key: cord-266261-6h7c26xg authors: bharati, joyita; ramachandran, raja; kumar, vivek; kohli, harbir singh title: covid‐19 pandemic in limited‐resource countries: strategies for challenges in a dialysis unit date: 2020-07-12 journal: nephrology (carlton) doi: 10.1111/nep.13748 sha: doc_id: 266261 cord_uid: 6h7c26xg nan south and south-east asian countries are densely populated regions with inadequate health-care infrastructure. the rapid surge of novel coronavirus disease 2019 (covid-19) pandemic has brought unique challenges. we describe our solutions for these challenges in a limited-resource setting. our unit is a tertiary referral centre with 30 haemodialysis stations. in addition to stable patients, around 10 cases of advanced renal failure with symptoms camouflaging severe acute respiratory illness are admitted daily. in the absence of universal testing, apprehensions related to inadvertent exposure to covid-19 positive patient was increasing among health-care workers (hcw) and patients, which was crucial to be addressed to maintain functionality of the unit. a risk stratification algorithm after inadvertent exposure to covid-19 positive patient was adapted from the u.s. centers for disease control and prevention (cdc) to educate hcw. 1,2 a flow-chart simplified the interpretation of cdc tables for risk stratification which were found intricate by hcw. hcw were asked to lead, screen patients and discuss to ensure confidence building and transparency. inculcation of "leadership quality" to frontline dialysis hcw constantly motivated them to function without any fear. universal masking, hand hygiene and separation of adjacent dialysis stations by 2 m was done. 1 of the two operating rooms, one was converted to covid isolation room. creation of a proper doffing area was consequential to sacrificing one of the two waiting areas. they were in proximity to each other. protocol for hemodialysis unit during covid-19 pandemic. pgimer covid-19 portal guidance for risk assessment and public health management of healthcare personnel with potential exposure in a healthcare setting to patients with coronavirus disease the authors declare no conflicts of interest. key: cord-028273-22swinc6 authors: cabrini, luca; grasselli, giacomo; cecconi, maurizio title: yesterday heroes, today plague doctors: the dark side of celebration date: 2020-07-01 journal: intensive care med doi: 10.1007/s00134-020-06166-4 sha: doc_id: 28273 cord_uid: 22swinc6 nan and have even suffered physical assault. in the philippines, the president ordered the police protection for hcws [4] . the coordinating center of the "covid-19 lombardy icu-network", therefore, promoted an exploratory survey to assess the incidence of episodes of discrimination experienced by specialists and trainees in anesthesiology and in intensive care medicine. a survey comprised of 6 questions was distributed among the 72 icus of the regional network. we received 627 completed surveys; 18% of the responders were trainees. overall, 159 hcws (25%) reported at least 1 episode of discrimination involving themselves, their colleagues or family members. among these, 11.3% reported more than 10 episodes of discrimination a description of the worst episode was allowed: 60 events were described. most common were: ostracizing of hcws or their family members by neighbors and friends; refusal to assist hcws in their daily needs (e.g. shopping) and difficulty in recruitment of babysitters or caregivers. notably, five cases of vandalism and physical assault were reported, that in two cases also required police intervention. sadly, the "not in my backyard" principle seems to apply to hcws, who are celebrated as long as they stay confined in hospitals, and this discrimination is also being extended to their families. healthcare systems administrators and policy-makers should employ every means to minimize the risk of infection among hcws by providing adequate ppe and training. at the same time, informative campaigns should place the risk of contagion from hcws in the right perspective. there is a good chance that as long as we are presented as heroes continuously facing death, we will suffer discrimination; such portrayal erroneously belabours the risk of being infected by hcws, making it seem a very probable option. people must be confident that hcws are taking every precaution to avoid infecting themselves and others, and that these precautions baseline characteristics and outcomes of 1591 patients infected with sars-cov-2 admitted to icus of the lombardy region part of the cure or am i part of the disease? keeping coronavirus out when a doctor comes home springer nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.accepted: 24 june 2020 key: cord-252250-hhdawwjf authors: menon, vikas; padhy, susanta kumar title: ethical dilemmas faced by health care workers during covid-19 pandemic: issues, implications and suggestions date: 2020-04-28 journal: asian j psychiatr doi: 10.1016/j.ajp.2020.102116 sha: doc_id: 252250 cord_uid: hhdawwjf nan the unexpected and unprecedented challenges brought on by the covid-19 pandemic has inflicted tremendous strain on health care resources, even in developed countries. the sheer magnitude of numbers coupled with high virulence of the infection has triggered country wide lockdowns across vast swathes of the globe. one group expected to work as usual in these trying times are health care workers and, therefore, the impact of covid-19 pandemic on the mental health of frontline health care workers is gaining legitimate attention (ayanian, 2020; lai et al., 2020) . in this regard, we point out a few moral and ethical dilemmas that can be faced by health care workers (hcw) while attending the call of duty: j o u r n a l p r e -p r o o f 2. dilemma 2 -should i retain ventilatory support for a critical patient who is unlikely to survive or use the ventilator for a less critical patient with better prognosis? as much as doctors are bound by the hippocratic oath that entrusts every doctor to treat all sick patients to the best of their abilities, in times such as these, triaging of finite resources is a pragmatic consideration. consequently, frontline hcw's may find themselves in an unpleasant situation where they have to make a choice of allocating scant resources for those who need them the most. adding a further layer of complexity to this issue are laws governing passive euthanasia in india, which state that a medical board constituted for the purpose by the hospital should first discuss the issue with family members and only after obtaining their written consent, proceed with withdrawal of ventilatory support. clearly, for an acute illness like covid 19, it is going to be an onerous task to convince emotionally charged family members about the limited chances of their loved one's survival and ask them to be 'altruistic' enough to spare the ventilator for another sick patient with better chances of survival. 3. dilemma 3 -if i have some respiratory symptoms and i think i may have been the above dilemmas, apart from being very personal, may also have larger ramifications for health care delivery. as these thoughts pre-occupy the mind, juxtaposed with other considerations such as looking after the needs of their families, their own physical and mental health care needs, as well as day to day demands of work and caregiving, judgment of hcw's may become clouded. this, in turn, may affect clinical decision, increase chances of medical errors and eventually increase the risk of burnout. we offer some suggestions to tackle the above scenarios: j o u r n a l p r e -p r o o f 1. institutions need to be upfront about their plans, policies and standard operating procedures to its staff and health care workers. availability of patient care, safety equipment and risk stratification protocols must be communicated clearly and updated on institutional websites. all health care workers should be briefed periodically about the rational use of ppe so that their safety concerns are addressed and at the same time, resources are utilized rationally. there must not be any attempt to paper over cracks; instead an open admission of possible shortcomings and steps taken to overcome them will allay anxieties and allow hcw's to mentally prepare themselves for challenges. as covid-19 duty is admittedly stressful, institutions may consider giving reduced shift hours (for instance, 4-6 hours) per work day to prevent burnout. 2. institutions must consider giving accommodation and quarantine facilities for its staff. if there are resource constraints, this facility must be made available at least to the hcw's during the period of covid duty as many of them may not feel comfortable going back to their families every day during the covid duty period. 3. pre-counselling of hcw before going to the frontline may help to allay concerns and provide opportunities for clarifying safety queries. the above mentioned ethical and moral dilemmas can be discussed beforehand so that hcw's are mentally prepared to handle such scenarios. involvement of mental health professionals at this stage would add value to the process by enabling utilization of their specific expertise in crisis counselling and problem-solving skills. 4. setting up of a covid support cell in every institution would serve as a one stop resource for mental and physical health care needs of hcw's. it also provides a forum for hcw, who may feel overwhelmed from time to time by the demands of caring, to discuss ongoing concerns and help to prevent burnout. as mentioned earlier, every hcw matters and their mental health often correlates with workplace productivity (duffield et al., 2014; kim et al., 2018) . health care team leaders should be trained to recognise signs of burnout among junior doctors as early identification and intervention is key (greenberg et al., 2020) . 5. ultimately, personal health is an individual responsibility. if an hcw has respiratory symptoms and does not wish to endanger others, the onus is on them to stay back and give a proper explanation for their decision. when in doubt, it is desirable to apply the ethical self-test as follows; "if my colleague at work had these symptoms, would i prefer him to come for duty?" setting out standard operating procedures for hcw's j o u r n a l p r e -p r o o f in this regard would remove ambiguity, facilitate individual decisions and lessen discrimination. extraordinary times call for extraordinary measures. we hope that the measures outlined above would assist institutions and team leaders in providing the best possible working conditions for their staff and health care workers. this will enable and motivate frontline health care workers to give their best while simultaneously preserving themselves for another day. financial disclosures: there are no financial disclosures or sources of support for the present work. the authors declare no conflicts of interest relevant to the contents of the manuscript. acknowledgments: none mental health needs of health care workers providing frontline covid-19 care a comparative review of nurse turnover rates and costs across countries managing mental health challenges faced by healthcare workers during covid-19 pandemic mental disorders among workers in the healthcare industry: 2014 national health insurance data factors associated with mental health outcomes among health care workers exposed to coronavirus disease key: cord-310508-zgqbfmzl authors: alavi-moghaddam, mostafa title: a novel coronavirus outbreak from wuhan city in china, rapid need for emergency departments preparedness and response; a letter to editor date: 2020-02-02 journal: arch acad emerg med doi: nan sha: doc_id: 310508 cord_uid: zgqbfmzl nan on 31 december 2019, chinese authorities reported the increase in incidence of severe pneumonia in wuhan city, hubei province of china. one week later, on january 7th, they confirmed that they had identified a new coronavirus, which is a family of microrna respiratory viruses including the common cold, and viruses such as severe acute respiratory syndrome (sars) and middle east respiratory syndrome (mers). this new virus was temporarily named "2019-ncov". wuhan city is a major international transport hub. this report to world health organization (who), raised global public health concern because this is the third coronavirus âȃşassociated acute respiratory illness outbreak. currently, up to the date of submitting this letter, 4593 cases of 2019-ncov infections have been confirmed globally, both in china (4537 have been confirmed, 976 of them presented with severe disease and 106 died) and outside of china (56 confirmed in 14 countries.). who risk assessment of 2019-ncov infection is very high in china and high in other countries (1). although 2019-ncov has not been included in the who blueprint list of priority diseases yet, mers cov, and sars -cov, which are already included in this list, are both coronaviruses that have led to global outbreaks in 2003 and 2012, respectively. the specific source and the exact primary mode of transmission of 2019-ncov to humans remain unknown. the clinical features and laboratory and radiological abnormalities with 2019-ncov infections are not specific and are similar to other respiratory tract infections. adults and pediatrics who ac-quire a 2019-ncov infection can show a spectrum of respiratory illness severity, from asymptomatic to mild, moderate or severe disease. the severe disease manifests as severe acute respiratory infection (sari) or severe pneumonia, acute respiratory distress syndrome (ards), sepsis and septic shock. patients with pre-existing medical comorbidities develop a more severe disease and have higher mortality rates compared to patients who do not have any comorbidity. clinical care of patients with suspected 2019-ncov should focus on early recognition, immediate isolation (separation), implementation of appropriate infection prevention and control (ipc) measures and provision optimized supportive care. at the triage of an emergency room, early recognition of suspected patients allows for timely initiation of ipc. 2019-ncov should be considered as a possible etiology of influenza like illness (ili) under certain situations according to case definitions of who (2) . both the health care worker (hcw) and the suspected case of acute respiratory illness (ali) should wear a medical mask and the patient should better be directed to a separate area, an isolation room if available. otherwise, keep a distance of at least one meter between suspected patients and other patients. instruct all suspected patients to cover their nose and mouth during coughing or sneezing with tissue or flexed elbows for protecting others. those with mild or moderate clinical presentations of the 2019-ncov infection may not require hospitalization, unless there is concern of rapid deterioration. all patients discharged to go home directly from fast track in emergency room should be instructed to consider ipc measures and to return hospital if their symptoms worsen (3). patients with severe illness, who are admitted to the emergency ward, should be transferred to the floor and if available to the icu ward as soon as possible. as long as they stay in emergency ward, they should be placed in single rooms or grouped together with those who have the same etiological or clinical diagnosis. limit patient movement within the center and ensure that patients wear medical masks when outside their rooms. hcw should perform hand hygiene after contact with respiratory secretions. droplet and contact precautions prevent direct or indirect transmission of the disease from contact with contaminated surfaces or equipment. hcw should use personal protective equipment (ppe) including medical mask, eye protection, gloves and gown, when entering the room and remove ppe when leaving. if equipment needs to be shared among patients, they should be cleaned and disinfected after each patient's use. hcw should apply airborne precautions when performing an aerosol generating procedure (i.e. open suctioning of respiratory tract, intubation, bronchoscopy, cardiopulmonary resuscitation) (4). hcw should immediately provide supplemental oxygen therapy for patients with sari and respiratory distress, hypoxemia or shock. oxygen therapy flow rate should be aimed at spo2>=90%, spo2>=92-95% and spo2>=94%, in non-pregnant, pregnant and children, respectively. hcw should recognize severe hypoxemic respiratory failure when a patient with respiratory distress is failing standard oxygen therapy. high-flow nasal oxygen (hfno) or non-invasive ventilation (niv) should be used in selected patients with hypoxemic respiratory failure. hypoxemic respiratory failure due to ards among these patients commonly results from intrapulmonary ventilation-perfusion mismatch or shunt and usually requires mechanical ventilation. thus, rapid sequence intubation should be performed using airborne precautions. implementation of mechanical ventilation using lower tidal volumes (4-8 ml/kg predicted body weight) and higher positive end-expiratory pressure (peep) is suggested. patients with sari should be treated cautiously with intravenous fluids when there is no evidence of shock, because aggressive fluid resuscitation may worsen oxygenation. for resuscitation of septic shock in adults, at least 30 ml/kg of isotonic crystalloid should be infused in the first 3 hours of shock identification and in children rapid bolus of 20 ml/kg as loading dose and up to 40-60 ml/kg of isotonic crystalloid infusion in the first hour of shock identification is needed. vasopressor should be administered when shock persists during or after fluid resuscitation. if signs of poor perfusion persist despite reaching mean arterial pressure (map) target (i.e. >65 mmhg) with fluids and vasopressor, consider administering an inotrope such as dobutamine. empiric antimicrobials should be initiated within one hour of identification of sepsis to treat all likely pathogens causing sari. empiric antibiotic treatment should be based on the clinical diagnosis of severe pneumonia or sepsis, local epidemi-ology and susceptibility data as well as treatment guidelines. if influenza is also a concern and there is a local circulation of influenza virus, a neuraminidase inhibitor should be adjoined to empiric therapy. empiric antibiotic therapy should be de-escalated on the basis of microbiology results and clinical judgment. systemic corticosteroids should not be routinely adding to therapy unless indicated for another reason. collection of clinical specimens for laboratory diagnosis is suggested in early outbreak period and after that it is only advised for investigational purposes. if laboratory diagnosis is considered, serology is recommended only when rt-pcr is not available. otherwise, hcw should collect specimens from both the upper respiratory tract and lower respiratory tract for testing 2019-ncov via rt-pcr (5). at the time being, emergency preparedness and response for providing appropriate care to the patients suspected to coronavirus-associated acute respiratory illness (abovementioned plans) should be developed and implemented in the emergency departments, as the frontline of treating human infections of 2019-ncov in the hospitals. none. none. organization wh. novel coronavirus (2019-ncov) situation report-9 surveillance case definitions for human infection with novel coronavirus ( ncov): interim guidance v1 novel coronavirus (2019-ncov) advice for the public: interim guidance. world health organization infection prevention and control during health care when novel coronavirus ( ncov) infection is suspected: interim guidance clinical management of severe acute respiratory infection when novel coronavirus (2019-ncov) infection is suspected: interim guidance key: cord-311539-pbzb0jjt authors: puro, v.; girardi, e.; daglio, m.; simonini, g.; squarcione, s.; ippolito, g. title: clustered cases of pneumonia among healthcare workers over a 1-year period in three italian hospitals: applying the who sars alert date: 2006 journal: infection doi: 10.1007/s15010-006-5604-8 sha: doc_id: 311539 cord_uid: pbzb0jjt background: the world health organization (who) has recommended that a severe acute respiratory syndrome (sars) alert should be raised when two or more healthcare workers (hcw) in the same health care unit fulfil the sars clinical criteria, with onset of illness in the same 10-day period. however, in a number of european countries (including italy) data on reasons for sickness absence are not routinely collected within current hcw worker sickness reporting systems, because of concerns about privacy. to help plan for the implementation of the proposed alert system in italy, we aimed to determine the minimum number of alert cases defining a cluster. patients and methods: sickness absences longer than 7 days in hcw employed in three hospitals in 2003, were identified by checking the hospitals’ administrative databases. hcw with onset of illness in the same 10-day period were contacted and asked whether they have been diagnosed with pneumonia. results: overall, 273 absences > 7 days were recorded and 36 clusters of at least two absences > 7 days were identified; a total of 94 hcw were involved in these clusters. only two hcw involved in different clusters, reported pneumonia. conclusion: the occurrence of clusters of two or more cases of pneumonia in hcw in the same hospital unit appears to be an uncommon event, and thus the alert system proposed is not likely to result in large numbers of false positive alerts. however, it may be difficult to implement this alert system in countries where clinical data on sickness absences are not routinely collected, and alternative mechanisms should be considered. to detect the possible re-emergence of severe acute respiratory syndrome (sars), the world health organization (who) has recommended the implementation of an alert system based on the surveillance of healthcare workers (hcw): an alert should be raised when two or more hcw in the same health care unit fulfil the clinical criteria for sars, with onset of illness in the same 10-day period [1] . moreover, the who recommends that before implementing the proposed alert system, a jurisdiction may determine, based on national sars risk assessment and local experience of acute respiratory diseases, the minimum number of alert cases defining an alert cluster. however, in italy, and in a number of other european countries data on the reason for sickness absence are not collected within current hcw worker sickness reporting systems, because of concerns about privacy and confidentiality [2] . thus, national or local data that would allow an assessment of the specificity of the proposed definition of an alert cluster, or an estimate of the number of alerts that would occur in the absence of a re-emergence of sars, are not available. to try to determine the minimum number of pneumonia alert cases that should define a sars alert cluster in italy, we analyzed sickness absences longer than 7 days, which occurred among hcw employed in three italian hospitals in 2003. three italian hospitals voluntarily participated in the study. hospital a is an infectious diseases research hospital with 180 beds, including 20 dedicated to respiratory infections. hospital b is a university hospital with 400 beds, 60 of which are dedicated to infectious diseases. hospital c is a general urban hospital with 600 beds, including 16 in an infectious disease ward and 25 in the respiratory medicine unit. the study population was limited to hcw working in adult medical wards, emergency departments, admission units, and intensive care units. we assumed that a case of pneumonia would result in more than 7 days of sickness absence. we checked the hospitals' administrative database to extract clusters of two or more cases of absences > 7 days in hcw assigned to the same unit and with dates of onset of illness in the same 10-day period. all the hcw identified as being part of a cluster were then contacted by their occupational health physician, who informed them about the aims of the study, assured them that participation was wholly voluntary, and asked them to consent to a partial disclosure of the reason for their absence, i.e. whether at the time of the absence, they had been diagnosed with pneumonia. in hospital c, all hcw with absences > 7 days were asked if they had had pneumonia, an influenza-like illness, or another respiratory tract illness, regardless of whether or not they were part of a cluster. during the study period a total of 2,035 hcw were employed in the hospital units involved in the study (table 1) . overall, 273 absences > 7 days were recorded, and 36 clusters of at least 2 absences were identified. a total of 94 hcw were involved in these clusters; all but two consented to participate in the study. only two hcw from different centres reported they had been given a diagnosis of pneumonia. the two hcw for whom information was not available were involved in two different clusters, which did not include any other hcw with a diagnosis of pneumonia. in hospital c, 5 of the 59 hcw identified as being involved in 21 clusters, reported a respiratory tract illnesses other than pneumonia. a further eight hcw from three separate clusters, reported absence due to an influenza-like illnesses. the 66 hcw in hospital c who had been absent on sick leave for > 7 days but were not part of a cluster, included 2 who reported having had pneumonia, 14 who had had an influenza-like illness and 5 who reported an other respiratory tract illnesses. in this study, we did not observe any clusters of pneumonia in hcw employed in the same unit in any of three italian hospitals over a 1-year period. this suggests that the occurrence of a cluster of cases of pneumonia among hcw, defined as at least two cases of pneumonia among hcw in the same unit and with onset of illness in the same 10-day period, is an uncommon event. thus, our study suggests that the use of this definition to trigger an alert of the possible spread of sars [1] , or of any other respiratory infection in which occupational transmission is an important feature, would not result in an unacceptably high frequency of false positive alerts. our study was designed to determine the minimum number of alert cases that should be used to define a cluster according to who recommendations, and should not be regarded as a proposed alternative sars alert system. however, even if it is likely that a re-emergence of sars would result in at least two hcw cases of pneumonia per ward in the same 10-day period, the sensitivity of the alert system for any future strain of sars-coronavirus cannot be tested, and remains unknown. overall, the proportion of hcw taking a leave of absence > 7 days exceeded 13% with significant differences between the three hospitals (28%, 18%, and 4%, respectively). among employees of four national health system trusts in the united kingdom, 30% of all absences, and 50% of absences due to respiratory disorders (the main known cause of absence), were of > 1 week duration [3] . no reference data are available in italy for comparison with the proportions observed in our study. however, while variation in levels of absenteeism could affect the reproducibility of our study in different settings, it is unlikely that it could affect the rate of clustering of cases of pneumonia. the extent to which our results may be generalisable to other different epidemiological settings where incidence of community acquired pneumonia may be higher [4] [5] [6] remains to be determined. we may have missed clusters that included hcw with milder pneumonic illnesses, as a milder illness might have resulted in a absence of less than 7 days disability. however, current guidelines recommend at least 7 days of antibiotic treatment for pneumonia [7, 8] , and the duration of sars pneumonia was usually longer than a week [9] . finally, the occurrence of pneumonia was investigated retrospectively by interviewing hcw involved in a cluster, and thus, recall or reporting biases may have affected our results. syndromic surveillance of respiratory illnesses has also been advocated as an alerting mechanism for other naturally emerging infections, such as pandemic influenza as well as diseases due to the deliberate release of biological agents [10] [11] [12] . not unexpectedly, data from hospital c suggest that expanding the surveillance to cases of febrile acute respiratory illnesses could be more sensitive, though obviously less specific, and a more labour intensive investigation on a larger number of absences and clusters should be performed. without in-time disclosure of all diagnoses of pneumonia in hcw, the value of any alert system would be compromised. indeed, in the case of sars, the delay in implementing isolation measures while waiting for a second, clustered case of pneumonia could be considerable, and sufficient to result in a serious outbreak. if the sars alert system recommended by the who is to be implemented in countries such as ours, where clinical data on sickness absences are not collected, efforts should be made to overcome the barriers that undermine notification, balancing the need for protecting the privacy of individuals with the need for an effective surveillance. world health organization: who guidelines for the global surveillance of severe acute respiratory syndrome (sars) sars alert applicability in postoutbreak period analysis of sickness absence among employees of four nhs trusts economic burden of pneumonia in an employed population incidence of community-acquired pneumonia in the population of four municipalities in eastern finland epidemiology of community-acquired pneumonia in adults: a population-based study british toracic society: bts guidelines for the management of community acquired pneumonia in adults guidelines for the management of adults with community-acquired pneumonia. diagnosis, assessment of severity, antimicrobial therapy, and prevention severe acute respiratory syndrome syndromic surveillance and bioterrorism-related epidemics if syndromic surveillance is the answer, what is the question? systematic review: surveillance systems for early detection of bioterrorism-related diseases this work was partly supported by the ec grant episars (511063), and by the "ministero della salute, ricerca corrente, istituti di ricovero e cura a carattere scientifico."the authors thank julia heptonstall for her suggestions and editing of the text. key: cord-329350-qrxl5o1e authors: pan, angelo; matteo, giorgi-pierfranceschi; giancarlo, bosio; lorenzo, cammelli; laura, romanini title: suggestions from cremona, italy two months into the pandemic at the frontline of covid-19 in europe date: 2020-06-09 journal: clin microbiol infect doi: 10.1016/j.cmi.2020.05.038 sha: doc_id: 329350 cord_uid: qrxl5o1e nan the covid-19 pandemic is hitting hard even the most advanced health care (1). we have had to care for high numbers of severely ill patients with limited resources, i.e. ventilators and specialists in respiratory failure management, often with a lack of health-care workers (hcw): a terrible situation. the hospital of cremona, italy, is a 500-bed facility and was the second hospital hit with this tsunami-like disease in europe, on february 21st. rapidly the number of patients with covid-19 induced pneumonia reached 540. during the first eight weeks of pandemic the emergency room evaluated 1706 patients, with 1542 admissions; 242 patients were intubated, 419 underwent noninvasive ventilation (niv), and 342 died. home care was activated in 58 cases. at two months into the pandemic and in the phase of descent, we are offering advice -useful tips derived from real life experience -to our colleagues facing this disease. indications regarding preparedness are available, but a view from the "battlefield" may help in everyday practice (see factual summary) (2,3). the indications here described should be managed by a group of clinicians and management experts, in charge of the organization of the hospital in this war-like setting, this being point zero. 1. education first: it is difficult to organize continuing hcw education in an emergency setting, but it is necessary to implement courses on infection control and prevention (icp) and on covid-19 management. three main points need to addressed (4-7): a. correct use of personal protective equipment (ppe): many hcw will be displaced from their routine work to a new task, the treatment of a transmissible infection. hcw need to be rapidly updated on necessary competencies required to manage highly infectious patients with respiratory failure. rapid and thorough courses on the correct use of ppe is the first thing that should be done to protect both hcw and patients. doffing procedures are critical, due to a high risk of contamination (4, 8) . while hcw are often placing stress on the use of face masks, meticulous hand hygiene (hh) is probably the most important prevention strategy, and adherence to this is instrumental (8, 9) . b. proper nasopharyngeal swab taking is fundamental to obtain the best sensitivity/specificity of this test. c. covid-19 management: "fast and dirty" courses on should be organized on general principles of respiratory insufficiency, blood gas analysis, oxygen therapy, venous thromboembolism prevention, antivirals and anti-inflammatory drugs use (7) . intensive care patients management retraining for hcw should be performed. since indications evolve rapidly, courses should be repeated regularly. 2. implement home care: collaborating with gps to correctly manage patients at home, limiting access to the hospital only to patients with possible pneumonia, is of paramount importance. webinars on covid-19 icp strategies and management should be implemented: one hour courses on one-two items are very appreciated. 3. re-organize the emergency room (er): we saw up to 70 covid-19 patients per day: a reorganization of the er will be necessary. consider: how and where to perform triage, and to receive patients into the er -clean and covid-19 triage areas may be necessary. you may rapidly be struggling for beds and even for oxygen therapy points, since most covid-19 patients have respiratory failure. 5. extend intensive care unit and ventilation capacity: we had to increase our intubation capacity from 10 to 52 beds in three weeks. early intubation is recommended to manage covid-19 patients (7) and very rapidly you may run out ventilators. since ventilation weaning takes often over two weeks, a rapid saturation of icu is easily foreseeable, and early intubation may become a difficult problem to solve. you should program in advance when to convert areas with ventilators (i.e. operating theaters) to covid-19 intensive and semi-intensive care units. consider to prone patients to improve respiratory function. a re-organization of the staff is also fundamental since high level skills are needed to manage these patients. 6. re-organize diagnostic services: organize high throughput nasopharyngeal sars-cov-2 swabs and define which exams have to be performed to manage these patients, including d-dimer, ferritin, and il-6 determination. the need for high resolution computed tomography (hrtc), the best diagnostic exam for interstitial pneumonia will rapidly grow. (10, 11) we performed over 2400 pulmonary hrtc in march, as compared to a standard of 200. a dedicated ct service has to be organized. antithrombotic prophylaxis should not be overlooked due to increased risk of venous thromboembolism. to improve knowledge all efforts should go to treat all patients within randomized controlled trials. patients are so numerous that almost any utilized drug will rapidly go out of stock. 8. program work with shortage of hcw: it is likely that a certain number of hcw, will already be infected at the beginning of the epidemic, thus others will become infected. an emergency plan on how to reorganize services and how to re-allocate hcw to continue to offer high level services, is of primary importance. infected hcw should be visited through dedicated internal services and treated following standard procedures. 9 . check facility needs: ensure that all you need for patients with respiratory failure is in place. oxygen consumption will rapidly increase and it may become insufficient: in our hospital oxygen use skyrocketed from 3 to over 80 m3/day. drug use will increase similarly: norepinephrine and midazolam passed from 2,500 and 800 vials/month to 21,000 and 7,000, respectively. blood gas analysis syringe use will increase: in our hospital consumption passed from 1,900 in january 2020 to 12,900 in march. ppe use will be critical: mask use, i.e. surgical masks and ffp2/ffp3 respirators, increased from 5,000 to 41,000/week, impermeable gowns from 1,300 to 11,700/week, goggles/face shields from 30 to 1200/week. adequate supplies have to be organized. 