineating the role of person-toperson transmission in puerperal sepsis is the earliest example of the use of surveillance data to reduce transmission of infectious agents. 663 surveillance of both process measures and the infection rates to which they are linked is important in evaluating the effectiveness of infection prevention efforts and identifying indications for change. 554, [664] [665] [666] [667] the study on the efficacy of nosocomial infection control (senic) found that different combinations of infection control practices resulted in reduced rates of nosocomial surgical site infections, pneumonia, urinary tract infections, and bacteremia in acute care hospitals; 565 however, surveillance was the only component essential for reducing all 4 types of hais. although a similar study has not been conducted in other health care settings, a role for surveillance and the need for novel strategies in ltcfs 397, 433, 668, 669 and in home care [469] [470] [471] [472] have been described. the essential elements of a surveillance system are (1) standardized definitions, (2) identification of patient populations at risk for infection, (3) statistical analysis (eg, risk adjustment, calculation of rates using appropriate denominators, trend analysis using such methods as statistical process control charts), and (4) feedback of results to the primary caregivers. [670] [671] [672] [673] [674] [675] data gathered through surveillance of high-risk populations, device use, procedures, and facility locations (eg, icus) are useful in detecting transmission trends. [670] [671] [672] identification of clusters of infections should be followed by a systematic epidemiologic investigation to determine commonalities in persons, places, and time and to guide implementation of interventions and evaluation of the effectiveness of those interventions. targeted surveillance based on the highest-risk areas or patients has been preferred over facility-wide surveillance for the most effective use of resources. 672, 675 however, for certain epidemiologically important organisms, surveillance may need to be facility-wide. surveillance methods will continue to evolve as health care delivery systems change 391, 676 and user-friendly electronic tools for electronic tracking and trend analysis become more widely available. 673, 677, 678 individuals with experience in health care epidemiology and infection control should be involved in selecting software packages for data aggregation and analysis, to ensure that the need for efficient and accurate hai surveillance will be met. effective surveillance is increasingly important as legislation requiring public reporting of hai rates is passed and states work to develop effective systems to support such legislation. 679 the education and training of hcws is a prerequisite for ensuring that policies and procedures for standard and transmission-based precautions are understood and practiced. understanding the scientific rationale for the precautions will allow hcws to apply procedures correctly, as well as to safely modify precautions based on changing requirements, resources, or health care settings. 14,654,680-687 one study found that the likelihood of hcws developing sars was strongly associated with less than 2 hours of infection control training and poor understanding of infection control procedures. 688 education regarding the important role of vaccines (eg, influenza, measles, varicella, pertussis, pneumococcal) in protecting hcws, their patients, and family members can help improve vaccination rates. [689] [690] [691] [692] education on the principles and practices for preventing transmission of infectious agents should begin during training in the health professions and be provided to anyone who has an opportunity for contact with patients or medical equipment (eg, nursing and medical staff; therapists and technicians, including respiratory, physical, occupational, radiology, and cardiology personnel; phlebotomists; housekeeping and maintenance staff; and students). in health care facilities, education and training on standard and transmission-based precautions are typically provided at the time of orientation and should be repeated as necessary to maintain competency; updated education and training are necessary when policies and procedures are revised or when a special circumstance occurs, such as an outbreak that requires modification of current practice or adoption of new recommendations. education and training materials and methods appropriate to the hcw's level of responsibility, individual learning habits, and language needs can improve the learning experience. 657, [693] [694] [695] [696] [697] [698] [699] [700] [701] education programs for hcws have been associated with sustained improvement in adherence to best practices and a related decrease in device-associated hais in teaching and nonteaching settings 638, 702 and in medical and surgical icus (coopersmith, 2002 #2563) . several studies have shown that in addition to targeted education to improve specific practices, periodic assessment and feedback of the hcw's knowledge and adherence to recommended practices are necessary to achieve the desired changes and identify continuing education needs. 561, [703] [704] [705] [706] [707] the effectiveness of this approach for isolation practices has been demonstrated in the control of rsv. 116, 683 patients, family members, and visitors can be partners in preventing transmission of infections in health care settings. 9,42,708-710 information on standard precautions, especially hand hygiene, respiratory hygiene/cough etiquette, vaccination (especially against influenza), and other routine infection prevention strategies, may be incorporated into patient information materials provided on admission to the health care facility. additional information on transmission-based precautions is best provided when these precautions are initiated. fact sheets, pamphlets, and other printed material may include information on the rationale for the additional precautions, risks to household members, room assignment for transmission-based precautions purposes, explanation of the use of ppe by hcws, and directions for use of such equipment by family members and visitors. such information may be particularly helpful in the home environment, where household members often have the primary responsibility for adherence to recommended infection control practices. hcws must be available and prepared to explain this material and answer questions as needed. hand hygiene has been frequently cited as the single most important practice to reduce the transmission of infectious agents in health care settings 558, 711, 712 and is an essential element of standard precautions. the term ''hand hygiene'' includes both handwashing with either plain or antiseptic-containing soap and water and the use of alcohol-based products (gels, rinses, foams) that do not require water. in the absence of visible soiling of hands, approved alcohol-based products for hand disinfection are preferred over antimicrobial or plain soap and water because of their superior microbiocidal activity, reduced drying of the skin, and convenience. 558 have been associated with a sustained decrease in the incidence of mrsa and vre infections primarily in icus. 560, 561, [713] [714] [715] [716] the scientific rationale, indications, methods, and products for hand hygiene have been summarized in previous publications. 558, 716 the effectiveness of hand hygiene can be reduced by the type and length of fingernails. 558, 717, 718 individuals wearing artificial nails have been shown to harbor more pathogenic organisms, especially gram-negative bacilli and yeasts, on the nails and in the subungual area compared with individuals with native nails. 719, 720 in 2002, the cdc/hicpac recommended (category ia) that artificial fingernails and extenders not be worn by hcws who have contact with high-risk patients (eg, those in icus and operating rooms), due to the association with outbreaks of gram-negative bacillus and candidal infections as confirmed by molecular typing of isolates. 30, 31, 558, [721] [722] [723] [724] the need to restrict the wearing of artificial fingernails by all hcws who provide direct patient care and those who have contact with other high-risk groups (eg, oncology and cystic fibrosis patients) has not been studied but has been recommended by some experts. 20 currently, such decisions are at the discretion of an individual facility's infection control program. there is less evidence indicating that jewelry affects the quality of hand hygiene. although hand contamination with potential pathogens is increased with ring-wearing, 558, 725 no studies have related this practice to hcw-to-patient transmission of pathogens. ppe refers to various barriers and respirators used alone or in combination to protect mucous membranes, airways, skin, and clothing from contact with infectious agents. the choice of ppe is based on the nature of the patient interaction and/or the likely mode(s) of transmission. specific guidance on the use of ppe is provided in part iii of this guideline. a suggested procedure for donning and removing ppe aimed at preventing skin or clothing contamination is presented in figure 1 . designated containers for used disposable or reusable ppe should be placed in a location convenient to the site of removal, to facilitate disposal and containment of contaminated materials. hand hygiene is always the final step after removing and disposing of ppe. the following sections highlight the primary uses of and criteria for selecting this equipment. ii.e.1. gloves. gloves are used to prevent contamination of hcw hands when (1) anticipating direct contact with blood or body fluids, mucous membranes, nonintact skin and other potentially infectious material; (2) having direct contact with patients who are colonized or infected with pathogens transmitted by the contact route (eg, vre, mrsa, rsv 558, 726, 727 ); or (3) handling or touching visibly or potentially contaminated patient care equipment and environmental surfaces. 72, 73, 558 gloves can protect both patients and hcws from exposure to infectious material that may be carried on hands. 73 the extent to which gloves will protect hcws from transmission of bloodborne pathogens (eg, hiv, hbv, hcv) after a needlestick or other puncture that penetrates the glove barrier has not yet been determined. although gloves may reduce the volume of blood on the external surface of a sharp by 46% to 86%, 728 the residual blood in the lumen of a hollow-bore needle would not be affected; therefore, the effect on transmission risk is unknown. gloves manufactured for health care purposes are subject to fda evaluation and clearance. 729 nonsterile disposable medical gloves made of various materials (eg, latex, vinyl, nitrile) are available for routine patient care. 730 the selection of glove type for nonsurgical use is based on various factors, including the task to be performed, anticipated contact with chemicals and chemotherapeutic agents, latex sensitivity, sizing, and facility policies for creating a latex-free environment. 17, [731] [732] [733] for contact with blood and body fluids during nonsurgical patient care, a single pair of gloves generally provides adequate barrier protection. 733 however, there is considerable variability among gloves; both the quality of the manufacturing process and type of material influence their barrier effectiveness. 734 whereas there is little difference in the barrier properties of unused intact gloves, 735 studies have shown repeatedly that vinyl gloves have higher failure rates than latex or nitrile gloves when tested under simulated and actual clinical conditions. 730, [734] [735] [736] [737] for this reason, either latex or nitrile gloves are preferable for clinical procedures that require manual dexterity or will involve more than brief patient contact. a facility may need to stock gloves in several sizes. heavier, reusable utility gloves are indicated for non-patient care activities, such as handling or cleaning contaminated equipment or surfaces. 11, 14, 738 during patient care, transmission of infectious organisms can be reduced by adhering to the principles of working from ''clean'' to ''dirty'' and confining or limiting contamination to those surfaces directly needed for patient care. it may be necessary to change gloves during the care of a single patient to prevent cross-contamination of body sites. 558, 739 it also may be necessary to change gloves if the patient interaction also involves touching portable computer keyboards or other mobile equipment transported from room to room. discarding gloves between patients is necessary to prevent transmission of infectious material. gloves must not be washed for subsequent reuse, because microorganisms cannot be removed reliably from glove surfaces, and continued glove integrity cannot be ensured. furthermore, glove reuse has been associated with transmission of mrsa and gram-negative bacilli. [740] [741] [742] when gloves are worn in combination with other ppe, they are put on last. gloves that fit snugly around the wrist are preferred for use with an isolation gown, because they will cover the gown cuff and provide a more reliable continuous barrier for the arms, wrists, and hands. proper glove removal will prevent hand contamination (fig 1) . hand hygiene after glove removal further ensures that the hands will not carry potentially infectious material that might have penetrated through unrecognized tears or that could have contaminated the hands during glove removal. 558, 727, 740 ii.e.2. isolation gowns. isolation gowns are used as specified by standard and transmission-based precautions to protect the hcw's arms and exposed body areas and prevent contamination of clothing with blood, body fluids, and other potentially infectious material. 24, 88, 261, [743] [744] [745] the need for and the type of isolation gown selected is based on the nature of the patient interaction, including the anticipated degree of contact with infectious material and potential for blood and body fluid penetration of the barrier. the wearing of isolation gowns and other protective apparel is mandated by the occupational safety and health administration's (osha) bloodborne pathogens standard. 738 clinical and laboratory coats or jackets worn over personal clothing for comfort and/or purposes of identity are not considered ppe. when applying standard precautions, an isolation gown is worn only if contact with blood or body fluid is anticipated. however, when contact precautions are used (ie, to prevent transmission of an infectious agent that is not interrupted by standard precautions alone and is associated with environmental contamination), donning of both gown and gloves on room entry is indicated, to prevent unintentional contact with contaminated environmental surfaces. 54, 72, 73, 88 the routine donning of isolation gowns on entry into an icu or other high-risk area does not prevent or influence potential colonization or infection of patients in those areas, however. 