10 . take into account the needs and stress of patients and hcw: patients are scared of the disease and visits, at least in our country, are forbidden. time individually spent with patients is not enough, and the whole team -doctors, nurses, nurses aids -should try to stay as close to them as possible. in our experience this is exactly what every hcw is willing to do, limiting the sense of anxiety and fear that is common during covid-19. on the hcws' side, working with covid-19 patients is an incredible stressful duty since it is a highly transmittable disease. furthermore, the level of uncertainty in management is high, the mortality is dreadful, and patients' social life within the hospital is extremely difficult. additionally, bringing home the stresses from work and worrying about the risk of transmitting sars-cov-2 infection to family members is a source of anxiety to the extent that normal marital relationship may be altered. psychological support from the very beginning of the outbreak would be very useful both for patients and hcw. the latin motto estote parati -be prepared -is what we learnt from this terrible pandemic: while waiting for possible new waves, we are working on education on ppe, hh, and ventilation, and programming how to dedicate general ward and icu to manage new covid-19 patients. finally, once the tsunami is passed you will need to have re-habilitation services to manage patients discharged after long icu stays: be prepared (12) . to conclude, we have rapidly proposed what we think could be of help to our colleagues facing covid-19 pandemic (see table 1 ). this experience has so far taught us that even in these extremely difficult situations you have to struggle for collaboration and discussion. we think that aid to coordinate such a strenuous situation could be sourced form experts in medicine of catastrophe or war medicine: the needs of the hospital, its patients and hcw undergo a rapid and dramatical change over only a few days, similar to what is observed during war. an interactive web-based dashboard to track covid-19 in real time european centre for disease prevention and control. checklist for hospitals preparing for the reception and care of coronavirus 2019 (covid-19) patients. ecdc: stockholm world health organization. critical preparedness, readiness and response actions for covid-19. interim guidance european centre for disease prevention and control. infection prevention and control for covid-19 in healthcare settings -third update how to obtain a nasopharyngeal swab specimen interim clinical guidance for management of patients with confirmed coronavirus disease (covid-19) infectious diseases society of america guidelines on the treatment and management of patients with covid-19 personal protective equipment for preventing highly infectious diseases due to exposure to contaminated body fluids in healthcare staff. cochrane database syst rev air, surface environmental, and personal protective equipment contamination by severe acute respiratory syndrome coronavirus 2 (sars-cov-2) from a symptomatic patient coronavirus disease (covid-19): spectrum of ct findings and temporal progression of the disease high-resolution chest ct features and clinical characteristics of patients infected with covid-19 in jiangsu postacute care preparedness for covid-19. thinking ahead transparency declaration • conflict of interest disclosure: that should be identical to the content of the coi form that is submitted • funding: no external funding was received acknowledgments: we want to thank pantelis tsoulfas for his thoughtful review and allegra della ragione for the language review access to data: not applicable. • contribution: 1. all authors gave substantial contributions to the conception of the work, literature search and analysis and discussion and interpretation of data all authors revised it critically for important intellectual content all authors gave final approval of the version to be published all authors agreed to be accountable for all aspects of the work. all authors ensure that all questions related to the accuracy or integrity of any part of the work have been appropriately investigated and resolved all authors have nothing to disclose.the study did not receive any external. key: cord-291810-eq7pjltx authors: reusken, chantal b; buiting, anton; bleeker-rovers, chantal; diederen, bram; hooiveld, mariëtte; friesema, ingrid; koopmans, marion; kortbeek, titia; lutgens, suzanne pm; meijer, adam; murk, jean-luc; overdevest, ilse; trienekens, thera; timen, aura; van den bijllaardt, wouter; van dissel, jaap; van gageldonk-lafeber, arianne; van der vegt, dewi; wever, peter c; van der hoek, wim; kluytmans, jan title: rapid assessment of regional sars-cov-2 community transmission through a convenience sample of healthcare workers, the netherlands, march 2020 date: 2020-03-26 journal: euro surveill doi: 10.2807/1560-7917.es.2020.25.12.2000334 sha: doc_id: 291810 cord_uid: eq7pjltx to rapidly assess possible community transmission in noord-brabant, the netherlands, healthcare workers (hcw) with mild respiratory complaints and without epidemiological link (contact with confirmed case or visited areas with active circulation) were tested for severe acute respiratory syndrome coronavirus 2 (sars-cov-2). within 2 days, 1,097 hcw in nine hospitals were tested; 45 (4.1%) were positive. of six hospitals with positive hcw, two accounted for 38 positive hcw. the results informed local and national risk management. to rapidly assess possible community transmission in noord-brabant, the netherlands, healthcare workers (hcw) with mild respiratory complaints and without epidemiological link (contact with confirmed case or visited areas with active circulation) were tested for severe acute respiratory syndrome coronavirus 2 (sars-cov-2). within 2 days, 1,097 hcw in nine hospitals were tested; 45 (4.1%) were positive. of six hospitals with positive hcw, two accounted for 38 positive hcw. the results informed local and national risk management. on 27 february 2020, the first case of coronavirus disease (covid-19) was diagnosed in the netherlands [1] . by 6 march, the number of cases had increased to 128 [2] . most of these cases had a travel history to northern italy or had been in close (household) contact with a laboratory-confirmed case. for 15 of the 128 cases the source of infection had not been determined. for seven of the 35 cases in the province of noord-brabant, the source of infection could not be established. some cases elsewhere in the netherlands were also linked to noord-brabant. furthermore, in hospital b in breda, which has offered low-threshold testing for employees with respiratory complaints since 2 march 2020, several healthcare workers (hcw) had tested positive for severe acute respiratory syndrome coronavirus 2 (sars-cov-2). on friday 6 march, the dutch national outbreak management team (omt) convened to discuss the situation of coronavirus disease in the netherlands. the omt decided that an urgent assessment of possible community transmission in the province of noord-brabant was needed. the omt decided to approach the assessment of possible community transmission in noord-brabant through sampling of hcw in hospitals in the province. a focus on hcw would simplify sampling, at such short notice, of adequate numbers of people with mild respiratory symptoms (coughing and/or sore throat and/or common cold) and without a known epidemiological link for sars-cov-2 exposure (travel to high-risk areas, close contact with confirmed case). furthermore, knowledge of the status of sars-cov-2 infection among hcw would provide important insights for the participating hospitals regarding the infection status of staff and would inform hospital policies on testing algorithms for their personnel and on infection prevention measures. seven hospitals in the province of noord-brabant were approached in the afternoon of friday 6 march and the morning of saturday 7 march 2020 with the request to test hcw through sunday 8 march. two hospitals indicated that they had already started systematic sampling of hcw as part of their hospital policy. four hospitals had no systematic sampling policy for hcw but were testing all patients that presented at the emergency ward with respiratory complaints. in addition, two hospitals just outside noord-brabant with a large proportion of staff residing in the affected province participated in the assessment (figure) . the participating hospitals were asked to offer screening to hcw and share the results of the testing by 14:00 on monday 9 march 2020. upper respiratory tract specimens (throat and/or nasopharyngeal swab) were collected from hcw with mild respiratory complaints and without epidemiological link. testing followed a uniform national protocol based on corman et al. [3] , that was rolled out by two central laboratories in the netherlands. the testing was done either locally or in one of these two central laboratories. ethical approval was not required for this study as only anonymous aggregated data were used, and no medical interventions were made on human subjects. sampling of hcw or patients was part of hospital policy. in the period 6-8 march 2020, a total of 1,097 hcw (range per hospital: 11-294) in nine hospitals were tested for sars-cov-2, of whom 45 (4.1%) were found positive ( figure) . six hospitals had positive hcw of which two (hospital b and c) accounted for 38 of the 45 positive hcw. the percentage of positive hcw per hospital varied between 0% and 9.5% with the highest percentages in hospital b in breda (4.2%; 10/238), hospital e in uden (5.6%; 2/36) and hospital c in tilburg (9.5%; 28/294). in addition, seven of the nine hospitals (a in roosendaal, b in breda, c in tilburg, d in 's-hertogenbosch, e in uden, f in eindhoven and i in nijmegen) had already tested hcw in the period from 27 february to 6 march 2020. they reported 10 positive hcw among 400 tested (2.5%). the percentage of positive hcw per hospital varied between 0% and 5.6% in this since its first emergence in china in december 2019, sars-cov-2 has caused a pandemic affecting 134 countries with a total of 142,539 covid-19 cases including 5,393 deaths by 14 march 2020 [4] . fatal outcome was reported in the largest study from china to be 2,3% [5] . as at 15 march 2020, the netherlands had officially registered 1,135 patients, with the majority of cases in the south-western part of the country [6] . currently (15 march 2020), evidence is accumulating for unnoticed community transmission in the provinces noord-brabant and limburg, with sporadic cases with unknown sources of infection elsewhere in the country. a 2-day rapid study among nine hospitals with hcw working and/or residing in an area of the netherlands with suspected community transmission showed that 4.1% of hospital staff with mild respiratory symptoms were infected with sars-cov-2. the observed geographic differences in positivity rates among hcw demonstrated focality of sars-cov-2 infection with foci in the region breda-tilburg and uden. sars-cov-2 infections among patients with respiratory complaints were primarily found in the hospital in uden. source and contact tracing was started by the regional public health service upon positive testing in the patients. the results of the rapid assessment confirmed the suspicions at the omt meeting on 6 march 2020 that unnoticed community transmission was ongoing in parts of noord-brabant. the results directly informed decisions on control measures at the national level (9 march) and subsequently for additional regional measures (10 march). the study supported the implemented mitigation policy that was advised by the omt on 6 march in anticipation of the results of the assessment [7] . the additional measures undertaken by regional authorities involved requesting inhabitants of noord-brabant to practice self-isolation at home when they developed a cough, symptoms of common cold and/or a fever. furthermore, a ban of public events involving more than 1,000 people was implemented in this province [8] . as the epidemiological situation developed, on 12 march 2020, self-isolation upon mild respiratory symptoms was implemented for the whole country, together with a ban of events with more than 100 people [9] . tailored advice was issued for people 70 years and older, persons belonging to medical risk groups and for persons involved with their care. here, we used sars-cov-2 infection rates among hcw with mild respiratory complaints without an epidemiological link as a proxy for community transmission. as the study had to be conducted under enormous time constraints (started and completed within 2 days) to be able to rapidly inform urgent decision making, there was no opportunity to roll out a standardised study protocol. nevertheless, data provided by the world health organization-china joint mission on covid-19, support our approach. the mission report indicated that there were 2,055 laboratory-confirmed cases of covid-19 among hcw from 476 hospitals in china. close investigation into these cases revealed that most of them could be traced back to exposure in households rather than in a healthcare setting [10] . we interpret the prevalence of 4% among hcw with mild respiratory illness and no epidemiological link as high and of concern. it suggests unnoticed community transmission, with a potential risk of nosocomial transmission. further evidence for ongoing community transmission was provided by the nivel primary care database sentinel surveillance for influenza-like illness (ili) and other acute respiratory infections (ari) [11] . while this is a small group of ca 40 practices covering 0.8% of the dutch population, eight ili or ari patients had tested positive by 14 march, one among 109 (0.9%) with a collection date in week 10 and nine among 125 (7.23%) in week 11. the epidemiological situation in the netherlands and elsewhere is developing rapidly, and additional measures involving further restrictions in the social life in the country are being prepared. situation report -39. coronavirus disease 2019 (covid-19) situation report -47. coronavirus disease 2019 (covid-19) detection of 2019 novel coronavirus (2019-ncov) by real-time rt-pcr situation report -54.coronavirus disease 2019 (covid-19) characteristics of and important lessons from the coronavirus disease 2019 (covid-19) outbreak in china: summary of a report of 72 314 cases from the chinese center for disease control and prevention actuele informatie over het nieuwe coronavirus (covid-19) covid-19: nieuwe aanwijzing voor inwoners noord-brabant. [covid-19: advice for residents of noord-brabant resultaat steekproef: 4% ziekenhuismedewerkers heeft coronavirus uitbreiding maatregelen coronavirus report of the who-china joint mission on coronavirus disease 2019 (covid-19). who; 2020 figures from general practitioners -additional data from sentinel stations we are grateful to the employees of the participating hospitals amphia in breda, bernhoven in uden, bravis in roosendaal and bergen op zoom, catharina in eindhoven, elisabeth tweesteden in tilburg and waalwijk, elkerliek in helmond, jeroen bosch in 's-hertogenbosch, radboudumc in nijmegen, viecuri in venray including the supporting laboratories at stichting pamm, veldhoven; microvida, roosendaal; radboudumc, nijmegen; elisabeth tweesteden, tilburg; jeroen bosch hospital, 's-hertogenbosch; erasmus mc, rotterdam; rivm, bilthoven) that managed to participate in this study under the current difficult circumstances. we thank ben bom (rivm) for the figure. none declared. ab, cbr, bd, spml, jlm, io, wvdb, pcw, dvdv, tt, jk: local study design and set-up, sampling, laboratory analysis, data compilation, co-writing manuscript. cr, cbr, mk, am, at, jvd, wvdh, jk: member of the national outbreak management team, study design, co-writing manuscript. cr, tk, avgl, if, wvdh: overall data compilation study and the netherlands, figure, co-writing manuscript. cr, am, mk: laboratory support, co-writing manuscript. mh, am: coordination and analysis nivel surveillance, co-writing manuscript. this is an open-access article distributed under the terms of the creative commons attribution (cc by 4.0) licence. you may share and adapt the material, but must give appropriate credit to the source, provide a link to the licence and indicate if changes were made.any supplementary material referenced in the article can be found in the online version. key: cord-256705-gexh2wtd authors: prescott, k.; baxter, e.; lynch, c.; jassal, s.; bashir, a.; gray, j. title: covid-19: how prepared are front-line healthcare workers in england? date: 2020-04-24 journal: j hosp infect doi: 10.1016/j.jhin.2020.04.031 sha: doc_id: 256705 cord_uid: gexh2wtd national efforts are underway to prepare the uk national health service (nhs) for the covid-19 pandemic; however, the efficacy of these interventions is unknown. in view of this, a cross-sectional survey of front-line healthcare workers (hcws) at two large acute nhs hospital trusts in england was undertaken to assess their confidence and perceived level of preparedness for the virus. the survey found that there has been moderate success in readying hcws to manage covid-19, but that more still needs to be done, particularly in relation to educating hcws about laboratory diagnostics. on 31 st december 2019 the world health organisation (who) was notified of unusual cases of pneumonia linked to a seafood whole sale market in huanan, in the chinese province of wuhan [1, 2] . by early january 2020 the causative agent was identified as a novel betacoronavirus with greater than 85% identity with a bat sars-cov genome [3] . the new virus has been named sars-cov-2 and the disease covid-19 [2] . coronaviruses are enveloped rna viruses which can infect both animals and humans and are capable of zoonotic spread. most present as mild coryzal illnesses but those of zoonotic spread such as severe acute respiratory syndrome (sars-cov) and middle east respiratory syndrome (mers-cov) can manifest with fatal respiratory illnesses [4] . with human-to-human transmission covid-19 has spread globally and was declared a public health emergency of international concern on 30 th january 2020 [1, 2] internationally, the who, and nationally public health england (phe), have issued guidance on the infection prevention and control of covid-19 (see websites for details). hcw need to be able to identify patients at risk of covid-19, and respond appropriately to any risk, in order to protect themselves and others from this infection. levels of hcw confidence and feelings of preparedness are unknown. as such we carried out an online cross sectional questionnaire based survey of front line hcw at two large acute nhs hospital trusts in england to ascertain how prepared they felt to manage covid-19. the timing of the survey coincided with a national direction to all acute nhs hospital trusts that they establish priority assessment pods for patients concerned about covid-19. thus hcw should have been prepared to encounter cases. we designed an online cross-sectional questionnaire-based survey using online surveys (formerly bos) to ascertain how confident and prepared front line hcw felt in managing potential covid-19 cases. the survey comprised of 9 questions and was anonymised by name and place of work. the first 2 questions ascertained the respondent's profession and for how many years they had been qualified. the subsequent 5 questions assessed on a rating scale how confident the hcw felt in various management aspects of covid-19. the eighth question asked respondents where, if at all, they had sought information about the virus, with a free text option for additional responses. the final question allowed free text for respondents to express anything else they wanted to highlight in terms of how prepared they felt. the online survey was live from thursday 6 th february at 10:40am until 4pm monday 17th february. it was sent to front line hcw at nottingham university hospitals nhs trust and birmingham women's & children's nhs foundation trust. those considered to be front line hcw were doctors, nurses and advanced clinical practitioners (acp) working in areas most likely to encounter early cases of covid-19. across the hospital trusts this included those working in the emergency departments, intensive care units, designated covid-19 paediatric admission areas and infectious diseases. the survey was sent to a key person in each of these areas to disseminate, with reminders sent out once the survey was live to encourage participation. at the time the survey went live work in both hospital trusts had already begun to prepare front line hcw for covid-19. as the survey was anonymised by name and place of work no ethical approval was required. between 6 th and 17 th february 158 respondents completed the survey. as it was disseminated via a key person in each area it was not possible to calculate the response rate as these figures are unknown. the results of questions 1-8 are displayed in figure 1 . question 8 allowed respondents to select more than one answer and had a free text option to enable them to elaborate on where they had sought information on the virus. responses included colleagues in infectious diseases, local infection control teams (ipc) and internet/media sources. question 9 was a free text question asking respondents if there was anything else they wanted to mention about how prepared they felt for covid-19. in total there were 30 responses. the major themes covered were to do with clarity surrounding ppe, the desire for more information/communications, concerns regarding lack of capacity to manage cases and lack of preparation in certain areas, lack of guidance around staff travel and safety to work and a request for simulations to help staff preparedness. during the last decade there have been a number of emerging infectious diseases posing a global threat to human health. hcw surveyed during these times demonstrated a lack of knowledge surrounding these pathogens and a need for further education/training [8, 9] . outbreaks of novel pathogens can be extremely stressful and detrimental to hcw; but this stress can be lessened by clear guidelines from hospitals and ipc teams [10] . healthcare systems must ensure all hcw feel equipped to manage new and emerging threats. as the threat of covid-19 grows, we wanted to assess how confident our front line hcw felt to manage possible cases. to the best of our knowledge this is the first such survey to gauge hcw feelings of preparedness in england. almost two thirds of respondents had been qualified for over 10 years, suggesting many will have been practising during the emergence of mers-cov in 2012 and ebola virus in 2013 and possibly sars-cov in 2002/3 and influenza a h1n1 in 2009. as such this cohort is likely to have some experience in preparing for novel infectious diseases. during the containment phase of a possible pandemic, healthcare systems are required to ready themselves to manage possible cases. this preparation generally starts by focussing on key front line areas and then expanding efforts throughout organisations. an important component of these preparations is providing staff with the knowledge they require to identify and manage cases. at the time this survey went live there was already formal guidance on covid-19 issued by the who and phe. in addition, the hospital trusts surveyed were actively working with front line hcw in the participating areas to equip them with the knowledge and skills needed. neither hospital trust had yet encountered a positive case of covid-19. this survey demonstrates only moderate success with these interventions with 65% of respondents feeling somewhat confident or greater in their knowledge of covid-19. however, if there is to be success in managing this pandemic, levels of hcw knowledge must rapidly increase. in view of the rapidly evolving nature of pandemics and the frequency with which information changes it is vital that hcw know where to go for up to date guidance. 78.5% of respondents felt at least somewhat confident in knowing where to go for covid-19 guidance. healthcare organisations must ensure their staff know where to access key guidance in order to reduce their anxiety and optimise their performance. it is crucial that relevant personnel are informed of possible cases of covid-19 so that these patients are managed effectively, other patients are not put at risk and that the flow of the organisation is not unduly compromised. 81% of respondents felt at least somewhat confident of who to inform of a possible case. the hopes of containment of covid-19 rely on swift and effective identification of those possibly infected. this survey found that 69% of respondents felt somewhat confident or greater in their knowledge of the criteria for identifying those at risk. a delay in identifying possible cases may have a detrimental effect on the patient, and with a reported r 0 of 2.2 put other patients and hcw at risk [1] . strategies must be implemented to enable all hcw to recognise those who may be harbouring the virus. containment of the virus also relies heavily on ipc interventions. 76% of respondents felt at least somewhat confident in how to isolate a suspected case and 71.5% of what ppe (personal protective equipment) to use. however, 65.8% had the same level of confidence in how to don and doff the ppe. this must be addressed as any lapse in ipc will place other patients and hcw at risk and could hinder containment of the virus. as shown in previous studies this can be extremely anxiety provoking for hcw [10] . this survey identified laboratory diagnostics as the area where hcw had the least confidence. only 38% of respondents were somewhat confident or greater in their knowledge of how to collect/handle laboratory samples; almost 50% were not at all confident. this may in part be because neither hospital trust had had to perform diagnostic testing at that time. in addition, whilst there was published guidance from phe on the collection and handling of diagnostic samples, local variation in laboratory testing methods, may have added to the uncertainty felt by hcw. diagnostics is a vital part of managing a pandemic, allowing early detection and isolation of cases and freeing up of resources following identification of negatives. this survey suggests hospital trusts should focus on educating hcw on the laboratory diagnostics of covid-19 through integration of guidance from laboratories and the ipc team. 67.1% of respondents had used local training/guidance to gain knowledge on covid-19. 44.3% had referred to phe guidance and 38% who guidance. 11.4% had not sought information from any additional sources and 19% had used social media. whilst employers have a responsibility to provide employees with the knowledge they require to carry out their roles, individual hcw also have an obligation to their patients to ensure they keep up to date with current guidance. in our survey respondents highlighted areas where they would like additional information and areas where they had concerns. hospital trusts should have mechanisms in place to seek out and address employees concerns to keep anxiety to a minimum and performance at its best. there are a number of limitations in this survey that should be considered when interpreting this data. it is a snap shot in time, at an early stage of preparations. the relatively small number of hospital trusts surveyed means the results may not be generalizable across england and only a small proportion of hcw in each hospital trust were surveyed. a larger scale study would be useful to add to the findings of our study. finally, this survey was assessing levels of hcw confidence not competence and there may not be a direct correlation between the two. in conclusion this survey has demonstrated that hospital trusts and individual hcw alike have acted quickly and with moderate success to make preparations for covid-19. however, more still needs to be done if they are to feel confident and prepared to tackle this global threat. in particular, we identified a lack of confidence in the collection and handling of diagnostic samples. early transmission dynamics in wuhan, china, of novel coronavirus-infected pneumonia a novel coronavirus from patients with pneumonia in china the novel coronavirus: a bird's eye view r: a language and environment for statistical computing. r foundation for statistical computing welcome to the tidyverse cowplot: streamlined plot theme and plot annotations for 'ggplot2 knowledge and attitude towards the middle east respiratory syndrome coronavirus among healthcare personnel in the southern region of saudi arabia attitudes and behaviours of healthcare workers in the kingdom of saudi arabia to mers coronavirus and other emerging infectious diseases healthcare workers emotions, perceived stressors and coping strategies during a mers-cov outbreak the authors of this manuscript would like to acknowledge the two hospital trusts and individual hcw who participated in this study. the authors of this manuscript declare no conflicts of interest. no funding was required for this study. key: cord-316266-6m9g3bdr authors: jones, peter; roberts, sally; hotu, cheri; kamona, sinan title: what proportion of healthcare worker masks carry virus? a systematic review date: 2020-06-24 journal: emerg med australas doi: 10.1111/1742-6723.13581 sha: doc_id: 316266 cord_uid: 6m9g3bdr background: concerns have been raised by healthcare organisations in new zealand that routine mask use by healthcare workers (hcw) may increase the risk of transmission of sars‐cov‐2 through increased face touching. routine mask use by frontline hcw was not recommended when seeing ‘low risk’ patients. the aim of this review was to determine the carriage of respiratory viruses on facemasks used by hcw. methods: a systematic review was conducted with structured searches of medical and allied health databases. two authors independently screened articles for inclusion, with substantial agreement (k=0.66, 95%ci 0.54 to 0.79). studies that at least one author recommended for full text review were reviewed in full for inclusion. two authors independently extracted data from included studies including the setting, method of analysis and results. there was exact agreement on the proportion of virus detected on masks. results: 1233 titles were retrieved, 47 underwent full text review and five studies reported in four articles were included. the studies were limited by small numbers and failure to test all eligible masks in some studies. the proportion in each study ranged from 0 (95% ci 0‐10) to 25% (95%ci 8‐54). no study reported clinical respiratory illness as a result of virus on the masks. conclusions: although limited, current evidence suggests that viral carriage on the outer surface of surgical masks worn by hcw treating patients with clinical respiratory illness is low and there was not strong evidence to support the assumption that mask use may increase the risk of viral transmission. this article is protected by copyright. all rights reserved. during the current novel coronavirus disease 2019 (sars-cov-2, covid-19) pandemic, the ministry of health (moh) and district health boards (dhb) have not recommended routine use of surgical masks for healthcare workers (hcw) in emergency departments (ed) in new zealand (nz). such advice was contrary to the experience of countries that had faced similar pandemics previously who recommended use of masks for ed staff within days of the first cases presenting. 1 2 the initial drivers for this were a belief that the risk to hcw from patients without epidemiological (travel/known contact) risk factors and clinical respiratory illness (cri) and fever was very low and that overuse of masks could jeopardise the available supply later in the pandemic when the prevalence of cri in the population presenting to ed would be higher. this advice was consistent with the contemporaneous world health organisation (who) guidelines on rational use of personal protective equipment (ppe) for coronavirus disease 2019, based on droplets being the most likely mode of virus transmission. 3 however, emerging evidence from the current sars cov-2 pandemic suggests that aerosol and asymptomatic spread are both possible. [4] [5] [6] the case definition in nz subsequently changed to include any respiratory illness regardless of fever or epidemiological risk. evidence has also emerged that as many of 50% of infected people are asymptomatic. 6 7 this prompted a change in advice such that currently mask use is permitted, with warnings that incorrect use of masks may be harmful, including concerns that mask use may "actually increase your risk of covid-19". 8 the aim of this review was to determine the carriage of respiratory viruses on facemasks used by hcw in acute care settings, to inform a recommendation on mask usage in the ed in the setting of an emerging viral pandemic. the primary outcome is the proportion of masks positive for any respiratory viruses. the secondary aim was to determine whether viral carriage on masks used by hcw increased or decreased the risk of cri for staff. structured searches were conducted in medline, embase and cinahl using free text and mesh terms for 'mask'; 'touch'; 'nosocomial infection'; 'contamination' and 'virus' (supplementary file). the final search was run on 23/4/20. these were supplemented by a citation search of included articles. there was no restriction on year or language. two authors independently screened titles and abstracts for relevance and selected articles for full text review. articles were included if they were clinical studies that reported virus detection on masks worn by hcw. experimental studies and computer simulation studies were excluded, as were letters to the editor or opinion pieces. agreement between authors on study selection was substantial, 10 with 97.6% exact agreement (k=0.66, 95%ci 0.54 to 0.79). all studies that at least one author recommended for full text review were reviewed in full for inclusion. two authors independently extracted data from included studies into a table including the setting, type of study, method of analysis and results. there was exact agreement on the proportion of virus detected on masks from the included studies. accepted article 6 data from included studies was shown using descriptive statistics: n, proportion, 95% confidence interval (calculated using graphpad https://www.graphpad.com/quickcalcs/confinterval1/), san diego ca, usa. when it was unclear whether studies reported virus detection on multiple sites on the same mask, we reported the highest and lowest possible proportions. risk of bias was assessed in the studies based on mask selection, method of sampling and detection, and reporting and rated as high, low or unclear. as a secondary analysis of published aggregate data, ethical approval was not required. this review was not registered in a review registry. patients and the public were not involved in this study. the searches retrieved 1233 titles and abstracts, 1186 were either irrelevant or duplicates and 47 underwent full text review (figure 1). forty studies did not report viral presence on masks and three were simulation or theoretical modelling studies 11-13 so were excluded. five studies reported in four articles met the inclusion criteria and were included. [14] [15] [16] [17] the settings, methods, proportion positive and types of viruses are presented in table 1 . the risk of bias for each study is also shown in this table. the proportion in each study ranged from 0 (95% ci 0-10) to 25% (95% ci 8-54). for the largest study with 148 participants, the proportion was 10.1% (95% ci 6-16), shown in figure 2 . none of the included studies reported whether any staff subsequently developed cri related to detectable virus on their masks. this is the first systematic review of viral detection on masks worn by hcw to our knowledge. no studies were conducted in the ed setting in the context of an emerging viral pandemic, which means the evidence relating to ed is indirect. the available evidence suggests that between 0 and 25% of masks worn by staff seeing patients with symptomatic viral illness had a detectable virus and few had virus detected on their faces after doffing masks. where reported, the viral loads on masks were small, and infectivity was not reported. without a control group not wearing masks (which may be considered unethical) it is not possible to say whether this was better or worse than not wearing a mask. the studies ranged in quality, with the main methodological concern being lack of testing of all eligible masks in several studies. there was a tendency for more testing in higher risk settings and masks that were more likely to be contaminated, which would bias towards finding a higher proportion of viral carriage on the tested masks. whilst all five studies used molecular methods to detect viral particles, the method of sampling differed with two studies reported in one article removing the outer layer of the mask, 15 two punching full-thickness 25 mm coupons from the mask 14 17 and one swabbing the surface of the outer layer. 16 three studies reported the level of detection (lod) for the polymerase chain reaction (pcr) assay. 14 16 17 this limits the comparison between studies. with respect to whether wearing masks increases facial touching by hcw, one study found that hcw wearing masks touched their faces during 29% and heads in 8% of care episodes for patients with cri. the median number of mask contacts ranged from one per hour in the near patient zone and five per hour in the far patient zone. 18 in this study, there was no control group to see how often staff touched their faces or heads when not wearing masks. in comparison, a study of medical students in a lecture found the rate of face touching to be 23 times per hour per student (without accepted article 9 masks). 19 another study found that gloves (31%) and gowns (21%) of hcw had more detectable virus than masks after single use caring for a patient with cri (12%). 16 wearing masks for more than six hours continuously and seeing more than 25 patients per shift were associated with a higher chance of mask contamination in one study. 15 none of the included studies reported cri in the staff studied, so it is not possible to say whether detecting virus on the mask leads to a higher risk of contracting cri. systematic review evidence from a previous coronavirus pandemic suggests that general use of masks may be protective for hcw in this setting, 20 21 with a number needed to treat (nnt) of six to prevent one hcw infection (meta-analysis of case control studies). 22 in contrast, there is one case report of a hcw who contracted middle eastern respiratory syndrome-related coronavirus (mers-cov) after performing cpr for one hour in full ppe on a patient with cardiac arrest due to mers-cov pneumonia with gross haemoptysis. 23 during the resuscitation the staff member was seen to adjust their mask and goggles with a heavily soiled glove. general use of masks by staff early in the course of the current 1 and previous 2 the current who advice on use of surgical masks emphasises that these should be prioritised for hcw rather than for general public use in the community. the advice for hcw is to wear a surgical mask when entering rooms "where patients with suspected or confirmed covid-19 are admitted" but does not address the use of surgical masks by hcw in ed who are seeing other patients. 25 26 given the low proportion of virus detection on masks and lack of evidence that this is linked to cri, it may be prudent for hcw in the ed to wear masks routinely in clinical areas as part of a comprehensive bundle of measures to prevent nosocomial infection. this is especially so when this article is protected by copyright. all rights reserved. although limited, current evidence suggests that viral carriage on the outer surface of surgical masks worn by hcw treating patients with cri is between 0 and 25%. no funding was sought or received for this study. the author has no financial or other relationships of interest with any manufacturer of medical masks. accepted article accepted article this article is protected by copyright. all rights reserved. escalating infection control response to the rapidly evolving epidemiology of the coronavirus disease 2019 (covid-19) due to sars-cov-2 in hong kong risk of transmission via medical employees and importance of routine infection-prevention policy in a nosocomial outbreak of middle east respiratory syndrome (mers): a descriptive analysis from a tertiary care hospital in south korea who rational use of personal protective equipment for coronavirus disease 2019 (covid-19) aerosol and surface distribution of severe acute respiratory syndrome coronavirus 2 in hospital wards an early warning system for overcrowding in the emergency department suppression of covid-19 outbreak in the municipality of covid-19: what proportion are asymptomatic? development of simulation optimization methods for solving patient referral problems in the hospital-collaboration environment information-specific-audiences/covid-19-advice-essential-workers-including-personalprotective-equipment/personal-protective-equipment-use-health-care the measurement of observer agreement for categorical data assessment of influenza virus exposure and recovery from contaminated surgical masks and n95 respirators what transmission precautions best control influenza spread in a hospital? transmission of influenza a in a student office based on realistic person-to-person contact and surface touch behaviour assessment of environmental and surgical mask contamination at a student health center --2012-2013 influenza season contamination by respiratory viruses on outer surface of medical masks used by hospital healthcare workers respiratory viruses on personal protective equipment and bodies of healthcare workers healthcare personnel exposure in an emergency department during influenza season environmental contact and self-contact patterns of healthcare workers: implications for infection prevention and control face touching: a frequent habit that has implications for hand hygiene effectiveness of masks and respirators against respiratory infections in healthcare workers: a systematic review and meta-analysis the use of masks and respirators to prevent transmission of influenza: a systematic review of the scientific evidence physical interventions to interrupt or reduce the spread of respiratory viruses: systematic review healthcare worker infected with middle east respiratory syndrome during cardiopulmonary resuscitation in korea taiwan's traffic control bundle and the elimination of nosocomial severe acute respiratory syndrome among healthcare workers infectionprevention-and-control-during-health-care-when-novel-coronavirus-(ncov)-infection-issuspected-20200125 who advice on the use of masks in the context of covid-19. interim guidance 6 covid-19: infection prevention and control guidance accepted article this article is protected by copyright. all rights reserved. this article is protected by copyright. all rights reserved. accepted articlethis article is protected by copyright. all rights reserved. key: cord-353988-xoxmugi8 authors: saleiro, sandra; santos, ana rosa; vidal, otília; carvalho, teresa; costa, josé torres; marques, josé agostinho title: tuberculose em profissionais de saúde de um serviço hospitalar date: 2007-12-31 journal: revista portuguesa de pneumologia doi: 10.1016/s0873-2159(15)30376-7 sha: doc_id: 353988 cord_uid: xoxmugi8 abstract introduction: tuberculosis (tb) is considered an occupational disease in health care workers (hcw) and its transmission in health care facilities is an important concern. some hospital departments are at higher risk of infection. objective: to describe tb cases detected after tb screening in hcw from a hospital department (ear, nose and throat – ent) who had had contact with active tb cases. material and methods: all hcw (73) from hospital são joão’s ent unit who had been in contact with two in-patients with active tb underwent tb screening. those who had symptoms underwent chest x-ray and mycobacteriological sputum exam. results: of 73 hcw who underwent tb screening, tb diagnosis was established in 9 (8 female; median age: 30 years; 1 doctor, 6 nurses, 2 nursing auxiliaries). pulmonary tb was found in 8 and extra-pulmonary tb in 1. microbiology diagnosis was obtained in 7 cases by sputum smear, n=2; culture exam in bronchial lavage, n=4 and histological exam of pleural tissue, n=1. in 4 cases, mycobacterium tuberculosis genomic dna was extracted from cultures and molecular typing was done. all cases had identical miru types, which allowed identification of the epidemiological link. conclusion: nosocomial tb is prominent and efforts should be made to implement successful infection control measures in health care facilities and an effective tb screening program in hcw. molecular typing of mycobacterium tuberculosis facilitates cluster identification. rev port pneumol 2007; xiii (6): 789-799 introdução: a tuberculose é considerada uma doença ocupacional nos profissionais de saúde e a sua transmissão, nas instituições de saúde, constitui um problema importante. alguns serviços hospitalares estão particularmente expostos a risco de infecção. objectivo: caracterizar os casos de tuberculose detectados na sequência de um rastreio efectuado aos profissionais de saúde de um serviço hospitalar (otorrinolaringologia) que contactaram com casos de tuberculose activa. material e métodos: procedeu-se à realização de rastreio de tuberculose a todos os funcionários (73) do serviço de otorrinolaringologia do hospital de são joão que contactaram com dois doentes internados com tuberculose activa. introduction: tuberculosis (tb) is considered an occupational disease in health care workers (hcw) and its transmission in health care facilities is an important concern. some hospital departments are at higher risk of infection. objective: to describe tb cases detected after tb screening in hcw from a hospital department (ear, nose and throat -ent) who had had contact with active tb cases. material and methods: all hcw (73) from hospital são joão's ent unit who had been in contact with two in-patients with active tb underwent tb screening. those who had symptoms underwent chest x-ray and mycobacteriological sputum exam. a todos aqueles que referiram sintomas foi realizada radiografia torácica e exame micobacteriológico de expectoração. resultados: dos 73 profissionais de saúde submetidos ao rastreio, foi estabelecido o diagnóstico de tuberculose em 9 (8 do sexo feminino; idade mediana: 30 anos; uma médica, seis enfermeiros e dois auxiliares de acção médica). em 8 profissionais de saúde foi diagnosticada tuberculose pulmonar, tratando-se o outro caso de tuberculose extra-pulmonar. o diagnóstico microbiológico foi obtido em 7 casos pelos seguintes métodos: exame micobacteriológico directo de expectoração, n=2; exame cultural de lavado brônquico, n=4; exame histológico de tecido pleural, n=1. em 4 casos, o dna do mycobacterium tuberculosis foi extraído das culturas, tendo sido efectuada tipagem molecular. todos estes casos apresentaram tipagem idêntica, o que permite a identificação de uma ligação epidemiológica. conclusão: a tuberculose nosocomial é relevante, sendo necessário efectuar um esforço para implementar, com sucesso, medidas de controlo de infecção nas instituições de saúde, assim como um programa eficaz de rastreio de tuberculose entre os profissionais de saúde. a tipagem molecular do mycobacterium tuberculosis facilita a identificação de clusters de infecção. palavras-chave: tuberculose, profissionais de saúde, nosocomial. results: of 73 hcw who underwent tb screening, tb diagnosis was established in 9 (8 female; median age: 30 years; 1 doctor, 6 nurses, 2 nursing auxiliaries). pulmonary tb was found in 8 and extra--pulmonary tb in 1. microbiology diagnosis was obtained in 7 cases by sputum