364, [746] [747] [748] [749] isolation gowns are always worn in combination with gloves, and with other ppe when indicated. gowns are usually the first piece of ppe to be donned. full coverage of the arms and body front, from neck to the mid-thigh or below, will ensure protection of clothing and exposed upper body areas. several gown sizes should be available in a health care facility to ensure appropriate coverage for staff members. isolation gowns should be removed before leaving the patient care area to prevent possible contamination of the environment outside the patient's room. isolation gowns should be removed in a manner that prevents contamination of clothing or skin (fig 1) ; the outer, ''contaminated'' side of the gown is turned inward and rolled into a bundle, and then discarded into a designated container for waste or linen to contain contamination. ii.e.3. face protection: masks, goggles, and face shields. ii.e.3.a. masks. masks are used for 3 primary purposes in health care settings: (1) placed on hcws to protect them from contact with infectious material from patients (eg, respiratory secretions and sprays of blood or body fluids), consistent with standard precautions and droplet precautions; (2) placed on hcws engaged in procedures requiring sterile technique, to protect patients from exposure to infectious agents carried in the hcw's mouth or nose; and (3) placed on coughing patients to limit potential dissemination of infectious respiratory secretions from the patient to others (ie, respiratory hygiene/cough etiquette). masks may be used in combination with goggles to protect the mouth, nose, and eyes, or, alternatively, a face shield may be used instead of a mask and goggles to provide more complete protection for the face, as discussed below. masks should not be confused with particulate respirators used to prevent inhalation of small particles that may contain infectious agents transmitted through the airborne route, as described below. the mucous membranes of the mouth, nose, and eyes are susceptible portals of entry for infectious agents; other skin surfaces also may be portals if skin integrity is compromised (by, eg, acne, dermatitis). 66, [750] [751] [752] [753] therefore, use of ppe to protect these body sites is an important component of standard precautions. the protective effect of masks for exposed hcws has been demonstrated previously. 93, 113, 754, 755 procedures that generate splashes or sprays of blood, body fluids, secretions, or excretions (eg, endotracheal suctioning, bronchoscopy, invasive vascular procedures) require either a face shield (disposable or reusable) or a mask and goggles. [93] [94] [95] [96] 113, 115, 261, 738, 756 the wearing of masks, eye protection, and face shields in specified circumstances when blood or body fluid exposure is likely is mandated by osha's bloodborne pathogens standard. 738 appropriate ppe should be selected based on the anticipated level of exposure. two mask types are available for use in health care settings: surgical masks that are cleared by the fda and required to have fluid-resistant properties, and procedure or isolation masks. 757,#2688 to date, no studies comparing mask types to determine whether one mask type provides better protection than another have been published. because procedure/isolation masks are not regulated by the fda, they may be more variable in terms of quality and performance than surgical masks. masks come in various shapes (eg, molded and nonmolded), sizes, filtration efficiency, and method of attachment (eg, ties, elastic, ear loops). health care facilities may find that different types of masks are needed to meet individual hcw needs. ii.e.3.b. goggles and face shields. guidance on eye protection for infection control has been published. 758 the eye protection chosen for specific work situations (eg, goggles or face shield) depends on the circumstances of exposure, other ppe used, and personal vision needs. personal eyeglasses and contact lenses are not considered adequate eye protection (see http://www.cdc.gov/ niosh/topics/eye/eye-infectious.html). niosh guidelines specify that eye protection must be comfortable, allow for sufficient peripheral vision, and adjustable to ensure a secure fit. a health care facility may need to provide several different types, styles, and sizes of eye protection equipment. indirectly vented goggles with a manufacturer's antifog coating may provide the most reliable practical eye protection from splashes, sprays, and respiratory droplets from multiple angles. newer styles of goggles may provide better indirect airflow properties to reduce fogging, as well as better peripheral vision and more size options for fitting goggles to different workers. many styles of goggles fit adequately over prescription glasses with minimal gaps. although effective as eye protection, goggles do not provide splash or spray protection to other parts of the face. the role of goggles in addition to a mask in preventing exposure to infectious agents transmitted through respiratory droplets has been studied only for rsv. reports published in the mid-1980s demonstrated that eye protection reduced occupational transmission of rsv. 759, 760 whether this was due to the prevention hand-eye contact or the prevention of respiratory droplet-eye contact has not been determined. however, subsequent studies demonstrated that rsv transmission is effectively prevented by adherence to standard precautions plus contact precautions and that routine use of goggles is not necessary for this virus. 24, 116, 117, 683, 761 it is important to remind hcws that even if droplet precautions are not recommended for a specific respiratory tract pathogen, protection for the eyes, nose, and mouth using a mask and goggles or a face shield alone is necessary when a splash or spray of any respiratory secretions or other body fluids is likely to occur, as defined in standard precautions. disposable or nondisposable face shields may be used as an alternative to goggles. 758 compared with goggles, a face shield can provide protection to other facial areas besides the eyes. face shields extending from the chin to crown provide better face and eye protection from splashes and sprays; face shields that wrap around the sides may reduce splashes around the edge of the shield. removal of a face shield, goggles, and mask can be performed safely after gloves have been removed and hand hygiene performed. the ties, earpieces, and/or headband used to secure the equipment to the head are considered ''clean'' and thus safe to touch with bare hands. the front of a mask, goggles, and face shield are considered contaminated (fig 1) . ii.e.4. respiratory protection. the subject of respiratory protection as it applies to preventing transmission of airborne infectious agents, including the need for and frequency of fit testing is under scientific review and was the subject of a 2004 cdc workshop. 762 respiratory protection currently requires the use of a respirator with n95 or higher-level filtration to prevent inhalation of infectious particles. information about respirators and respiratory protection programs is summarized in the guideline for preventing transmission of mycobacterium tuberculosis in health care settings. 12 respiratory protection is broadly regulated by osha under the general industry standard for respiratory protection (29 cfr 1910 .134), 763 which requires that us employers in all employment settings implement a program to protect employees from inhalation of toxic materials. osha program components include medical clearance to wear a respirator; provision and use of appropriate respirators, including fit-tested niosh-certified n95 and higher-level particulate filtering respirators; education on respirator use, and periodic reevaluation of the respiratory protection program. when selecting particulate respirators, models with inherently good fit characteristics (ie, those expected to provide protection factors of $ 10% to 95% of wearers) are preferred and theoretically could preclude the need for fit testing. 764, 765 issues pertaining to respiratory protection remain the subject of ongoing debate. information on various types of respirators is available at http://www.cdc.gov/niosh/ npptl/respirators/respsars.html and in several previously published studies. 764, 766, 767 a user-seal check (formerly called a ''fit check'') should be performed by the wearer of a respirator each time that the respirator is donned, to minimize air leakage around the face piece. 768 the optimal frequency of fit testing has not been determined; retesting may be indicated if there is a change in wearer's facial features, onset of a medical condition that would affect respiratory function in the wearer, or a change in the model or size of the respirator that was initially assigned. 12 respiratory protection was first recommended for protection of us hcws from exposure to m tuberculosis in 1989. that recommendation has been maintained in 2 successive revisions of the guidelines for prevention of transmission of tuberculosis in hospitals and other health care settings. 12, 126 the incremental benefit from respirator use, in addition to administrative and engineering controls (ie, aiirs, early recognition of patients likely to have tuberculosis and prompt placement in an aiir, and maintenance of a patient with suspected tuberculosis in an aiir until no longer infectious), for preventing transmission of airborne infectious agents (eg, m tuberculosis) remains undetermined. although some studies have demonstrated effective prevention of m tuberculosis transmission in hospitals in which surgical masks instead of respirators were used in conjunction with other administrative and engineering controls. 636, 769, 770 the cdc currently recommends n95 or higher-level respirators for personnel exposed to patients with suspected or confirmed tuberculosis. currently, this recommendation also holds for other diseases that could be transmitted through the airborne route, including sars 261 and smallpox, 108,129,771 until inhalational transmission is better defined or health care-specific ppe more suitable for preventing infection is developed. wearing of respirators is also currently recommended during the performance of aerosol-generating procedures (eg, intubation, bronchoscopy, suctioning) in patients with sars-cov infection, avian influenza, and pandemic influenza (see appendix a). although airborne precautions are recommended for preventing airborne transmission of measles and varicella-zoster viruses, no data are available on which to base a recommendation for respiratory protection to protect susceptible personnel against these 2 infections. transmission of varicella-zoster virus has been prevented among pediatric patients using negativepressure isolation alone. 772 whether respiratory protection (ie, wearing a particulate respirator) will enhance protection from these viruses has not yet been studied. because most hcws have natural or acquired immunity to these viruses, only immune personnel generally care for patients with these infections. [773] [774] [775] [776] although there is no evidence suggesting that masks are not adequate to protect hcws in these settings, for purposes of consistency and simplicity, or because of difficulties in ascertaining immunity, some facilities may require the use of respirators for entry into all aiirs, regardless of the specific infectious agent present. procedures for safe removal of respirators are provided in figure 1 . in some health care settings, particulate respirators used to provide care for patients with m tuberculosis are reused by the same hcw. this is an acceptable practice providing that the respirator is not damaged or soiled, the fit is not compromised by a change in shape, and the respirator has not been contaminated with blood or body fluids. no data are available on which to base a recommendation regarding the length of time that a respirator may be safely reused. sharps-related injuries. injuries due to needles and other sharps have been associated with transmission of hbv, hcv, and hiv to hcws. 777, 778 the prevention of sharps injuries has always been an essential element of universal precautions and is now an aspect of standard precautions. 1, 779 these include measures to handle needles and other sharp devices in a manner that will prevent injury to the user and to others who may encounter the device during or after a procedure. these measures apply to routine patient care and do not address the prevention of sharps injuries and other blood exposures during surgical and other invasive procedures addressed elsewhere. [780] [781] [782] [783] [784] since 1991, when osha first issued its bloodborne pathogens standard to protect hcws from blood exposure, the focus of regulatory and legislative activity has been on implementing a hierarchy of control measures. this has included focusing attention on removing sharps hazards through the development and use of engineering controls. the federal needlestick safety and prevention act, signed into law in november 2000, authorized osha's revision of its bloodborne pathogens standard to more explicitly require the use of safety-engineered sharps devices. 785 the cdc has provided guidance on sharps injury prevention, 786,787 including guidelines for the design, implementation and evaluation of a comprehensive sharps injury prevention program. 788 ii.f.2. prevention of mucous membrane contact. exposure of mucous membranes of the eyes, nose, and mouth to blood and body fluids has been associated with the transmission of bloodborne viruses and other infectious agents to hcws. 66, 751, 753, 778 the prevention of mucous membrane exposures has always been an element of universal precautions and is now an element of standard precautions for routine patient care 1, 752 and is subject to osha bloodborne pathogen regulations. safe work practices, in addition to wearing ppe, are designed to protect mucous membranes and nonintact skin from contact with potentially infectious material. these include keeping contaminated gloved and ungloved hands from touching the mouth, nose, eyes, or face and positioning patients to direct sprays and splatter away from the caregiver's face. careful placement of ppe before patient contact will help avoid the need to make adjustments to ppe and prevent possible face or mucous membrane contamination during use. in areas where the need for resuscitation is unpredictable, mouthpieces, pocket resuscitation masks with 1-way valves, and other ventilation devices provide an alternative to mouth-to-mouth resuscitation, preventing exposure of the caregiver's nose and mouth to oral and respiratory fluids during the procedure. ii.f.2.a. precautions during aerosol-generating procedures. the performance of procedures that can generate small-particle aerosols (aerosol-generating procedures), such as bronchoscopy, endotracheal intubation, and open suctioning of the respiratory tract, have been associated with transmission of infectious agents to hcws, including m tuberculosis, 789 sars-cov, 93, 94, 98 and n meningitidis. 95 protection of the eyes, nose, and mouth, in addition to gown and gloves, is recommended during performance of these procedures in accordance with standard precautions. the use of a particulate respirator is recommended during aerosol-generating procedures when the aerosol is likely to contain m tuberculosis, sars-cov, or avian or pandemic influenza viruses. ii.g.1. hospitals and long-term care facilities. options for patient placement include single-patient rooms, 2-patient rooms, and multibed wards. of these, single-patient rooms are preferred when transmission of an infectious agent is of concern. although some studies have failed to demonstrate the efficacy of single-patient rooms in preventing hais, 790 other published studies, including one commissioned by the aia and the facility guidelines institute, have documented a beneficial relationship between private rooms and reduced infectious and noninfectious adverse patient outcomes. 791, 792 the aia notes that private rooms are the trend in hospital planning and design. however, most hospitals and ltcfs have multibed rooms and must consider many competing priorities when determining the appropriate room placement for patients (eg, reason for admission; patient characteristics, such as age, gender, and mental status; staffing needs; family requests; psychosocial factors; reimbursement concerns). in the absence of obvious infectious diseases that require specified airborne infection isolation rooms (eg, tuberculosis, sars, chickenpox), the risk of transmission of infectious agents is not always considered when making placement decisions. when only a limited number of single-patient rooms is available, it is prudent to prioritize room assignments for those patients with conditions that facilitate transmission of infectious material to other patients (eg, draining wounds, stool incontinence, uncontained secretions) and those at increased risk of acquisition and adverse outcomes resulting from hais (due to, eg, immunosuppression, open wounds, indwelling catheters, anticipated prolonged length of stay, total dependence on hcws for activities of daily living). 15, 24, 43, 429, 793, 794 single-patient rooms are always indicated for patients placed on airborne precautions in a pe and are preferred for patients requiring contact or droplet precautions. 23, 24, 409, 434, 795, 796 during a suspected or proven outbreak caused by a pathogen whose reservoir is the gastrointestinal tract, the use of single-patient rooms with private bathrooms limits opportunities for transmission, especially when the colonized or infected patient has poor personal hygiene habits or fecal incontinence, or cannot be expected to assist in maintaining procedures that prevent transmission of microorganisms (eg, infants, children, and patients with altered mental status or developmental delay). in the absence of continued transmission, it is not necessary to provide a private bathroom for patients colonized or infected with enteric pathogens as long as personal hygiene practices and standard precautions (especially hand hygiene and appropriate environmental cleaning) are maintained. assignment of a dedicated commode to a patient, and cleaning and disinfecting fixtures and equipment that may have fecal contamination (eg, bathrooms, commodes, 797 scales used for weighing diapers) and the adjacent surfaces with appropriate agents may be especially important when a single-patient room cannot be assigned, because environmental contamination with intestinal tract pathogens is likely from both continent and incontinent patients. 54, 798 the results of several studies that investigated the benefit of a single-patient room in preventing transmission of c difficile were inconclusive. 167, [799] [800] [801] some studies have shown that being in the same room with a colonized or infected patient is not necessarily a risk factor for transmission; 790,802-804 however, for children, the risk of health care-associated diarrhea is increased with the increased number of patients per room. 805 these findings demonstrate that patient factors are important determinants of infection transmission risks. the need for a single-patient room and/or private bathroom for any patient is best determined on a case-by-case basis. cohorting is the practice of grouping together patients who are colonized or infected with the same organism to confine their care to a single area and prevent contact with other patients. cohorts are created based on clinical diagnosis, microbiologic confirmation (when available), epidemiology, and mode of transmission of the infectious agent. avoiding placing severely immunosuppressed patients in rooms with other patients is generally preferred. cohorting has been extensively used for managing outbreaks of mdros, including mrsa, 22 813 rotavirus, 814 and sars. 815 modeling studies provide additional support for cohorting patients to control outbreaks; 816-818 however, cohorting often is implemented only after routine infection control measures have failed to control an outbreak. assigning or cohorting hcws to care only for patients infected or colonized with a single target pathogen limits further transmission of the target pathogen to uninfected patients, 739, 818 but is difficult to achieve in the face of current staffing shortages in hospitals 582 and residential health care sites. [819] [820] [821] however, cohorting of hcws may be beneficial when transmission continues after implementing routine infection control measures and creating patient cohorts. during periods when rsv, human metapneumovirus, 822 parainfluenza, influenza, other respiratory viruses, 823 and rotavirus are circulating in the community, cohorting based on the presenting clinical syndrome is often a priority in facilities that care for infants and young children. 824 for example, during the respiratory virus season, infants may be cohorted based solely on the clinical diagnosis of bronchiolitis, due to the logistical difficulties and costs associated with requiring microbiologic confirmation before room placement and the predominance of rsv during most of the season. however, when available, single-patient rooms are always preferred, because a common clinical presentation (eg, bronchiolitis), can be caused by more than 1 infectious agent. 822, 823, 825 furthermore, the inability of infants and children to contain body fluids, and the close physical contact associated with their care, increases the risk of infection transmission for patients and personnel in this setting. 24, 794 ii.g.2. ambulatory care settings. patients actively infected with or incubating transmissible infectious diseases are frequently seen in ambulatory settings (eg, outpatient clinics, physicians' offices, emergency departments) and potentially expose hcws and other patients, family members, and visitors. 21, 34, 127, 135, 142, 826 in response to the global outbreak of sars in 2003 and in preparation for pandemic influenza, hcws working in outpatient settings are urged to implement source containment measures (eg, asking coughing patients to wear a surgical mask or cover coughing with tissues) to prevent transmission of respiratory infections, beginning at the initial patient encounter, 9,261,827 as described in section iii.a.1.a. signs can be posted at the facility's entrance or at the reception or registration desk requesting that the patient or individuals accompanying the patient promptly inform the receptionist of any symptoms of respiratory infection (eg, cough, flulike illness, increased production of respiratory secretions). the presence of diarrhea, skin rash, or known or suspected exposure to a transmissible disease (eg, measles, pertussis, chickenpox, tuberculosis) also could be added. prompt placement of a potentially infectious patient in an examination room limits the number of exposed individuals in the common waiting area. in waiting areas, maintaining a distance between symptomatic and nonsymptomatic patients (eg, . 3 feet), in addition to source control measures, may limit exposures. however, infections transmitted through the airborne route (eg, m tuberculosis, measles, chickenpox) require additional precautions. 12, 125, 828 patients suspected of having such an infection can wear a surgical mask for source containment, if tolerated, and should be placed in an examination room (preferably an aiir) as soon as possible. if this is not possible, then having the patient wear a mask and segregating the patient from other patients in the waiting area will reduce the risk of exposing others. because the person(s) accompanying the patient also may be infectious, application of the same infection control precautions may be extended to these persons if they are symptomatic. 21, 251, 829 family members accompanying children admitted with suspected m tuberculosis have been found to have unsuspected pulmonary tuberculosis with cavitary lesions, even when asymptomatic. 42, 830 patients with underlying conditions that increase their susceptibility to infection (eg, immunocompromised status 43, 44 or cystic fibrosis 20 ) require special efforts to protect them from exposure to infected patients in common waiting areas. informing the receptionist of their infection risk on arrival allows appropriate steps to further protect these patients from infection. in some cystic fibrosis clinics, to avoid exposure to other patients who could be colonized with b cepacia, patients have been given beepers on registration so that they may leave the area and receive notification to return when an examination room becomes available. 831 ii.g.3. home care. in home care, patient placement concerns focus on protecting others in the home from exposure to an infectious household member. for individuals who are especially vulnerable to adverse outcomes associated with certain infections, it may be beneficial to either remove them from the home or segregate them within the home. persons who are not part of the household may need to be prohibited from visiting during the period of infectivity. for example, in a situation where a patient with pulmonary tuberculosis is contagious and being cared for at home, very young children (age under 4 years) 832 and immunocompromised persons who have not yet been infected should be removed or excluded from the household. during the sars outbreak of 2003, segregation of infected persons during the communicable phase of the illness was found to be beneficial in preventing household transmission. 249, 833 several principles guide the transport of patients requiring transmission-based precautions. in the inpatient and residential settings, these include the following: 1. limiting transport of such patients to essential purposes, such as diagnostic and therapeutic procedures that cannot be performed in the patient's room. 2. when transport is necessary, applying appropriate barriers on the patient (eg, mask, gown, wrapping in sheets or use of impervious dressings to cover the affected areas) when infectious skin lesions or drainage are present, consistent with the route and risk of transmission. 3. notifying hcws in the receiving area of the patient's impending arrival and of the necessary precautions to prevent transmission. 4. for patients being transported outside the facility, informing the receiving facility and the medi-van or emergency vehicle personnel in advance about the type of transmission-based precautions being used. for tuberculosis, additional precautions may be needed in a small shared air space, such as in an ambulance. 12 cleaning and disinfecting noncritical surfaces in patient care areas is an aspect of standard precautions. in general, these procedures do not need to be changed for patients on transmission-based precautions. the cleaning and disinfection of all patient care areas is important for frequently touched surfaces, especially those closest to the patient, which are most likely to be contaminated (eg, bedrails, bedside tables, commodes, doorknobs, sinks, surfaces and equipment in close proximity to the patient). 11, 72, 73, 834 the frequency or intensity of cleaning may need to be changed, based on the patient's level of hygiene and the degree of environmental contamination and for certain infectious agents with reservoirs in the intestinal tract. 54 this may be particularly important in ltcfs and pediatric facilities, where patients with stool and urine incontinence are encountered more frequently. in addition, increased frequency of cleaning may be needed in a pe to minimize dust accumulation. 11 special recommendations for cleaning and disinfecting environmental surfaces in dialysis centers have been published previously. 18 in all health care settings, administrative, staffing, and scheduling activities should prioritize the proper cleaning and disinfection of surfaces that could be implicated in transmission. during a suspected or proven outbreak in which an environmental reservoir is suspected, routine cleaning procedures should be reviewed, and the need for additional trained cleaning staff should be assessed. adherence should be monitored and reinforced to promote consistent and correct cleaning. us environmental protection agency-registered disinfectants or detergents/disinfectants that best meet the overall needs of the health care facility for routine cleaning and disinfection should be selected. 11, 835 in general, use of the existing facility detergent/disinfectant according to the manufacturer's recommendations for amount, dilution, and contact time is sufficient to remove pathogens from surfaces of rooms where colonized or infected individuals were housed. this includes those pathogens that are resistant to multiple classes of antimicrobial agents (eg, c difficile, vre, mrsa, mdr-gnb 11, 24, 88, 434, 745, 795, 836 ). most often, environmental reservoirs of pathogens during outbreaks are related to a failure to follow recommended procedures for cleaning and disinfection, rather than to the specific cleaning and disinfectant agents used. [837] [838] [839] [840] certain pathogens (eg, rotavirus, noroviruses, c difficile) may be resistant to some routinely used hospital disinfectants. 274, 291, [841] [842] [843] [844] [845] [846] the role of specific disinfectants in limiting transmission of rotavirus has been demonstrated experimentally. 841 also, because c difficile may display increased levels of spore production when exposed to non-chlorine-based cleaning agents, and because these spores are more resistant than vegetative cells to commonly used surface disinfectants, some investigators have recommended the use of a 1:10 dilution of 5.25% sodium hypochlorite (household bleach) and water for routine environmental disinfection of rooms of patients with c difficile when there is continued transmission. 843, 847 one study found an association between the use of a hypochlorite solution and decreased rates of c difficile infections. 846 the need to change disinfectants based on the presence of these organisms can be determined in consultation with the infection control committee. 11, 846, 847 detailed recommendations for disinfection and sterilization of surfaces and medical equipment that have been in contact with prion-containing tissue or high risk body fluids, and for cleaning of blood and body substance spills, are available in the guidelines for environmental infection control in health care facilities 11 and in the guideline for disinfection and sterilization. 