smear, n=2; culture exam in bronchial lavage, n=4 and histological exam of pleural tissue, n=1. in 4 cases, mycobacterium tuberculosis genomic dna was extracted from cultures and molecular typing was done. all cases had identical miru types, which allowed identification of the epidemiological link. conclusion: nosocomial tb is prominent and efforts should be made to implement successful infection control measures in health care facilities and an effective tb screening program in hcw. molecular typing of mycobacterium tuberculosis facilitates cluster identification. while the last thirty years have seen a decline in the rate of tuberculosis in portugal, there is still a high incidence (33.7 new cases/100000 inhabitants in 2004) 1 esta prova foi executada através da injecção in-concern. it is also a matter for concern for hcw exposed to the risk of contagion through their jobs, such as via exposure to aerosols or poorly ventilated spaces. nosocomially transmitted tuberculosis is a very real problem 2,3,4,5 and one which demands a consideration of the infection control mechanisms adopted as part of hcw daily working practices 6 seventy three ent hcw were screened for tb. of these, 24 (32.8%) were referred for a pulmonology appointment for suspected tb, as they were positive in the tuberculin test (all) with one patient in addition having a dry cough. the hcw with suspected tb were evaluated via chest x-ray, mycobacteriological sputum smear, bronchofibroscopy with bronchial lavage, diagnostic thoracocentesis and pleural biopsy. all 24 hcw underwent chest x-ray, which showed abnormalities in 10 cases. six had expectoration and underwent mycobacteriological smear sputum exam and culture, which was positive in 2. seven underwent bronchofibroscopy with bronchial lavage. in 2 cases, this was performed as the mycobacteriological sputum smear was negative and in the other 5 as they did not (fig.1 ). sete dos 9 doentes apresentavam sintomas sugestivos de tuberculose present expectoration. diagnosis was made in 4 cases. one patient, with chest x-ray showing left pleural effusion, underwent diagnostic thoracocentesis and pleural biopsy. the latter method was conclusive in diagnosing tb. the evaluation and study allowed the diagnosis of 9 cases of tb (12.3%) and 3 cases of latent tuberculosis (4.1%). eight of the 9 new tb cases were female and 1 male. mean age of the patients was 30 years old (23-61 years). six were nurses, 2 nursing auxiliaries and i a doctor (fig.1) . seven of the 9 patients presented symptoms suggesting tb (fig. 2 ). x-rays showed pulmonary infiltrates (fig. 2) . a apresentação radiológica dos casos distribuiu-se da seguinte forma: infiltrado pulmonar em 6 doentes; nódulo pulmonar em 2 casos e derrame pleural em 1 doente (fig. 3) . o diagnóstico de tuberculose foi confirmado microbiologicamente através da identificação de mycobacterium tuberculosis em 6 casos; num caso houve confirmação histológica, pela presença de granulomas epitelióides com necrose caseosa em retalhos de pleura parietal; em 2 casos foi assumido o diagnóstico de presunção (fig. 4) . um dos 9 casos de tuberculose apresentava derrame pleural esquerdo, que foi estudado, tendo para esse efeito sido realizada toracocentese diagnóstica (ada: 119 u/l; exame directo e cul-in 6 patients, pulmonary nodules in 2 and pleural effusion in 1 (fig. 3) . tb diagnosis was confirmed microbiologically via identification of mycobacterium tuberculosis in 6 cases. histological diagnosis was used to confirm one case, identifying epithelioid granulomas with caseous necrosis in sections of parietal pleura. two cases had a presumed diagnosis only (fig. 4) . one of the 9 tb cases presented left pleural effusion. diagnostic thoracocentesis ada: 119 u/l was performed to study this. smear and culture exam of the pleural liquid was negative. mycobacterium tuberculosis study of the pleural liquid using the polymerase chain reaction molecular biology technique was negative. pleural biopsy was performed as histological exam of the pleura fragments (table i) . a presumed diagnosis was made in 2 cases as the mycobacteriological exams (smear, culture and polymerase chain reaction) of the bronchial lavage were negative. one patient had respiratory (chest pain) and bodily (fever) symptoms, a posassim, verificou-se que em 2 casos os exames micobacteriológicos (directo, cultural e polymerase chain reaction) do lavado brônquico foram negativos, tendo sido assumido um diagnóstico de presunção. um dos doentes apresentava sintomas respiratórios (toracalgia) e constitucionais (febre), prova de tuberculina positiva e alteração radiológica (nódulo pulmonar no lobo superior direito), pelo que efectuou tratamento com anti--bacilares de primeira linha durante seis meses, tendo ficado assintomático. por outro lado, a tomografia computadorizada torácica de controlo, realizada 8 meses depois do início do trata-itive reactive to the tuberculin test and x--ray abnormalities (pulmonary nodule of the right upper lobe) and so was prescribed first line anti-bacillary treatment for six months, after which symptoms disappeared. in addition, a control chest ct scan made 8 months after start of treatment showed the nodular lesion on the right upper lobe had decreased in size. while the other patient had no symptoms, there was a positive reactive to the tuberculin test and x-ray abnormalities (pulmonary infiltrates in both upper lobes). anti--bacillary treatment was prescribed for six months, after which a control chest ct scan showed resolution of the abovementioned pulmonary infiltrates, with patient remaining asymptomatic. mycobacterium tuberculosis genomic dna was extracted from cultures in 4 of the 9 patients. in 3 cases the culture was of bronchial lavage and in one case sputum. molecular typing was then carried out, using three cases of latent tb were also identified, one in a 54 year old nurse, one in a 50 year old nurse and one in a 32 year old nursing auxiliary. these were diagnosed due to positive reaction to the tuberculin test as patients did not present any symptoms of tb and chest x-rays did not show any abnormalities suggesting the disease. these 3 health care workers were prescribed chemo-prophylaxis with isoniazid, rifampicin and pyrazinamide for 2 months. seventy three hcw from the hsj ent department were studied. they had been in probable contact with 2 ent in-patients with active pulmonary tb who had undergone tracheotomy and were infectious. evaluation revealed tb disease in 9 and tb infection in 3, corresponding to a tb rate of 12328.8 per 100000 persons. this high rate of tb in hcw as compared to the population at large is a matter of concern, and has been documented in other studies 4, 5, 7, 8, 9, 10, 11 . our results underline the importance of and the need to abide by hospital-wide infection control measures 12 . we stress the higher rate usually seen in nurses, perhaps due to their closer and more prolonged contact with the 4, 5, 7, 8, 9, 10, 11 . os resultados apresentados neste trabalho alertam para a importância e a necessidade do cumprimento de medidas de controlo de infecção a nível hospitalar 12 . de referir que o grupo profissional de enfermagem, talvez porque tenha um contacto mais próximo e prolongado com o doente infectante durante a realização de actividades, com exposição a aerossóis, apresenta, habitualmente, valores de incidência de tuberculose mais elevados 3,7,8 . as técnicas de tipagem molecular, nomeadamente a de mycobacterial interspersed repetitive unit (miru) ou a de restriction fragment length polymorphism (rflp), facilitam a identificação de clusters de infecção 13, 14, 15, 16, 17 . o rastreio da tuberculose é essencial para a detecção da doença e seu tratamento precoce 18 . infectious patients during activities with exposure to aerosols 3, 7, 8 . molecular typing techniques, particularly mycobacterial interspersed repetitive unit (miru) or restriction fragment length polymorphism (rflp), make it easier to identify infection clusters 13, 14, 15, 16, 17 . screening for tb is vital in the early detection and treatment of this disease 18 . ponto da situação epidemiológica e indicadores de desempenho divisão de doenças transmissíveis tuberculosis in health care personnel in a general hospital risk of tuberculosis among healthcare workers: can tuberculosis be considered as an occupational disease increased risk of tuberculosis among health care workers in samara oblast, russia: analysis of notification data occupational risk of tuberculosis among health care workers at the institute for pulmonary diseases of serbia guidelines for preventing the transmission of mycobacterium tuberculosis in health-care facilities tuberculosis among health care workers in a short working period tuberculosis among health care workers at king chulalongkorn memorial hospital tuberculosis in health care workers in a central hospital in malawi risk of mycobacterium tuberculosis infection and disease among health care workers increased risk of tuberculosis in health care workers: a retrospective survey at a teaching hospital in istanbul, turkey guidelines for preventing the transmission of mycobacterium tuberculosis in health-care settings mycobacterial interspersed repetitive unit typing of mycobacterium tuberculosis compared to is6110-based restriction fragment length polymorphism analysis for investigation of apparently clustered cases of tuberculosis van soolingen d. molecular typing of mycobacterium tuberculosis by mycobacterial interspersed repetitive unit-variable-number tandem repeat analysis, a more accurate method for identifying epidemiological links between patients with tuberculosis sensitivities and specificities of spoligotyping and mycobacterial interspersed repetitive unit-variable-number tandem repeat typing methods for studying molecular epidemiology of tuberculosis molecular epidemiology of tuberculosis outbreak of multiple drug--resistant tuberculosis in lisbon: detection by restriction fragment length polymorphism analysis nosocomial transmission of mycobacterium tuberculosis found through screening for severe acute respiratory syndrome -taipei key: cord-306247-259zacce authors: garnica, marcia; valentim, marcia rejane; furtado, paulo; moreira, maria claudia; bigni, ricardo; vinhas, simone; dias, paulo cesar; fellows, ilza; martins, wolney title: covid-19 in hematology: data from a hematologic and transplant unit date: 2020-09-06 journal: hematol transfus cell ther doi: 10.1016/j.htct.2020.08.004 sha: doc_id: 306247 cord_uid: 259zacce during the covid-19 pandemic, special attention has been addressed in cancer care to mitigate the impact on the patient’s prognosis. we addressed our preparation to face covid-19 pandemic in a hematological and stem cell transplant unit in brazil during the first two months of covid-19 pandemic and described covid-19 cases in patients and health care workers (hcw). modifications in daily routines included a separation of area and professionals, sars-cov-2 screening protocols, and others. a total of 47 patients and 54 hcw were tested for covid-19, by pcr-sars-cov-2. we report 11 cases of covid-19 in hematological patients (including 2 post stem cell transplant) and 28 cases in hcw. hematological cases were most severe or moderate and presented with several poor risk factors. among hcw, covid-19 were mostly mild, and all recovered without hospitalization. a cluster was observed among hcw. despite a decrease in the number of procedures, the transplant program performed 8 autologous and 4 allogeneic sct during the period, and 49 onco-hematological patients were admitted to continuing their treatments. although we observed a high frequency of covid-19 among patients and hcw, showing that sars-cov-2 is disseminated in brazil, hematological patients were safely treated during pandemic times. since all the world has been facing covid-19 pandemic, concerns about hematological patients have been addressed. 1, 2 new diagnosis of acute or chronic leukemia, lymphoma, multiple myeloma is still being made, and patients must go on in their treatments to maintain response and prognosis. there are few reports about hematologic patients and covid-19 until now, but they reported more severe disease in this population. [3] [4] [5] [6] [7] the rationale is that hematologic cancer confers immunosuppression by itself or by its treatment, and it is already known that the development of any severe infection can modify the treatment schedule, impacting prognosis. another special issue in covid-19 scenario is about the access and the quality care of cancer therapy since there are overcrowded hospitals and deficiencies in blood supplies. covid-19 was first noted in brazil at the end of february, and a few days after, community transmission was documented. in the last two months, it spread to all brazilian regions. brazil faces severe difficulty in access diagnosis tests for all, so testing has been used mostly for individuals in risk group conditions, health care professionals, or patients who require hospitalizations. 8 in this manuscript, we address our preparation to face the covid-19 pandemic during the first two months and describe covid-19 documented cases in patients and health care workers (hcw): from diagnosis to outcomes. this is a case series study from hematological patients treated from march 12 th to may 21 th in complexo hospitalar de niterói, a quaternary level hospital, reference for stem cell transplantation (sct), and solid organ transplant in rio de janeiro, brazil. the study period coincides with the first 2 months after the documentation of community transmission of covid-19 in brazil. the hospital has a sct program since 2007 and performs a median of 100 autologous and 30 allogeneic sct (related and unrelated) per year. the transplant unit (utx) has 26 hepa filtered single-room beds and receives patients for sct and also hematological patients for chemotherapy and immunotherapy. a day-clinic hospital with 15 beds also integrates the unit. this study was approved by the institutional ethics committee (number 30907420.1.0000.5455). since who declared covid-19 a public health emergency of international concern in january 31 th , the transplant unit planned modifications regarding daily routines, in addition to intense modifications in all hospital. after who declared covid-19 a pandemic, a covid-19 committee was formed to coordinate all actions and specific areas for covid-19 patients where delimited, intended not to permit crossover of covid-19 and other patients. regarding the transplant unit, hematology staff, transplant infectious diseases specialist, and transplant coordination have generated guidelines to best balance the risk of baseline malignancies with the risk of covid-19 infection and mortality. international and national recommendations were references for our actions, as well as reports from other transplant centers that had previously faced covid-19. care modifications included inpatients and outpatients; transplant indication timing; blood cell supply; and intensive care unit. firstly, we focused on patient and family education about the importance of social distancing, hand hygiene, and masking. written material was distributed to all. restriction in people circulation inside the utx has been applied, and several modifications were implemented before and ongoing the pandemic weeks. we limited inpatients caregiver to one, and visitors are strictly limited. utx entrance has been confined to a single point, where all patients, families, and hcw are screened regarding symptoms and exposition. patients with any symptoms regarding covid-19 are masked and transferred to a specific emergency room to be tested. hcw or families that are symptomatic are not allowed to enter the unit. since the beginning of the program, medical staffs' surveillance of respiratory symptoms was intensified and testing all symptomatic has been routine. regarding patients care, all admissions of sct, donor and recipient, scheduled chemotherapy, or unscheduled admissions such as febrile neutropenia, and others have been clinical and laboratory screened by sars-cov-2 pcr. we gave continued training regarding secure, ipe, hospital and transplant flows, intubation, and others for all staff, and relevant data have been shared with all. for this analysis, epidemiological, clinical, and laboratory data from covid-19 cases were reviewed, and the outcome described. for hcw, we performed a web questionnaire. this questionnaire was applied twice, with 30 days apart, to identify covid-19 cases. data were reported as frequencies, proportions, or medians. the chi-squared test was applied to compare frequencies and rates. kaplan-meir was applied to survival analyses, and curves were compared by log-rank. we defined a statistically significant p-value lower than 0.05. a total of 47 onco-hematologic patients were tested for covid-19 in the unit. the screening was performed using sars-cov2 pcr for all cases. the test was applied to 30 symptomatic and 17 asymptomatic patients. screened asymptomatic patients were: sct donors (n = 4), sct recipients (n = 10), hematological patients before scheduled chemotherapy (n = 3). no positive test was noted in asymptomatic screening, but only in symptomatic patients (10 cases; 33% of symptomatic; 21% of all tested). a covid-19 case performed the test in other hospital, but she was transferred to our hospital to treatment. screening was done in 54 health care workers: 40 symptomatic and 14 asymptomatic justified by exposure to sars-cov-2. only symptomatic hcw tested positive (28 cases; 70% of symptomatic, 52% of tested). frequencies of covid-19 in tested and symptomatic hcw were higher compared to hematological patients (52% vs. 21%; p = 0.003 and 70% vs. 33%; p = 0.005; respectively). eleven onco-hematological patients were diagnosed with covid-19, including two recipients of haploidentical stem cell transplant (both late phase post sct -after d + 100), and 9 patients with onco-hematological malignancies. clinical and laboratory data are shown in table 1 . regarding haploidentical patients, they were treating chronic severe gvhd at the moment of covid-19, and immunosuppression included corticosteroids. regarding onco-hematological patients, two episodes of covid-19 were noted in untreated newly diagnosed patients. most cases were moderate or severe (n = 9; 82%), and 5 (45%) died due to covid-19. one patient is still on treatment, but recovering. the timeline of covid-19 cases is represented in fig. 1a . our first case of covid-19 in hematological patients was documented on march 30 th , in another hospital, and the number of cases increased after april 15 th . three patients developed covid during hospitalization, but in two, a close relative was the probable source of infection. in the other patient, the source could be intrahospital. in all the others, covid-19 symptoms were present at hospitalization, and the patient was treated outside utx. regarding hcw, covid-19 cases started earlier comparing to hematological patients, but most hcw cases occurred after the second week of april, with a cluster distribution of thirteen cases in 2 weeks. (fig. 1b) after this cluster, training and screening were intensified, and universal use of masks during all hospital stay, including hcw common areas, was then implemented. hcw cases still occurred but in more regular distribution during weeks. fig. 2.1 shows the cumulative incidence of covid-19 in hcw, and fig. 2 .2, the incidence by professional categories (p = 0.13). the spread in number of covid-19 in hematological patients and in hcw after second week of april is similar to cases distribution in rio de janeiro state during the same period (fig. 3) . during the same two months, a total of 61 hematological patients were admitted in the utx. autologous and allogeneic sct was performed in eight and four patients, respectively. despite two autologous patients (admission in utx occurred before the documentation of community transmission in brazil), all recipients and donors were screened by sars-cov-2 pcr before admission or stem cell harvest. no covid-19 was observed in sct during the early phase. our experience during the initial months of covid-19 pandemic highlighted some observations: covid-19 presents as moderate or severe cases in onco-hematological patients, and the mortality was high. high intensively treated patients or those with comorbidities were at worse risk for severe covid. a large proportion of hcw experienced covid-19, independently of the category of professionals. we could observe a cluster of covid-19 in hcw, suggesting possible transmission within hcw. after intensified measures, the spread of cases in patients and hcw were similar to those reported in our state, and the unit was maintained as a "covid-19 free zone". regardless of the pandemic, the transplant program was continued but had a 50% reduction in autologous transplants procedures. regarding allogeneic, we did not experience a reduction in transplants procedures. this workforce priories the importance of keep cancer treatment going, and so mitigate the impact of postponing sct in high risk cancer patients. the knowledge of covid-19 is in progression. the disease was first documented a few months ago but is now spreading worldwide. description of manifestations and outcomes from specific sub-settings of patients is a mandatory issue for a better understanding of this new pathology and provides tools to face it. [10] [11] [12] [13] few reports addressed hematological patients. data from china and france reported concerning outcomes: 85% and 40% mortality rates among hematological patients, respectively. 3, 4 most patients had other comorbidities despite hematological cancer, and the covid-19 manifestation was frequently severe, requiring mechanical ventilation and intensive care in a high proportion of cases from both series. data from italy, including solid tumor patients, showed better outcomes than china and france series, but all authors concluded that covid-19 has a worse evolution in cancer patients compared to non-cancer population. 5, 6 in our series, the mortality rate was similar to france reports. we also find poor laboratory markers and severe pulmonary involvement at the onset of severe diseases. on the other hand, mild and moderate cases at onset had uncomplicated evolution. it is important to address that their and our cases were all symptomatic patients that had a documented covid-19. it is a crucial bias since asymptomatic or oligosymptomatic cases are not documented unless they require medical assistance or hospitalization for other reasons. there is a possible overestimation of complications and mortality rates. regarding hcw, we report a high incidence of covid-19 regardless of the professional category, and we were unable to establish an association with work characteristics such as frequency and work in more than one hospital. hcw cases increased concomitantly with cases in our state, but we could observe a cluster at the beginning of transmission. this fact suggests that a possible transmission within hcw happened, as all covid-19 onco-hematological patients were managed outside the utx, and no case in the hospitalized patient was identified in the same period. the covid-19 rate in hcw was higher than some reports from italy, 5,14 but similar to first reports from china. 15 cluster distribution was also noted in singapore and china. 16, 17 hcw is considered a high-risk group for infection and transmission, but fortunately most cases were mild. 18 this high incidence of covid-19 in hcw highlighted the importance of intense screening, regular training, and adequate personal protective equipment to limit the spread and to reduce the risk for hcw to become infected. any symptoms or suspected community exposition should be managed as a possible case, and the hcw must be removed from work until appropriate documentation. the frequency of testing positive was 70% in symptomatic hcw, a very high proportion compared to symptomatic onco-hematologic patients. although, we did not find covid-19 documentation in asymptomatic hcw, pre-symptomatic transmission is of great concern. impact of asymptomatic hcw screening is not clear, but measures to reduce pre-symptomatic transmission must be implemented. 16 despite the pandemic, transplant programs from other countries maintained the program active, as postponing transplantation is not feasible in some scenarios. the european society for blood marrow transplantation (ebmt) and the brazilian society for blood marrow transplantation (sbtmo) recommendations allow procedures if the patients' safety is maintained. 19, 20 we decided to maintain the program active but limited the procedure to those in which the prognosis would be impacted by postponing transplantation. this decision was based on an intense collaboration of the institution as a whole and revised with daily results. 10, 21 asia, europe, and north america are in a different pandemic phase compared to brazil. these regions are reopening, but brazil has not achieved the peak of incidence yet and has an increasing number of infected and deaths daily. unfortunately, all the world is exposed to second or more waves of covid-19, until an efficient vaccine is available. sars-cov-2 will remain a concern for a long time. we hope our experience may contribute to a better comprehension of the disease in the onco-hematological scenario and improve the capacity to mitigate the negative impact in cancer care assistance during the pandemic. caring for patients with cancer in the covid-19 era facing covid-19 in the hematopoietic cell transplant setting: a new challenge for transplantation physicians covid-19 in persons with haematological cancers covid-19 outcomes in patients with hematologic disease cancer treatment during the coronavirus disease 2019 pandemic: do not postpone, do it! the experience on coronavirus disease 2019 and cancer from an oncology hub institution in milan, lombardy region covid-19 in persons with chronic myeloid leukaemia painel covid19 painel coronavirus provision of cancer care during the covid-19 pandemic frequently asked questions regarding sars-cov-2 in cancer patients-recommendations for clinicians caring for patients with malignant diseases covid-19 and cancer: what we know so far considerations for managing patients with hematologic malignancy during the covid-19 pandemic: the seattle strategy low rate of severe acute respiratory syndrome coronavirus 2 spread among health-care personnel using ordinary personal protection equipment in a medium-incidence setting risk factors of healthcare workers with corona virus disease 2019: a retrospective cohort study in a designated hospital of wuhan in china containment of covid-19 cases among healthcare workers: the role of surveillance, early detection, and outbreak management a cluster of health care workers with covid-19 pneumonia caused by sars-cov-2 epidemiology of and risk factors for coronavirus infection in health care workers the challenge of covid-19 and hematopoietic cell transplantation; ebmt recommendations for management of hematopoietic cell transplant recipients, their donors, and patients undergoing car t-cell therapy sbtmo how do we plan hematopoietic cell transplant and cellular therapy with the looming covid-19 threat? the author declares no conflicts of interest.q3 r e f e r e n c e s key: cord-351022-8y43jhmu authors: schwartz, carmela; oster, yonatan; slama, carole; benenson, shmuel title: a dynamic response to exposures of healthcare workers to newly diagnosed covid-19 patients or hospital personnel, in order to minimize cross transmission and need for suspension from work during the outbreak date: 2020-09-01 journal: open forum infect dis doi: 10.1093/ofid/ofaa384 sha: doc_id: 351022 cord_uid: 8y43jhmu background: during the corona virus disease (covid-19) epidemic, many healthcare workers (hcws) were exposed to infected persons, leading to suspension from work. we describe a dynamic response to exposures of hcws at the hadassah hospital, jerusalem, to minimize the need for suspension from work. methods: we performed an epidemiological investigation following each exposure to a newly diagnosed covid-19 patient or hcw; close contacts were suspended from work. during the course of the epidemic, we adjusted our isolation criteria according to the timing of exposure related to symptoms onset, use of personal protective equipment and duration of exposure. in parallel, we introduced universal masking and performed periodic sars-cov-2 screening for all hospital personnel. we analyzed the number of hcws suspended weekly from work and those who subsequently acquired infection. results: in the 51 investigations conducted during march-may 2020, we interviewed 1095 hcws and suspended 400 (37%) from work, most of them, 251 (63%), during the first two weeks of the outbreak. the median duration of exposure was 30 minutes (iqr, 15-120). only 5/400 (1.3%) developed infection, all in the first two weeks of the epidemic. after introduction of universal masking and despite loosening the isolation criteria, none of the exposed hcws developed covid-19. conclusions: relatively short exposures of hcws, even if only either the worker or the patient wore a mask, probably poses a very low risk for infection. this allows us to perform strict follow-up of exposed hcws in these exposures, combined with repeated testing, instead of suspension from work. as of may 2020, israel has experienced more than 19,000 cases of coronavirus disease (covid-19) (1777 cases/million) and more than 300 deaths (33 deaths/million) (1) . jerusalem and its surroundings is the area with the highest prevalence of covid-19 patients in israel (2) .health care workers (hcws) are at increased risk of exposure to infected persons (3) , and concern aroused early in the course of the epidemic that a substantial number of hcws might need to be suspended from work. this could seriously affect the functioning work force available at the hospital (4) (5) . understanding of the mode of transmission of severe acute respiratory syndrome corona virus 2 (sars-cov-2), and strict guidelines for personal protective equipment (ppe) during direct patient contact and any interactions between hcws in the hospital, are essential for ensuring staff protection and safety (6) . furthermore, immediate epidemiological investigation and, if needed, early suspension from work of exposed hcws is needed in order to limit the spread of infection to and between hcws and patients (7) (8) . in this research, we describe the outcomes of our dynamic response to exposures of hcws to newly diagnosed positive patients or personnel, aimed at minimizing infection of hcws and cross transmission during the covid-19 outbreak. (supplementary table) . especially at the beginning of the epidemic, in the second week of march, many health care workers (hcws) were exposed to covid-19 patients, in the hospital or outside. immediate epidemiological investigations of exposed hcws were initiated, in order to break the chain of cross-transmission between hcws as well as avoiding transmission from hcws to patients, thus keeping maximal work force available. a c c e p t e d m a n u s c r i p t 7 the ipc team got a notice of any positive covid-19 hcw or patient in the hospital, either from the ministry of health (in a few hours after positive test results) or automatically from the hospital laboratory through the computerized information system (immediately upon verification of a positive test). in order to identify every possibly exposed hcw, a thorough epidemiological investigation was initiated immediately, even during evening shifts and weekends. the ipc team interviewed every such hcw and recorded the exact circumstances and duration of the encounter. we defined close contact as exposure of at least 15 minutes, in proximity of less than two meters, to a positive covid-19 person (9) . in case of a contact of less than one meter, we considered even five minutes of exposure as a close contact. according to the centers for disease control (cdc) guidelines (10), wearing of ppe by the index case and/or the exposed hcw should be taken into consideration when deciding upon the need for home isolation of the exposed hcw. if both the index case and the hcw wore a facemask (surgical mask or n95 respirator), there was no need for isolation. the same decision was applied if the index case did not wear a facemask but the hcw wore a facemask and a face shield (table 1) . during the course of the epidemic and the evolving understanding of the infectivity and transmission of sars-cov-2, we adjusted our criteria for home isolation of exposed hcws (supplementary table) . during the first two weeks of the epidemic in israel, all exposed hcws meeting the criteria for close contact were suspended from work for 14 days. after two weeks (on march 20), during which over 250 hcws were sustained from work, the need a c c e p t e d m a n u s c r i p t 8 for home isolation was redefined according to the following principles: 1) if the index case was symptomatic at the time of exposure (e.g., fever or chills, respiratory symptoms, loss of smell or taste), all close contacts were sent to home isolation for 14 days following exposure date. 2) if the exposure occurred more than four days before the index case developed symptoms, since most patients are only infective within four days prior to symptoms (11), isolation was not required. 3) if the exposure occurred four days or less before the index case developed symptoms (if the index case never had symptoms, than within four days before the positive sars-cov-2 test), isolation was required for ten days since the last exposure and return to work was approved after a negative nasopharyngeal pcr test on day ten (12) . these principles are summarized in table 2 . we asked every exposed hcw to inform us immediately in case of any evolving symptoms. needless to say that every exposed employee who developed any suspicious symptoms was tested for the presence of sars-cov-2, and suspended from work while the results were pending. after relieve of symptoms and a negative test result, the employee was allowed back to work. in the beginning of the epidemic in israel (march 2020), we recommended the use of ppe for direct contact with suspected or positive covid-19 patients, according to the cdc and israeli ministry of health guidelines at that time (13-14). covid-19 positive patients were isolated in the designated wards and all hcws entering the area wore full airborne isolation ppe, e.g. waterproof gown, gloves, n95 respirator, face shield and head cover. patients with suspected covid-19, according to symptoms or because of exposure to a positive person, were put in isolation rooms and hcws entered the room while wearing surgical mask, face a c c e p t e d m a n u s c r i p t 9 shield, disposable gown and gloves. in these patients, in case of severe respiratory symptoms or aerosol producing procedures, ppe was upgraded to full airborne protection as described above. in the light of many exposed hcws, during the last week of march 2020, the ipc team required the use of surgical masks by hospital personnel during every patient contact. in addition, staff meetings were restricted to ten attendees and allowed only while adhering to rules of social distancing, and interaction between staff during shifts was kept to a minimum. in parallel, a routine periodic screening program for sars-cov-2 of all hcws was introduced at the hospital (15) . this included summoning all employees for pcr testing for sars-cov-2 performed on nasopharyngeal swabs. the employees were asked to undergo a second test after five days. periodic screening of all hcws is continues at the hospital until these days. on april 7, we changed our policy to universal masking of hcws and visitors at all times and of patients during any contact with a hcw. we used descriptive statistics for all investigations performed on hcws who were exposed to a covid-19 patient or colleague and their outcomes. categorical variables are presented with percentages and continuous variables are presented with median and inter-quartile range (iqr). we describe the number of hcws suspended weekly from work and those subsequently acquiring infection over the course of the epidemic. additionally, we examined the input of the changing strategies of ppe and criteria for suspension from work on these outcomes. we used extended mantel-haenszel test to compare the rates of hcws that we sent to home isolation in each investigation, before and after the demand for a c c e p t e d m a n u s c r i p t 01 masking of hcws (winpepi version 11.60). significance was two tailed and determined at p<0.05. between march 8 and may 23 (11 weeks), we performed 51 exposure investigations. in 23/51 (45%) the index case was a hcw and in 28/51 (55%) a patient (emergency department, 8 (29%); delivery room, 7 (25%); medical, 8 (29%); surgical, 3 (11%); outpatient clinics, 2 (7%)). in five out of these exposure investigations (10%), the index case was asymptomatic throughout the course of his disease. altogether, we interviewed 1095 hcws (table 3) . out of these, 400 (37%) hcws had close contact as defined by the cdc (10). most of these were relatively short exposures (median 30 min, iqr, 15-120). in most of these exposures, either the hcw and/or the index case were not fully protected as defined by the cdc guidelines (both without a mask, 360 (90%); only one with a mask, 36 (9%); both masked but exposure greater than three hours, 4 (1%)). these workers were suspended from work and sent to home isolation. the vast majority of hcws, 251/400 (63%) were sent to home isolation during the first two weeks of the outbreak. of all hcws sent to home isolation following these investigations, only 5/400 (1.3%) developed infection with covid-19 during the period of isolation, all at the very beginning of the epidemic (graph). none of the hcws investigated because of potential exposure, but not sent to isolation, had developed covid-19. since our hospital performed routine screening for sars-cov-2 on all hcws, we were able to check and ascertain that we did not miss any positive hcw whom we might not have march 22, no hcw who was exposed after this change was infected until the end of the study period (graph). healthcare workers are at increased risk of acquiring covid-19 from unrecognized patients or colleagues during work (16) (17) . at the very beginning of the epidemic in israel, the ipc team of our hospital started epidemiological investigations of every exposure to a newly diagnosed sars-cov-2 positive patient or hcw. the first investigations resulted in the need to suspend a large number of hcws from work, requiring home isolation. serious concern aroused that departments would need to be totally shut down, threatening the ability of the hospital to keep functioning over time. as soon as we learned in mid-march 2020 from the cdc guidelines at that time, that wearing ppe (facemask with or without face shield) could reduce the need for excluding exposed hcws from work (14), we updated our rules of protection. we introduced universal masking for hospital personnel, patients and visitors and social distancing between hcws. later on, this approach was suggested also in the literature (6) . since then, the number of hcws whom we needed to suspend from work decreased significantly. as shown in the graph, this decline happened while the epidemic in israel was still on the rise. a single report from minnesota department of health, usa, also showed a reduction in hcws infections in the hospital following the introduction of universal masking (18) . in addition, and according to new accumulating knowledge, we redefined the criteria for suspension from work and duration of isolation required (14) . we differentiated between exposures to symptomatic or asymptomatic index cases and reduced the duration of home isolation needed after exposure to an asymptomatic index case. since 95% of exposed people who become infected, do so within 10 days from exposure, we performed sars-cov-2 nasopharyngeal test on day 10 for isolated workers, prior to allowing them to return to work (12) . by that, we further reduced the number of hcws excluded from work at a given time. during 51 epidemiological investigations performed, out of 1095 potentially exposed hcws whom we thoroughly interviewed, we defined 400 as close contacts, prompting suspension from work. out of these, only five developed clinical signs of infection with sars-cov-2, all in the early phase of the covid-19 outbreak. although we narrowed the criteria for isolation, none of the hcws investigated, but not isolated, developed clinical signs of infection with covid-19. owing to the periodic universal screening of all hcws performed at our hospital, we were assured that there were no eventual asymptomatic hcws among those investigated or isolated. additionally, the proactive screening allowed us to assume that we probably did not miss any close contact during our investigation process, who potentially could become positive. furthermore, the results of this study raises the question whether the criteria for isolation were still too rigorous, since, after the initial phase, none of the hcws excluded from work developed covid-19. in the light of these findings, and in the presence of universal masking and social distancing, it might be worth to consider substitution of suspension from work of exposed hcws by rigorous follow-up of symptoms together with repeated testing on days a c c e p t e d m a n u s c r i p t 03 five and ten after exposure. this approach was recently studied in a mathematical model performed by . there are some limitations to this study: due to the retrospective nature of epidemiological investigations, there is a recall bias and hence, in some cases it was not trivial to define each contact unequivocally. our criteria for home isolation after exposure may need further specification. accumulating knowledge on the infectivity of asymptomatic or presymptomatic patients might shed light on this issue (20) . in addition, despite periodic screening of all hcws, since we did not test them every day, we still might have missed asymptomatic positive personnel; however, we assume that the chance for that is negligible. our experience might be valid in hospitals with dedicated covid-19 departments and universal masking, and we assume that this by now is the standard of care in most countries. in conclusion, after introducing universal masking for hcws, patients and visitors, and social distancing, none of the exposed hcws developed covid-19. based on the results of our study, we assume that relative short exposures of hcws, even if only either the worker or the patient wore a mask, probably poses a very low risk for infection. this allows us to consider performing strict follow-up of exposed hcws for symptoms, together with repeated pcr testing, instead of suspending them from work. a c c e p t e d m a n u s c r i p t figure 1 about: israeli government: ministry of health protecting chinese healthcare workers while combating the 2019 novel coronavirus saving the frontline health workforce amidst the covid-19 crisis: challenges and recommendations challenges for nhs hospitals during covid-19 epidemic universal masking in hospitals in the covid-19 era investigation of three clusters of covid-19 in singapore: implications for surveillance and response measures european centre for disease prevention and control contact tracing: public health management of persons, including healthcare workers, having had contact with covid-19 cases in the european union covid-19 guidelines, procedures and information for professionals guidance for risk assessment and work restrictions for healthcare personnel with potential exposure to covid-19 temporal dynamics in viral shedding and transmissibility of covid-19 the incubation period of coronavirus disease 2019 (covid-19) from publicly reported confirmed cases: estimation and application ministry of health, israel. covid-19 guidelines, procedures and information for professionals interim infection prevention and control recommendations for patients with suspected or confirmed coronavirus disease 2019 (covid-19) in healthcare settings proactive screening approach for sars-cov-2 among healthcare workers. clinical microbiology and infection prevalence and clinical presentation of health care workers with symptoms of coronavirus disease 2019 in 2 dutch hospitals during an early phase of the pandemic covid-2019) infection among health care workers and implications for prevention measures in a tertiary hospital in wuhan, china minnesota department of health, responding to and monitoring covid-19 exposures in health care settings individual quarantine versus active monitoring of contacts for the mitigation of covid-19: a modelling study all authors report no conflict of interest. our study does not include factors necessitating patient consent. a c c e p t e d m a n u s c r i p t a c c e p t e d m a n u s c r i p t key: cord-253833-0lajhqn5 authors: misra-hebert, anita d; jehi, lara; ji, xinge; nowacki, amy s.; gordon, steven; terpeluk, paul; chung, mina k.; mehra, reena; dell, katherine m.; pennell, nathan; hamilton, aaron; milinovich, alex; kattan, michael w.; young, james b. title: impact of the covid-19 pandemic on healthcare workers risk of infection and outcomes in a large, integrated health system. date: 2020-08-19 journal: res sq doi: 10.21203/rs.3.rs-61235/v1 sha: doc_id: 253833 cord_uid: 0lajhqn5 background: understanding the impact of the covid-19 pandemic on healthcare workers (hcw) is crucial. objective: utilizing a health system covid-19 research registry, we assessed hcw risk for covid-19 infection, hospitalization and intensive care unit (icu) admission. design: retrospective cohort study with overlap propensity score weighting. participants: individuals tested for sars-cov-2 infection in a large academic healthcare system (n=72,909) from march 8-june 9 2020 stratified by hcw and patient-facing status. main measures: sars-cov-2 test result, hospitalization, and icu admission for covid-19 infection. key results: of 72,909 individuals tested, 9.0% (551) of 6,145 hcw tested positive for sars-cov-2 compared to 6.5% (4353) of 66,764 non-hcw. the hcw were younger than non-hcw (median age 39.7 vs. 57.5, p<0.001) with more females (proportion of males 21.5 vs. 44.9%, p<0.001), higher reporting of covid-19 exposure (72 vs. 17 %, p<0.001) and fewer comorbidities. however, the overlap propensity score weighted proportions were 8.9 vs. 7.7 for hcw vs. non-hcw having a positive test with weighted odds ratio (or) 1.17, 95% confidence interval (ci) 0.99-1.38. among those testing positive, weighted proportions for hospitalization were 7.4 vs.15.9 for hcw vs. non-hcw with or of 0.42 (ci 0.26-0.66) and for icu admission: 2.2 vs.4.5 for hcw vs. non-hcw with or of 0.48 (ci 0.20 -1.04). those hcw identified as patient-facing compared to not had increased odds of a positive sars-cov-2 test (or 1.60, ci 1.08-2.39, proportions 8.6 vs. 5.5), but no statistically significant increase in hospitalization (or 0.88, ci 0.20-3.66, proportions 10.2 vs. 11.4) and icu admission (or 0.34, ci 0.01-3.97, proportions 1.8 vs. 5.2). conclusions: in a large healthcare system, hcw had similar odds for testing sars-cov-2 positive, but lower odds of hospitalization compared to non-hcw. patient-facing hcw had higher odds of a positive test. these results are key to understanding hcw risk mitigation during the covid-19 pandemic. understanding the risks associated with the covid-19 pandemic 1 on healthcare workers (hcw), including the risk of acquisition at work vs other settings, is crucial. prediction of risk can inform how to protect hcws such as recommendations on use of personal protective equipment (ppe) at work or in the community. the presence of speci c symptoms in hcw (china, us) 2,3 and symptoms predicting sars-cov-2 test positivity in hcw (netherlands) 4 have been reported as well as characteristics associated with hcw deaths (china). 