847 medical equipment and instruments/devices must be cleaned and maintained according to the manufacturers' instructions to prevent patient-to-patient transmission of infectious agents. 86, 87, 324, 848 cleaning to remove organic material always must precede highlevel disinfection and sterilization of critical and semicritical instruments and devices, because residual proteinacous material reduces the effectiveness of the disinfection and sterilization processes. 835, 847 noncritical equipment, such as commodes, intravenous pumps, and ventilators, must be thoroughly cleaned and disinfected before being used on another patient. all such equipment and devices should be handled in a manner that will prevent hcw and environmental contact with potentially infectious material. it is important to include computers and personal digital assistants used in patient care in policies for cleaning and disinfection of noncritical items. the literature on contamination of computers with pathogens has been summarized, 849 and 2 reports have linked computer contamination to colonization and infections in patients. 850, 851 although keyboard covers and washable keyboards that can be easily disinfected are available, the infection control benefit of these items and their optimal management have not yet been determined. in all health care settings, providing patients who are on transmission-based precautions with dedicated noncritical medical equipment (eg, stethoscope, blood pressure cuff, electronic thermometer) has proven beneficial for preventing transmission. 74, 89, 739, 852, 853 when this is not possible, disinfection of this equipment after each use is recommended. other previously published guidelines should be consulted for detailed guidance in developing specific protocols for cleaning and reprocessing medical equipment and patient care items in both routine and special circumstances. 11, 14, 18, 20, 739, 835, 847 in home care, it is preferable to remove visible blood or body fluids from durable medical equipment before it leaves the home. equipment can be cleaned onsite using a detergent/disinfectant and, when possible, should be placed in a plastic bag for transport to the reprocessing location. 20,738 although soiled textiles, including bedding, towels, and patient or resident clothing, may be contaminated with pathogenic microorganisms, the risk of disease transmission is negligible if these textiles are handled, transported, and laundered in a safe manner. 11, 854, 855 key principles for handling soiled laundry are (1) avoiding shaking the items or handling them in any way that may aerosolize infectious agents, (2) avoiding contact of one's body and personal clothing with the soiled items being handled, and (3) containing soiled items in a laundry bag or designated bin. if a laundry chute is used, it must be maintained to minimize dispersion of aerosols from contaminated items. 11 methods of handling, transporting, and laundering soiled textiles are determined by organizational policy and any applicable regulations; 738 guidance is provided in the guidelines for environmental infection control in health care facilities. 11 rather than rigid rules and regulations, hygienic and common sense storage and processing of clean textiles is recommended. 11, 856 when laundering is done outside of a health care facility, the clean items must be packaged or completely covered and placed in an enclosed space during transport to prevent contamination with outside air or construction dust that could contain infectious fungal spores that pose a risk for immunocompromised patients. 11 institutions are required to launder garments used as ppe and uniforms visibly soiled with blood or infective material. 738 little data exist on the safety of home laundering of hcw uniforms, but no increase in infection rates was observed in the one published study, 857 and no pathogens were recovered from home-or hospital-laundered scrubs in another study. 858 in the home, textiles and laundry from patients with potentially transmissible infectious pathogens do not require special handling or separate laundering and may be washed with warm water and detergent. 11, 857, 858 the management of solid waste emanating from the health care environment is subject to federal and state regulations for medical and nonmedical waste. 859, 860 no additional precautions are needed for nonmedical solid waste removed from rooms of patients on transmission-based precautions. solid waste may be contained in a single bag of sufficient strength. 861 the combination of hot water and detergents used in dishwashers is sufficient to decontaminate dishware and eating utensils. therefore, no special precautions are needed for dishware (eg, dishes, glasses, cups) or eating utensils. reusable dishware and utensils may be used for patients requiring transmission-based precautions. in the home and other communal settings, eating utensils and drinking vessels should not be shared, consistent with principles of good personal hygiene and to help prevent transmission of respiratory viruses, herpes simplex virus, and infectious agents that infect the gastrointestinal tract and are transmitted by the fecal/oral route (eg, hepatitis a virus, noroviruses). if adequate resources for cleaning utensils and dishes are not available, then disposable products may be used. important adjunctive measures that are not considered primary components of programs to prevent transmission of infectious agents but nonetheless improve the effectiveness of such programs include (1) antimicrobial management programs, (2) postexposure chemoprophylaxis with antiviral or antibacterial agents, (3) vaccines used both for pre-exposure and postexposure prevention, and (4) screening and restricting visitors with signs of transmissible infections. detailed discussion of judicious use of antimicrobial agents is beyond the scope of this document; however, this topic has been addressed in a previous cdc guideline (http://www.cdc.gov/ncidod/dhqp/pdf/ar/ mdroguideline2006.pdf). ii.n.1. chemoprophylaxis. antimicrobial agents and topical antiseptics may be used to prevent infection and potential outbreaks of selected agents. infections for which postexposure chemoprophylaxis is recommended under defined conditions include b pertussis, 17,862 n meningitides, 863 b anthracis after environmental exposure to aeosolizable material, 864 influenza virus, 610 hiv, 865 and group a streptococcus. 160 orally administered antimicrobials also may be used under defined circumstances for mrsa decolonization of patients or hcws. 866 another form of chemoprophylaxis involves the use of topical antiseptic agents. for example, triple dye is routinely used on the umbilical cords of term newborns to reduce the risk of colonization, skin infections, and omphalitis caused by s aureus, including mrsa, and group a streptococcus. 867, 868 extension of the use of triple dye to low birth weight infants in a nicu was one component of a program that controlled a long-standing mrsa outbreak. 22 topical antiseptics (eg, mupirocin) also are used for decolonization of hcws or selected patients colonized with mrsa, as discussed in the mdro guideline 866, [869] [870] [871] [872] ii.n.2. immunoprophylaxis. certain immunizations recommended for susceptible hcws have decreased the risk of infection and the potential for transmission in health care facilities. 17, 873 the osha mandate requiring employers to offer hbv vaccination to hcws has played a substantial role in the sharp decline in incidence of occupational hbv infection. 777, 874 the routine administration of varicella vaccine to hcws has decreased the need to place susceptible hcws on administrative leave after exposure to patients with varicella. 774 in addition, reports of health care-associated transmission of rubella in obstetric clinics 33, 875 and measles in acute care settings 34 demonstrate the importance of immunization of susceptible hcws against childhood diseases. many states have requirements for vaccination of hcws for measles and rubella in the absence of evidence of immunity. annual influenza vaccine campaigns targeted at patients and hcws in ltcfs and acute care settings have been instrumental in preventing or limiting institutional outbreaks; consequently, increasing attention is being directed toward improving influenza vaccination rates in hcws. 35, 610, 689, [876] [877] [878] transmission of b pertussis in health care facilities has been associated with large and costly outbreaks that include both hcws and patients. 17, 36, 41, 100, 682, 826, 879, 880 hcws in close contact with infants with pertussis are at particularly high risk because of waning immunity and, until 2005, the absence of a vaccine appropriate for adults. but 2 acellular pertussis vaccines were licensed in the united states in 2005, 1 for use in individuals age 11 to 18 years and the other for use in those age 10 to 64 years. 881 current advisory committee on immunization practices provisional recommendations include immunization of adolescents and adults, especially those in contact with infants under age 12 months and hcws with direct patient contact. 882, 883 immunization of children and adults will help prevent the introduction of vaccine-preventable diseases into health care settings. the recommended immunization schedule for children is published annually in the january issues of the morbidity and mortality weekly report, with interim updates as needed. 884, 885 an adult immunization schedule also is available for healthy adults and those with special immunization needs due to high-risk medical conditions. 886 some vaccines are also used for postexposure prophylaxis of susceptible individuals, including varicella, 887 influenza, 610 hepatitis b, 777 and smallpox 225 vaccines. 17, 873 in the future, administration of a newly developed s aureus conjugate vaccine (still under investigation) to selected patients may provide a novel method of preventing health care-associated s aureus (including mrsa) infections in high-risk groups (eg, hemodialysis patients and candidates for selected surgical procedures). 888, 889 immune globulin preparations also are used for postexposure prophylaxis of certain infectious agents under specified circumstances (eg, varicella-zoster virus, hbv, rabies, measles and hepatitis a virus 17, 832, 873 ). the rsv monoclonal antibody preparation palivizumab may have contributed to controlling a nosocomial outbreak of rsv in one nicu, but there is insufficient evidence to support a routine recommendation for its use in this setting. 890 ii.n. 3 24, 43, 44, 372 and sars 21, [252] [253] [254] . effective methods for visitor screening in health care settings have not yet been studied, however. visitor screening is especially important during community outbreaks of infectious diseases and for high-risk patient units. sibling visits are often encouraged in birthing centers, postpartum rooms, pediatric inpatient units, picus, and residential settings for children; in hospital settings, a child visitor should visit only his or her own sibling. screening of visiting siblings and other children before they are allowed into clinical areas is necessary to prevent the introduction of childhood illnesses and common respiratory infections. screening may be passive, through the use of signs to alert family members and visitors with signs and symptoms of communicable diseases not to enter clinical areas. more active screening may include the completion of a screening tool or questionnaire to elicit information related to recent exposures or current symptoms. this information is reviewed by the facility staff, after which the visitor is either permitted to visit or is excluded. 832 family and household members visiting pediatric patients with pertussis and tuberculosis may need to be screened for a history of exposure, as well as signs and symptoms of current infection. potentially infectious visitors are excluded until they receive appropriate medical screening, diagnosis, or treatment. if exclusion is not considered to be in the best interest of the patient or family (ie, primary family members of critically or terminally ill patients), then the symptomatic visitor must wear a mask while in the health care facility and remain in the patient's room, avoiding exposure to others, especially in public waiting areas and the cafeteria. visitor screening is used consistently on hsct units. 15, 43 however, considering the experience during the 2003 sars outbreaks and the potential for pandemic influenza, developing effective visitor screening systems will be beneficial. 9 education concerning respiratory hygiene/cough etiquette is a useful adjunct to visitor screening. ii.n.3.b. use of barrier precautions by visitors. the use of gowns, gloves, and masks by visitors in health care settings has not been addressed specifically in the scientific literature. some studies included the use of gowns and gloves by visitors in the control of mdros but did not perform a separate analysis to determine whether their use by visitors had a measurable impact. [892] [893] [894] family members or visitors who are providing care to or otherwise are in very close contact with the patient (eg, feeding, holding) may also have contact with other patients and could contribute to transmission in the absence of effective barrier precautions. specific recommendations may vary by facility or by unit and should be determined by the specific level of interaction. there are 2 tiers of hicpac/cdc precautions to prevent transmission of infectious agents, standard precautions and transmission-based precautions. standard precautions are intended to be applied to the care of all patients in all health care settings, regardless of the suspected or confirmed presence of an infectious agent. implementation of standard precautions constitutes the primary strategy for the prevention of health care-associated transmission of infectious agents among patients and hcws. transmission-based precautions are for patients who are known or suspected to be infected or colonized with infectious agents, including certain epidemiologically important pathogens, which require additional control measures to effectively prevent transmission. because the infecting agent often is not known at the time of admission to a health care facility, transmission-based precautions are used empirically, according to the clinical syndrome and the likely etiologic agents at the time, and then modified when the pathogen is identified or a transmissible infectious etiology is ruled out. examples of this syndromic approach are presented in table 2 . the hicpac/cdc guidelines also include recommendations for creating a protective environment for allogeneic hsct patients. the specific elements of standard and transmission-based precautions are discussed in part ii of this guideline. in part iii, the circumstances in which standard precautions, transmission-based precautions, and a protective environment are applied are discussed. tables 4 and 5 summarize the key elements of these sets of precautions standard precautions combine the major features of universal precautions 779, 895 and body substance isolation 639 and are based on the principle that all blood, body fluids, secretions, excretions except sweat, nonintact skin, and mucous membranes may contain transmissible infectious agents. standard precautions include a group of infection prevention practices that apply to all patients, regardless of suspected or confirmed infection status, in any setting in which health care is delivered (table 4 ). these include hand hygiene; use of gloves, gown, mask, eye protection, or face shield, depending on the anticipated exposure; and safe injection practices. also, equipment or items in the patient environment likely to have been contaminated with infectious body fluids must be handled in a manner to prevent transmission of infectious agents (eg, wear gloves for direct contact, contain heavily soiled equipment, properly clean and disinfect or sterilize reusable equipment before use on another patient). the application of standard precautions during patient care is determined by the nature of the hcw-patient interaction and the extent of anticipated blood, body fluid, or pathogen exposure. for some interactions (eg, performing venipuncture), only gloves may be needed; during other interactions (eg, intubation), use of gloves, gown, and face shield or mask and goggles is necessary. education and training on the principles and rationale for recommended practices are critical elements of standard precautions because they facilitate appropriate decision-making and promote adherence when hcws are faced with new circumstances. 654, [680] [681] [682] [683] [684] [685] an example of the importance of the use of standard precautions is intubation, especially under emergency circumstances when infectious agents may not be suspected, but later are identified (eg, sars-cov, n meningitides). the application of standard precautions is described below and summarized in table 4 . guidance on donning and removing gloves, gowns and other ppe is presented in figure 1 . standard precautions are also intended to protect patients by ensuring that hcws do not carry infectious agents to patients on their hands or via equipment used during patient care. 21, 254, 896 the strategy proposed has been termed respiratory hygiene/cough etiquette 9, 827 and is intended to be incorporated into infection control practices as a new component of standard precautions. the strategy is targeted at patients and accompanying family members and friends with undiagnosed transmissible respiratory infections, and applies to any person with signs of illness including cough, congestion, rhinorrhea, or increased production of respiratory secretions when entering a health care facility. 40, 41, 43 the term cough etiquette is derived from recommended source control measures for m tuberculosis. 12, 126 the elements of respiratory hygiene/cough etiquette include (1) education of health care facility staff, patients, and visitors; (2) posted signs, in language(s) appropriate to the population served, with instructions to patients and accompanying family members or friends; (3) source control measures (eg, covering the mouth/nose with a tissue when coughing and prompt disposal of used tissues, using surgical masks on the coughing person when tolerated and appropriate); (4) hand hygiene after contact with respiratory secretions; and (5) spatial separation, ideally .3 feet, of persons with respiratory infections in common waiting areas when possible. covering sneezes and coughs and placing masks on coughing patients are proven means of source containment that prevent infected persons from dispersing respiratory secretions into the air. 107, 145, 897, 898 masking may be difficult in some settings, (eg, pediatrics), in which case the emphasis by necessity may be on cough etiquette. 899 physical proximity of , 3 feet has been associated with an increased risk for transmission of infections through the droplet route (eg, n meningitidis 103 and group a streptococcus 114 ) and thus supports the practice of distancing infected persons from others who are not infected. the effectiveness of good hygiene practices, especially hand hygiene, in preventing transmission of viruses and reducing the incidence of respiratory infections both within and outside [900] [901] [902] health care settings is summarized in several reviews. 558, 716, 903 these measures should be effective in decreasing the risk of transmission of pathogens contained in large respiratory droplets (eg, influenza virus, 23 adenovirus, 111 b pertussis, 826 and m pneumoniae 112 ). although fever will be present in many respiratory infections, patients with pertussis and mild upper respiratory tract infections are often afebrile. therefore, the absence of fever does not always exclude a respiratory infection. patients who have asthma, allergic rhinitis, or chronic obstructive lung disease also may be coughing and sneezing. although these patients often are not infectious, cough etiquette measures are prudent. hcws are advised to observe droplet precautions (ie, wear a mask) and hand hygiene when examining and caring for patients with signs and symptoms of a respiratory infection. hcws who have a respiratory infection are advised to avoid direct patient contact, especially with high-risk patients. if this is not possible, then a mask should be worn while providing patient care. iii.a.1.b. safe injection practices. the investigation of 4 large outbreaks of hbv and hcv among patients in ambulatory care facilities in the united states identified a need to define and reinforce safe injection practices. 452 the 4 outbreaks occurred in a private medical practice, a pain clinic, an endoscopy clinic, and a hematology/oncology clinic. the primary breaches in infection control practice that contributed to these outbreaks were reinsertion of used needles into a multiple-dose vial or solution container (eg, saline bag) and use of a single needle/syringe to administer intravenous medication to multiple patients. in 1 of these outbreaks, preparation of medications in the same workspace where used needle/syringes were dismantled also may have been a contributing factor. these and other outbreaks of viral hepatitis could have been prevented by adherence to basic principles of aseptic technique for the preparation and administration of parenteral medications. 452, 453 these include the use of a sterile, single-use, disposable needle and syringe for each injection given and prevention of contamination of injection equipment and medication. whenever possible, use of single-dose vials is preferred over multiple-dose vials, especially when medications will be administered to multiple patients. outbreaks related to unsafe injection practices indicate that some hcws are unaware of, do not understand, or do not adhere to basic principles of infection control and aseptic technique. a survey of us health care workers who provide medication through injection found that 1% to 3% reused the same needle and/or syringe on multiple patients. 904 among the deficiencies identified in recent outbreaks were a lack of oversight of personnel and failure to follow up on reported breaches in infection control practices in ambulatory settings. therefore, to ensure that all hcws understand and adhere to recommended practices, principles of infection control and aseptic technique need to be reinforced in training programs and incorporated into institutional polices that are monitored for adherence. 453 iii.a.1.c. infection control practices for special lumbar puncture procedures. in 2004, the cdc investigated 8 cases of postmyelography meningitis that either were reported to the cdc or identified through a survey of the emerging infections network of the infectious disease society of america. blood and/or cerebrospinal fluid of all 8 cases yielded streptococcal species consistent with oropharyngeal flora and there were changes in the csf indices and clinical status indicative of bacterial meningitis. equipment and products used during these procedures (eg, contrast media) were excluded as probable sources of contamination. procedural details available for 7 cases determined that antiseptic skin preparations and sterile gloves had been used. however, none of the clinicians wore a face mask, giving rise to the speculation that droplet transmission of oralpharyngeal flora was the most likely explanation for these infections. bacterial meningitis after myelography and other spinal procedures (eg, lumbar puncture, spinal and epidural anesthesia, intrathecal chemotherapy) has been reported previously. [905] [906] [907] [908] [909] [910] [911] [912] [913] [914] as a result, the question of whether face masks should be worn to prevent droplet spread of oral flora during spinal procedures (eg, myelography, lumbar puncture, spinal anesthesia) has been debated. 915, 916 face masks are effective in limiting the dispersal of oropharyngeal droplets 917 and are recommended for the placement of central venous catheters. 918 in october 2005, hicpac reviewed the evidence and concluded that there is sufficient experience to warrant the additional protection of a face mask for the individual placing a catheter or injecting material into the spinal or epidural space. there are 3 categories of transmission-based precautions: contact precautions, droplet precautions, and airborne precautions. transmission-based precautions are used when the route(s) of transmission is (are) not completely interrupted using standard precautions alone. for some diseases that have multiple routes of transmission (eg, sars), more than 1 transmission-based precautions category may be used. when used either singly or in combination, they are always used in addition to standard precautions. see appendix a for recommended precautions for specific infections. when transmission-based precautions are indicated, efforts must be made to counteract possible adverse effects on patients (ie, anxiety, depression and other mood disturbances, 919-921 perceptions of stigma, 922 reduced contact with clinical staff, [923] [924] [925] and increases in preventable adverse events 564 ) to improve acceptance by the patients and adherence by hcws. iii.b.1. contact precautions. contact precautions are intended to prevent transmission of infectious agents, including epidemiologically important microorganisms, which are spread by direct or indirect contact with the patient or the patient's environment as described in section i.b.3.a. the specific agents and circumstance for which contact precautions are indicated are found in appendix a. the application of contact precautions for patients infected or colonized with mdros is described in the 2006 hicpac/cdc mdro guideline. 926 contact precautions also apply where the presence of excessive wound drainage, fecal incontinence, or other discharges from the body suggest an increased potential for extensive environmental contamination and risk of transmission. a single-patient room is preferred for patients who require contact precautions. when a single-patient room is not available, consultation with infection control personnel is recommended to assess the various risks associated with other patient placement options (eg, cohorting, keeping the patient with an existing roommate). in multipatient rooms, $ 3 feet spatial separation between beds is advised to reduce the opportunities for inadvertent sharing of items between the infected/colonized patient and other patients. hcws caring for patients on contact precautions wear a gown and gloves for all interactions that may involve contact with the patient or potentially contaminated areas in the patient's environment. donning ppe on room entry and discarding before exiting the patient room is done to contain pathogens, especially those that have been implicated in transmission through environmental contamination (eg, vre, c difficile, noroviruses and other intestinal tract pathogens, rsv). 54, 72, 73, 78, 273, 274, 739 iii.b.2. droplet precautions. droplet precautions are intended to prevent transmission of pathogens spread through close respiratory or mucous membrane contact with respiratory secretions as described in section i.b.3.b. because these pathogens do not remain infectious over long distances in a health care facility, special air handling and ventilation are not required to prevent droplet transmission. infectious agents for which droplet precautions are indicated are listed in appendix a and include b pertussis, influenza virus, adenovirus, rhinovirus, n meningitides, and group a streptococcus (for the first 24 hours of antimicrobial therapy). a single-patient room is preferred for patients who require droplet precautions. when a single-patient room is not available, consultation with infection control personnel is recommended to assess the various risks associated with other patient placement options (eg, cohorting, keeping the patient with an existing roommate). spatial separation of $ 3 feet and drawing the curtain between patient beds is especially important for patients in multibed rooms with infections transmitted by the droplet route. hcws wear a mask (a respirator is not necessary) for close contact with infectious patient; the mask is generally donned on room entry. patients on droplet precautions who must be transported outside of the room should wear a mask if tolerated and follow respiratory hygiene/cough etiquette. iii.b.3. airborne precautions. airborne precautions prevent transmission of infectious agents that remain infectious over long distances when suspended in the air (eg, rubeola virus [measles], varicella virus [chickenpox], m tuberculosis, and possibly sars-cov), as described in section i.b.3.c and appendix a. the preferred placement for patients who require airborne precautions is in an aiir, a single-patient room equipped with special air handling and ventilation capacity that meet the aia/facility guidelines institute standards for aiirs (ie, monitored negative pressure relative to the surrounding area; 12 air exchanges per hour for new construction and renovation and 6 air exchanges per hour for existing facilities; air exhausted directly to the outside or recirculated through hepa filtration before return). 