5 based upon data from the 2018 national health interview survey, it was estimated that 26.6% of patient facing hcw were at increased risk for poor outcomes from covid-19 infection because of their comorbidities or age. 6 reported experiences in china 7 , italy 8 and solano county, ca without initial use of ppe 9 showed higher percentages of hcw testing positive for covid-19. in contrast, a screening study of hcw in england showed no signi cant difference in positive results between clinical and nonclinical staff with implementation of isolation and ppe protocols perhaps suggesting predominant community rather than nosocomial transmission patterns. 10 the extent of risk modi cation with ppe remains unclear. [7] [8] [9] 11 a recent prospective study in the united kingdom and us suggested a ve-fold increased risk for hcw caring for patients with covid-19 compared to hcw not caring for patients with covid-19, even with the use of ppe 12 while another study of hcw in a large healthcare system showed a decrease in positive tests for sars-cov-2 associated with a universal masking recommendation. 13 this heterogeneous landscape makes it di cult for the hcw community to determine actual risk of acquiring covid-19 in healthcare vs. community settings and the effectiveness of various risk-mitigating strategies. the cleveland clinic health system (cchs) is a large, integrated health system with 55,574 eligible employees in ohio & florida. the cchs initiated multiple covid-19 related public health initiatives to mitigate the spread of the disease and its impact on the hcw community. in parallel, we maintained a rigorous, comprehensive, and prospective registry capturing disease risk and progression in all individuals tested for covid-19 in our health system. in this study, we aimed to assess whether hcw are at higher risk for covid-19 infection, covid-19 related hospitalization, and intensive care unit (icu) admission compared to non-hcw using advanced statistical methodology to account for various confounders. cohort de nition covid-19 cleveland clinic enterprise registry: all patients, regardless of age, who were tested for covid-19 at all cchs locations in ohio and florida were included in this research registry. for this study, all individuals who were tested for covid-19 in the cchs between march 8, 2020 and june 9, 2020 were studied. this registry provides better representation of the overall population than testing restricted to one geographic health system site. registry variables were chosen to re ect available literature on covid-19 disease characterization, progression, and proposed treatments, including medications initially thought to have potential for bene t after drug-repurposing network analysis. 14 capture of detailed research data was facilitated by the creation of standardized clinical templates implemented across the healthcare system as patients were seeking care for covid-19-related concerns. data were extracted via previously validated automated feeds from electronic health records 15 (epic; epic systems corporation) and manually by a study team trained on uniform sources for the study variables. study data were collected and managed using redcap electronic data capture tools hosted at the cleveland clinic. 16, 17 the covid-19 research registry team includes a "reviewer" group and a "quality assurance" group. the reviewers were responsible for manually abstracting and entering a subset of variables that cannot be automatically extracted from the electronic health record (ehr). reviewers were also asked to verify high-priority variables that have been automatically pulled into the database from epic. the cleveland clinic institutional review board approved this study and waived the requirements for written informed consent. 21, 22 weighting was performed to address potential confounding in comparing hcw to non-hcw given their baseline differences. the overlap propensity score weighting method was chosen given its bene ts of preservation of numbers of individuals in each group and of achieving higher levels of precision in the resulting estimates. this methodology is preferred when the propensity score distributions among the groups are dissimilar and when the propensity scores are clustered near the extremes (i.e. close to zero or one). a propensity score for being a hcw was estimated from a multivariable logistic regression model. for the outcome of being test positive for covid-19, the propensity score logistic regression model included covariates that were found to be associated with a positive covid-19 test outcome in our previous work. 23 for the outcomes of hospital and intensive care unit (icu) admission of covid-19 test positive patients, the propensity score covariates are those that were found associated with covid-19 hospitalization outcome in our previous work including age, race, ethnicity, gender, smoking history, body mass index, median income, population per housing unit, presenting symptoms (including fever, fatigue, shortness of breath, diarrhea, vomiting), comorbidities (including asthma, hypertension, diabetes, immunosuppressive disease), medications (including immunosuppressive treatment, non-steroidal anti-in ammatory drugs [nsaids]), and laboratory values (including pre-testing platelets, aspartate aminotransferase, blood urea nitrogen, chloride, and potassium). the overlap propensity score weighting method was then applied where each patient's statistical weight is the probability of that patient being assigned to the opposite group. 21 overlap propensity score weighted logistic regression models were used to investigate associations between hcw status and the probability of testing positive for sars-cov-2, hospital admission for covid-19 and icu admission for covid-19 illness. the results are thus reported as weighted proportions, odds ratios and 95% con dence intervals. all statistical analyses were performed using r 3.5 and sas version 9.4 (sas institute). p values were 2-sided, with a signi cance threshold of .05. we then used locally weighted regression smoother (loess) to summarize the trend of covid-19 test positivity through the study period for hcw and non-hcw as related to the public health measures instituted at the state level in ohio and those speci c to the cchs. overall covid-19 cohort characteristics and outcomes: there were 551 hcw and 4,353 non-hcw who tested positive for covid-19 (appendix table 2 ). of those who tested positive for covid-19, a lower proportion of hcw were hospitalized compared to non-hcw (38 or 6.9% hcw vs. 1205 or 27.7% non-hcw) or were admitted to the intensive care unit (10 or 1.8% hcw vs. 470 or 10.8% non-hcw). in the group who tested positive for covid-19, there was a greater proportion of hcw of asian and white race compared to non-hcw (2.9 vs. 0.8% and 61.0 vs 56.4%, respectively), a similar proportion of hcw with a positive covid-19 test had presenting symptoms of cough, fatigue, diarrhea, loss of appetite, and vomiting and a lower proportion had fever or shortness of breath. lower proportions of hcw testing positive had copd/emphysema, diabetes, coronary artery disease, heart failure, cancer, or immunosuppressive disease and were previously prescribed carvedilol, angiotensin converting enzyme inhibitors, angiotensin receptor blockers or melatonin compared to non-hcw. the neighborhood population characteristics of population density or population per housing unit did not differ for those hcw who tested positive and median income was slightly higher compared to non-hcw. overlap propensity weighting: using the variables in the prediction model for covid-19 test positivity, 23 overlap propensity score weighting ( table 2 ) resulted in propensity score weighted proportions of 7.7 vs. 8.9 for non-hcw vs. hcw having a positive test and produced an overlap propensity score weighted odds ratio of 1.17 with a 95% con dence interval (ci) of 0.99-1.38 for a hcw having a positive test compared to a non-hcw (figure 1a ). then using the variables which predicted hospitalization for covid-19 infection, overlap propensity score weighting was applied ( (figure 1a ). we then compared characteristics of hcw identi ed as having positions that required direct contact with patients ("patient facing") and those that did not. there were 5,159 hcw with patient-facing positions and 986 hcw in non-patient facing roles (appendix table 3 the summary of the trend of sars-cov-2 positive test results in the study period is shown in figure 2 . the overall proportion of positive covid-19 test results decreased during the study period and the trend for hcw and followed that of non-hcw. our analysis of hcw compared to non-hcw who were tested for sars-cov-2 in one health system with 2 geographic locations (ohio, florida), and which controlled for signi cant differences in baseline characteristics between the hcw and non-hcw groups, showed that the odds of having a positive covid-19 test were not signi cantly different for hcw compared to non-hcw, and hcw had lower odds of subsequent hospitalization, and without statistically signi cant differences in icu admission compared to non-hcw once they tested positive. the hcw classi ed as having patient-facing positions had higher and signi cant odds of a positive covid-19 test with insigni cant differences detected compared to nonpatient facing hcw in outcomes of hospitalization or icu admission. we found a similar proportion of hcw with a positive covid-19 test had presenting symptoms of cough, fatigue, diarrhea, loss of appetite, and vomiting while a lower proportion had fever or shortness of breath. we note that we were not able to capture the symptoms of loss of taste and/or smell and that these symptoms may be common especially with mild cases of covid-19. 24, 25 the overall proportion of covid-19 positive tests in hcw was low and decreased during the study period corresponding with implementation of risk-mitigation measures in our health system such as the recommendations for universal masking and physical distancing but also followed the trend for non-hcw. several of the previous studies of hcw risk for infection during the covid-19 pandemic were limited by their sample sizes, 7-9 lack of generalizability for healthcare systems that have adequate access to ppe, 7-9 methodology relying on self-report, 12 limited ability to adjust for known risk factors of disease susceptibility and progression [7] [8] [9] [10] 12 and lacking data to investigate the relative effects of dual exposure of hcw to covid-19 in the community versus the workplace. [7] [8] [9] [10] 12 the fact that hcw identi ed as patient-facing had a signi cantly higher odds for sars-cov-2 test positivity suggests an increased risk of covid-19 infection with work exposure. however, it is important to note in our study that that over 70% of the hcw group reported an exposure to covid-19 with 28% reporting exposure to a family member with covid-19. in our study, we were not able to con rm if the patient-facing hcw were working in patient-facing areas the 14-day period before the test was ordered when exposure could have occurred, or whether the exposure occurred with or without ppe -both in the workplace or in the community, or the relative contribution of initially prioritizing testing availability to hcw with reported exposures. while the risk to hcw attributed to community spread may not be captured in our available data, the reported exposure risk including the higher proportion of hcw vs. non-hcw reporting exposure to a family member with covid-19 suggests a degree of community acquisition of infection. a potential contributing factor to community acquisition is that hcws, particularly patient-facing hcw, are less able to follow stay-at-home guidelines or work remotely from home. indeed, while ppe use is associated with decrease risk of infection from coronavirus, 26 a recent report estimated less than 5% risk to hcw inadvertently exposed to patients not known to be sars-cov-2-positive at the time of initial exposure with exposure likely occurring without appropriate ppe 27 suggesting that the work exposure risk may actually be low. however, universal pandemic precautions have been recommended for optimal risk mitigation for hcw. 28 in our analysis of one healthcare system which implemented signi cant risk mitigation strategies to prevent the spread of covid-19 infection, and which controlled for signi cant baseline differences in hcw compared to non-hcw, the odds for sars-cov-2 infection were similar for hcw and non-hcw and hcw had lower odds for covid-19 related hospitalization .the patient facing hcw had higher odds of sars-cov-2 infection. centers for disease control and prevention clinical characteristics of 80 hospitalized frontline medical workers infected with covid-19 in wuhan characteristics of health care personnel with covid-19 -united states strong associations and moderate predictive value of early symptoms for sars-cov-2 test positivity among healthcare workers, the netherlands characteristics of deaths amongst health workers in china during the outbreak of covid-19 infection health insurance status and risk factors for poor outcomes with covid-19 among u.s. health care workers: a cross-sectional study characteristics of and important lessons from the coronavirus disease 2019 (covid-19) outbreak in china: summary of a report of 72 314 cases from the chinese center for disease control and prevention covid-19: the daunting experience of health workers in transmission of covid-19 to health care personnel during exposures to a hospitalized patient first experience of covid-19 screening of health-care workers in england masks for prevention of respiratory virus infections, including sars-cov-2, in health care and community settings risk of covid-19 among frontline healthcare workers and the general community: a prospective cohort study association between universal masking in a health care system and sars-cov-2 positivity among health care workers network-based drug repurposing for novel coronavirus 2019-ncov/sars-cov-2 | cell discovery. accessed extracting and utilizing electronic health data from epic for research research electronic data capture (redcap)--a metadata-driven methodology and work ow process for providing translational research informatics support department of health covid-19 outbreak the state of florida issues covid-19 updates | florida department of health addressing extreme propensity scores via the overlap weights understanding observational treatment comparisons in the setting of coronavirus disease 2019 (covid-19) individualizing risk prediction for positive covid-19 testing: results from 11,672 patients loss of taste and smell as distinguishing symptoms of covid-19 evolution of altered sense of smell or taste in patients with mildly symptomatic covid-19. jama otolaryngol--head neck surg epidemiology of and risk factors for coronavirus infection in health care workers covid-19 infections among hcws exposed to a patient with a delayed diagnosis of covid-19 universal pandemic precautions-an idea ripe for the times the authors report no con ict of interest related to this work.dr. misra-hebert receives funding from the agency for healthcare research and quality grant # k08hs024128 and reports grants from nhlbi, grants from novo nordisk, inc, grants from merck inc., key: cord-325778-y5miy24f authors: quigley, ashley l.; stone, haley; nguyen, phi yen; chughtai, abrar ahmad; macintyre, c. raina title: estimating the burden of covid-19 on the australian healthcare workers and health system date: 2020-10-29 journal: int j nurs stud doi: 10.1016/j.ijnurstu.2020.103811 sha: doc_id: 325778 cord_uid: y5miy24f introduction: there is no publicly available national data on healthcare worker infections in australia. it has been documented in many countries that healthcare workers are at increased occupational risk of covid-19. we aimed to estimate the burden of covid-19 on australia healthcare workers and the health system by obtaining and organizing data on hcw infections, analyzing national hcw cases in regards to occupational risk and analyzing healthcare outbreak. methods: we searched government reports and websites and media reports to create a comprehensive line listing of australian healthcare worker infections and nosocomial outbreaks between january 25(th) and july 8(th), 2020. a line list of healthcare worker related covid-19 reported cases was created and enhanced by matching data extracted from media reports of healthcare related covid-19 relevant outbreaks and reports, using matching criteria. rates of infections and odds ratios (ors) for healthcare workers were calculated per state, by comparing overall cases to healthcare worker cases. to investigate the sources of infection amongst healthcare workers, transmission data were collated and graphed to show distribution of sources. results: we identified 36 hospital outbreaks or outbreaks between january 25(th) and july 8(th), 2020. according to our estimates, at least 536 healthcare workers in australia have been infected with covid-19, comprising 6.03% of all reported infections. the rate of healthcare worker infection was 72/100,000 and of community infection 34/100,000. healthcare workers were 2.76 times more likely to contract covid-19 (95% ci 2.53 to 3.01; p<0.001). the timing of hospital outbreaks did not always correspond to community peaks. where data were available, a total of 131 healthcare workers across 21 outbreaks, led to 1656 healthcare workers being furloughed for quarantine. one hospital was closed and had 1200 workers quarantined in one outbreak. conclusion: the study shows that hcws were at nearly 3 times the risk of infection. of concern, this nearly tripling of risk occurred during a period of low community prevalence suggesting failures at multiple hazard levels including ppe policies within the work environment. even in a country with relatively good control of covid-19, healthcare workers are at greater risk of infection than the general community and nosocomial outbreaks can have substantial effects on workforce capacity by the quarantine of numerous workers during an outbreak. the occurrence of hospital outbreaks even when community incidence was low, highlights the high risk setting that hospitals present. australia faces a resurgence of covid-19 since late june 2020, with multiple hospital outbreaks. we recommend formal reporting of healthcare worker infections, testing protocols for nosocomial outbreaks, cohorting of workforce to minimize the impact, and improved ppe guidelines to provide precautionary and optimal protection for healthcare workers. 131 healthcare workers across 21 outbreaks, led to 1656 healthcare workers being furloughed for quarantine. one hospital was closed and had 1200 workers quarantined in one outbreak. the study shows that hcws were at nearly 3 times the risk of infection. of concern, this nearly tripling of risk occurred during a period of low community prevalence suggesting failures at multiple hazard levels including ppe policies within the work environment. even in a country with relatively good control of covid-19, healthcare workers are at greater risk of infection than the general community and nosocomial outbreaks can have substantial effects on workforce capacity by the quarantine of numerous workers during an outbreak. the occurrence of hospital outbreaks even when community incidence was low, highlights the high risk setting that hospitals present. australia faces a resurgence of covid-19 since late june 2020, with multiple hospital outbreaks. we recommend formal reporting of healthcare worker infections, testing protocols for nosocomial outbreaks, cohorting of workforce to minimize the impact, and improved ppe guidelines to provide precautionary and optimal protection for healthcare workers. what is already known about this topic:  the absence of formal national reporting of hcw infections makes it difficult to inform work health and safety of hcw. as of 11 th july, over 12 million cases of covid-19 have been confirmed worldwide, causing more than 548,000 deaths 3 , with global covid-19 healthcare worker (hcw) infections on the rise. by early march 2020, more than 3300 hcw had been infected in china alone, with reports of at least 22 hcw deaths 4 . in italy, a country with a high burden of covid-19, over 20% of responding hcw have been infected, with almost 200 hcw deaths 5, 6 . the international council of nurses (icn) has reported that more than 600 nurses have died in the covid-19 pandemic and estimate that over 450,000 hcw had been infected by june 3 rd , 2020 7 . the number of global hcw infections may be underreported due to many countries state health departments not tracking deaths and infections by occupation 8 . the precise dynamics of transmission of covid-19 is unknown, but likely through a combination of droplets, aerosols and contact 9, 10 . frontline hcws, such as those working in emergency wards are at increased risk as hcw are often exposed to patients with high viral loads whilst providing care 11 and accumulated respiratory aerosols in the work-place may pose a risk to occupational safety. hospitals are highly contaminated environments 11 and hazard controls including ppe are often compromised.. in the uk, where testing was done in two national health system (nhs) trusts, almost one in five hcw were infected 12, 13 . therefore, given the hospital as a site of potential outbreaks, infected hcw may be asymptomatic or presymptomatic, and unknowingly infect others at work. a study of hcw infections in wuhan, china, found that the case infection rate of hcw was 2.0%, significantly higher than non-hcw at 0.43% 14 . an analysis of the covid-19 hcw infections in china during the initial phase of the outbreak, found that a high number of hcw cases occurred through contact with asymptomatic patients or mildly symptomatic patients of covid-19 and through direct contact between hcw 15 . a surgical patient in a wuhan hospital infected 14 hcw before fever onset 16 . hcw may therefore unknowingly acquire and transmit infections to patients and other hcw around them. many studies have also shown that hospitals not only present a high exposure setting for respiratory infections in hcw 17, 18 but that presenteeism is a key risk factor in disease transmission and extension of an outbreak 19 . an employee who attends work regardless of having a medical illness which prevents them from functioning optimally, demonstrates presenteesim 19 . despite the serious public health risks of presenteeism 20 , hcw have been identified as a group that are very likely to continue to work when infected with diseases such as influenza and norovirus 21 . in addition, asymptomatic or pre-symptomatic infection can result in nosocomial outbreaks as hcw may work without realizing they are infected. shortages of personal protective equipment (ppe) have been described as a contributing risk factor for covid-19 in hcw worldwide 5, 22, 23 . initial recommendations from the centres for disease control and prevention (cdc) were to use respirators, but following a shortage in supply of these, guidelines changed to the use of medical masks, or even cloth masks 24, 25 27 . further to this, there is always the concern of the risk that demand could outweigh supply of hcw in hotspots that emerge during peaks in the pandemic 28 . whilst covid-19 hcw infections have been estimated at greater than over 19 000 cases in the united states of america and over 150 000 cases in europe 1,2,12,13 , in the absence of national reporting of hcw infections, the impact of covid-19 on hcw in australia needs to be investigated 12, 13 . the aim of the study was to estimate the burden of covid-19 on australian hcw and the national health system using publicly available data. although there is no national reporting of hcw infections, daily press releases from government sources and media reports have reported on hospital outbreaks and hcw infections. we collected publicly available data on australian covid-19 patients reported by national and state/territory governments and the media between january 25 th , 2020 and july 8 th , 2020. hcw for the line list of outbreaks where an outbreak is defined as 2 or more cases of covid-19 in a one week period, outbreak information was matched using date, location (state/territory and city), the name of the clinical facility, number of cases, patient age, number of deaths and occupation as an hcw. matching criteria were used to match information from the media to relevant outbreaks and reports. matched outbreaks included in this report were detailed in state media releases and thus were recorded in the line list. hcw cases from media reports were matched with hcw cases recorded in the line list based on the matching criteria matrix in table 1 . a case is considered a high probability match if fulfilling at least one criterion from all groups (1, 2 and 3); a medium probability match if fulfilling at least one criterion from groups 2 and 3; and otherwise a low probability match. only cases with high probability matching were included for the line list and analysis. for the purposes of this study, clinical facilities were deidentified in reporting the results. rates of infections for hcw were calculated using reported cases and the remaining total cases as the numerator, and denominator data was obtained from the australian government 42 outbreak in melbourne has also seen a rise in hcw infections since late june 2020. out of 36 hospital outbreaks identified from the media, 2 (5.56%) started with a hcw that travelled interstate; 2 (5.56%) started with a hcw that returned from overseas; 4 (11.11%) started with a hcw that was a contact of a known case from a communityoutbreak; 5 (13.89%) were traced to contact with a patient that tested positive for covid-19, and 22 (61.11%) did not have information to determine the source of infection. based on the setting in which the first hcw case was working on when they acquired coviddescriptive information for hcw outbreaks is outlined in table 3 in the appendix. one way to measure the burden of covid-19 infections on the health system is to measure the ratio of the number of hcw being quarantined because of contact with a known case, to the number of positive cases. facilities or wards were not shut down. the factors that might explain the disparity in the ratios include the type of acute care facilities such as emergency departments which may not be able to be shut down and availability of hcw to replace those in quarantine. in the absence of formally reported statistics on hcw infections, we estimated 536 hcw infections up to july 2020, and that hcw account for 6.03% of covid-19 infections in australia and have double the risk of contracting covid-19 than the general community. the numbers we estimate are consistent with federal government press releases that there were 481 hcw infections by april 2020, released well after national cases had significantly decreased 59 . the higher risk of infection is consistent with studies overseas which show a higher risk for hcw 12, 13 . a potential limitation of the risk analyses conducted for this study were based on open-sourced data for hcw cases, which may vary depending on each state's individual data publishing policies. we also used media reports, which have not been verified. in most cases, however, there were multiple media reports about each outbreak, often with quotes from health officials. there is also a potential effect of testing rates on the identification of covid-19 cases. we accounted for this by representing the daily testing rates in conjunction with the daily hcw infections reported. the source of infection for 22 of the 36 outbreaks analyzed could not be identified. the occupational risk level for the 36 outbreaks is therefore uncertain. the study did not include a second wave of covid-19 which occurred in the state of victoria in june-july 2020, where over 3000 hcw were infected 60, 61 . therefore, this study may not be generalizable to the period july-august 2020. it may not be generalizable to other countries or settings, with different covid-19 epidemiology and health systems. nosocomial outbreaks of sars and sars-cov-2 have been described 62 , showing hospitals to be a high risk setting for outbreaks. hcw may become infected from covid-19 patients, coworkers or from outside the hospital, and may act as vectors for onward transmission to coworkers, patients and community members including household contacts. there are some hcws who have continued to work while symptomatic and some may be asymptomatically infected and working. our analysis shows that the source of hospital outbreaks can be from both covid-19 patients and from infections imported into the hospital by hcw or others. undiagnosed covid-19 patients 63 or undiagnosed hcw may both cause transmission in the hospital setting. the largest covid-19 hcw outbreak occurred during the first few weeks of the australian pandemic when community transmission was low and testing of hcw was based on symptoms. infection and mortality of healthcare workers worldwide from covid-19: a scoping review european public service union. health workers bear brunt of covid-19 infections world health organization. coronavirus disease 2019. world health organization death from covid-19 of 23 health care workers in china deaths from covid-19 in healthcare workers in italy -what can we learn? covid-19: protecting health-care workers more than 600 nurses die from covid-19 worldwide nearly half a million health care workers worldwide infected with coronavirus a familial cluster of pneumonia associated with the 2019 novel coronavirus indicating person-to-person transmission: a study of a family cluster it is time to address airborne transmission of covid-19 aerosol and surface transmission potential of sars-cov-2. medrxiv first experience of covid-19 screening of healthcare workers in england roll-out of sars-cov-2 testing for healthcare workers at a large nhs foundation trust in the united kingdom analysis of the infection status of the health care workers in wuhan during the covid-19 outbreak: a cross-sectional study avoiding health worker infection and containing the coronavirus disease 2019 pandemic: perspectives from the frontline in wuhan world health organization; who. novel coronavirus (2019-ncov) 22 viral and bacterial upper respiratory tract infection in hospital health care workers over time and association with symptoms quantifying the risk of respiratory infection in healthcare workers performing high-risk procedures presenteeism: a public health hazard australian government department of health. personal protective equipment (ppe) for the health workforce during covid-19. coronavirus (covid-19) health alert 19-advice-for-the-health-and-disability-sector/personal-protectiveequipment-ppe-for-the-health-workforce-during-covid-19 effectiveness of cloth masks for protection against severe acute respiratory syndrome coronavirus 2 center for disease control and prevention. strategies for optimizing the supply of facemasks: covid-19 | cdc deeply concerned": doctor at melbourne hospital tests positive to coronavirus. the age doctors "bullied" by hospital administration for asking to wear masks coronavirus. the sydney morning herald covid-19) current situation and case numbers queensland covid-19 statistics government of western australia department of health. coronavirus covid-19 in western australia the situation report government of south australia. testing for covid-19: who can get tested nsw department of health. covid-19 (coronavirus) statistics more than 120 doctors and staff quarantined, but worst to come fears of cairns cluster after 5 hospital lab workers test positive ruby princess" hospital hit by covid-19 outbreak warned of melbourne-cedar-meats-outbreak-rises-to-45 australian healthcare workers riding the coronavirus curve are relieved as infections dwindle victorian healthcare worker coronavirus (covid -19) data. latest news and data a hospital-wide response to multiple outbreaks of covid-19 in health care workers lessons learned from the field covid-19 and the risk to health care workers: a case report current guidelines for respiratory protection of australian health care workers against covid-19 are not adequate and national reporting of health worker infections is required australian government department of health. coronavirus disease 2019 (covid-19) -cdna national guidelines for public health units 2584f8001f91e2/$file/covid-19-song-v3.4.pdf. published 2020 fewer than one in 50 nhs frontline staff forced to stay at home have been tested. the independent covid-19: the case for health-care worker screening to prevent hospital transmission cdc covid-19 response team. characteristics of health care personnel with covid-19 transmission of 2019-ncov infection from an asymptomatic contact in germany prevalence of asymptomatic sars-cov-2 infection estimating the extent of true asymptomatic covid-19 and its potential for community transmission: systematic review and meta-analysis epidemiology of and risk factors for coronavirus infection in health care workers guidance on the use of personal protective equipment (ppe) in hospitals during the covid-19 outbreak detection of air and surface contamination by 77. guardian staff. australia's coronavirus victims: covid-19 related deaths across the country coronavirus cluster at melbourne hospital sends 100 staff into self-isolation key points government of western australia department of health. covid-19 update -29 coronavirus fears for kimberley as two more healthcare workers test positive for covid-19 ten workers at nepean and sydney adventist hospitals quarantined accessed royal adelaide hospital nurse tests positive to coronavirus sydney midwife at st george hospital tests positive for covid-19 coronavirus crisis: st john of god subiaco surgeon tests positive to covid-19 park royal hotel melbourne health worker positive for covid healthcare worker among victoria's new covid cases as more schools shut eight coronavirus cases at northern hospital emergency department in brunswick private hospital in melbourne records five coronavirus cases ambulance victoria confirms two paramedics have tested positive to coronavirus tasmania closes two hospitals to "stamp out" coronavirus outbreak in the north-west key points. abc news key: cord-286932-2gjnpqqa authors: lee, yung; kirubarajan, abirami; patro, nivedh; soon, melissa sam; doumouras, aristithes g.; hong, dennis title: impact of hospital lockdown secondary to covid-19 and past pandemics on surgical practice: a living rapid systematic review date: 2020-11-12 journal: am j surg doi: 10.1016/j.amjsurg.2020.11.019 sha: doc_id: 286932 cord_uid: 2gjnpqqa background: the covid-19 pandemic has disrupted surgical practice worldwide. there is widespread concern for surgeon and provider safety, and the implications of hospital lockdown on patient care during epidemics. methods: medline, embase, central, and pubmed were systematically searched from database inception to july 1, 2020 and ongoing monthly surveillance will be conducted. we included studies that assessed postoperative patient outcomes or protection measures for surgical personnel during epidemics. results: we included 61 studies relevant to the covid-19 pandemic and past epidemics. lockdown measures were noted globally including cancellation of elective surgeries and outpatient clinics. the pooled postoperative complication rate during epidemics was 21.0% among 2095 surgeries. 31 studies followed the health of surgical workers with the majority noting no adverse outcomes with proper safety measures. conclusions: this review highlights postoperative patient outcomes during worldwide epidemics including the covid-19 pandemic and identifies specific safety measures to minimize infection of healthcare workers. the current covid-19 pandemic has disrupted health services worldwide. 1, 2 there is a concern of nosocomial transmission, shortage of personal protective equipment (ppe), and limited resources for critical patients. [3] [4] [5] [6] as a result, many hospitals have undergone lockdown procedures in which staffing and services are limited. these lockdown procedures have inconsistent policies, often occurring on an urgent basis with little notice or preparation. in previous outbreaks such as severe acute respiratory syndrome (sars) and ebola, these precautionary measures have lasted several months with downstream effects on health outcomes. 7, 8 surgical practice is particularly at risk for lockdowns during outbreaks and epidemics. 9 in particular, there may be a heightened risk for transmission of airborne pathogens during aerosolizing procedures in laparoscopic surgeries, though current evidence is unclear. in addition, there is risk of transmission of blood-borne viruses such as ebola during accidental injuries. 