12, 13 some states require the availability of such rooms in hospitals, emergency departments, and nursing homes that care for patients with m tuberculosis. a respiratory protection program that includes education about use of respirators, fit testing, and user seal checks is required in any facility with aiirs. in settings where airborne precautions cannot be implemented due to limited engineering resources (eg, physician offices), masking the patient, placing the patient in a private room (eg, office examination room) with the door closed, and providing n95 or higher-level respirators or masks if respirators are not available for hcws will reduce the likelihood of airborne transmission until the patient is either transferred to a facility with an aiir or returned to the home environment, as deemed medically appropriate. hcws caring for patients on airborne precautions wear a mask or respirator, depending on the disease-specific recommendations (see section ii.e.4, table 2 , and appendix a), that is donned before room entry. whenever possible, nonimmune hcws should not care for patients with vaccine-preventable airborne diseases (eg, measles, chickenpox, smallpox). diagnosis of many infections requires laboratory confirmation. because laboratory tests, especially those that depend on culture techniques, often require 2 or more days for completion, transmission-based precautions must be implemented while test results are pending, based on the clinical presentation and likely pathogens. use of appropriate transmission-based precautions at the time a patient develops symptoms or signs of transmissible infection, or arrives at a health care facility for care, reduces transmission opportunities. although it is not possible to identify prospectively all patients needing transmission-based precautions, certain clinical syndromes and conditions carry a sufficiently high risk to warrant their use empirically while confirmatory tests are pending (see table 2 ). icps are encouraged to modify or adapt this table according to local conditions. transmission-based precautions remain in effect for limited periods (ie, while the risk for transmission of the infectious agent persists or for the duration of the illness (see appendix a). for most infectious diseases, this duration reflects known patterns of persistence and shedding of infectious agents associated with the natural history of the infectious process and its treatment. for some diseases (eg, pharyngeal or cutaneous diphtheria, rsv), transmission-based precautions remain in effect until culture or antigen-detection test results document eradication of the pathogen and, for rsv, symptomatic disease is resolved. for other diseases (eg, m tuberculosis), state laws and regulations and health care facility policies may dictate the duration of precautions. 12 in immunocompromised patients, viral shedding can persist for prolonged periods of time (many weeks to months) and transmission to others may occur during that time; therefore, the duration of contact and/or droplet precautions may be prolonged for many weeks. 499, [927] [928] [929] [930] [931] [932] the duration of contact precautions for patients who are colonized or infected with mdros remains undefined. mrsa is the only mdro for which effective decolonization regimens are available. 866 however, carriers of mrsa who have negative nasal cultures after a course of systemic or topical therapy may resume shedding mrsa in the weeks after therapy. 933, 934 although early guidelines for vre suggested discontinuation of contact precautions after 3 stool cultures obtained at weekly intervals proved negative, 739 subsequent experiences have indicated that such screening may fail to detect colonization that can persist for . 1 year. 27, [935] [936] [937] likewise, available data indicate that colonization with vre, mrsa, 938 and possibly mdr-gnb can persist for many months, especially in the presence of severe underlying disease, invasive devices, and recurrent courses of antimicrobial agents. it may be prudent to assume that mdro carriers are colonized permanently and manage them accordingly. alternatively, an interval free of hospitalizations, antimicrobial therapy, and invasive devices (eg, 6 or 12 months) before reculturing patients to document clearance of carriage may be used. determination of the best strategy awaits the results of additional studies. see the 2006 hicpac/cdc mdro guideline 926 for a discussion of possible criteria to discontinue contact precautions for patients colonized or infected with mdros. although transmission-based precautions generally apply in all health care settings, exceptions exist. for example, in home care, aiirs are not available. furthermore, family members already exposed to diseases such as varicella and tuberculosis would not use masks or respiratory protection, but visiting hcws would need to use such protection. similarly, management of patients colonized or infected with mdros may necessitate contact precautions in acute care hospitals and in some ltcfs when there is continued transmission, but the risk of transmission in ambulatory care and home care has not been defined. consistent use of standard precautions may suffice in these settings, but more information is needed. a pe is designed for allogeneic hsct patients to minimize fungal spore counts in the air and reduce the risk of invasive environmental fungal infections (see table 5 for specifications). 11, [13] [14] [15] the need for such controls has been demonstrated in studies of aspergillosis outbreaks associated with construction. 11, 14, 15, 157, 158 as defined by the aia 13 and presented in detail in the cdc's 2003 guideline for environmental infection control in health care facilities, 11,860 air quality for hsct patients is improved through a combination of environmental controls that include (1) hepa filtration of incoming air, (2) directed room air flow, (3) positive room air pressure relative to the corridor, (4) well-sealed rooms (including sealed walls, floors, ceilings, windows, electrical outlets) to prevent flow of air from the outside, (5) ventilation to provide $ 12 air changes per hour, (6) strategies to minimize dust (eg, scrubbable surfaces rather than upholstery 939 and carpet, 940 and routinely cleaning crevices and sprinkler heads), and (7) prohibiting dried and fresh flowers and potted plants in the rooms of hsct patients. the latter is based on molecular typing studies that have found indistinguishable strains of aspergillus terreus in patients with hematologic malignancies and in potted plants in the vicinity of the patients. [941] [942] [943] the desired quality of air may be achieved without incurring the inconvenience or expense of laminar airflow. 15, 157 to prevent inhalation of fungal spores during periods when construction, renovation, or other dust-generating activities that may be ongoing in and around the health care facility, it has been recommended that severely immunocompromised patients wear a high-efficiency respiratory protection device (eg, an n95 respirator) when they leave the pe. 11, 14, 944 the use of masks or respirators by hsct patients when they are outside of the pe for prevention of environmental fungal infections in the absence of construction has not been evaluated. a pe does not include the use of barrier precautions beyond those indicated for standard precuations and transmission-based precautions. no published reports support the benefit of placing patients undergoing solid organ transplantation or other immunocompromised patients in a pe. these recommendations are designed to prevent transmission of infectious agents among patients and hcws in all settings where health care is delivered. as in other cdc/hicpac guidelines, each recommendation is categorized on the basis of existing scientific data, theoretical rationale, applicability, and, when possible, economic impact. the cdc/hicpac system for categorizing recommendations is as follows: category ia. strongly recommended for implementation and strongly supported by well-designed experimental, clinical, or epidemiologic studies. category ib. strongly recommended for implementation and supported by some experimental, clinical, or epidemiologic studies and a strong theoretical rationale. category ic. required for implementation, as mandated by federal and/or state regulation or standard. category ii. suggested for implementation and supported by suggestive clinical or epidemiologic studies or a theoretical rationale. no recommendation; unresolved issue. practices for which insufficient evidence or no consensus regarding efficacy exists. health care organization administrators should ensure the implementation of recommendations specified in this section. agents into the objectives of the organization's patient and occupational safety programs. 542 assume that every person is potentially infected or colonized with an organism that could be transmitted in the health care setting and apply the following infection control practices during the delivery of health care. iv.a.1. during the delivery of health care, avoid unnecessary touching of surfaces in close proximity to the patient to prevent both contamination of clean hands from environmental surfaces and transmission of pathogens from contaminated hands to surfaces. 72 airborne precautions does not need to wear a mask or respirator during transport if the patient is wearing a mask and infectious skin lesions are covered. category ii v.d.6. exposure management immunize or provide the appropriate immune globulin to susceptible persons as soon as possible after unprotected contact (ie, exposure) to a patient with measles, varicella, or smallpox: category ia d administer measles vaccine to exposed susceptible persons within 72 hours after the exposure or administer immune globulin within 6 days of the exposure event for high-risk persons in whom vaccine is contraindicated. 17,1030-1033 d administer varicella vaccine to exposed susceptible persons within 120 hours after the exposure or administer varicella immune globulin (vzig or an alternative product), when available, within 96 hours for high-risk persons in whom vaccine is contraindicated (eg, immunocompromised patients, pregnant women, newborns whose mother's varicella onset was , 5 days before or within 48 hours after delivery). 887,1033-1035 d administer smallpox vaccine to exposed susceptible persons within 4 days after exposure. 108 vi. protective environment (see table 4 airborne infection isolation room (aiir). formerly known as a negative-pressure isolation room, an aiir is a single-occupancy patient care room used to isolate persons with a suspected or confirmed airborne infectious disease. environmental factors are controlled in aiirs to minimize the transmission of infectious agents that are usually transmitted from person to person by droplet nuclei associated with coughing or aerosolization of contaminated fluids. aiirs should provide negative pressure in the room (so that air flows under the door gap into the room), an air flow rate of 6 to 12 air changes per hour (ach) (6 ach for existing structures, 12 ach for new construction or renovation), and direct exhaust of air from the room to the outside of the building or recirculation of air through a highefficiency particulate air filter before returning to circulation. ( ambulatory care setting. a facility that provides health care to patients who do not remain overnight; examples include hospital-based outpatient clinics, non-hospital-based clinics and physician offices, urgent care centers, surgicenters, free-standing dialysis centers, public health clinics, imaging centers, ambulatory behavioral health and substance abuse clinics, physical therapy and rehabilitation centers, and dental practices. bioaerosol. an airborne dispersion of particles containing whole or parts of biological entities, including bacteria, viruses, dust mites, fungal hyphae, and fungal spores. such aerosols usually consist of a mixture of monodispersed and aggregate cells, spores, or viruses carried by other materials, such as respiratory secretions and/or inert particles. infectious bioaerosols (ie, those containing biological agents capable of causing an infectious disease) can be generated from human sources (eg, expulsion from the respiratory tract during coughing, sneezing, talking, singing, suctioning, or wound irrigation), wet environmental sources (eg, high-volume air consitioning and cooling tower water with legionella) or dry sources (eg, construction dust with spores produced by aspergillus spp). bioaerosols include large respiratory droplets and small droplet nuclei (cole ec. ajic 1998; 26: 453-64) . caregiver.. any person who is not an employee of an organization, is not paid, and provides or assists in providing health care to a patient (eg, family member, friend) and acquire technical training as needed based on the tasks that must be performed. cohorting. in the context of this guideline, this term applies to the practice of grouping patients infected or colonized with the same infectious agent together to confine their care to one area and prevent contact with susceptible patients (cohorting patients). during outbreaks, health care personnel may be assigned to a cohort of patients to further limit opportunities for transmission (cohorting staff). colonization. proliferation of microorganisms on or within body sites without detectable host immune response, cellular damage, or clinical expression. the presence of a microorganism within a host may occur with varying durations but may become a source of potential transmission. in many instances, colonization and carriage are synonymous. droplet nuclei. microscopic particles , 5 mm in size that are the residue of evaporated droplets and are produced when a person coughs, sneezes, shouts, or sings. these particles can remain suspended in the air for prolonged periods and can be carried on normal air currents in a room or beyond, to adjacent spaces or areas receiving exhaust air. engineering controls. removal or isolation of a workplace hazard through technology. an airborne infection isolation room, a protective environment, engineered sharps injury prevention device, and a sharps container are examples of engineering controls. epidemiologically important pathogen. an infectious agent that has one or more of the following characteristics: (1) readily transmissible, (2) a proclivity toward causing outbreaks, (3) possible association with a severe outcome, and (4) difficult to treat. examples include acinetobacter spp, aspergillus spp, burkholderia cepacia, clostridium difficile, klebsiella or enterobacter spp, extended-spectrum beta-lactamaseproducing gram-negative bacilli, methicillin-resistant staphylococcus aureus, pseudomonas aeruginosa, vancomycin-resistant enterococci, vancomycin-resistant staphylococcus aureus, influenza virus, respiratory syncytial virus, rotavirus, severe acute respiratory syndrome coronavirus, noroviruses, and the hemorrhagic fever viruses. hand hygiene. a general term that applies to any one of the following: (1) handwashing with plain (nonantimicrobial) soap and water, (2) antiseptic handwashing (soap containing antiseptic agents and water), (3) antiseptic handrub (waterless antiseptic product, most often alcohol-based, rubbed on all surfaces of hands), or (4) surgical hand antisepsis (antiseptic handwash or antiseptic handrub performed preoperatively by surgical personnel to eliminate transient hand flora and reduce resident hand flora). 