9, 10 operation techniques and equipment management may also be altered to reduce contact with potential vectors. 9 in addition, intensive care units and emergency departments are often overwhelmed with critical care patients, with a limited supply of ventilators and bedspace. 4 as such, the centers for disease control and prevention recently published an interim surveillance was carried out until may 29, 2020. the search strategy (see appendix 1) was designed in consultation with a medical librarian. this systematic review is reported in accordance with the preferred reporting items for systematic reviews and meta-analyses (prisma), with the prisma flow diagram presented in figure 1 . 13 studies reporting outcomes of patients undergoing surgery during an epidemic-caused hospital lockdown and studies investigating the impact of lockdown on surgical hcw and surgical practice were included. articles were excluded from our review if they (1) were a review article, case report, letter to the editor, opinion, commentary, or editorial (2) did not contain at least one relevant outcome of interest (3) investigated a lockdown caused by a local hospital outbreak. no language or geographical restrictions were applied. titles, abstracts, and full-text citations were screened, and conflict was resolved by the third reviewer. two investigators extracted study data using a standardized spreadsheet, and verification of the extracted data was carried out by a third investigator. the following variables were abstracted from the included studies: study characteristics (e.g. author, year of publication, study design, study duration, country, type of epidemic, type of institution), patient demographics (e.g. number of patients included, age, sex), and study outcomes. surgical outcomes were reported using the 34 retrospective studies, 16 case series, 5 descriptive studies, and 6 prospective studies represented a combined 3948 patients across 17 countries up to june 2020 (table 1) . studies conducted during covid-19 accounted for 98.6% of the included patients, while 1.2% were from studies during sars, and 0.15% were from studies during mers. among papers describing patient demographics, 53.9% were female and median age was 62.0 years (range 1 -100 years). a total of 455 health care workers were also represented with 70.1% hcw included during covid-19, 28.1% included during sars, and 1.8% included during ebola epidemics. hospital lockdown measures were described in 26 studies ( table 2 ). the most common measures included cancelation of elective surgery as specified in 84.6% of those studies, and a reduction or cancellation altogether of outpatient clinics specified in 23.1% of studies. one study reported stopping all planned activities to convert its centre into a dedicated covid-19 hospital. 21 another study described a mers outbreak resulting from an index case admitted to the cardiac surgery ward with no specific precautions described. 22 none of the included studies reported complete stoppage of educational activities to focus solely on patient care, as reflected by the acgme staging system scores. complication rate of 14.5% among studies reporting on complications. the most common complications included death accounting for 41.9% of complications and post-procedural bleeding accounting for 29.0%. as described above for surgical complications, multiple complications may have been reported following a single procedure. seven studies (11.5%; 7/61) reported active outpatient clinics during epidemics, though there was an overall reduction of clinic volume by 50% to 75%. eight studies, all during the covid-19 epidemics, also reported the use of telemedicine and virtual care modalities for outpatient consults and follow-up appointments. 26-34 measures to protect surgical personnel during outbreaks were reported in 45 studies (see table 4 ; detailed overview provided in supplementary table 1 ). for the purpose of analysis, protection measures were classified into one of the following categories: ppe (any form of physical protection used by hcw); pre-or (any precautions taken preoperatively including modified patient screening and disinfection processes); or setup (measures taken during surgical intervention, such as the use of negative-pressure or segregated ors); and logistics (all other measures including modification of work areas, modification of procedures, new hospital protocols and processes, and limitation/modification of hcw roles to help limit and prevent nosocomial disease transmission). modified peri-operative logistics were reported in 40 studies describing protection measures. examples of workspace modifications as described in 20 studies included establishing ultrasound workstations in areas managing infected patients to perform point-of-care lung imaging, having a designated corner in a dialysis unit for the treatment of patients who were j o u r n a l p r e -p r o o f suspected/confirmed infected, and designating doctors' and nurses' workstations as the "clean" area of a ward while other areas were considered contaminated. 21,30,35 procedural and management modification for the purpose of minimizing exposure risk was reported in 25 studies and included measures such as slowing the speed of drilling intra-operatively in neurosurgical procedures, favoring use of percutaneous drainage over ercp where possible for biliary drainage, and temporarily turning off mechanical ventilation during tracheal incision. [35] [36] [37] modified hospital rules, protocols and patient transfer processes were described in 26 studies and included limiting or preventing visitations for patients, transferring patients between the ward and or in a negative-pressure isolation transfer cabin, and use of designated transfer "lanes" between sections of the hospital to limit nosocomial spread. 23,29,35 fourteen studies described modifying the roles of hcw during epidemics, including formation of an "emergency incident command team" to identify and separate infected patients from other patients, allowing only essential personnel to be present during procedures, and assigning staff to conduct patient screening full-time. 30 modification of or setup to reduce infectious exposure risk was noted in 17 studies describing protection measures. the most common modifications included use of a negativepressure or for patients suspected or confirmed to be infected, as reported in 10 of these studies. other measures included geographically segregating or complexes to reduce cross-infection, reducing humidity level and temperature of ors to reduce hcw perspiration, and using plastic drapes around the tracheostomy operative field to create a closed sterile environment. 40, 42, 43 a summary of protection measures is provided in table 4 . all studies which implemented more than 3 of the listed measures and also reported on hcw outcomes had an infection rate of 0% among hcw. (23/269) of hcw were infected. the other two infections among hcw occurred during the ebola epidemics, where 25% (2/8) contracted the illness. both of these hcw had died from the illness and were the only instances of death reported among the 405 hcw included in this review. one study did report the death of a nurse in its traumatology department during covid-19, though the total number of hcw in the department was not specified and this instance was not captured in the pooled analysis. 21 no infections or adverse outcomes were reported for hcw during the sars epidemics (0/128) from the included studies. the rate of hcw infection based on the number of surgeries performed was 3.61% (41 hcw/1136 surgeries) among studies that reported both the number of hcw infected, and the number of surgeries conducted. one hcw was infected for every 27.7 operations performed. among studies during the covid-19 pandemic, the hcw infection rate was 3.92% (39 hcw/995 surgeries) and one hcw was infected for every 25.5 operations performed. the methodological index for non-randomized studies (minors) was used to assess risk of bias in the included studies (supplementary table 2 ). 56 studies included in this review were non-comparative with a mean global score of 10.2 (sd 1.7), indicating fair methodological quality. 16 all 56 studies had a clearly stated aim and a loss to follow-up of less than 5% (56/56). the majority of the studies adequately included consecutive patients (45/56), had adequate endpoints in relation to the stated aims (42/56), and had an appropriate follow-up period (44/56). one study adequately conducted a prospective calculation of study size (1/56). the remaining 5 studies included in this study were comparative studies with a mean global score of 14 (sd 2.9). two of these studies had adequate control groups, 2 had adequate baseline equivalence of groups, and 3 had adequate statistic calculations. prospective collection of data was reported in 7 studies (7/61). adequately unbiased assessments of study endpoints were found in 7 studies (7/61). as such, there remain significant evidence gaps for health systems to implement evidence-based surgical care during epidemics. overall, our findings contribute to the growing literature on surgical care during the current covid-19 pandemic. 44 the worldwide shortages in ppe as well as the numerous cases of hcw infection have highlighted the importance of infection control, which has been outlined in our review. 44 in addition, as the novel coronavirus can be transmitted via aerosol particles, there is particular risk of exposure during certain procedures such as endoscopy. our review outlines potential strategies that have been used to mitigate risk in previous outbreaks, such as the use of negative pressure ors for intubation. there is also concern for triaging surgical oncology cases, due to preliminary evidence that covid-19 is dangerous for patients for cancer. 45,46 as a result, the american college of surgeons has released recommendations for both the triage of non-emergent surgical procedures as well as recommendations for management of elective procedures. 47,48 many of their guidelines, such as the limitation of non-essential visitors, were similar to the strategies reported in our included studies. the american college of surgeons especially stresses the importance of ppe, which was highlighted in the included studies that discussed infection control. however, while the american college of surgeons recommends the postponement of elective surgeries, this systematic review demonstrates that there is a lack of long-term evidence regarding the potential impact on patient outcomes, particularly patient morbidity and mortality due to cancellations. 47 of note, our review also found that the overall complication rate did not j o u r n a l p r e -p r o o f seem to be increased based on the distribution of elective and emergency cases, as any association with elective surgeries is most likely due to the volume of patients rather than the distribution. in addition, while the american college of surgeons has oncology-specific guidelines regarding deferral of surgeries and guidelines for multidisciplinary care, more pandemic-specific research is required to substantiate recommendations. 49 of the included studies, 8 reported on postoperative outcomes following cancer surgeries. none of these studies examined oncology-related outcomes, such as remission rates or changes to chemotherapy cycles. in addition, none of the included studies analyzed the motivations of surgeons to continue working during epidemics. during the covid-19 pandemic, there has been increasing concern regarding hcw absenteeism and willingness to work in hazardous environments, particularly due to shortages in ppe. previous literature has demonstrated that perceived personal safety was a large factor in whether hcw continue to practice during the previous sars and influenza outbreaks. 50, 51 as our review outlines several strategies to protect surgical hcw, implementation could be useful in alleviating the anxieties of hcw and encourage frontline practice. finally, we did not review the impact of covid-19 on surgical graduate medical education, which is an emerging area of concern. there is growing evidence that surgical residencies and postgraduate medical education has been significantly impacted by the covid-19 pandemic. [52] [53] [54] literature has suggested that residents have decreased opportunity to participate in surgical cases. similarly, one of our included studies noted that operations were more likely to be performed by staff surgeons in comparison to trainees during epidemics. this may be due to university-based safety guidelines, the redirection of trainees to other specialties, j o u r n a l p r e -p r o o f as well as reduced surgical volume. technological options such as virtual curriculums and simulations have been posed in the interim to maintain the education of surgical residents. 55 the main limitation of our systematic review is the lack of published research on surgical care during epidemics. due to the unpredictable and demanding nature of epidemics, it is often difficult for physicians to prioritize research while in the midst of disease outbreaks. this significantly limits the ability to collect prospective information. as such, much of the available literature was limited to case series and smaller scale retrospective reviews. in addition, considerations from previous pandemics may not necessarily translate to relevance for the covid-19 pandemic or any future epidemics. the included studies have diverse health systems and delivery models, which reduce generalizability of considerations such as infection control and lockdown guidelines. this is especially relevant for low-resourced health systems, which may face additional shortages. another limitation of our review is that we were unable to stratify our results in terms of lockdown measures taken, given that this information was reported in fewer than half of the included studies. we are therefore unable to comment on the impact of specific lockdown measures on patient and hcw outcomes. ultimately, it is often difficult for institutions to balance providing timely surgical care while ensuring safety during epidemics. while lockdown precautions have been used in previous outbreaks, it is unclear how the reduced access to surgical care will affect patient care in the long-term. in addition, it is unclear how to prioritize surgical care when lockdown precautions are eventually lifted. future research should analyze the impact of covid-19 on surgical waittimes and related complications, as well as patient and provider satisfaction. in the meantime, institutions should cooperate with policymakers to determine best precautions for surgical care. surgical practice during epidemics affects all levels of the hospital, from creating a new demand j o u r n a l p r e -p r o o f on ppe to alleviating burden within the emergency department. as such, decisions regarding surgical care during epidemics should not occur in isolation from other medical specialties. this research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. a novel coronavirus from patients with pneumonia in china fair allocation of scarce medical resources in the time of covid-19 world health organization. shortage of personal protective equipment endangering health workers worldwide the toughest triage -allocating ventilators in a pandemic early transmission dynamics in wuhan, china, of novel coronavirus-infected pneumonia protecting health care workers during the covid-19 coronavirus outbreak -lessons from taiwan's sars response can we contain the covid-19 outbreak with the operation ebola: surgical care during the west african oubreak guidance for risk assessment and work restrictions for healthcare personnel with potential exposure to covid-19 | cdc 2019-ncov's epidemic in middle province of northern italy: impact, logistic & strategy in the first line hospital preferred reporting items for systematic reviews and meta-analyses: the prisma statement the clavien-dindo classification of surgical complications: five-year experience three stages of gme during the covid-19 pandemic. accreditation council for graduate medical education cancer surgery cases during the acute and recovery phases of coronavirus disease 2019 (covid-19) pandemic survey of hospital healthcare personnel severe acute respiratory syndrome (sars) in hong kong in 2003: stress and psychological impact among frontline healthcare workers clinic akron general urology residency program's covid-19 experience residency and fellowship program accreditation: effects of the novel coronavirus (covid-19) pandemic emergency restructuring of a general surgery residency program during the coronavirus disease 2019 pandemic: the university of washington experience using technology to maintain the education of residents during the covid-19 pandemic sars-cov-1.mp sars-cov-2.mp the authors declare no conflict of interest.j o u r n a l p r e -p r o o f feb to apr 2020 covid-19 covid-19 â�� â�� covid-19 covid-19 â�� â�� covid-19 covid-19 key: cord-336837-rerp1g1w authors: jones, nick k; rivett, lucy; sparkes, dominic; forrest, sally; sridhar, sushmita; young, jamie; pereira-dias, joana; cormie, claire; gill, harmeet; reynolds, nicola; wantoch, michelle; routledge, matthew; warne, ben; levy, jack; córdova jiménez, william david; samad, fathima nisha begum; mcnicholas, chris; ferris, mark; gray, jane; gill, michael; curran, martin d; fuller, stewart; chaudhry, afzal; shaw, ashley; bradley, john r; hannon, gregory j; goodfellow, ian g; dougan, gordon; smith, kenneth gc; lehner, paul j; wright, giles; matheson, nicholas j; baker, stephen; weekes, michael p title: effective control of sars-cov-2 transmission between healthcare workers during a period of diminished community prevalence of covid-19 date: 2020-06-19 journal: elife doi: 10.7554/elife.59391 sha: doc_id: 336837 cord_uid: rerp1g1w previously, we showed that 3% (31/1032)of asymptomatic healthcare workers (hcws) from a large teaching hospital in cambridge, uk, tested positive for sars-cov-2 in april 2020. about 15% (26/169) hcws with symptoms of coronavirus disease 2019 (covid-19) also tested positive for sars-cov-2 (rivett et al., 2020). here, we show that the proportion of both asymptomatic and symptomatic hcws testing positive for sars-cov-2 rapidly declined to near-zero between 25th april and 24th may 2020, corresponding to a decline in patient admissions with covid-19 during the ongoing uk ‘lockdown’. these data demonstrate how infection prevention and control measures including staff testing may help prevent hospitals from becoming independent ‘hubs’ of sars-cov-2 transmission, and illustrate how, with appropriate precautions, organizations in other sectors may be able to resume on-site work safely. the role of nosocomial transmission of sars-cov-2 has been highlighted by recent evidence suggesting that 20% of sars-cov-2 infections among patients in uk hospitals and up to 89% of infections among hcws may have originated in hospitals (evans et al., 2020; iacobucci, 2020) . since the introduction of 'lockdown' in the uk, community transmission rates of sars-cov-2 have generally declined (public health england (phe), 2020). conversely, concerns have been raised that hospitals could become independent 'hubs' for ongoing sars-cov-2 transmission between patients and hcws, which would effectively prolong the epidemic (iacobucci, 2020) . in this context, the evolution of the epidemic curves of a hospital's symptomatic and asymptomatic workforce has not been well described. we recently initiated a comprehensive hcw screening programme for sars-cov-2 in a large teaching hospital in cambridge, uk. over a 3-week period from 6th to 24th april 2020, 3% (31/ 1032) hcws in the asymptomatic screening arm, 15.4% (26/169) hcws in the symptomatic screening arm, and 7.7% (4/52) contacts in the symptomatic household contact screening arm tested positive for sars-cov-2 (rivett et al., 2020) . our data from the asymptomatic screening arm were consistent with the results of shields et al. (shields et al., 2020) . over the next 4 weeks from 25th april to 24th may 2020, we performed a further 3388 additional tests. here, we present these longitudinal data, in the context of the hospital patient population and wider local community. testing for sars-cov-2 rna was performed with real-time rt-pcr using throat and nose swab samples of hcws from cambridge university hospitals nhs foundation trust (cuhnft) and their symptomatic household contacts. over the new study period (25th april to 24th may 2020), 2611 additional tests were performed in the hcw asymptomatic screening arm, 555 additional tests in the hcw symptomatic screening arm, and 216 additional tests in the hcw household contact screening arm. a further six tests did not have a clearly recorded arm of origin. over the entire study period, the median age of hcws and their household contacts was 36.5 and 35.5 years, respectively. about 68.4% were female and 31.6% were male. of the individuals testing positive over the entire study period, the median age of hcws and their household contacts was 32 and 47 years, respectively. about 77.9% of all positive tests were from females and 22.1% from males. table 1 summarizes the total number of hcws testing positive through either arm of the screening programme, according to the job role. a comparison of the proportions of hospital employees from each job role that tested positive through the hcw symptomatic screening arm revealed no statistically significant difference (pearson's chi-square test p=0.419). reasonable comparison of the proportions testing positive through the hcw asymptomatic screening arm was not possible due to non-random sampling of different areas of the hospital, meaning some job roles had been more frequently targeted for asymptomatic screening than others. between 25th april and 24th may 2020, a total of 34 new positive tests were reported. in the hcw symptomatic and hcw symptomatic household contact screening arms combined (reflecting all individuals with self-reported symptoms at the time of testing), 13/771 (1.7%) tests were positive, which was significantly lower than 30/221 (13%) in the original study period (fisher's exact test p<0.0001). in the hcw asymptomatic screening arm, 21/2611 (0.8%) tests were positive, which again was significantly lower than 31/1032 (3%) in the original study period (fisher's exact test p<0.0001). as we previously observed (rivett et al., 2020) , individuals captured in the hcw asymptomatic screening arm were generally asymptomatic at the time of screening; however, these individuals could be divided into subgroups. in the first subgroup, 8/21 (38%) hcws had no symptoms at all. of these, 5/8 (63%) remained entirely asymptomatic 5-7 weeks after their positive test, whereas 2/8 (25%) developed symptoms 24-48 hr after testing. one hcw could not be contacted to obtain further history. in the second subgroup, 6/21 (29%) had retrospectively experienced some symptoms prior to screening. of these, 5/6 (83%) had symptoms with a high pre-test probability of covid-19 (rivett et al., 2020) commencing >7 days prior to screening, of whom 3/5 had appropriately self-isolated then returned to work, and 1/5 was tested shortly after developing symptoms. 1/6 (17%) had symptoms with a low pre-test probability of covid-19 (rivett et al., 2020) commencing <7 days prior to screening and had not self-isolated. in the third subgroup, 7/21 (33%) were detected through repeat sampling of hcw who previously tested positive. of these, 4/7 (57%) were tested to determine their suitability to return to work with severely immunocompromised/immunosuppressed patients, as dictated by uk national guidance (national institute for health and care excellence (nice), 2020). the remaining 3/7 (43%) were from hcws tested incidentally for the second time in the asymptomatic hcw screening programme. the median interval between serial positive tests was 16.5 days (iqr 9.5-19.5). all cases were attributable to prolonged sars-cov-2 rna detection from a single infection, rather than re-infection. our approach to patients with repeatedly positive sars-cov-2 pcr tests is described in the methods. the fraction of positive tests among the hcw asymptomatic, and hcw symptomatic and household contact screening groups combined varied over time ( figure 1a , table 2 ). in particular, during the last 2 weeks of the study period (11th to 24th may 2020), we identified only four positive sars-cov-2 samples from 2016 tests performed, two from the hcw asymptomatic and two from the hcw symptomatic/symptomatic household contact arms. this fall in positive hcw tests mirrored the decline in both patients testing positive at cuhnft and those tested throughout the wider region ( figure 1b) . similar trends were observed in a smaller cohort study of hcws in london (treibel et al., 2020) . in our original study between 6th and 24th april 2020, we described in detail two clusters of hcw infections (rivett et al., 2020) . from 25th april to 24th may 2020, we detected one additional cluster on a general medical ward with a separate area for patients with proven covid-19 and another area for those without. this was identified through targeted screening of the ward over a 24 hr period from 4th to 5th may 2020, in response to four staff testing positive through the hcw symptomatic arm of the screening programme from 27th to 30th april 2020. reactive screening of a table 1 . combined data for sars-cov-2 rna positive hcws by role and screening arm, from the present study and our previous study (rivett et al., 2020) . difference in proportions of hcws testing positive through the symptomatic screening arm was analysed using pearson's chi-square test. overall, 360 individuals underwent repeat testing, either as part of the asymptomatic screening programme, or for other reasons as previously described (rivett et al., 2020) . the median turnaround time from sample arrival in the laboratory to final verification was 18 hr 45 min. positive results were called out on the same day, with negative results emailed within 24 hr. further 40 staff from the same ward identified a further three positive asymptomatic hcws. in addition, a further two hcws tested positive in an asymptomatic screen of 30 individuals from a closely related clinical area (designated for non-covid patients) on 6th may 2020. our data demonstrate a dramatic fall in the prevalence of symptomatic and asymptomatic sars-cov-2 infection among hcws in our hospital during the study period. on average, the number of secondary infections among hcws arising from each infected hcw (effectively, the reproduction number (r) for sars-cov-2 transmission between hcws) must therefore be <1. as well as an acquisition from other hcws, infections among hcws may also be acquired from patients, as well as other individuals outside the hospital. our study period coincided with a decline in the rate of infection across our local community, and our data are consistent with a reduction in transmission within the hospital, a reduction in community-based acquisition of infection by hcws, or (most likely) a combination of both. in the absence of detailed epidemiological data, it is not possible to formally differentiate between these possibilities or determine their relative effect sizes. nonetheless, our identification of hcw infection clusters in specific areas of the hospital highlighted the potential for workplace acquisition of sars-cov-2, which may lead to self-sustaining outbreaks if left uninterrupted (rivett et al., 2020; meredeth et al., 2020) . for each of these clusters, timely identification of hcw infection proved effective in terminating chains of hospital transmission between staff, preventing ongoing nosocomial infection. with the incidence of infection having fallen significantly in hospitalised patients, hcws and the wider community, many hospitals across the uk and further afield have been afforded precious time to build the infrastructure necessary to establish comprehensive screening programmes in anticipation of a possible second epidemic peak. for hospitals already operating newly established screening programmes, the challenge now is to up-scale to the point that screening can occur at a frequency that permits pre-symptomatic capture of as close to 100% of all new infections as possible. this approach will enable staff to be removed from the workplace at the time of peak infectivity (he et al., 2020) . the minimum screening frequency required needs to be carefully modelled, with recent estimates suggesting the need for weekly testing to prevent 16-33% of onward transmission from hcws, depending on the time taken for results to be reported, and another study estimating the need for daily screening to prevent 65% of hcw-to-hcw transmission events (evans et al., 2020; grassly et al., 2020) . in practice, we have observed good results in our hospital with a current frequency of asymptomatic screening every 2-4 weeks. those being screened are prioritised by anticipated ward-based exposure to covid-19, with additional targeted screens triggered by excess staff sickness or the identification of symptomatic cases on specific wards (rivett et al., 2020) . in addition to asymptomatic screening, testing of symptomatic hcws is essential for preventing excessive erosion of the hospital workforce by self-isolation on the basis of symptoms alone, and testing of symptomatic hcw household contacts negates the need for unnecessary self-quarantine periods for co-habiting hcws. we found uptake to the hcw symptomatic household contact screening arm of our programme to be notably lower than the hcw symptomatic arm despite regular communications to advertise the service within cuhnft. this lack of uptake may reflect a lack of awareness that symptomatic non-hcws were eligible for testing, provided they shared a household with a hospital employee. many non-hospital employees may also have been more inclined to attend national testing centres or be less aware of the spectrum of covid-19 symptoms. importantly, our data demonstrate that cuhnft was not acting as an independent 'hub' for ongoing covid-19 transmission among hcws. the absence of nosocomial transmission likely reflects the combined efficacy of hcw testing, stringent prospective, and reactive infection prevention and control measures, and appropriate social distancing among the workforce. these findings should give reassurance to both hospital staff and patients that healthcare facilities remain safe places to give and receive care. furthermore, since cuhnft, with approximately 11,000 staff members (many of whom are based in the hospital) is a major regional employer, we predict that comparable organisations in other sectors may also be able to resume on-site work safely by instigating similar precautions. staff screening protocols we previously described protocols for staff screening, sample collection, laboratory processing, and results reporting in detail (rivett et al., 2020) . these methods remained unchanged throughout this study period. two parallel streams of entry into the testing programme included (i) hcw symptomatic, and hcw symptomatic household contact screening arms and (ii) an hcw asymptomatic screening arm. in the former, any patient-facing or non-patient-facing hcw could voluntarily refer themselves or a household contact, should they develop symptoms suggestive of covid-19. in the latter, hcws could volunteer to take part in a rolling programme of testing for all patient-facing and non-patient-facing staff working in defined clinical areas thought to be at risk of sars-cov-2 transmission. testing was performed (i) at temporary on-site 'pods'; (ii) via self-swabbing kits delivered to hcws in their area of work. all individuals in each arm of the programme performed a self-swab at the back of the throat then the nasal cavity, followed by rna extraction and amplification using realtime rt-pcr . cluster investigation was initiated when three or more hcws working in the same clinical area tested positive for sars-cov-2 in 1 week . current national institute for health and care excellence (nice) guidelines require a negative test before returning to work with immunocompromised patients (national institute for health and care excellence (nice), 2020). in accordance with the uk national guidance, individuals with repeat positive screens following a minimum period of 7 days self-isolation were advised to continue working if they were not scheduled to come into close contact with heavily immunocompromised patients, provided they remained asymptomatic (uk government, 2020) . this approach to managing repeat positive screens is further supported by recent data from the korea centers for disease control and prevention, which showed no clear evidence of onward transmission to the contacts of 285 repeat-positive individuals, 108 of whom had samples taken for attempted viral culture, which was universally unsuccessful (korea centers for disease control & prevention (kcdc), 2020). additional small studies have also demonstrated an inability to culture virus from clinical samples obtained later than 8 days after symptom onset, suggesting prolonged detection of viral rna is unlikely to indicate an ongoing risk of transmission (wö lfel et al., 2020; bullard et al., 2020) . swab result data for hcws and patients were extracted directly from the hospital-laboratory interface software, epic (verona, wi) and from sars-cov-2 point of care testing. data for sars-cov-2 infections from the local community were extracted from public health england's data dashboard (public health england (phe), 2020). data were collated using microsoft excel, and figures produced with graphpad prism (graphpad software, la jolla, ca). fisher's exact test was used to compare the proportion of hcws testing positive in this study period to that of our previous study period (rivett et al., 2020) . pearson's chi-square test was used for comparison of the proportions of hcws testing positive in each job role. conceptualization, data curation, formal analysis, investigation, methodology, writing -original draft, project administration, writing -review and editing william david có rdova jimé nez, fathima nisha begum samad, data curation, investigation, methodology, project administration, writing -review and editing data curation, investigation, methodology, writing -review and editing resources, data curation, methodology, project administration, writing -review and editing data curation, methodology, writingreview and editing data curation, software, formal analysis, writing -review and editing mark ferris, resources, investigation, methodology, project administration, writing -review and editing afzal chaudhry, resources, data curation, investigation, methodology, project administration, writing -review and editing conceptualization, resources, data curation, investigation, methodology, writing -review and editing resources, data curation, supervision, investigation, methodology, writing -review and editing conceptualization, data curation, investigation, methodology, project administration, writing -review and editing conceptualization, supervision, investigation, methodology, project administration, writing -review and editing data curation, formal analysis, investigation, methodology, project administration, writing -review and editing; stephen baker, conceptualization, data curation, formal analysis, supervision, funding acquisition, investigation, methodology, writing -original draft data curation, formal analysis, supervision, funding acquisition, investigation, visualization, methodology, writing -original draft, project administration, writing -review and editing author orcids sushmita sridhar ethics human subjects: as a study of healthcare-associated infections, this investigation is exempt from requiring ethical approval under section 251 of the nhs act 2006 (see also the nhs health research authority algorithm predicting infectious sars-cov-2 from diagnostic samples the impact of testing and infection prevention and control strategies on within-hospital transmission dynamics of covid-19 in hospitals role of testing in coivd-19 control london temporal dynamics in viral shedding and transmissibility of covid-19 covid-19: doctors sound alarm over hospital transmissions korea centers for disease control & prevention (kcdc). 2020. findings from investigation and analysis of repositive cases rapid implementation of real-time sars-cov-2 sequencing to investigate healthcare associated covid-19 infections national institute for health and care excellence (nice). 2020. covid-19 rapid guideline: haematopoietic stem cell transplantation public health england (phe). 