558 health care-associated infection (hai). an infection that develops in a patient who is cared for in any setting where health care is delivered (eg, acute care hospital, chronic care facility, ambulatory clinic, dialysis center, surgicenter, home) and is related to receiving health care (ie, was not incubating or present at the time health care was provided). in ambulatory and home settings, hai refers to any infection that is associated with a medical or surgical intervention. because the geographic location of infection acquisition is often uncertain, the preferred term is considered to be health care-associated rather than health care-acquired. healthcare epidemiologist. a person whose primary training is medical (md, do) and/or masters-or doctorate-level epidemiology who has received advanced training in health care epidemiology. typically these professionals direct or provide consultation to an infection control program in a hospital, long-term care facility, or health care delivery system (also see infection control professional). health care personnel, health care worker (hcw). any paid or unpaid person who works in a health care setting (eg, any person who has professional or technical training in a health care-related field and provides patient care in a health care setting or any person who provides services that support the delivery of health care such as dietary, housekeeping, engineering, maintenance personnel). hematopoietic stem cell transplantation (hsct). any transplantation of blood-or bone marrow-derived hematopoietic stem cells, regardless of donor type (eg, allogeneic or autologous) or cell source (eg, bone marrow, peripheral blood, or placental/umbilical cord blood), associated with periods of severe immunosuppression that vary with the source of the cells, the intensity of chemotherapy required, and the presence of graft versus host disease (mmwr 2000; 49: rr-10). high-efficiency particulate air (hepa) filter. an air filter that removes .99.97% of particles . 0.3 mm (the most penetrating particle size) at a specified flow rate of air. hepa filters may be integrated into the central air handling systems, installed at the point of use above the ceiling of a room, or used as portable units (mmwr 2003; 52: rr-10). home care. a wide range of medical, nursing, rehabilitation, hospice, and social services delivered to patients in their place of residence (eg, private residence, senior living center, assisted living facility). home health care services include care provided by home health aides and skilled nurses, respiratory therapists, dieticians, physicians, chaplains, and volunteers; provision of durable medical equipment; home infusion therapy; and physical, speech, and occupational therapy. immunocompromised patient. a patient whose immune mechanisms are deficient because of a congenital or acquired immunologic disorder (eg, human immunodeficiency virus infection, congenital immune deficiency syndromes), chronic diseases such as diabetes mellitus, cancer, emphysema, or cardiac failure, intensive care unit care, malnutrition, and immunosuppressive therapy of another disease process [eg, radiation, cytotoxic chemotherapy, anti-graft rejection medication, corticosteroids, monoclonal antibodies directed against a specific component of the immune system]). the type of infections for which an immunocompromised patient has increased susceptibility is determined by the severity of immunosuppression and the specific component(s) of the immune system that is affected. patients undergoing allogeneic hematopoietic stem cell transplantation and those with chronic graft versus host disease are considered the most vulnerable to health care-associated infections. immunocompromised states also make it more difficult to diagnose certain infections (eg, tuberculosis) and are associated with more severe clinical disease states than persons with the same infection and a normal immune system. infection. the transmission of microorganisms into a host after evading or overcoming defense mechanisms, resulting in the organism's proliferation and invasion within host tissue(s). host responses to infection may include clinical symptoms or may be subclinical, with manifestations of disease mediated by direct organisms pathogenesis and/or a function of cell-mediated or antibody responses that result in the destruction of host tissues. infection control and prevention professional (icp). a person whose primary training is in either nursing, medical technology, microbiology, or epidemiology and who has acquired specialized training in infection control. responsibilities may include collection, analysis, and feedback of infection data and trends to health care providers; consultation on infection risk assessment, prevention, and control strategies; performance of education and training activities; implementation of evidence-based infection control practices or those mandated by regulatory and licensing agencies; application of epidemiologic principles to improve patient outcomes; participation in planning renovation and construction projects (eg, to ensure appropriate containment of construction dust); evaluation of new products or procedures on patient outcomes; oversight of employee health services related to infection prevention; implementation of preparedness plans; communication within the health care setting, with local and state health departments, and with the community at large concerning infection control issues; and participation in research. certification in infection control is available through the certification board of infection control and epidemiology. infection control and prevention program. a multidisciplinary program that includes a group of activities to ensure that recommended practices for the prevention of health care-associated infections are implemented and followed by health care workers, making the health care setting safe from infection for patients and health care personnel. the joint commission on accreditation of healthcare organizations requires the following 5 components of an infection control program for accreditation: (1) surveillance: monitoring patients and health care personnel for acquisition of infection and/or colonization; (2) investigation: identification and analysis of infection problems or undesirable trends; (3) prevention: implementation of measures to prevent transmission of infectious agents and to reduce risks for device-and procedure-related infections; (4) control: evaluation and management of outbreaks; and (5) reporting: provision of information to external agencies as required by state and federal laws and regulations (see http://www.jcaho.org). the infection control program staff has the ultimate authority to determine infection control policies for a health care organization with the approval of the organization's governing body. long-term care facility (ltcf). a residential or outpatient facility designed to meet the biopsychosocial needs of persons with sustained self-care deficits. these include skilled nursing facilities, chronic disease hospitals, nursing homes, foster and group homes, institutions for the developmentally disabled, residential care facilities, assisted living facilities, retirement homes, adult day health care facilities, rehabilitation centers, and long-term psychiatric hospitals. mask. a term that applies collectively to items used to cover the nose and mouth and includes both procedure masks and surgical masks (see http://www.fda. gov/cdrh/ode/guidance/094.html#4). multidrug-resistant organism (mdro). in general, a bacterium (excluding mycobacterium tuberculosis) that is resistant to 1 or more classes of antimicrobial agents and usually is resistant to all but 1 or 2 commercially available antimicrobial agents (eg, methicillin-resistant staphylococcus aureus, vancomycin-resistant enterococci, extended-spectrum beta-lactamase-producing or intrinsically resistant gram-negative bacilli). 176 nosocomial infection. derived from 2 greek words, ''nosos'' (disease) and ''komeion'' (to take care of), refers to any infection that develops during or as a result of an admission to an acute care facility (hospital) and was not incubating at the time of admission. personal protective equipment (ppe). a variety of barriers used alone or in combination to protect mucous membranes, skin, and clothing from contact with infectious agents. ppe includes gloves, masks, respirators, goggles, face shields, and gowns. procedure mask. a covering for the nose and mouth that is intended for use in general patient care situations. these masks generally attach to the face with ear loops rather than ties or elastic. unlike surgical masks, procedure masks are not regulated by the food and drug administration. protective environment. a specialized patient care area, usually in a hospital, with a positive air flow relative to the corridor (ie, air flows from the room to the outside adjacent space). the combination of high-efficiency particulate air filtration, high numbers (.12) of air changes per hour, and minimal leakage of air into the room creates an environment that can safely accommodate patients with a severely compromised immune system (eg, those who have received allogeneic hemopoietic stem cell transplantation) and decrease the risk of exposure to spores produced by environmental fungi. other components include use of scrubbable surfaces instead of materials such as upholstery or carpeting, cleaning to prevent dust accumulation, and prohibition of fresh flowers or potted plants. quasi-experimental study. a study undertaken to evaluate interventions but do not use randomization as part of the study design. these studies are also referred to as nonrandomized, pre-/postintervention study designs. these studies aim to demonstrate causality between an intervention and an outcome but cannot achieve the level of confidence concerning an attributable benefit obtained through a randomized controlled trial. in hospitals and public health settings, randomized control trials often cannot be implemented due to ethical, practical, and urgency reasons; therefore, quasi-experimental design studies are commonly used. however, even if an intervention appears to be effective statistically, the question can be raised as to the possibility of alternative explanations for the result. such a study design is used when it is not logistically feasible or ethically possible to conduct a randomized controlled trial, (eg, during outbreaks). within the classification of quasi-experimental study designs, there is a hierarchy of design features that may contribute to validity of results (harris et al. cid 2004 :38: 1586 . residential care setting. a facility in which people live, minimal medical care is delivered, and the psychosocial needs of the residents are provided for. respirator. a personal protective device worn by health care personnel over the nose and mouth to protect them from acquiring airborne infectious diseases due to inhalation of infectious airborne particles , 5 mm in size. these include infectious droplet nuclei from patients with mycobacterium tuberculosis, variola virus [smallpox], or severe acute respiratory syndrome and dust particles that contain infectious particles, such as spores of environmental fungi (eg, aspergillus spp). the centers for disease control and prevention's national institute for occupational safety and health (niosh) certifies respirators used in health care settings (see http://www.cdc.gov/niosh/topics/respirators/). the n95 disposable particulate, air-purifying respirator is the type used most commonly by health care personnel. other respirators used include n-99 and n-100 particulate respirators, powered air-purifying respirators with high-efficiency filters, and nonpowered fullfacepiece elastomeric negative pressure respirators. a listing of niosh-approved respirators can be found at http://www.cdc.gov/niosh/npptl/respirators/disp_part/ particlist.html. respirators must be used in conjunction with a complete respiratory protection program, as required by the occupational safety and health administration, which includes fit testing, training, proper selection of respirators, medical clearance, and respirator maintenance. respiratory hygiene/cough etiquette. a combination of measures designed to minimize the transmission of respiratory pathogens through droplet or airborne routes in health care settings. the components of respiratory hygiene/cough etiquette are (1) covering the mouth and nose during coughing and sneezing, (2) using tissues to contain respiratory secretions with prompt disposal into a no-touch receptacle, (3) offering a surgical mask to persons who are coughing to decrease contamination of the surrounding environment, and (4) turning the head away from others and maintaining spatial separation (ideally .3 feet) when coughing. these measures are targeted to all patients with symptoms of respiratory infection and their accompanying family members or friends beginning at the point of initial encounter with a health care setting (eg, reception/triage in emergency departments, ambulatory clinics, health care provider offices). 126 (srinivasin a iche 2004; 25: 1020; http://www.cdc.gov/flu/ professionals/infectioncontrol/resphygiene.htm). safety culture. shared perceptions of workers and management regarding the level of safety in the work environment. a hospital safety climate includes the following organizational components: (1) senior management support for safety programs, (2) absence of workplace barriers to safe work practices, (3) cleanliness and orderliness of the worksite, (4) minimal conflict and good communication among staff members, (5) frequent safety-related feedback/training by supervisors, and (6) availability of ppe and engineering controls. 618 source control. the process of containing an infectious agent either at the portal of exit from the body or within a confined space. the term is applied most frequently to containment of infectious agents transmitted by the respiratory route but could apply to other routes of transmission, (eg, a draining wound, vesicular or bullous skin lesions). respiratory hygiene/cough etiquette that encourages individuals to ''cover your cough'' and/or wear a mask is a source control measure. the use of enclosing devices for local exhaust ventilation (eg, booths for sputum induction or administration of aerosolized medication) is another example of source control. standard precautions. a group of infection prevention practices that apply to all patients, regardless of suspected or confirmed diagnosis or presumed infection status. standard precautions represents a combination and expansion of universal precautions 778 and body substance isolation. 1109 standard precautions are based on the principle that all blood, body fluids, secretions, excretions except sweat, nonintact skin, and mucous membranes may contain transmissible infectious agents. standard precautions include hand hygiene and, depending on the anticipated exposure, use of gloves, gown, mask, eye protection, or face shield. in addition, equipment or items in the patient environment likely to have been contaminated with infectious fluids must be handled in a manner to prevent transmission of infectious agents (eg, wear gloves for handling, contain heavily soiled equipment, properly clean and disinfect or sterilize reusable equipment before use on another patient). surgical mask. a device worn over the mouth and nose by operating room personnel during surgical procedures to protect both surgical patients and operating room personnel from transfer of microorganisms and body fluids. surgical masks also are used to protect health care personnel from contact with large infectious droplets (. 