2020. coronavirus (covid-19) in the uk screening of healthcare workers for sars-cov-2 highlights the role of asymptomatic carriage in covid-19 transmission sars-cov-2 seroconversion in health care workers a blueprint for the implementation of a validated approach for the detection of sars-cov2 in clinical samples in academic facilities covid-19: pcr screening of asymptomatic health-care workers at london hospital stay at home advice virological assessment of hospitalized patients with covid-2019 the funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication. all data generated or analysed during this study are included in the manuscript and supporting files. key: cord-335638-p84nmtfp authors: swaminathan, ashwin; martin, rhea; gamon, sandi; aboltins, craig; athan, eugene; braitberg, george; catton, michael g.; cooley, louise; dwyer, dominic e.; edmonds, deidre; eisen, damon p.; hosking, kelly; hughes, andrew j.; johnson, paul d.; maclean, andrew v; o’reilly, mary; peters, s. erica; stuart, rhonda l.; moran, rodney; grayson, m. lindsay title: personal protective equipment and antiviral drug use during hospitalization for suspected avian or pandemic influenza(1) date: 2007-10-17 journal: emerg infect dis doi: 10.3201/eid1310.070033 sha: doc_id: 335638 cord_uid: p84nmtfp for pandemic influenza planning, realistic estimates of personal protective equipment (ppe) and antiviral medication required for hospital healthcare workers (hcws) are vital. in this simulation study, a patient with suspected avian or pandemic influenza (api) sought treatment at 9 australian hospital emergency departments where patient–staff interactions during the first 6 hours of hospitalization were observed. based on world health organization definitions and guidelines, the mean number of “close contacts” of the api patient was 12.3 (range 6–17; 85% hcws); mean “exposures” were 19.3 (range 15–26). overall, 20–25 ppe sets were required per patient, with variable hcw compliance for wearing these items (93% n95 masks, 77% gowns, 83% gloves, and 73% eye protection). up to 41% of hcw close contacts would have qualified for postexposure antiviral prophylaxis. these data indicate that many current national stockpiles of ppe and antiviral medication are likely inadequate for a pandemic. of current stockpiles. this study aimed to estimate the resource needs that a hospital might face in the fi rst few hours of management of a single patient who sought treatment with possible avian or pandemic infl uenza (api) or similar highly virulent respiratory infection. in a prospective, multicenter, simulation exercise, we assessed the initial 6 hours of management of a patient (actor) who appeared for treatment at a hospital emergency department with a history consistent with api. tertiary-level university teaching hospitals across eastern australia were invited to participate. the inclusion criteria were willingness to join the simulation and possession of a formal local infection control protocol for the management of api that followed australian (3) or who guidelines (7) . the study was approved as a quality assurance project by the ethics committee at each participating site. for each of the participating hospitals, the 6-hour simulation was conducted midweek, beginning between 8:30 and 9:30 am, to avoid the busiest emergency department periods and to minimize the possibility that the care of actual patients might be compromised. the simulated patient was an actor unknown to the hospital staff, who appeared at the triage area of the emergency department and followed a prerehearsed script designed to trigger the hospital protocol for api. the standardized history included a 72-hour period of high fever, cough, shortness of breath, and severe malaise after a recent return from a southeast asian country. the patient reported handling unwell live poultry in a rural setting where human cases of avian infl uenza were known to have occurred. this standarized clinical scenario was chosen because guidelines for managing human cases of avian infl uenza (h5n1) form the current template for pandemic infl uenza case management (4, 5, 7) . to heighten staff awareness of the appropriate management of an api case, each hospital organized education sessions on ppe use, infection control practices, and protocol familiarization in the 1-2 weeks before the simulation. staff members were informed that the simulation would occur at some time during the allocated week (but not the exact day) and were instructed that hospital protocol should be followed as if it were an actual api case. each site had at least 3 trained infection control observers available who were familiar with using a modifi ed version of a validated hand hygiene assessment data input tool (8) to accurately record potential api exposures in a standard manner. the observers were provided by the coordinating center or by the participating hospital. a principal investigator (a.s.) was present at each simulation to ensure standardization. the following 3 procedures were observed and assessed (figure) : 1) patient management through triage, emergency, radiology, and inpatient ward (including transfer between areas); 2) respiratory specimen collection, transport, and processing; and 3) cleaning of clinical areas after the suspected api patient had left the area or the simulation had been completed. detailed observations were collated on infection control practice, clinical resources used, sequence of donning and removing ppe, time spent by the patient in each clinical area, and close contacts and exposures generated. the observation period could be stopped at any time if an actual patient's care was judged to be compromised by continuation of the simulation. at the time of collecting blood, respiratory specimens, or chest radiographs, surrogate specimens (venipuncture tube containing water, water-moistened swabs, and archival chest x-ray, respectively) were substituted by the accompanying study observer. surrogate blood and respiratory specimens were followed to the laboratory, where infection control practices were observed until specimens were sent to the reference laboratory for molecular testing. a hcw was defi ned as any person working within the healthcare facility. we used the who defi nition of a "close contact" as any person (including non-hcws) coming within 1 m of an api patient within or outside of an isolation room or area (7) . close contacts were counted only once. an "exposure" was counted each time a close contact came within 1 m of the api patient. a "ppe item" included a disposable gown, pair of gloves, pair of protective eyewear, or n95 mask (or equivalent particulate respirator). a "ppe set" was defi ned as the appropriate combination of ppe items recommended for hcw use in a particular clinical setting (7) ( table 1) . "opportunity for ppe item use" was defi ned as any instance of actual use of a ppe item during the study as well as any instance where the wearing of a ppe item was recommended by who guidelines (7) , as objectively noted by accompanying study observers (table 1 ). these items included ppe worn by hcws involved in direct patient care (hcw close contacts) and ancillary hcws who performed indirect clinical tasks associated with the api case-patient such as cleaning, ward support, and specimen transportation and processing. environmental decontamination of clinical areas after use was considered adequate if cleaning and disinfection procedures were undertaken in a manner consistent with who recommendations (7) . the time spent in each clinical area was recorded from when the api patient fi rst entered an area to the time when the patient entered the next area. for the purpose of identifying hcw close contacts who would be offered postexposure antiviral prophylaxis, hcw close contacts were stratifi ed into either moderate-or lowrisk groups derived from who criteria (9) . high-risk close contacts, defi ned as "household or close family contacts of a strongly suspected or confi rmed avian infl uenza (h5n1) patient" were not relevant to our study. the moderate-risk group included hcw close contacts wearing an insuffi cient or inappropriate ppe set during any of their exposures. the low-risk group included hcw close contacts wearing an appropriate ppe set for all exposures (9) . the study outcome measures were the following: 1) number of close contacts associated with the api patient during the initial 6 hours of patient management, including how many of these were hcw close contacts; 2) the total number of exposures experienced by close contacts; 3) overall quantity and type of ppe items (gowns, gloves, n95 masks, eyewear) actually used during the simulation by hcw close contacts and ancillary hcws; 4) overall "opportunities for ppe item use" for hcw close contacts and ancillary hcws (i.e., actual use plus missed opportunities for appropriate ppe use); and 5) stratifi cation of hcw close contacts into medium-or low-risk groups for the purpose of recommending antiviral postexposure prophylaxis. nine tertiary-level university teaching hospitals in 3 states of eastern australia participated in the study ( table 2 ). the simulations occurred in the winter season, from may through august 2006. all sites conducted targeted staff education sessions 1-2 weeks before their exercise. seven of the 9 simulations proceeded for the planned 6 hours of observation, and 2 were curtailed because of a critical need for the emergency department bed. had these latter 2 sites continued, the patient would almost certainly have spent the entire study period isolated in the emergency department, as suitable ward beds were not available. the time spent in each clinical area for each site is summarized in table 2 . all sites performed radiography within the emergency department. the number of close contacts and total exposures to the potential api patient are summarized in table 3 . the highest number occurred in the fi rst hour of hospital care (triage and emergency department), which correlated with the initial intensive clinical and radiologic assessment and gloves, either gown or apron patient transport within healthcare facilities gown, gloves specimen transport and processing not defined except to use "safe handling practices"; interpreted as use of gloves (minimum) and gown if opening specimen bag. *who, world health organization; hcw, healthcare worker; ppe, personal protective equipment; api, avian or pandemic influenza. †derived from (7). [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] . hcw close contacts constituted 85% of all close contacts; the remainder were patients or visitors who were generally exposed in the triage area. all 9 sites processed the respiratory specimen, with an average of 2.9 hcws (median 3, range 2-6) handling or transporting the specimen, predominantly in the pathology department. two sites used a vacuum transport system to deliver specimens from the emergency department to the laboratory, contrary to who recommendations (7) . environmental decontamination of clinical areas after departure of the suspected api patient was performed haphazardly at all sites. the triage area was appropriately cleaned in none of the 9 sites, whereas the emergency department and ward areas at sites that completed the full simulation were cleaned appropriately in 6 of 7, and 4 of 7 instances, respectively; 1-2 cleaners were required per clinical area to appropriately perform this task. large quantities of n95 masks, disposable gowns, gloves, and eye protection were used and indicated during the study period (table 4 ). adherence to appropriate use by hcws (hcw close contacts and ancillary hcws) was variable and depended on the particular ppe item, clinical area, and participating institution. appropriate use of n95 masks by hcws occurred in 93% of exposures (actual use/ total opportunities for ppe use, 18/19.4), although the corresponding fi gures for disposable gowns, gloves, and eye protection were lower (77%, 83%, and 73%, respectively). hcw close contacts were stratifi ed into either moderate-or low-risk groups, depending on whether an appropriate ppe set was worn during every exposure. the proportions of hcw close contacts who appropriately wore a ppe set, rather than an n95 mask alone, for every exposure were 59% and 92%, respectively. thus, depending on how rigorously who antiviral medication guidelines (9) were followed, from 8% to 41% of all hcw close contacts would be classifi ed as having experienced a medium-risk exposure and therefore would potentially require postexposure antiviral prophylaxis. this amounts to an average of 0.8 to 4.3 courses of antiviral medication per suspected api patient during the initial 6 hours of management. to our knowledge, this is the fi rst multicenter study to estimate the quantity of ppe and antiviral therapy that may be required to manage patients with suspected api admitted to hospitals. during the initial 6 hours of hospital assessment, the number of close contacts of a single suspected api patient was high (mean 12.3), with a mean number of exposures of 19.3. not surprisingly, most (85%) close contacts were hcws, and ppe use was at its most intense (11) 3 (9) 7 (10) 6 (9) 7 (10) 6 (9) 3 (4) † 3 (5) † 5.9 (9.9) ‡ ward 4 (7) 4 (5) 2 (5) 2 (8) 3 (3) 4 (9) 2 (5) --3.0 (6.0) by study period, h 0-1 10 (12) 8 (8) 3 (4) 6 (8) 7 (7) 8 (8) 5 (5) 9 (10) 5 (6) 6.8 (7.6) (9) . if appropriate ppe, especially n95 masks, were not available, the number of hcws who would experience moderate-risk api exposure requiring postexposure antiviral prophylaxis would increase substantially. notably, a substantial minority of close contacts (15%; ≈2 per api patient) were non-hcws (e.g., hospital patients or visitors), generated primarily in the triage area. although the duration of unprotected exposure was often short (<5 minutes) for these persons, they represent a potential risk for subsequent community and hospital spread of api. this highlights the importance, in triage and reception areas particularly, of using appropriate infection control measures and signage to assist in cohorting of potential api patients and minimizing exposure of unprotected bystanders. the critical importance of effective ppe in hospital infection control was demonstrated during the outbreak of sars in 2003 (10) (11) (12) (13) (14) . nosocomial transmission of sars was a prominent feature of the epidemic (15) and played a large role in the initiation and maintenance of outbreaks. as reported in a case-control study by seto et al. (13) , staff who used masks (in particular), gowns, and performed hand hygiene were less likely to become sars infected than those who did not. similarly, lau et al. (14) noted that inconsistent use of ppe by hcws working on wards with sars patients in hong kong was associated with a signifi cantly higher risk for nosocomial disease transmission. provision of adequate ppe stock is therefore likely to be important in controlling the spread of api. many countries are compiling extensive stockpiles of ppe and antiviral medications for use if a new pandemic occurs. planning for suffi cient numbers of resource items is complex and dependent on estimations of pandemicrelated additional emergency presentations, hospitalizations, general practice, and outpatient visits. in australia, offi cial estimates of additional hospitalizations range from 57,900 to 148,000 (4). our data suggest that management of this number of hospitalizations without regard for suspected infl uenza patients who are assessed but who are not suffi ciently ill to require admission, would require from 1,123,260 to 3,714,800 ppe sets (depending on whether they were n95 masks, gowns, or gloves, or all 3 items). although ascertaining (from these data) the number of courses of postexposure antiviral prophylaxis required is diffi cult, if stocks of readily available ppe were inadequate, the number of courses of antiviral medication required would likely increase dramatically, up to 12-13 courses per suspected api case during the initial 6-hour assessment. thus, adequate stocks of ppe provide a means of protecting valuable antiviral drug stockpiles for use in ill or heavily exposed persons. an important consideration when extrapolating our data to other healthcare systems is that recommendations regarding the optimal form of respiratory protection vary between countries. the who interim guidelines for management of human cases of avian infl uenza (ai) state, "hcws working with ai-infected patients should select the highest level of respiratory protection available, preferably a particulate respirator… designed to protect the wearer from respiratory aerosols expelled by others" (7) . this recommendation is refl ected in the australian pandemic infl uenza guidelines (3) and explains the high use of n95 masks in our study. however, pandemic infl uenza plans in the united kingdom (5), united states (6), and canada (16) currently recommend the use of surgical masks for close patient care, unless the hcw is engaged in procedures in which aerosolization occurs. thus the proportion of n95 masks to surgical masks required will vary between countries with different guidelines, which affects assessment of stockpile adequacy. our study did not assess the relative effi cacy of n95 masks compared with surgical masks for protection against api transmission. this study has several limitations. first, the duration of the study was short (6 hours), much shorter than the likely in-hospital stay of days for a patient with severe infl uenza. thus, total ppe and antiviral agent usage per admission is likely to be substantially higher. second, the study was conducted at a less busy time of day for emergency departments and therefore may not refl ect the greater number of persons who would likely be exposed in the triage and emergency department areas during busier periods. third, the patient was not clinically unwell or hypoxic; thus, relatively few hcws were required to assess, manage, or review the api patient's condition. fourth, we observed the management of the index api case-patient alone, although we acknowledge that actual patients are likely to come to the hospital with other household members (high-risk close contacts). however, extending observation to include management of asymptomatic but potentially infectious accompanying persons in a standardized manner would have substantially increased the complexity of the exercise. our fi ndings, therefore, likely underestimate the true resources required and contacts exposed for the management of a genuine api patient. finally, the presence of observers and the preceding education sessions may have artifi cially increased compliance with ppe use, although in the event of a true pandemic one might assume that hcw compliance rates would be high as they aim to minimize their personal risk. also, this study was designed to quantify the use of ppe in an environment with raised awareness of infection control practice, mimicking that which might occur during a pandemic, and thus provide relevant data for health resource planners. this study suggests that managing a single api patient is resource intensive and exposes a high number of persons to a potentially severe infection. these data represent the likely minimum clinical resources required during an api patient's initial hospital assessment using current whoderived infection control guidelines. given our fi ndings, if a global infl uenza pandemic occurs with attack rates even on the lower end of projected estimates, demand for ppe and antiviral medication in healthcare facilities will likely outstrip current supply in industrialized countries, let alone the supply in resource-poor settings. further studies are needed to assess resource usage in other healthcare settings such as intensive care units, fever clinics, general practice, and the community. the economic impact of pandemic infl uenza in the united states: priorities for intervention world health organization writing group. nonpharmaceutical interventions for pandemic infl uenza, national and community measures national infl uenza pandemic action committee. interim infection control guidelines for pandemic infl uenza in healthcare and community settings. annex to australian health management plan for pandemic infl uenza department of health and ageing. australian health management plan for pandemic infl uenza guidance for pandemic infl uenza: infection control in hospitals and primary care settings united states department of health and human services. hhs pandemic infl uenza plan supplement 4, infection control avian infl uenza, including infl uenza a (h5n1) in humans: who interim infection control guidelines for health care facilities hand hygiene: a standardized tool for assessing compliance who rapid advice guidelines on pharmacological management of humans infected with avian infl uenza a (h5n1) virus the severe acute respiratory syndrome severe acute respiratory syndrome (sars) and healthcare workers sars outbreak: global challenges and innovative infection control measures effectiveness of precautions against droplets and contact in prevention of nosocomial transmission of severe acute respiratory syndrome (sars) sars transmission among hospital workers in hong kong public health agency of canada. infection control and occupational health guidelines during pandemic infl uenza in traditional and nontraditional health care settings (annex f) email: lindsay.grayson@austin.org.au emerging infectious diseases • www.cdc.gov/eid • we thank the infection control, emergency, pathology, and radiology departments, ward staff and "patient" volunteers of the following hospitals for their kind assistance in this study: austin health, box hill hospital, barwon health, monash medical centre, royal melbourne hospital, st. vincent's hospital, western hospital, royal hobart hospital, and westmead hospital.the study was funded in part by a grant from the department of human services, victoria, australia, which played no role in the data analysis of this study.dr swaminathan is infectious diseases registrar at austin health, melbourne, australia. among his main clinical interests are tropical infectious diseases and public health policy development. all material published in emerging infectious diseases is in the public domain and may be used and reprinted without special permission; proper citation, however, is required. key: cord-311151-mrsjhjh4 authors: zhang, yuemei; cheng, sheng-ru title: estimating preventable covid19 infections related to elective outpatient surgery in washington state: a quantitative model date: 2020-03-20 journal: nan doi: 10.1101/2020.03.18.20037952 sha: doc_id: 311151 cord_uid: mrsjhjh4 background: as the number of suspected and confirmed covid19 cases in the us continues to rise, the us surgeon general, centers for disease control and prevention, and several specialty societies have issued recommendations to consider canceling elective surgeries. however, these recommendations have also faced controversy and opposition. objective: the goal of this study is to provide a quantitative analysis and model for preventable covid19 infections from elective outpatient or ambulatory surgery cases, which can also be adapted to analyze covid19 transmission in other healthcare settings. furthermore, given the controversy over the appropriate handling of elective surgical cases during this pandemic, we hope that our results may have a positive impact on health policy and public health. methods: using previously published information on elective ambulatory or outpatient surgical procedures and publicly available data on covid19 infections in the us and on the diamond princess cruise ship, we calculated a transmission rate and generated a mathematical model to predict a lower bound for the number of healthcare-acquired covid19 infections that could be prevented by canceling or postponing elective outpatient surgeries in washington state. results: our model predicts that over the course of 30 days, at least 2445 preventable patient infections and at least 1557 preventable healthcare worker (hcw) infections would occur in wa state alone if elective outpatient procedures were to continue as usual. the majority of these infections are caused by transmission from hcw who became infected at work. conclusion: given the large numbers of covid19 infections that could be prevented by canceling elective outpatient surgeries, our findings support the recommendations of the us surgeon general, cdc, american college of surgeons (acs), american society of anesthesiologists (asa), and anesthesia patient safety foundation (apsf) to consider rescheduling or postponing elective surgeries until the covid19 pandemic is under better control in the us. despite its humble origins as a cluster of cases restricted to wuhan, china in nov. and dec. of 2019, covid-19 spread explosively across the globe and was officially declared a pandemic by the who on march 11, 2020. 1 in the united states, the number of confirmed cases has spiked from just 1 case between jan. 20, 2020 to 4661 confirmed positives and 85 deaths as of march 16, 2020. 2 washington state, the epicenter of the us outbreak and the location of the first american case, has had 904 covid19+ patients as of march 16, 2020. 3 given its rapid spread and 3.4% mortality rate, 4 countries like italy and china have been forced to ration limited healthcare resources, and there are concerns that the us may need to do so as well. 5 person-to-person transmission by asymptomatic individuals and pre-symptomatic individuals during the up-to-14 day incubation period 6 may play a significant role in this pandemic. [7] [8] [9] [10] infection transmission between covid19 patients and healthcare workers has also been documented. 11 given the current status of the covid19 outbreak, the us surgeon general, 12 centers for disease control and prevention (cdc), 13 american college of surgeons (acs), 14 american society of anesthesiologists (asa), and anesthesia patient safety foundation (apsf) 15 have recommended considering rescheduling or postponing some elective surgeries with the goal of conserving limited resources, such as ventilators and icu beds, and mitigating the risk of "exposing other inpatients, outpatients, and health care providers to the risk of contracting covid-19" from asymptomatic but infectious patients. 14 however, the american hospital association, the federation of american hospitals, the association of american medical colleges, and the children's hospital association have written a joint letter opposing the surgeon general's advice. 12 going along with the surgeon general's and acs's recommendations, multiple hospitals, including several major hospital systems in wa, are canceling or postponing elective surgery procedures. 16 17 the goal of this study is to provide a quantitative analysis and model for preventable covid19 infections from elective outpatient or ambulatory surgery cases. our model can also be adapted to analyze covid19 transmission in other healthcare settings. furthermore, given the controversy over the appropriate handling of elective surgical cases during this pandemic, we hope that our results may have a positive impact on health policy and public health. given much of the uncertainty regarding the pathophysiology and epidemiology of covid19, and the potential policy implications of our results, we chose to focus on lower bounds for preventable infections instead of upper bounds. . cc-by-nc-nd 4.0 international license it is made available under a is the author/funder, who has granted medrxiv a license to display the preprint in perpetuity. (which was not certified by peer review) the copyright holder for this preprint this version posted march 20, 2020. . https://doi.org/10.1101/2020.03. 18.20037952 doi: medrxiv preprint we are excluding symptomatic covid19+ patients from our model because their elective surgeries would likely be postponed or canceled due to the significantly increased risk of postoperative pulmonary complications if a surgical patient had a recent acute respiratory infection. 18 thus, our elective surgery patient population only includes uninfected individuals and asymptomatic or pre-symptomatic individuals (whose covid19 status would not be discovered given current testing limitations). since covid19 would not be suspected in these patients, healthcare workers interacting with them typically would not use the level of personal protective equipment (ppe) or precautions necessary to prevent covid19 transmission, especially if there were also restrictions due to ppe shortages within the clinical institution. the elective surgery population is estimated using data from the national health statistics reports on ambulatory surgery data in 2010. according to the report, an estimated 48 million elective ambulatory surgeries occur annually in the us. 19 since every center or healthcare institution has different holiday schedules and policies, we divided this number by 365 days/year for a lower bound of 131,506.85 cases per day nationally. to simplify the calculation for the estimated number of elective outpatient cases in wa, we assumed that the case number was directly proportional to population. we divided 131,506.85 daily cases by the us population estimate of 328 million, 20 then multiplied the quotient by wa's population of 7.6 million, 21 to arrive at approximately 3047 elective outpatient surgeries per day in washington state. in order to predict the lower bounds for the number of preventable patient and healthcare worker infections, we decided to minimize the number of unique healthcare workers (hcw) that patients would interact with in an elective outpatient setting. at minimum, each patient must interact with 4.5 hcw: one anesthesiologist, one surgeon or proceduralist, one circulator, one scrub technician, and 0.5 pre-operative / post-anesthesia care unit (pacu) nurses for both pre-op and post-op care, since the pacu nursing ratio is usually 1 nurse to 2 patients and the same nurse can care for a patient during pre-op and post-op. note that the actual number of hcw that patients will interact with can often be higher. the number of patients that each set of perioperative staff works with varies depending on the length of surgery and scheduling preferences. based on the clinical experiences of one of our authors, we will use the assumption that each hcw is responsible for an average of 5 cases or 5 unique patients. thus, we came up with the ratio of 4.5 hcw / 5 patients, or . cc-by-nc-nd 4.0 international license it is made available under a is the author/funder, who has granted medrxiv a license to display the preprint in perpetuity. the copyright holder for this preprint this version posted march 20, 2020. due to the 14-day incubation period of the virus, 6 coupled with the current resource limitations in the us, covid19 infections will not be detected until symptoms become evident. to estimate the asymptomatic infected population, we looked at publicly available data with at least 15 days of significant increase in confirmed covid19 case numbers and back-calculated the population count that would have likely been in the pre-symptomatic incubation phase on previous dates. this means that, for any time t, the number of asymptomatic but infected individuals can be estimated using the sum of new infections that were confirmed on t + 1 to t + 14 as follows: in other words, if someone is symptomatic and confirmed to be covid19+ on any of the days between t+1 to t+14, then s/he was infected but asymptomatic on day t. using publicly available data for the state of washington for dates feb. 28-march 16, 2020, our math shows that on feb. 28, 2020, there were at least 567 asymptomatic infected cases, despite there being only 1 officially confirmed case reported for that day. 3 similarly, on feb. 29, there would have been 636 asymptomatic infected individuals, 755 asymptomatic infected individuals on march 1, and 886 . cc-by-nc-nd 4.0 international license it is made available under a is the author/funder, who has granted medrxiv a license to display the preprint in perpetuity. the copyright holder for this preprint this version posted march 20, 2020. . https://doi.org/10.1101/2020.03. 18.20037952 doi: medrxiv preprint asymptomatic infected cases on march 2. we do not have any us data on asymptomatic individuals who ultimately never develop symptoms, so we will not include them. since our goal is to focus on minima, we used the number 567 as that was the lowest one in the group. news reports that the virus is thought to have been circulating within communities for weeks prior to the outbreak also support the idea that this number underestimates the actual prevalence of asymptomatic cases. 22 next, we needed to determine the ratio of asymptomatic uninfected people to uninfected people in the general population. we subtracted the confirmed infections on feb. 28, 2020 and the asymptomatic infected population on that day from the total population of wa in order to determine the uninfected population. we assume that since the majority of patients and hcws reside in wa, their infection statuses would initially also be representative of that of the general wa population. thus we multiplied our ratio with 3037 total patients and 2773 total hcw to arrive at the initial values of to investigate the number of preventable infections of healthcare workers from asymptomatic infected patients, we used a simple logistic model of transmission: in this equation, k is the transmission constant, i'(t) is the rate of change of infected population, and i(t) represents total infected population, including the asymptomatic infected population. since i'(t) is the rate of change of infected population, it can be observed that the number of total infected population of a discrete time t + 1 is calculated as i(t + 1) = i(t) + i'(t) . cc-by-nc-nd 4.0 international license it is made available under a is the author/funder, who has granted medrxiv a license to display the preprint in perpetuity. since we are interested in the total infection spread, data for some known infected population, both symptomatic and asymptomatic, is required. for this, we used data extracted from the diamond princess cruise ship. 23 new hcw-to-patient infections, then i(t) would represent asymptomatically infected hcw, and m(t) would represent uninfected patients showing up for surgery. these calculations would be repeated for every day in our model. since hcw and their patients interact much more closely with one another than they would with members of the general population outside this relationship, and we assume patients and hcw are following infection prevention guidelines such as social distancing appropriately, 24 we will assume the likelihood of either a patient or a hcw becoming infected with covid19 from outside the clinical setting is negligible compared to their likelihood of infection from another hcw or patient. by definition, outpatient surgery means that patients leave the institution each day and a new batch of patients with characteristics representative of the general population would arrive . cc-by-nc-nd 4.0 international license it is made available under a is the author/funder, who has granted medrxiv a license to display the preprint in perpetuity. the copyright holder for this preprint this version posted march 20, 2020. . https://doi.org/10.1101/2020.03. 18.20037952 doi: medrxiv preprint each day. although in real life, complications can occur that necessitate inpatient stays following outpatient surgery, for simplicity, we did not include that possibility in our model. therefore, the starting numbers of uninfected patients and asymptomatic infected patients that we used for our calculations stayed constant. on the other hand, since hcw were unlikely to have significant changes in their employment in the time period we were modeling, we designed a markov chain to track their infection timelines. new hcw infections comprised the d1 group for the following day, and hcw in d1 would get changed to d2 the following day, hcw in d2 would get changed to d3 the following day, so on and so forth. our model predicts that over the course of 30 days, at least 2445 preventable patient infections would occur in wa state alone if elective outpatient procedures were to continue as usual. of those infections, 2 can be attributed to patient-to-patient transmission and 2443 can be attributed to hcw-to-patient transmission. . cc-by-nc-nd 4.0 international license it is made available under a is the author/funder, who has granted medrxiv a license to display the preprint in perpetuity. the copyright holder for this preprint this version posted march 20, 2020. . preventable patient infections (yellow line) appears to behave in an exponential manner, while preventable hcw infections (green line) behaves logistically. a significant number of hcw and patient infections could be prevented if outpatient surgical procedures were canceled or postponed. the dotted lines represent mathematical projections based on our model, but in practice, since these occur after the perioperative workforce begins shrinking significantly, surgical case number will decrease and infection rate will slow down. based on our model, over the course of 30 days, at least 1557 preventable hcw infections would occur in wa state alone if elective outpatient procedures were to continue as usual. of those infections, 2 can be attributed to patient-to-hcw transmission and 1555 can be attributed to hcwto-hcw transmission. . cc-by-nc-nd 4.0 international license it is made available under a is the author/funder, who has granted medrxiv a license to display the preprint in perpetuity. the copyright holder for this preprint this version posted march 20, 2020. . in the absence of disease symptoms, infected hcw who are pre-symptomatic or asymptomatic would not be suspected of being covid19+, and therefore would continue to be a part of the active healthcare workforce. despite rising levels of infection, the size of the active healthcare workforce in the outpatient surgical setting stays fairly constant for the majority of our model's timeline. on day 30, there are still 2660 active hcw, which is about 96% of the original workforce. however, by day 39, the active perioperative workforce has dropped to 1985 hcw in washington state, which is an approximately 28% drop compared to the starting value. this means staffing shortages may transition from mild to severe within a short period of time. . cc-by-nc-nd 4.0 international license it is made available under a is the author/funder, who has granted medrxiv a license to display the preprint in perpetuity. the copyright holder for this preprint this version posted march 20, 2020 this model demonstrates that a substantial number of potential covid19 infections in both patients and hcw can be prevented by cancelling elective outpatient surgeries during this pandemic. in combination with the concern that we may not have enough healthcare resources for patients who are being admitted for covid19 symptoms, it appears that postponing elective surgeries may be an appropriate consideration. given the fact that there is still a lot of uncertainty and unavailable data regarding covid19, some of the numbers and assumptions in this model may be incorrect, which could affect the model's predictions. at first glance, the predicted numbers of preventable infections seem surprisingly high compared to the confirmed number of 769 positive covid19 cases in wa 3 and 4661 confirmed positive cases in the entire us. however, the growth rate of covid19 in the us has been rapid, increasing from 69 cases on 2/29/20 to 4661 confirmed cases just 17 days later. 2 due to the current state of covid19 testing, us statistics on confirmed covid19 cases may not be the most reliable, either. per cdc guidelines that were last updated 3/9/2020, laboratory testing for covid19 is only indicated for individuals who both develop respiratory symptoms consistent with covid19 and meet additional criteria, such as being hospitalized, having certain comorbidities, and/or having contact with suspected covid19+ individuals. 25 however, many covid19+ individuals may be asymptomatic or only have mild symptoms. 26 in addition, covid19 testing shortages may make the us statistics on covid19 cases less reliable. 27 according to dr. marty makary of johns hopkins, us statistics may be underestimating the number of cases of covid19, and he believes that as of march 13, 2020, there could be between 50,000 to 500,000 actual cases of covid19 in the us. 27 it is possible that many of our predicted new infections would not qualify for lab testing per the cdc's guidelines or would not be able to access it, and therefore would not be included in covid19 case counts. of note, the majority of new infections are transmitted by asymptomatic infected hcw, not by patients. by exclusively examining outpatient surgeries, we have a revolving door of patients, whereas the hcw stay at the surgical center or hospital for much longer periods of time, and the proportion of asymptomatic infected hcw that patients interact with accumulates. while we did not look at other healthcare settings, this seems to suggest that minimizing the risk of covid19 infection to hcw in general may be important to preventing hospital-acquired covid19 infections in patients as well. . cc-by-nc-nd 4.0 international license it is made available under a is the author/funder, who has granted medrxiv a license to display the preprint in perpetuity. (which was not certified by peer review) the copyright holder for this preprint this version posted march 20, 2020. . https://doi.org/10.1101/2020.03. 18.20037952 doi: medrxiv preprint given the high infection rates among hcw after a relatively short period of time, there is a risk that the healthcare system would collapse once enough hcw show symptoms in a similar timeframe and are unable to work. additionally, based on our analysis of the active perioperative workforce size, it seems that staffing would decrease gradually until a certain point at which the shortage worsens acutely and severely. although this would not be an issue for patient care if it only affected elective outpatient surgeries, since those could be rescheduled, many perioperative hcw work in hospitals or institutions that perform both elective and and non-elective (ie: urgent or emergent) cases. in those cases, any staffing shortages could cause significant patient harm if it affects the timeliness of urgent and emergent surgeries. ultimately, our findings support the recommendations of the us surgeon general, cdc, acs, asa, and apsf to consider rescheduling or postponing elective surgeries until the covid19 pandemic is under better control in the us. . cc-by-nc-nd 4.0 international license it is made available under a is the author/funder, who has granted medrxiv a license to display the preprint in perpetuity. (which was not certified by peer review) the copyright holder for this preprint this version posted march 20, 2020. . who director-general's opening remarks at the media briefing on covid-19 -11 an interactive web-based dashboard to track covid-19 in real time novel coronavirus outbreak (covid-19) who director-general's opening remarks at the media briefing on covid-19 -3 spiking u.s. coronavirus cases could force rationing decisions similar to those made in italy, china. the washington post european centre for disease prevention and control. novel coronavirus disease 2019 (covid-19) pandemic: increased transmission in the eu/eea and the uk -sixth update -12 substantial undocumented infection facilitates the rapid dissemination of novel coronavirus (sars-cov2) transmission interval estimates suggest pre-symptomatic spread of covid-19. medrxiv estimating the generation interval for covid-19 based on symptom onset data. medrxiv the contribution of pre-symptomatic transmission to the covid-19 outbreak. 2020, centre for mathematical modeling of infectious diseases over 1,700 frontline medics infected with coronavirus in china, presenting new crisis for the government surgeon general urges providers to 'consider stopping elective surgeries.' hospitals push back interim guidance for healthcare facilities: preparing for community transmission of covid-19 in the united states recommendations for management of elective surgical procedures. 2020, american college of surgeons asa-apsf joint statement on non-urgent care during the covid-19 outbreak anna wilde hospitals push off surgeries to make room for coronavirus patients seattle-area hospitals cancel elective procedures in response to coronavirus outbreak prediction of postoperative pulmonary complications in a populationbased surgical cohort ambulatory surgery data from hospitals and ambulatory surgery centers: united states united states census bureau. quick facts-united states united states census bureau. quickfacts-washington; united states how did it start? questions answered on the u.s. coronavirus outbreak. new york times novel coronavirus covid-19 (2019-ncov) data repository by johns hopkins csse why outbreaks like coronavirus spread exponentially, and how to "flatten the curve". the washington post, 2020. 25. centers for disease control and prevention. evaluating and testing persons for coronavirus disease 2019 (covid-19) south korea has tested 140,000 people for the coronavirus. that could explain why its death rate is just 0.6% -far lower than in china or the us don't believe the numbers you see': johns hopkins professor says up to 500,000 americans have coronavirus. yahoo! finance key: cord-322451-cwpz4akv authors: hsin, dena hsin-chen; macer, darryl r.j. title: heroes of sars: professional roles and ethics of health care workers date: 2004-07-27 journal: j infect doi: 10.1016/j.jinf.2004.06.005 sha: doc_id: 322451 cord_uid: cwpz4akv objectives. to examine the professional moral duty of health care workers (hcws) in the outbreak of severe acute respiratory syndrome (sars) in 2003. methods. descriptive discussion of media reports, analysis of ethical principles and political decisions discussed in the outbreak, with particular emphasis on the events in mainland china and taiwan. results. there were differences in the way that taiwan and mainland china responded to the sars epidemic, however, both employed techniques of hospital quarantine. after early policy mistakes in both countries hcws were called heroes. the label ‘hero’ may not be appropriate for the average hcw when faced with the sars epidemic, although a number of self-less acts can be found. the label was also politically convenient. conclusions. a middle ground for reasonable expectations from hcw when treating diseases that have serious risk of infection should be expected. while all should act according to the ethic of beneficence not all persons should be expected to be martyrs for society. it was too heavy to be called as a hero; i just do what i should do. -doctor facing sars in taiwan, may 2003. severe acute respiratory syndrome (sars) will go into the medical records as the first new panic disease that has swept international society in the 21st century. although the number of persons who died from the disease is currently less than a thousand, 1 it affected the lives of millions of persons in 2003. we want to discuss the important lessons that it raises for medical professionals-the 'heroes' of sars. the focus on sars was so high in the media that news of sars overshadowed the outbreak of another panic disease, ebola virus, that killed more than 100 persons in march 2003 in congo. the attention paid on sars meant less attention was given to disease outbreaks like ebola. 