5 mm in size). according to draft guidance issued by the food and drug administration on may 15, 2003 , surgical masks are evaluated using standardized testing procedures for fluid resistance, bacterial filtration efficiency, differential pressure (air exchange), and flammability to mitigate the risks to health associated with the use of surgical masks. these specifications apply to any masks that are labeled surgical, laser, isolation, or dental or medical procedure (http://www.fda.gov/cdrh/ode/guidance/094.html#4). surgical masks do not protect against inhalation of small particles or droplet nuclei and should not be confused with particulate respirators that are recommended for protection against selected airborne infectious agents (eg, mycobacterium tuberculosis). other species s use contact precautions for diapered or incontinent persons for the duration of illness or to control institutional outbreaks. giardia lamblia s use contact precautions for diapered or incontinent persons for the duration of illness or to control institutional outbreaks. noroviruses s use contact precautions for diapered or incontinent persons for the duration of illness or to control institutional outbreaks. persons who clean areas heavily contaminated with feces or vomitus may benefit from wearing masks, because virus can be aerosolized from these body substances; 142,147,148 ensure consistent environmental cleaning and disinfection with focus on restrooms even when apparently unsoiled. 272, 1060 hypochlorite solutions may be required when there is continued transmission. [289] [290] [291] alcohol is less active, but there is no evidence that alcohol antiseptic handrubs are not effective for hand decontamination. 293 cohorting of affected patients to separate airs paces and toilet facilities may help interrupt transmission during outbreaks. rotavirus c di ensure consistent environmental cleaning and disinfection and frequent removal of soiled diapers. prolonged shedding may occur in both immunocompetent and immunocompromised children and the elderly. 930 also for asymptomatic, exposed infants delivered vaginally or by c-section and if mother has active infection and membranes have been ruptured for more than 4 to 6 hours until infant surface cultures obtained at 24 to 36 hours of age negative after 48 hours of incubation. 1065 susceptible hcws should not enter room if immune caregivers are available; no recommendation for face protection of immune hcws; no recommendation for type of protection (ie, surgical mask or respirator) for susceptible hcws. in an immunocompromised host with varicella pneumonia, prolong the duration of precautions for duration of illness. postexposure prophylaxis: provide postexposure vaccine as soon as possible but within 120 hours; for susceptible exposed persons for whom vaccine is contraindicated (immunocompromised persons, pregnant women, newborns whose mother's varicella onset is # 5 days before delivery or within 48 hours after delivery) provide vzig, when available, within 96 hours; if unavailable, use ivig. provide airborne precautions for exposed susceptible persons and exclude exposed susceptible health care workers beginning 8 days after first exposure until 21 days after last exposure or 28 if received vzig, regardless of postexposure vaccination. 1032 variola (see smallpox) vibrio parahaemolyticus (see gastroenteritis) vincent's angina (trench mouth) s viral hemorrhagic fevers due to lassa, ebola, marburg, crimean-congo fever viruses s, d, c di single-patient room preferred. emphasize: use of sharps safety devices and safe work practices, hand hygiene; barrier protection against blood and body fluids on entry into room (single gloves and fluid-resistant or impermeable gown, face/eye protection with masks, goggles or face shields), and appropriate waste handling. use n95 or higher-level respirator when performing aerosol-generating procedures. largest viral load in final stages of illness when hemorrhage may occur; additional ppe, including double gloves, leg and shoe coverings may be used, especially in resource-limited settings where options for cleaning and laundry are limited. notify public health officials immediately if ebola is suspected. 212, 313, 738, 770 also see table 3 *type of precautions: a, airborne precautions; c, contact; d, droplet; s, standard; when a, c, and d are specified, also use s. y duration of precautions: cn, until off antimicrobial treatment and culture-negative; di, duration of illness (with wound lesions, di means until wounds stop draining); 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methicillin-resistant staphylococcus aureus contamination bacterial contamination on the surface of hospital linen chutes designing linen chutes to reduce spread of infectious organisms iatrogenic contamination of multidose vials in simulated use: a reassessment of current patient injection technique a large outbreak of hepatitis b virus infections associated with frequent injections at a physician's office a large nosocomial outbreak of hepatitis c and hepatitis b among patients receiving pain remediation treatments patient-to-patient transmission of hepatitis c virus through the use of multidose vials during general anesthesia an outbreak of hepatitis c virus infections among outpatients at a hematology/oncology clinic streptococcal meningitis following myelogram procedures a prospective study to determine whether cover gowns in addition to gloves decrease nosocomial transmission of vancomycin-resistant enterococci in an intensive care unit parainfluenza virus infections after hematopoietic stem cell transplantation: risk factors, response to antiviral therapy, and effect on transplant outcome parainfluenza virus 3 infection after stem cell transplant: relevance to outcome of rapid diagnosis and ribavirin treatment serial observations of chronic rotavirus infection in an immunodeficient child an outbreak of imipenem-resistant acinetobacter baumannii in critically ill surgical patients epidemiology of methicillin-resistant staphylococcus aureus at a university hospital in the canary islands nosocomial acquisition of methicillin-resistant staphylococcus aureus during an outbreak of severe acute respiratory syndrome increase in methicillin-resistant staphylococcus aureus acquisition rate and change in pathogen pattern associated with an outbreak of severe acute respiratory syndrome an outbreak of mupirocin-resistant staphylococcus aureus on a dermatology ward associated with an environmental reservoir risk of secondary meningococcal disease in health-care workers an outbreak of measles at an international sporting event with airborne transmission in a domed stadium an outbreak of airborne nosocomial varicella herpes zoster causing varicella (chickenpox) in hospital employees: cost of a casual attitude identification of factors that disrupt negative air pressurization of respiratory isolation rooms an evaluation of hospital special ventilation room pressures nosocomial transmission of tuberculosis associated with a draining abscess an outbreak of tuberculosis among hospital personnel caring for a patient with a skin ulcer secondary measles vaccine failure in healthcare workers exposed to infected patients a cluster of primary varicella cases among healthcare workers with false-positive varicella zoster virus titers airborne transmission of nosocomial varicella from localized zoster zoster-causing varicella: current dangers of contagion without isolation detection of aerosolized varicella-zoster virus dna in patients with localized herpes zoster measles vaccination after exposure to natural measles use of live measles virus vaccine to abort an expected outbreak of measles within a closed population measles, mumps, and rubella vaccine use and strategies for elimination of measles, rubella, and congenital rubella syndrome and control of mumps: recommendations of the advisory committee on immunization practices (acip) general recommendations on immunization: recommendations of the advisory committee on immunization practices (acip) postexposure effectiveness of varicella vaccine postexposure varicella vaccination in siblings of children with active varicella centers for disease control and preverntion. vaccinia (smallpox) vaccine: recommendations of the advisory committee on immunization practices (acip) smallpox vaccination: a review. part i: background, vaccination technique, normal vaccination and revaccination, and expected normal reactions smallpox in tripolitania, 1946: an epidemiological and clinical study of 500 cases, including trials of penicillin treatment ventilation for protection of immune-compromised patients efficacy of portable filtration units in reducing aerosolized particles in the size range of mycobacterium tuberculosis dolin r, editors. mandell, douglas and bennett's principles and practice of infectious diseases control of communicable diseases manual outbreak of amebiasis in a family in the netherlands parasitic disease control in a residential facility for the mentally retarded: failure of selected isolation procedures west nile virus: epidemiology, clinical presentation, diagnosis, and prevention person-to-person transmission of brucella melitensis isolation of brucella melitensis from human sperm prevention of laboratoryacquired brucellosis chlamydia pneumoniae as a new source of infectious outbreaks in nursing homes an epidemic of infections due to chlamydia pneumoniae in military conscripts an outbreak of surgical wound infections due to clostridium perfringens acquisition of coccidioidomycosis at necropsy by inhalation of coccidioidal endospores donor-related coccidioidomycosis in organ transplant recipients centers for disease control and prevention. acute hemorrhagic conjunctivitis outbreak caused by coxsackievirus a24 outbreak of adenovirus type 30 in a neonatal intensive care unit an outbreak of epidemic keratoconjunctivtis in a pediatric unit due to adenovirus type 8 a large outbreak of epidemic keratoconjunctivitis: problems in controlling nosocomial spread nosocomial transmission of cryptococcosis cryptococcal endophthalmitis after corneal transplantation probable transmission of norovirus on an airplane centers for disease control and prevention. prevention of hepatitis a through active or passive immunization: recommendations of the advisory committee on immunization practices (acip) hepatitis a outbreak in a neonatal intensive care unit: risk factors for transmission and evidence of prolonged viral excretion among preterm infants excretion of hepatitis a virus in the stools of hospitalized hepatitis patients hospital outbreak of hepatitis e herpes simplex virus infections neonatal herpes infection: diagnosis, treatment and prevention human metapneumovirus infection in the united states: clinical manifestations associated with a newly emerging respiratory infection in children listeria moncytogenes cross-contamination in a nursery neonatal listeriosis due to cross-infection confirmed by isoenzyme typing and dna fingerprinting outbreak of neonatal listeriosis associated with mineral oil neonatal cross-infection with listeria monocytogenes nosocomial malaria and saline flush plasmodium falciparum malaria transmitted in hospital through heparin locks nosocomial malaria from contamination of a multidose heparin container with blood hospital-acquired malaria transmitted by contaminated gloves clustering of necrotizing enterocolitis: interruption by infection-control measures how contagious is necrotizing enterocolitis? an outbreak of rotavirus-associated neonatal necrotizing enterocolitis increased risk of illness among nursery staff caring for neonates with necrotizing enterocolitis outbreak of adenovirus 35 pneumonia among adult residents and staff of a chronic care psychiatric facility nosocomial adenovirus infection: molecular epidemiology of an outbreak a recent outbreak of adenovirus type 7 infection in a chronic inpatient facility for the severely handicapped an outbreak of multidrugresistant pneumococcal pneumonia and bacteremia among unvaccinated nursing home residents human-to-human transmission of rabies virus by corneal transplant human rabies prevention, united states, 1999: recommendations of the advisory committee on immunization practices (acip) rhinovirus and the lower respiratory tract concurrent outbreaks of rhinovirus and respiratory syncytial virus in an intensive care nursery: epidemiology and associated risk factors rhinovirus infection associated with serious lower respiratory illness in patients with bronchopulmonary dysplasia nosocomial ringworm in a neonatal intensive care unit: a nurse and her cat nosocomial transmission of trichophyton tonsurans tinea corporis in a rehabilitation hospital molecular epidemiology of staphylococcal scalded skin syndrome in premature infants an outbreak of fatal nosocomial infections due to group a streptococcus on a medical ward an outbreak of group a streptococcal infection among health care workers clusters of invasive group a streptococcal infections in family, hospital, and nursing home settings isolation techniques for use in hospitals us government printing office rethinking the role of isolation practices in the prevention of nosocomial infections the authors and hicpac gratefully acknowledge dr larry strausbaugh for his many contributions and valued guidance in the preparation of this guideline. the mode(s) and risk of transmission for each specific disease agent listed in this appendix were reviewed. principle sources consulted for the development of disease-specific recommendations for the appendix included infectious disease manuals and textbooks. 831, 1039, 1040 the published literature was searched for evidence of person-to-person transmission in health care and non-health care settings with a focus on reported outbreaks that would assist in developing recommendations for all settings where health care is delivered. the following criteria were used to assign transmission-based precautions categories: d a transmission-based precautions category was assigned if there was strong evidence for person-to-person transmission via droplet, contact, or airborne routes in health care or non-health care settings and/or if patient factors (eg, diapered infants, diarrhea, draining wounds) increased the risk of transmission. d transmission-based precautions category assignments reflect the predominant mode(s) of transmission. d if there was no evidence for person-to-person transmission by droplet, contact or airborne routes, then standard precautions were assigned. d if there was a low risk for person-to-person transmission and no evidence of health care-associated transmission, then standard precautions were assigned. d standard precautions were assigned for bloodborne pathogens (eg, hbv, hcv, hiv) in accordance with cdc recommendations for universal precautions issued in 1988. 778 subsequent experience has confirmed the efficacy of standard precautions to prevent exposure to infected blood and body fluid. 776, 777, 863 additional information relevant to use of precautions was added in the comments column to assist the caregiver in decision-making. citations were added as needed to support a change in or provide additional evidence for recommendations for a specific disease and for new infectious agents (eg, sars-cov, avian influenza) that have been added to appendix a. the reader may refer to more detailed discussion concerning modes of transmission and emerging pathogens in the background text and for mdro control in the mdro guideline. 