2 sars is the latest of more than 35 new or reemerged infectious diseases over the last 30 years. the difference was that most people in the world, especially in safe and secure social settings felt protected from ebola virus of africa, and even the global pandemic of hiv seems distant from most people who donned masks to avoid sars. sars infected and killed young and old, healthy and unhealthy, making everyone seem vulnerable. in taiwan, the sars outbreak started from the time a hospital was detected to have a widespread hospital infection. the hospital was sealed as an emergency and patients and staffs were all locked up inside the hospital building to isolate them from outside, to spread the disease. the quarantine order was announced without any warning and preparation, which caused a massive panic. 3 similar quarantine emergencies were reported in other places also. 4 hcws who were placed in working quarantine experienced fear, depression, anxiety, anger and frustration. there will be long-term psychological consequences for some of these persons. this paper discusses some of the ethical lessons of the first sars outbreak in early 2003, with a hope that lessons will be learnt in time for the next outbreak of sars, or similar new diseases that face those working in the field of infectious diseases control. during the international battle against sars one of the features was the proportion of frontline health care workers (hcw) who were infected and who died. according to the data compiled from the who until the 7 august 2003, 1 20% of all persons affected with sars were hcws (1725/8422). the percentage of hcw was highest in canada (43% with 3/41 deaths), and singapore (41%), higher than that reported for mainland china (19%), hong kong (22%) and taiwan (13% with 6/180 deaths). in the early stages of the outbreak, they had all unknowingly treated patients with sars. even for the latter stages in the outbreak in the first half of 2003, there were several hcw who became ill with sars in spite of 'full' precautions. when nurses and doctors see their colleagues being critically ill around them, dying or on ventilators, when just few days ago they seemed so robust and well, they realized the dangers of being a professional. despite the rapid advancement of knowledge with the intense research, and papers appearing in all major medical journals, 5 the threat of the disease to hcw will remain for some time. before a vaccine is made, there will always be a threat of being infected and killed on duty as a hcw. we witnessed a number of hcw who started to think about withdrawing from their post. it is ethically unacceptable to abandon patients. however, beyond the duty of a hcw, should we demand (or even expect) that hcw should be ready to sacrifice their lives for our society in severe pandemics, like the outbreak of sars. as one doctor in taiwan said: 'it too heavy to be called as a hero; i just did what i should'. we understand that even a virtuous doctor or nurse might not be willing to die for a patient. does the accepted norm of responsibility mean they must put their own lives at risk? one important point is that the social function of medical professionals can not be replaced by others. even in times of peace, we should always remember the reality that being a helper of sickness will always present a certain risk of being infected. medical professions have been well-rewarded by the society not only because they are competent in operating medicine but they chose the work of being a 'life saver'. in a number of countries in order to encourage hcw, the government and the public started to give the title of 'hero' to nurses and doctors who are working in the frontline of sars outbreak. on the other hand, some suggested to punish those who were afraid of treating sars patients. in taiwan this included threats of retracting their professional license. there are memories of the aids scars in the 1980s when some hospitals in asia refused to admit patients with hiv. in a 1992 survey by the japan hospital association it was found that 40% of hospitals refused hiv positive patients. 6 currently refusals are not permitted. can someone who makes an involuntary sacrifice be called as a hero? most nurses and doctors actually died from taking care of sars patients involuntarily. except for those on international teams who actively sought out sars patients, most did not choose to do so. in large scale hospital quarantines in beijing and taiwan the hospitals were encircled and no one could leave. many hcw in taiwan thus denied the title of hero. some said the more people call them in this way, the more they fear they are in danger. we could even imagine that the spiritual inspiration of being a 'hero' even lessens the implementation of good clinical precautions. in taiwan four nurses and two doctors sacrificed their life in taking care of sars patients. the numbers for other countries are not clear, but one can expect it to be higher for hong kong and mainland china, based on the proportion of infected hcws quoted above. in taiwan, a doctor died from giving airway intubations to a terminal old woman even with the protection of masks and glove; he was so young to graduate from medical school a few months ago and got married only 4 months before. a nurse died with her 7 month old fetus just because of a short contact with an undiagnosed sars patient in the emergency room. as those scary stories are repeated numerous times among hcws, can medical ethics overcome their emotions? in facing the crisis of sars, health professionals may make efforts to combat the enemy like in the war. however, could we regard the hcw as a soldier in an army, as quoted in a china daily report? 7 when the health staffs or soldiers decided to resign from their job just in the moment of crisis/war, some cultures attempt to remind the persons of their sworn duties to contribute to national security by giving the person a feather (sign of shame). while the ethical ideal of self-less sacrifice of life for curing disease is promoted in the public image and media, discussions with hcw in several countries suggests that being a hero is not what modern medical practice is for some hcws. most hcws in taiwan are working in the commercial hospital, where the hirer pushes them to focus their effort of work on business competition rather than the basic role of helpers to human's health. beside academic achievement, the profit they can make for their institute is the element to promote their position in their profession. it is easy to loss the ideas of being heroes that is part of the intrinsic nature of being doctors or nurses. most modern hospitals there are designed under the intention of attracting people to visit frequently. besides for a commercial hospital, the most effective way to limit the budget is to reduce labour costs. to use part time staffs saves much money from less benefit and salary pay. could we expect nurses who were called when they are needed and paid by working hour to devote themselves to the full professional code and make all efforts when their life is threatened? it is obvious that the feeling of belonging and sense of nobility are essential for a professional worker, the problem is do we really respect those health worker as health profession to supply the components to achieve the sense of a professional. many hcw in modern times have only faced remote fears of death, and it is a shock for many to realize that their own lives are in danger. when they considered that even with necessary precaution; they still had to run a certain amount of risk, their duties of being a wife/husband, mother/father or daughter/son will call them home. although sars was reported to have a relatively low mortality rate, it attacks the young and healthy as well as the old and frail. moreover, this is a totally new disease, we know very little about it. the fear and worry of being infected will always be a shadow to their care. will the public accept a health professional to exercise their right to remain off the job in this critical moment? every person of any profession has their personal role in a family to be a father, mother, spouse and child, in addition to their professional roles. the constitution of most countries respect a person's human rights and ego (beyond the superego) i.e. ego is the basic human nature which should be honored too. part of the love of life that makes a bioethics of an ethical person in ethical theories is self-love, not just love of others. those medical practitioners who stick to their post should be respected; however, those who need to take a break to recover themselves would also be acting within their human rights and what is expected of a reasonable citizen. there are cases recorded where doctors spent weeks continuously battling the disease, and there is need for a proper assessment of how fatigue may have led to mistakes in care for patients and mistakes in precautions of carers. there is a human limit for everyone to cope with. those who battled self-lessly are called exceptions, for example, ye xin, 47, head nurse at the guangdong hospital of traditional chinese medicine, died in march after contracting sars while treating patients infected with the virus. ye, together with nine other nurses, was posthumously awarded the florence nightingale prize by the international committee of the red cross in may for 'courage and dedication in the line of duty'. 8 in carrying out the responsibility of reporting the truth, the media created the sars panic. in most of the infected areas, the government had no control over the media. under the pressure of commercial competition, those narratives reported by media could be exaggerated which cause mass panic and changed the relationships between people. on the contrary there was a lack of information in mainland china especially until 20 april, when the government was attempting to limit panic by controlling the media. however, when the epidemic was revealed, the following month saw panic there also. everywhere society has to pay a price for liberty of the media, and to deal with the result of transparent reporting. there were also rumours spread through the internet that generated fear. 9 there are reports that in china 117 people were charged with spreading 'sars-related rumours', though the exact nature of the types of email they were sending is doubted. 10 however, without media reporting as a way to educate society, the death toll everywhere would have been higher. the media generated fear, stigma and discrimination, but also showed the evil sides of the panics. people who were subjects of discrimination included those working in the hospital or entering and coming back from infected areas, suspected sars patients and their family. even those with very common syndromes of cold (cough, fever, etc.) were psychologically and socially isolated by their friends and relatives. from the narratives reported by media, the mass panic caused by sars has changed the relationships between people. in certain cases by calling health professionals 'heroes' policy makers in government wanted to escape from their guilt of policy mistakes by giving ambiguous honors. governments had to face up to the mass fear that sars created, and any target could be chosen. there were scapegoats in mainland china on the 20 april with the firing of the health minister. in many countries affected by sars, and neighbours like japan, one of the usual targets for blame is foreigners. persons from distant lands have always been blamed in cases of disease. 11 in early april, a hong kong resident came to taiwan to visit his younger brother despite being supposed to be under home isolation in hong kong due to the spread of the disease in his apartment building, amoy garden. his brother was infected by him and it was the first fatal case of sars in taiwan. one woman, who took the same train with him, was highly suspected to be the source of a major hospital outbreak. at first, the doctors were not sensitive about her case since she had no contact history to match the susceptive criteria for sars. thus, she spread sars in the hospital before she was diagnosed. many hospital staff, patients and patients' families were infected at the same time. the hospital was able to detect this spread and sealed its premises entirely without good preparation. four thousand people were locked inside the building to prevent further spread of the disease; and more than 30 000 people were isolated in their homes. this strong measure resulted in a mass panic. but it was too late. the numbers of infected cases increased exponentially. inside china, the people in guangzhou province are blamed. when one of us was in beijing on 19 april, 2003, some experts said 'the people in guangzhou eat anything that moves. it is their fault.' people in hong kong may have blamed the chinese. people in taiwan or canada blamed those from hong kong. people in japan in may blamed a doctor who traveled from taiwan who later came down with sars. all the people they blamed were just being human, but foreigners are convenient targets. the chinese government was so concerned about the image of china that it is rumoured that persons were threatened by death in case they transmitted the disease to foreign countries. 10 if we view the work of medicine a sacred vocation, an inner calling to dedicate and care for the sick, it is contradictory to imagine some medical doctors may be accused of giving rise to a great loss of our society. taiwanese society decided to punish some of the head doctors who did not detect and report the hospital infection in the early stage. the final decision was to give the very tough punishment of retracting their professional license. ethically a wrong decision should not be punished as a crime of that magnitude unless the health profession had a criminal intention (motivation). although the consequences were a great loss for society it is not a wise move for the future to punish physicians for making mistaken decisions in emergency circumstances over public health if they were not intending any cover-up. there seems to be a threat of political scapegoats in every health crisis. we can expect future hcws to move for greater self-protection and hesitance in making decisions that are necessary for public health crises like emerging diseases. between the hero and the coward, there must have some space where people can be humane. it is normal and proper for people to be scared to die yet fulfill their duty in the frontline. except for special 'danger pay' or another kind of reimbursement, a calling for increased emphasis on workplace safety and a review of precautions is most important for this critical situation. a well trained and equipped health worker also needs to prepare for the frontline of possible bioterrorism, which may be similar to what we saw with sars. we need a well prepared expert more than a hero. there were cases reported where proper diagnosis of other diseases was hindered by the infection prevention measures being applied to treat all patients from sars infected areas as potential sars victims. 12 spiritual motivation should not slacken the implementation of sound precautionary measures. as the who director-general said 'the containment of sars required heroic efforts and extraordinary measures that are difficult to sustain over time'. 13 a taiwanese study of nurses in may-june 2003 found that nurses' agreement with the government control measures was a predictor of the extent to which they fulfilled their professional care obligation. 14 this suggests that having the support of the healthcare professions in policy is essential for everyone to work wholeheartedly. before the next outbreak, we need long-term planning and humane intervention to prepare a better response for the expected return of the disease. in the future if some repressive regimes are hit by sars they might employ brutal tactics to quarantine and isolate people, possibly sowing division among outside countries and multilateral organizations over how to respond to apparent human rights violations. 15 calls for development of effective centers for disease control in other regions of the world, including europe, have been made in response to the ways sars was fought. 16 the intention of calling for hcws to above all do good should not be blurred by wrong planning. with sars as with other severe infectious diseases that are readily transmitted, the manner that home and work isolation is handled is a key ethical issue. if people were diagnosed to be suspect or probable cases, all the people around them may as well be suspected of having been contaminated by them. consequently, the persons they have been in close contact with, for example, families, colleagues or schoolmates may be isolated to avoid further possible spread of the disease. such home isolation has serious social and psychological influences. in some cases, those who break home isolation may be punished by imposing a fine. people who were victims of sars in 2003 were accused of hindering the prevention or treatment of sudden disease outbreaks if they broke such isolation. it is normal to expect that quarantine will cause fears, and people will lose their patience and self-restraint, but we should assume that all people were originally infected by others with a few recent exceptions infected by laboratory medical research. persons should be taken care of better than being totally restricted to avoid them inflicting possible harm on others. with the policy of respecting human individuals complete needs for physical and mental well being, more people will be motivated not just to protect themselves, but to contribute to the macro wellbeing of the society. there are still lessons for all in society about the ethics of quarantine. modern society has forgotten the past risks of infectious disease outbreaks. we would suggest to respect health worker's autonomy of making their own choice to take a break from intensive physical or emotional loading or to accomplish the historical mission of coping with sars. a well developed society that we live in should have sufficient space to practice humanism to everyone in any kind of situation including a public health crisis. this is one of the lessons, we should learn in preparation for the next crisis of infectious disease. world health organization, summary table of sars cases by country an ebola epidemic simmers in africa sars: an asian catastrophe which has challenged the relationships between people in society-my experience in taiwan what have we experienced and learned from the outbreak of sars in beijing? flying publisher editorial: three lessons of sars too soon to celebrate the foreignness of germs: the persistent association of immigrants and disease in american society nurses' professional care obligation and their attitudes towards sars infection control measures in taiwan during and after the 2003 epidemic sars: down but still a threat. scope note (u) united states national intelligence center severe acute respiratory syndrome (sars): loud clang of the leper's bell key: cord-262653-v1to1mrp authors: asad, h.; johnston, c.; blyth, i.; holborow, a.; bone, a.; porter, l.; tidswell, p.; healy, b. title: health care workers and patients as trojan horses: a covid19 ward outbreak date: 2020-07-04 journal: nan doi: 10.1016/j.infpip.2020.100073 sha: doc_id: 262653 cord_uid: v1to1mrp summary background transmission in healthcare settings can result in significant infections in healthcare workers and patients. understanding infection dynamics has important implications for methods employed in hospitals to prevent nosocomial-transmission events. methods in this case series report we describe a cluster of covid-19 (coronavirus disease 2019) in a tertiary care university hospital, in the early phases of the epidemic, after hospital visiting had been stopped and when the uk lockdown was in place. findings a 48 year old patient developed covid-19 31 days post-admission and four days after admission to a medical ward from itu. infection was likely acquired from an asymptomatic or minimally symptomatic healthcare worker (hcw). subsequent investigation over a 14 day period revealed symptoms in 23 staff members and five linked cases in patients on the same ward. nine of the 23 affected staff members provided care for and had direct exposure with the index case. four staff reported caring for the index case without use of personal protective equipment. one was coughed on directly by the patient 24 hours prior to the onset of symptoms. conclusion sars cov2 infection can be introduced to a ward area by asymptomatic and minimally symptomatic healthcare workers. staff members and patients can act as trojan horses carrying infection into and around the hospital, setting up unexpected transmission events. transmission of infection from pre-symptomatic, asymptomatic and minimally symptomatic individuals means that universal use of measures to prevent transmission is required for successful reduction of transmission events in the hospital setting. coronaviruses are a large family of enveloped rna viruses including aetiological agents of the common cold, severe acute respiratory syndrome (sars) infection caused by severe acute respiratory syndrome coronavirus 2 (sars-cov-2) -a betacoronavirus. transmission within healthcare settings is an important area of study as it can result in significant infections in healthcare workers (hcw), disrupt the workforce and affect vulnerable individuals. recognition that hcw can act as points of introduction of covid-19 into the healthcare setting has important implications for infection control methods employed in hospitals. the transmission rate amongst healthcare personnel also has implications for the hospital environment and the way that staff interact with patients and with each other. we report on a cluster of covid-19 (coronavirus disease 2019) in a tertiary care university hospital, in the early phases of the epidemic in this region. the objective of this report was to describe the epidemiological investigation carried out to identify the transmission routes and source of infection. the infections began after hospital visitations had been stopped and around the time of the uk lockdown which began officially on 23 rd march 2020. the cluster was associated with a patient that had acquired infection whilst in hospital, most likely from an asymptomatic or minimally symptomatic hcw. subsequent transmission events resulted in a number of nosocomial transmissions and a high rate of infection amongst staff. a detailed investigation was carried out on a cluster of infections affecting staff and patients on a medical ward. additional patient and staff cases epidemiologically linked to the outbreak were identified using a local clinical surveillance software, icnet, and by obtaining routine staff self-isolation data. an in house real time pcr assay for covid-19 was carried out on dry throat swabs taken from symptomatic patients and staff members working on the ward. demographic and clinical characteristics, details of symptoms experienced and symptom onset were prospectively collected for all patients from medical records, icnet and interviewing ward staff. symptoms experienced and onset date were obtained by carrying out telephone interviews of all affected hcw. patient cases were defined as individuals with (a) a laboratory confirmed covid-19 diagnosis (b) absence of covid-19 compatible symptoms at the time of admission and infection 48 hour post hospital admission and (c) a hospital admission that overlapped with a confirmed patient or hcw case suggesting direct or indirect contact with the index case. hcw cases were defined as (a) a member of staff from the affected ward and (b) compatible symptoms for covid-19 (c) onset of infection during the outbreak period. hcw's were further classified as hcw case e pcr detected, likely hcw case -not swabbed, likely hcw case -pcr not detected. the analyses in this paper covered patients and hcw identified from 31/03/2020e14/04/2020. collected data were securely stored on a secure network drive managed by public health wales. the data were cleaned using stata version 14.2. the epidemiological curve and ticl chart outputs were generated with r studio version 3.5.1. the index case (case 1) was a 48 year old patient admitted in early 2020 with an unrelated disseminated bacterial infection requiring itu admission. they were discharged from itu to a medical ward 36 days after admission. at the point of admission to the ward they were afebrile, had a tracheostomy in situ and were coughing. 40 days in to their admission and four days after their admission to the medical ward (whilst asymptomatic) they became lymphopenic. one day later they developed a maculopapular rash and became tachypnoeic, febrile and tachycardic, with a news score of 12. at this point, covid-19 was suspected and a throat swab taken that day was positive for sars cov2 by pcr (in house assay). it is likely that the patient acquired the infection around the time of discharge from itu, most probably from an asymptomatic or minimally symptomatic hcw, although transmission from an unrecognised patient cannot be ruled out. pre-symptomatic transmission is well recognised. the period of infectivity for this patient likely began two to three days before the onset of their illness and one to two days after arrival on the medical ward. subsequent investigation over a 14 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 day period revealed 23 symptomatic staff members from the same medical ward ( figure 2 ). two patients in the same bay and two other patients in a neighbouring bay developed symptoms and tested positive three days after covid-19 was detected in the index case. one other patient on the same ward developed symptoms and tested positive 11 days after it was detected in the index case. symptoms are detailed in table 1 . over a 12 day period, spanning from six days before to six days after onset in the index case, there were 17 staff from the itu self-isolating at home due to symptoms compatible with covid-19 ( figure 1 ). of the 23 hcw cases from the affected medical ward, 16 had sars cov2 detected on a throat swab, three were not detected and four were not swabbed. of the three staff in whom the virus was not detected two had symptoms of cough and chest pain (one also had myalgia and chills) and one had fever, myalgia, sore throat and reduced smell and taste (table 1) . they all had exposure to known positive cases and are likely to represent clinically false negative tests. of the four staff that were not swabbed three were symptomatic early in the cluster. one had a fever and cough, one loss of taste and headache, one was shivery, tired with a sore throat and cough. the fourth was symptomatic later on but was unable to drive to get tested (fever, cough, diarrhoea and vomiting). based on their symptoms and exposure history all were likely cases of covid-19. of the 23 affected staff members nine cared for and had direct exposure with the index case (seven based on the working roster and five based on verbal reports from the exposed staff at the time their sample was taken, three of whom were also picked up by the duty roster). four of the five staff members with very early onset of infection were working with the index case during the likely infectious period ( figure 3 ). one staff member who became unwell 24 hours 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 after exposure was coughed on directly by the index case whilst not wearing any personal protective equipment. whilst there is no record of any contact for the fifth staff member from the roster, the staff member verbally reported contact with positive staff and symptomatic patients on the ward. three staff reported caring for the index case without use of personal protective equipment (the ward was considered a negative ward and personal protective equipment (fluid repellent surgical face masks, eye protection, aprons and gloves) was not in routine use in accordance with public health england guidelines at the time). the index case was swabbed four days after admission to the medical ward. a total of four other patient cases were identified on the affected ward with a patient attack rate of 9.8% (6/ 61). of the five linked positive patient cases, four became symptomatic and tested positive three days after the infection was identified in the index case. two were from the same bay and two from a neighbouring bay (figure 3) . a further patient who developed symptoms and tested positive eleven days after the infection was identified in the index case had been admitted 13 days earlier with lethargy, difficulty swallowing, dehydration and general decline. they likely acquired infection during their admission in the affected ward. they had been swabbed as a "possible exposed" patient and tested negative for sarscov2 five days into admission. the cluster of infections spread over 14 days. not all staff or patients had direct contact with the index case. it is likely that the infection was propagated through the ward by further transmission events from pre-symptomatic, minimally symptomatic and asymptomatic staff. the hospital environment is crowded and it is difficult for staff to practice social distancing effectively in the hospital. the ward is made up of four cubicles 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 (no en-suite facilities), two five bedded bays, two six-bedded bays, one four-bedded bay and five shared toilets. there is an atrium area that contains a single shared desk which is often busy and crowded. the ward contains one small room (4m x 4m) where staff would sometimes congregate for short breaks (the ward is a significant distance from the canteen). close contact between staff is common when working at the main ward desk, during breaks in crowded and small break rooms and during routine patient care. the significant number of staff cases is likely related to these factors along with the lack of universal use of personal protective equipment for patient care at this time. hand hygiene compliance on the ward at this time (carried out monthly) were 100%. credit for cleaning scores were 96%. four out of six asymptomatic staff identified from the affected medical ward were swabbed at the end of the outbreak and all tested negative. in total 23 out of 29 staff on the ward developed covid-19 infection over a 14 day period. this rate of infection far exceeded the number of infections on other wards and in the community at the time and is extremely unlikely to have occurred by chance. coronavirus was first identified following an outbreak of pneumonia in wuhan city, hubei province, china, in december 2019 [1] . it is transmitted from person to person highly effectively. human transmission is thought to occur predominately via close contact with respiratory droplets produced when a person exhales, sneezes, or coughs, or via contact with fomites. airborne transmission is possible in specific circumstances such as when aerosol generating procedures are performed; e.g. endotracheal intubation. some data suggests that airborne transmission during routine patient care may also be possible. however, based on the available evidence, who currently recommends droplet and contact precautions for those people caring for covid-19 patients. airborne precautions are recommended only in circumstances and settings when aerosol generating procedures are performed. nosocomial transmission is well recognised [2] . transmission from individuals is variable and is likely related to specific factors of the host and their contacts. some individuals appear to transmit the infection relatively unreadily. others seem to be highly effective transmitters. multiple super-spreading events have been reported. these events are associated with explosive growth early in an outbreak and sustained transmission in later stages [3] . super-spreaders can pass the infection on to large numbers of contacts, including hcw. super-spreaders are a well-recognised phenomenon. the 20:80 rule suggests that 80% of infections are caused by 20% of infected individuals that spread infection most readily [4] . transmission from asymptomatic and pre-symptomatic individuals is also well recognised. estimates of asymptomatic infection range from 18% (modelling study from the diamond princess cruise ship) [5] to 31% (japanese study of citizens evacuated from wuhan city) [6] to 50e75% (data from an isolated village of 3000 people in italy) [7] . pre-symptomatic transmission has been reported in 12.6% of cases [8] and has been predicted to account for 44% of infections [9] . transmission during the incubation period has also been described [10] . the incubation period ranges from 1 to 14 days [11] . the median incubation period has been estimated to be approximately 5 days [12, 13] . the case fatality rate of covid-19 is known to increase with age [13] and with the presence of comorbidities [14] . activity in the hospital had been significantly reduced in the period leading up to these outbreaks. patients remaining in hospital at this time were therefore vulnerable to severe infection with covid-19 and at higher risk of a poor outcome because of the presence of co-morbidities. the strengths of this report are the in depth description of a well-defined cluster of infections in a hospital setting during the early phases of the sars-cov2 epidemic that capture many of the features that make coronavirus difficult to contain. the report provides valuable lessons that are crucial to containing this infection as well as other viral infections in the healthcare setting (the consequences of which likely often go unnoticed) and in terms of preparing for future pandemic threats. the limitations include the inability to exactly track the modes of transmission from one individual to another during this outbreak and consequently to identify which prevention measure have the greatest impact in terms of preventing similar events in the future. the outbreak reported in this paper demonstrate several features. firstly, sars-cov2 infection can be introduced to a ward area by asymptomatic and minimally symptomatic hcw. hcw and patients can act as trojan horses carrying infection into and around the hospital, setting up unexpected transmission events. in this case infection was most likely introduced by an asymptomatic or minimally symptomatic hcw and then transferred via a longstanding patient from itu to a previously negative medical ward. secondly, recognition is less likely when patients acquire covid-19 in hospital and particularly during the early phases of the epidemic. a high level of suspicion for covid-19 is required to reduce the risks posed by this type of event, even when rates of infection in the area and hospital are low. hcw need to have a low threshold for testing and be vigilant for clues such as cxr changes, low lymphocyte count, fever, cough and viral illness. thirdly, at this time of limited herd resistance, infection is transmitted highly effectively from staff-to-patient, patientto-patient and staff-to-staff. consequently, infection can be rapidly amplified in the hospital setting. this is compounded by cramped conditions in the hospital, including small rest rooms and staff communal areas that impair attempts to contain infection and facilitate staff-to-staff spread. staff shortages and lack of redundancy in the system also encourage staff members to work when unwell. this stoicism, that is an important part of maintaining function of the nhs, causes significant problems in terms of in-hospital transmission of infection to vulnerable patients and other staff members. this phenomenon is more easily recognised and more damaging during this pandemic because of the lack of herd immunity, high attack rate and high case fatality rate of the novel pathogen sarscov2. as such, early recognition of covid-19 (with a robust test and trace system) combined with high levels of compliance with the use of preventative measures (a combination of social 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 distancing, compliance with infection, prevention and control precautions e e.g. hand hygiene and cough hygiene and appropriate routine use of personal protective equipment) is required to reduce the threat posed by covid-19 in the hospital environment and is crucial to prevent un-curtailed transmission events in the hospital setting. the presence of transmission of infection from pre-symptomatic, asymptomatic and minimally symptomatic individuals means that routine use of all of the above precautions is required for successful reduction/prevention of transmission events in the hospital setting. where possible liberal use of masks to reduce transmission from asymptomatic, pre-symptomatic and minimally symptomatic infected individuals (staff and patients) to others (staff and patients) should be encouraged. all authors declare no conflict of interest. the authors received no financial support to carry out this work. this report contains information collected as part of routine management of an outbreak and as such ethical approval was not required. the report has been reviewed by the health board ethical department and approved for submission. the manuscript has been reviewed by the health board information governance department, who confirmed the report is compliant with information governance standards. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 identification of a novel coronavirus causing severe pneumonia in human: a descriptive study presymptomatic sars-cov-2 infections and transmission in a skilled nursing facility identifying and interrupting superspreading events-implications for control of severe acute respiratory syndrome coronavirus 2. emerg infect dis super-spreaders in infectious diseases estimating the asymptomatic proportion of coronavirus disease 2019 (covid-19) cases on board the diamond princess cruise ship estimation of the asymptomatic ratio of novel coronavirus infections (covid-19) covid-19: identifying and isolating asymptomatic people helped eliminate virus in italian village serial interval of covid-19 among publicly reported confirmed cases temporal dynamics in viral shedding and transmissibility of covid19 a familial cluster of infection associated with the 2019 novel coronavirus indicating possible person-to-person transmission during the incubation period the incubation period of coronavirus disease 2019 (covid-19) from publicly reported confirmed cases: estimation and application early transmission dynamics in wuhan, china, of novel coronavirus-infected pneumonia estimates of the severity of coronavirus disease 2019: a model based analysis comorbidity and its impact on 1590 patients with covid-19 in china: a nationwide analysis key: cord-264522-u61m4x9l authors: crupi, robert s.; di john, david; mangubat, peter michael; asnis, deborah; devera, jaime; maguire, paul; palevsky, sheila l. title: linking emergency preparedness and health care worker vaccination against influenza: a novel approach date: 2016-11-16 journal: jt comm j qual patient saf doi: 10.1016/s1553-7250(10)36073-9 sha: doc_id: 264522 cord_uid: u61m4x9l background: health care workers (hcws) can acquire and transmit influenza to their patients and coworkers, even while asymptomatic. the u.s. healthy people 2010 initiative set a national goal of 60% coverage for hcw influenza vaccination by 2010. yet vaccination rates remain low. in the 2008–2009 influenza season, flushing hospital medical center (fhmc; new york) adopted a “push/pull” point-of-dispensing (pod) vaccination model that was derived from emergency preparedness planning for mass vaccination and/or prophylaxis to respond to an infectious disease outbreak, whether occurring naturally or due to bioterrorism. launch of the hcw vaccination program: in mid-september 2008, a two-week hcw vaccination program was launched using a sequential pod approach. in push pod, teams assigned to specific patient units educated all hcws about influenza vaccination and offered on-site vaccination; vaccinated hcws received a 2009 identification (id) validation sticker. in pull pod, hcws could enter the hospital only through one entrance; all other employee entrances were “locked down.” a 2009 id validation sticker was required for entry and to punch in for duty. employees without the new validation sticker were directed to a nearby vaccination team. after the push/pull pod was completed, the employee vaccination drive at fhmc was continued for the remainder of the influenza season by the employee health service. results: using this model, in two days 72% of the employees were reached, with 54% of those reached accepting vaccination. conclusions: this model provides a novel approach for institutions to improve their hcw influenza vaccination rates within a limited period through exercising emergency preparedness plans for infectious disease outbreaks. w ho watches the watchers?" was a phrase rendered from the "satires" of the ancient roman poet juvenal. 1 health care workers (hcws) are supposed to be the watchers of our health, helping ensure that we all stay healthy and that diseases are contained and not spread to others. even though influenza vaccination has been found to be the single most important measure for preventing hospital-acquired influenza, hcws continue to have low vaccination rates. 2 in november 2000 the u.s. department of health & human services published a health promotion and disease prevention initiative, healthy people 2010, establishing a goal of a 60% rate for influenza vaccination of hcws by 2010. 3 yet, the national vaccination rate for hcws remains at unacceptably low levels: 38% in the 1999-2000 influenza season, 42% in 2005-2006, 44% in 2006-2007, and 49% in 2007-2008 . [4] [5] [6] [7] in 2006, in an attempt to address the failure to improve hcw vaccination rates, the u.s. centers for disease control and prevention (cdc) published recommendations, which focused on three strategies: educating hcws about benefits of vaccination; providing annual, free on-site vaccination; and obtaining signed declination forms for vaccine refusers. 8, 9 also in 2006, the joint commission established a new infection control standard for influenza vaccination of hcws that included education, on-site access to vaccination, and ongoing program evaluation to improve hcw participation. 9 -12 * health care institutions have attempted to increase their immunization rates using a variety of methods: education, reminder notices, providing small incentives, establishing easy access to free vaccination, active promotion of vaccination within the workplace, and/or compulsory vaccination as a condition of employment. [13] [14] [15] except for mandatory programs that have achieved vaccination acceptance rates as high as 98.4% article-at-a-glance background: health care workers (hcws) can acquire and transmit influenza to their patients and coworkers, even while asymptomatic. the u.s. healthy people 2010 initiative set a national goal of 60% coverage for hcw influenza vaccination by 2010. yet vaccination rates remain low. in the 2008-2009 influenza season, flushing hospital medi cal center (fhmc; new york) adopted a "push/pull" point-ofdispensing (pod) vaccination model that was derived from emergency preparedness planning for mass vaccination and/or prophylaxis to respond to an infectious disease outbreak, whether occurring naturally or due to bioterrorism. launch of the hcw vaccination program: in mid-september 2008, a two-week hcw vaccination program was launched using a sequential pod approach. in push pod, teams assigned to specific patient units educated all hcws about influenza vaccination and offered on-site vaccination; vaccinated hcws received a 2009 identification (id) validation sticker. in pull pod, hcws could enter the hospital only through one entrance; all other employee entrances were "locked down." a 2009 id validation sticker was required for entry and to punch in for duty. employees without the new validation sticker were directed to a nearby vaccination team. after the push/pull pod was completed, the employee vaccination drive at fhmc was continued for the remainder of the influenza season by the employee health service. results: using this model, in two days 72% of the employees were reached, with 54% of those reached accepting vaccination. conclusions: this model provides a novel approach for institutions to improve their hcw influenza vaccination rates within a limited period through exercising emergency preparedness plans for infectious disease outbreaks. * standard ic 02.04.01: the hospital offers vaccination against influenza to licensed independent practitioners and staff. element of performance 3: the hospital provides influenza vaccination at sites accessible to licensed independent practitioners and staff (ic-12-ic-13). the joint commission journal on quality and patient safety under threat of termination, most employment-related programs have achieved only small increases in immunization rates. [16] [17] [18] at our institution, implementing some of these methods resulted in only modest gains in hcw vaccination rates, with an acceptance rate of only 38% in the 2006-2007 vaccination season. 19 as a result, we decided to employ an emergency preparedness model as the primary means for vaccinating our employees in the 2008-2009 season. 20 interest in the ability to recognize and respond to a bioterrorism or naturally occurring event has intensified during the past years. exercises have focused on problems that hospitals would face with respect to (1) leadership and decision making, (2) prioritization and distribution of antibiotics and vaccines, and (3) applying principles of disease containment, including facility lockdown. 21 recent events, including the emergence of severe acute respiratory syndrome (sars) in november 2002 to july 2003, concerns over avian influenza, and, most recently, pandemic h1n1 influenza, have prompted hospitals to reappraise their emergency preparedness plans. however, regular drilling of such plans to challenge their inherent assumptions is often lacking, giving rise to a false sense of security known as the "paper plan syndrome." 22, 23 modification of emergency preparedness plans through drills and exercises is required to render them more effective. 24 at our institution, the decision to link the hcw influenza vaccination program to exercising our emergency preparedness plan was viewed as an opportunity to enhance the effectiveness of both. in this article, we report on the use of a novel program to increase influenza vaccination rates of hcws at a community hospital by exercising its emergency preparedness plans for mass vaccination and/or prophylaxis for infectious disease outbreaks as a model for improvement of both employee vaccination rates and emergency preparedness. the flushing hospital medical center (fhmc) in flushing, new york, is an urban, 325-bed, acute care community hospital with 1,642 employees, situated in a culturally diverse neighborhood of new york city. in 2008, our full-service emergency department (ed) treated 45,200 patients; our outpatient departments saw 114,000 patients. in mid-september 2008, we launched our hcw vaccination program with a widely disseminated, facility-based educational campaign about seasonal influenza vaccination that used informational pamphlets, posters, and workshops in a twoweek period. at the campaign's conclusion, we initiated, with no advance notification, influenza vaccination efforts using a sequential "push/pull" point-of-dispensing (pod) approach. the push pod. push refers to actively offering vaccination at locations to which employees are assigned to work. for the purpose of our program, we defined all hospital employees as hcws because we believe that interaction between employees, patients, and visitors places all at potential risk of acquiring and spreading influenza. applying the incident command system (ics) model derived from emergency preparedness planning, vaccination teams established by the nursing department and assigned to specific patient units reported to the command center at 8:00 a.m. (8:00) on the day of the push pod. 20, 25 before deployment, each team was given a 30-minute focused in-service on dissemination of vaccine information to potential recipients, the use of permission/declination forms, and vaccine administration. on arrival in each clinical unit or office, the vaccination teams briefly educated all hcws about the importance of influenza vaccination and offered on-site vaccination to those who consented. there was no cost to the employee. those who declined vaccine for any reason were required to sign a declination form. only after vaccination or signing the declination form was a 2009 validation sticker placed on the hcw's identification (id) badge to easily identify employees already screened. the teams reported back to the command center after all employees present on the assigned units were reached, a process that took about 90 minutes. data for employees reached, vaccinated, or declining vaccination were recorded. assigned push pod teams reported to the command center at 4:00 p.m. (16:00) and again at midnight (24:00) to cover all working shifts: all components of the program were repeated. the pull pod. pull refers to the process of actively identifying hcws who were not reached during the push phase the previous day. in this second phase, between 6:00 a.m. (6:00) and 9:30 a.m (9:30), hcws could enter the hospital only through one entrance. all other employee entrances were "locked down" in compliance with the new york city building fire code regulations. at our institution, all employees-including physicians and management-are required to punch in at the beginning of their shift. electronic time-clock punch-in devices in the facility were disabled except for the one nearest to this open employee entrance. a 2009 id validation sticker was required for entry and to punch in for duty. those employees without the sticker were directed to a nearby vaccination team. vaccine was administered or the hcw was required to sign a declination form. only then could the hcw receive an id validation sticker and be allowed entry into the facility. after the two-day program, the data for the number of doses of vaccine administered and declination forms signed were tabulated using microsoft excel 2007. after the push/pull pod was completed, the employee vaccination drive at fhmc was continued for the remainder of the influenza season by the employee health service (ehs). as a result of this two-day exercise, 1,181 (72%) of the 1,642 total employees of our institution were reached. as shown in table 1 (above), the push pod phase reached 871 of fhmc employees (53%), with 520 (60%) accepting influenza vaccine. during the pull pod, an additional 310 hcws (19%) were reached, of whom 118 (38%) were vaccinated (table 1) . together, the two-day push/pull pod drill achieved a vaccination rate of 54% among the 1,181 employees who were reached, representing 39% (638/1,642) of all hcws (table 1 and table 2 [right]). for 2008-2009, the overall hcw influenza vaccination rate for fhmc was 56%, which included vaccinations offered by the ehs following the two-day push/pull pod and documented vaccinations received outside fhmc (table 2 ). this rate was significantly higher (p < .001) than the 38% rate for the 2006-2007 season ( table 3 , right). the push/pull pod plan we have described for influenza vaccination of hcws in 2008-2009 was initially devised as part of our emergency preparedness/drilling for mass immunization/ prophylaxis for infectious disease outbreaks. the linkage of our emergency response plan with improvement in hcw influenza vaccination rates is a unique approach that can enhance the effectiveness of both programs. using components of our emergency preparedness plans, including the ics model, we were able to reach 72% of hospital employees and vaccinate 39% of our total workforce in a two-day period, nearly achieving the national average for seasonal influenza vaccination of hcws within that limited time frame. with respect to emergency preparedness planning, the initiative offered an opportunity to organize, execute, and evaluate performance for mass vaccination/prophylaxis in the context of a drill. during the push phase, the incident manager of the ics was able to monitor the deployment and success of vaccination teams in real a novel feature of our program was the facility lockdown in the pull pod. limiting access to the facility as well as restricting access to the device required to clock in for work only to those employees who had been issued id validation stickers during the push pod for either having received or declined influenza vaccine proved to be a successful method for identifying, reaching, and vaccinating additional hcws. the use of mobile vaccination teams is an important and effective method to increase hcw influenza vaccination rates. 26 such teams engage in face-to-face interactions with hcws to specifically address their questions and concerns, potentially resulting in an increased acceptance of influenza vaccination. 9 hcws might also be positively influenced by observing their coworkers accepting vaccination. the process also offered the advantages of employee convenience, avoidance of staffing disruptions, and no cost to the employee. the pull pod phase of our vaccination program, involving a facility lockdown as part of emergency preparedness planning response to infectious disease outbreaks, is to our knowledge and a review of the literature, a novel approach in reaching employees. although our pilot lockdown of 2½ hours during a single weekday morning work-shift change was only a brief test, we were successful in reaching employees not encountered in the push pod. although many hcws declined vaccination in this pull phase, vaccination declinations had to be signed to clock in for work. future exercise planning would determine if additional or longer lock-down periods at different shift times can be implemented at our busy urban community hospital. for larger institutions, the manner or feasibility of implementation of the pull pod needs to be considered. our data set only identified whether or not hcws were vaccinated; those who were not vaccinated signed a declination. although this study was not designed to examine vaccine refusal, reasons for declination were obtained. the most common reasons cited were fear of side effects and the belief that the vaccine was ineffective. these findings are consistent with other studies. 7 addressing the reasons for declination would help refine and focus educational efforts to help increase hcw vaccination rates in the future. we did not report on the 2009-2010 vaccination season, given the unusual circumstances of that influenza season. new york state had instituted mandatory influenza vaccination for hcws, only to later suspend the mandate because of disruptions in vaccine supply for both seasonal influenza and mono-valent h1n1 vaccine. some reluctant hcws agreed to be vaccinated because of the original mandate, whereas others withheld their consent while awaiting results of legal challenges. there was also anxiety expressed by some hcws over receiving two vaccinations. in particular, concerns over the "newness" of the h1n1 vaccine and recollections of problems associated with "swine flu" vaccine in 1976 might have had a crossover effect in creating or reinforcing negative perceptions about influenza vaccines in general. the challenge of achieving and maintaining high annual hcw influenza vaccination rates in the absence of a requirement for vaccination necessitates a multifaceted approach. mandatory vaccination is increasingly being recommended by professional organizations, including the society for healthcare epidemiology of america, the infectious diseases society of america and the american academy of pediatrics. [27] [28] [29] however, even if such mandates succeeded in achieving high influenza vaccination rates among hcws, there would still be the need to regularly exercise emergency preparedness plans for mass vaccination or prophylaxis in preparation for other potential infectious disease threats. 21, 30 the emergency preparedness plan as exercised tested our inherent assumptions and succeeded in reaching a majority of our employees over a limited time frame. the plan was executed without altering staffing patterns and allowed for real patients to receive care without interruption. the exercise demonstrated the ability of our ics to successfully deploy multidisciplinary teams and monitor their activities, to rapidly screen hcws, to efficiently distribute vaccine, and to collect measurable data on performance to drive the process. the push/pull pod model derived from emergency preparedness planning is an effective tool for improving influenza vaccination rates among hcws. the addition of our pull pod, that is, the lockdown phase of restricting access to the facility, is a unique strategy that was implemented and found to be successful. this model addresses issues of standards of care and performance improvement for hcw influenza vaccination and emergency preparedness planning and drilling for mass vaccination and prophylaxis. we believe that this model can serve as a dual platform for other institutions to improve their hcw vaccination rates and emergency preparedness planning. the ability to reach and offer influenza vaccination to a majority of hcws early in the influenza vaccination season, and to accomplish such vaccination efficiently, allows for targeted initiatives for those hcws most resistant to vaccination. future studies should explore different approaches to the push/pull model as it relates to duration, frequency, sequencing, or separating its components to create best practices that fit the needs of different institutions. mandatory influenza vaccination of hcws would clearly have the most significant impact on improving acceptance rates but would still not obviate the need to regularly exercise emergency preparedness plans in preparation for other potential infectious disease threats. dr. di john is a speaker for sanofi-pasteur, glaxosmithkline, and novartis. preliminary data from this study were presented by dr. crupi and his colleagues at flushing hospital medical center (fhmc) in a poster at the 19th annual scientific meeting of the society for healthcare epidemiology of america (shea), march 19-22, 2009 , in san diego. the authors express their deep gratitude for the efforts of the departments of nursing, pharmacy, employee health, and security, as well as the hospital administration and all fhmc employees for their cooperation in making this study possible. they also thank jane r. zucker, m.d., m.sc., assistant commissioner, bureau of immunization of the new york city department of health and mental hygiene, for her support, 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literature terrorism and disaster management medical society of the state of new york: the emergency management institute's compliance courses on national incident management systems (nims) for physicians use of a mobile cart influenza program for vaccination of hospital employees infectious diseases society of america (idsa): idsa policy: mandatory immunization of health care workers against seasonal and pandemic influenza committee on infectious diseases: policy statement-recommendation for mandatory influenza immunization of all health care personnel. pediatrics, in press meeting the challenges of bioterrorism: lessons learned from west nile virus and anthrax pediatric infectious disease infectious diseases, department of internal medicine is administrator, department of emergency medicine key: cord-261173-lnjh56ts authors: misra-hebert, anita d.; jehi, lara; ji, xinge; nowacki, amy s.; gordon, steven; terpeluk, paul; chung, mina k.; mehra, reena; dell, katherine m.; pennell, nathan; hamilton, aaron; milinovich, alex; kattan, michael w.; young, james b. title: impact of the covid-19 pandemic on healthcare workers’ risk of infection and outcomes in a large, integrated health system date: 2020-09-01 journal: j gen intern med doi: 10.1007/s11606-020-06171-9 sha: doc_id: 261173 cord_uid: lnjh56ts background: understanding the impact of the covid-19 pandemic on healthcare workers (hcw) is crucial. objective: utilizing a health system covid-19 research registry, we assessed hcw risk for covid-19 infection, hospitalization, and intensive care unit (icu) admission. design: retrospective cohort study with overlap propensity score weighting. participants: individuals tested for sars-cov-2 infection in a large academic healthcare system (n = 72,909) from march 8–june 9, 2020, stratified by hcw and patient-facing status. main measures: sars-cov-2 test result, hospitalization, and icu admission for covid-19 infection. key results: of 72,909 individuals tested, 9.0% (551) of 6145 hcw tested positive for sars-cov-2 compared to 6.5% (4353) of 66,764 non-hcw. the hcw were younger than the non-hcw (median age 39.7 vs. 57.5, p < 0.001) with more females (proportion of males 21.5 vs. 44.9%, p < 0.001), higher reporting of covid-19 exposure (72 vs. 17%, p < 0.001), and fewer comorbidities. however, the overlap propensity score weighted proportions were 8.9 vs. 7.7 for hcw vs. non-hcw having a positive test with weighted odds ratio (or) 1.17, 95% confidence interval (ci) 0.99–1.38. among those testing positive, weighted proportions for hospitalization were 7.4 vs. 15.9 for hcw vs. non-hcw with or of 0.42 (ci 0.26–0.66) and for icu admission: 2.2 vs. 4.5 for hcw vs. non-hcw with or of 0.48 (ci 0.20–1.04). those hcw identified as patient facing compared to not had increased odds of a positive sars-cov-2 test (or 1.60, ci 1.08–2.39, proportions 8.6 vs. 5.5), but no statistically significant increase in hospitalization (or 0.88, ci 0.20–3.66, proportions 10.2 vs. 11.4) and icu admission (or 0.34, ci 0.01–3.97, proportions 1.8 vs. 5.2). conclusions: in a large healthcare system, hcw had similar odds for testing sars-cov-2 positive, but lower odds of hospitalization compared to non-hcw. patient-facing hcw had higher odds of a positive test. these results are key to understanding hcw risk mitigation during the covid-19 pandemic. electronic supplementary material: the online version of this article (10.1007/s11606-020-06171-9) contains supplementary material, which is available to authorized users. understanding the risks associated with the covid-19 pandemic 1 on healthcare workers (hcw), including the risk of acquisition at work vs. other settings, is crucial. prediction of risk can inform how to protect hcw such as recommendations on use of personal protective equipment (ppe) at work or in the community. the presence of specific symptoms in hcw (china, usa) 2, 3 and symptoms predicting sars-cov-2 test positivity in hcw (netherlands) 4 has been reported as well as characteristics associated with hcw deaths (china). 5 based upon data from the 2018 national health interview survey, it was estimated that 26.6% of patient-facing hcw were at increased risk for poor outcomes from covid-19 infection because of their comorbidities or age. 6 reported experiences in china, 7 italy, 8 and solano county, ca, without initial use of ppe, 9 showed higher percentages of hcw testing positive for covid19 . in contrast, a screening study of hcw in england showed no significant difference in positive results between electronic supplementary material the online version of this article (https://doi.org/10.1007/s11606-020-06171-9) contains supplementary material, which is available to authorized users. clinical and nonclinical staff with implementation of isolation and ppe protocols perhaps suggesting predominant community rather than nosocomial transmission patterns. 10 the extent of risk modification with ppe remains unclear. [7] [8] [9] 11 a recent prospective study in the uk and usa suggested a fivefold increased risk for hcw caring for patients with covid-19 compared to hcw not caring for patients with covid-19, even with the use of ppe, 12 while another study of hcw in a large healthcare system showed a decrease in positive tests for sars-cov-2 associated with a universal masking recommendation. 13 this heterogeneous landscape makes it difficult for the hcw community to determine actual risk of acquiring covid-19 in healthcare vs. community settings and the effectiveness of various risk-mitigating strategies. the cleveland clinic health system (cchs) is a large, integrated health system with 55,574 eligible employees in ohio and florida. the cchs initiated multiple covid-19related public health initiatives to mitigate the spread of the disease and its impact on the hcw community. in parallel, we maintained a rigorous, comprehensive, and prospective registry capturing disease risk and progression in all individuals tested for covid-19 in our health system. in this study, we aimed to assess whether hcw are at higher risk for covid-19 infection, covid-19-related hospitalization, and intensive care unit (icu) admission compared to non-hcw using advanced statistical methodology to account for various confounders. covid-19 cleveland clinic enterprise registry. all patients, regardless of age, who were tested for covid-19 at all cchs locations in ohio and florida, were included in this research registry. for this study, all individuals who were tested for covid-19 in the cchs between march 8, 2020, and june 9, 2020, were studied. this registry provides better representation of the overall population than testing restricted to one geographic health system site. registry variables were chosen to reflect available literature on covid-19 disease characterization, progression, and proposed treatments, including medications initially thought to have potential for benefit after drug-repurposing network analysis. 14 capture of detailed research data was facilitated by the creation of standardized clinical templates implemented across the healthcare system as patients were seeking care for covid-19-related concerns. data were extracted via previously validated automated feeds from electronic health records 15 (epic; epic systems corporation) and manually by a study team trained on uniform sources for the study variables. study data were collected and managed using redcap electronic data capture tools hosted at the cleveland clinic. 16, 17 the covid-19 research registry team includes a "reviewer" group and a "quality assurance" group. the reviewers were responsible for manually abstracting and entering a subset of variables that cannot be automatically extracted from the electronic health record (ehr). reviewers were also asked to verify high-priority variables that have been automatically pulled into the database from epic. the cleveland clinic institutional review board approved this study and waived the requirements for written informed consent. identification of hcw. individuals were identified as hcw through the cchs occupational health, and their job description was identified as having direct contact with patients or "patient facing" vs. non-patient facing based upon the listing in the cchs human resources database. public health guidelines for cchs employees and availability of testing for covid-19 changed rapidly between march 6, 2020, and april 24, 2020 (appendix 1), the most relevant being the recommendation for universal masking for cchs employees on april 7, 2020, and requirement on april 24, 2020. regarding state public health orders, a stay-at-home order was issued in ohio on march 22, 2020, with phased reopening in may starting with restaurants and bars on may 14, 2020, 18 and in florida, a public health advisory was issued on march 25, 2020, addressing vulnerable populations, private gatherings, and workforce density 19 with reopening beginning on may 18, 2020. 20 all descriptive statistics were reported as counts (percentages) or median (interquartile ranges [iqrs] ). for comparison of demographic variables and comorbidities among cohorts, wilcoxon signed-rank tests were used for numeric variables, while χ 2 or fisher exact tests were used for categorical variables. to address differences in baseline characteristics of non-hcw and hcw, specifically as related to underlying comorbidities, and the limitations of current literature that failed to account for such differences, we leveraged appropriate statistical methodology to study our research questions. overlap propensity score 21, 22 weighting was performed to address potential confounding in comparing hcw to non-hcw given their baseline differences. the overlap propensity score weighting method was chosen given its benefits of preservation of numbers of individuals in each group and of achieving higher levels of precision in the resulting estimates. this methodology is preferred when the propensity score distributions among the groups are dissimilar and when the propensity scores are clustered near the extremes (i.e., close to zero or one). a propensity score for being a hcw was estimated from a multivariable logistic regression model. for the outcome of being test positive for covid-19, the propensity score logistic regression model included covariates that were found to be associated with a positive covid-19 test outcome in our previous work. 23 for the outcomes of hospital and intensive care unit (icu) admission of covid-19 testpositive patients, the propensity score covariates are those that were found associated with covid-19 hospitalization outcome in our previous work including age, race, ethnicity, gender, smoking history, body mass index, median income, population per housing unit, presenting symptoms (including fever, fatigue, shortness of breath, diarrhea, vomiting), comorbidities (including asthma, hypertension, diabetes, immunosuppressive disease), medications (including immunosuppressive treatment, nonsteroidal anti-inflammatory drugs [nsaids]), and laboratory values (including pre-testing platelets, aspartate aminotransferase, blood urea nitrogen, chloride, and potassium). the overlap propensity score weighting method was then applied where each patient's statistical weight is the probability of that patient being assigned to the opposite group. 21 overlap propensity score weighted logistic regression models were used to investigate associations between hcw status and the probability of testing positive for sars-cov-2, hospital admission for covid-19, and icu admission for covid-19 illness. the results are thus reported as weighted proportions, odds ratios, and 95% confidence intervals. all statistical analyses were performed using r 3.5 and sas version 9.4 (sas institute). p values were 2-sided, with a significance threshold of 0.05. we then used locally weighted regression smoother (loess) to summarize the trend of covid-19 test positivity through the study period for hcw and non-hcw as related to the public health measures instituted at the state level and those specific to the cchs. overall tested cohort characteristics. of the 72,909 individuals tested for covid-19 in the cchs research registry, there were 6145 hcw and 66,764 non-hcw with over 90% of hcw and 75% of non-hcw tested from ohio. there were 9% of hcw who tested positive for covid-19 compared to 6.5% of non-hcw, p < 0.001 (table 1 ). the hcw tested were younger than the non-hcw (median age 39.7 vs. 57.5, p < 0.001) with more females (proportion of males 21.5 vs. 44.9%, p < 0.001), higher proportion of asian and lower proportion of black persons (3.4 vs. 1.0% and 16.2 vs. 18.3%, respectively, p < 0.001), higher proportion identifying as non-hispanic (90.8 vs. 87.6%, p < 0.001), higher median income, and higher proportion of nonsmokers. the neighborhood characteristic of population density as measured per square kilometer was similar for tested hcw vs. non-hcw while the population per housing unit was slightly higher. the hcw were more likely to report an exposure to covid-19 (72.0% vs. 17.0%, p < 0.001) and also to report having a family member with covid-19 (28.3 vs. 14.2%, p 0.005). regarding presenting symptoms, a slightly higher proportion of hcw reported cough (32.0 vs. 29.6%, p 0.001), a lower proportion reported fever (15.0 vs. 19.5%, p < 0.001) or shortness of breath (14.6 vs. 25.7%, p < 0.001), while a higher proportion reported diarrhea (11.9 vs. 9.5%, p < 0.001) and a lower proportion reported vomiting (7.4 vs. 9.7%, p < 0.001). of note, the tested hcw were, in general, healthier than the non-hcw group. the hcw had a lower proportion of several comorbidities including chronic obstructive pulmonary disease(copd)/emphysema, diabetes, hypertension, coronary artery disease, heart failure, cancer, history of transplant, or immunosuppressive disease and were more likely to have received the influenza vaccine (85.9 vs. 45.4%, p < 0.001). the hcw tested had a lower proportion of previous prescriptions for immunosuppressive treatment, nsaids, steroids, carvedilol, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, or melatonin. covid-19 cohort characteristics and outcomes. there were 551 hcw and 4353 non-hcw who tested positive for covid-19 (appendix table 1 ). of those who tested positive for covid-19, a lower proportion of hcw were hospitalized compared to non-hcw (38 or 6.9% hcw vs. 1205 or 27.7% non-hcw) or were admitted to the intensive care unit (10 or 1.8% hcw vs. 470 or 10.8% non-hcw). in the group who tested positive for covid-19, there was a greater proportion of hcw of asian and white race compared to non-hcw (2.9 vs. 0.8% and 61.0 vs 56.4%, respectively); a similar proportion of hcw with a positive covid-19 test had presenting symptoms of cough, fatigue, diarrhea, loss of appetite, and vomiting; and a lower proportion had fever or shortness of breath. lower proportions of hcw testing positive had cop-d/emphysema, diabetes, coronary artery disease, heart failure, cancer, or immunosuppressive disease and were previously prescribed carvedilol, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, or melatonin compared to non-hcw. the neighborhood population characteristics of population density or population per housing unit did not differ for those hcw who tested positive and median income was slightly higher compared to non-hcw. overlap propensity weighting. using the variables in the prediction model for covid-19 test positivity, 23 overlap propensity score weighting (table 2 ) resulted in propensity score weighted proportions of 7.7 vs. 8.9 for non-hcw vs. hcw having a positive test and produced an overlap propensity score weighted odds ratio of 1.17 with a 95% confidence interval (ci) of 0.99-1.38 for a hcw having a positive test compared to a non-hcw (fig. 1a) . then using the variables (fig. 1a) . we then compared characteristics of hcw identified as having positions that required direct contact with patients ("patient facing") and those that did not. there were 5159 hcw with patient-facing positions and 986 hcw in nonpatient-facing roles (appendix table 3 ). the hcw with patient-facing roles were younger (median age 38 vs. 47 years, p < 0.001), with more females (proportion males 20.6 vs. 26.2%, p < 0.001), lower proportion of black race and higher asian race, and with greater proportion reporting exposure to covid-19 (73.7 vs. 62.9%, p < 0.001). the patient-facing hcw had lower proportions presenting with fatigue or shortness of breath and higher proportion with loss of appetite. there were no significant differences in laboratory values upon presentation. the patient-facing hcw had lower proportions of some previously prescribed medications including nsaids, steroids, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and melatonin. the patient-facing hcw group had lower proportions of comorbidities including copd/emphysema, diabetes, hypertension, coronary artery disease, cancer, connective tissue disease, and immunosuppressive disease. applying the overlap propensity score weighting (appendix tables 4 and 5 ; fig. 1b the summary of the trend of sars-cov-2 positive test results in the study period is shown in figure 2 . the overall proportion of positive covid-19 test results decreased during the study period and the trend for hcw and followed that of non-hcw. our analysis of hcw compared to non-hcw who were tested for sars-cov-2 in one health system with 2 geographic locations (ohio, florida), and which controlled for significant differences in baseline characteristics between the hcw and non-hcw groups, showed that the odds of having a positive covid-19 test were not significantly different for hcw compared to non-hcw, and hcw had lower odds of subsequent hospitalization, and without statistically significant differences in icu admission compared to non-hcw once they tested positive. the hcw classified as having patient-facing positions had higher and significant odds of a positive covid-19 test with insignificant differences detected compared to non-patient-facing hcw in outcomes of hospitalization or icu admission. we found a similar proportion of hcw with a positive covid-19 test had presenting symptoms of cough, fatigue, diarrhea, loss of appetite, and vomiting while a lower proportion had fever or shortness of breath. we note that we were not able to capture the symptoms of loss of taste and/or smell and that these symptoms may be common especially with mild cases of covid-19. 24, 25 the overall proportion of covid-19 positive tests in hcw was low and decreased during the study period corresponding with implementation of risk-mitigation measures in our health system such as the recommendations for universal masking and physical distancing but also followed the trend for non-hcw. several of the previous studies of hcw risk for infection during the covid-19 pandemic were limited by their sample sizes, 7-9 lack of generalizability for healthcare systems that have adequate access to ppe, 7-9 methodology relying on self-report, 12 limited ability to adjust for known risk factors of disease susceptibility and progression, [7] [8] [9] [10] 12 and lacking data to investigate the relative effects of dual exposure of hcw to covid-19 in the community versus the workplace. [7] [8] [9] [10] 12 the fact that hcw identified as patient facing had a significantly higher odds for sars-cov-2 test positivity suggests an increased risk of covid-19 infection with work exposure. however, it is important to note in our study that over 70% of the hcw group reported an exposure to covid-19 with 28% reporting exposure to a family member with covid-19. in our study, we were not able to confirm if the patientfacing hcw were working in patient-facing areas during the 14-day period before the test was ordered when exposure could have occurred, or whether the exposure occurred with or without ppe-both in the workplace or in the community, or the relative contribution of initially prioritizing testing availability to hcw with reported exposures. while the risk to hcw attributed to community spread may not be captured in our available data, the reported exposure risk including the higher proportion of hcw vs. non-hcw reporting exposure to a family member with covid-19 suggests a degree of community acquisition of infection. a potential contributing factor to community acquisition is that hcw, particularly patient-facing hcw, are less able to follow stay-athome guidelines or work remotely from home. indeed, while ppe use is associated with decreased risk of infection from coronavirus, 26 a recent report estimated less than 5% risk to hcw inadvertently exposed to patients not known to be sars-cov-2-positive at the time of initial exposure with exposure likely occurring without appropriate ppe 27 suggesting that the work exposure risk may actually be low. however, universal pandemic precautions have been recommended for optimal risk mitigation for hcw. 28 in our analysis of one healthcare system which implemented significant risk-mitigation strategies to prevent the spread of covid-19 infection, and which controlled for significant baseline differences in hcw compared to non-hcw, the odds for sars-cov-2 infection were similar for hcw and non-hcw and hcw had lower odds for covid-19-related hospitalization. the patient-facing hcw had higher odds of sars-cov-2 infection. centers for disease control and prevention clinical characteristics of 80 hospitalized frontline medical workers infected with covid-19 in wuhan, china figure 2 proportion of sars-cov-2 positive results during the study period. cchs = cleveland clinic health system characteristics of health care personnel with covid-19 -united states strong associations and moderate predictive value of early symptoms for sars-cov-2 test positivity among healthcare workers, the netherlands characteristics of deaths amongst health workers in china during the outbreak of covid-19 infection health insurance status and risk factors for poor outcomes with covid-19 among u.s. health care workers: a cross-sectional study characteristics of and important lessons from the coronavirus disease 2019 (covid-19) outbreak in china: summary of a report of 72 314 cases from the chinese center for disease control and prevention covid-19: the daunting experience of health workers in transmission of covid-19 to health care personnel during exposures to a hospitalized patient first experience of covid-19 screening of health-care workers in england masks for prevention of respiratory virus infections, including sars-cov-2, in health care and community settings risk of covid-19 among frontline healthcare workers and the general community: a prospective cohort study association between universal masking in a health care system and sars-cov-2 positivity among health care workers network-based drug repurposing for novel coronavirus 2019-ncov/ sars-cov-2 | cell discovery. accessed extracting and utilizing electronic health data from epic for research research electronic data capture (redcap)-a metadata-driven methodology and workflow process for providing translational research informatics support department of health covid-19 outbreak the state of florida issues covid-19 updates | florida department of health addressing extreme propensity scores via the overlap weights understanding observational treatment comparisons in the setting of coronavirus disease 2019 (covid-19) individualizing risk prediction for positive covid-19 testing: results from 11,672 patients loss of taste and smell as distinguishing symptoms of covid-19 evolution of altered sense of smell or taste in patients with mildly symptomatic covid-19 epidemiology of and risk factors for coronavirus infection in health care workers covid-19 infections among hcws exposed to a patient with a delayed diagnosis of covid-19 universal pandemic precautions-an idea ripe for the times conflict of interest: the authors declare that they do not have a conflict of interest.publisher's note springer nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. key: cord-284640-tl9nmvog authors: tabah, alexis; ramanan, mahesh; laupland, kevin b.; buetti, niccolò; cortegiani, andrea; mellinghoff, johannes; morris, andrew conway; camporota, luigi; zappella, nathalie; elhadi, muhammed; povoa, pedro; amrein, karin; vidal, gabriela; derde, lennie; bassetti, matteo; francois, guy; kai, nathalie s.s.i.y.a.n.; de waele, jan j. title: personal protective equipment and intensive care unit healthcare worker safety in the covid-19 era (ppe-safe): an international survey date: 2020-06-13 journal: j crit care doi: 10.1016/j.jcrc.2020.06.005 sha: doc_id: 284640 cord_uid: tl9nmvog purpose: to survey healthcare workers (hcw) on availability and use of personal protective equipment (ppe) caring for covid-19 patients in the intensive care unit (icu). materials and method: a web-based survey distributed worldwide in april 2020. results: we received 2711 responses from 1797 (67%) physicians, 744 (27%) nurses, and 170 (6%) allied hcw. for routine care, most (1557, 58%) reportedly used ffp2/n95 masks, waterproof long sleeve gowns (1623; 67%), and face shields/visors (1574; 62%). powered air-purifying respirators were used routinely and for intubation only by 184 (7%) and 254 (13%) respondents, respectively. surgical masks were used for routine care by 289 (15%) and 47 (2%) for intubations. at least one piece of standard ppe was unavailable for 1402 (52%), and 817 (30%) reported reusing single-use ppe. ppe was worn for a median of 4 h (iqr 2, 5). adverse effects of ppe were associated with longer shift durations and included heat (1266, 51%), thirst (1174, 47%), pressure areas (1088, 44%), headaches (696, 28%), inability to use the bathroom (661, 27%) and extreme exhaustion (492, 20%). conclusions: hcws reported widespread shortages, frequent reuse of, and adverse effects related to ppe. urgent action by healthcare administrators, policymakers, governments and industry is warranted. the sars-cov-2 virus and the disease it causes (coronavirus disease 2019; covid-19) has created a global public health emergency following its first appearance in december 2019 (1) . as of early june 2020 there had been more than 6.4 million confirmed cases and 385,000 deaths reported worldwide (2). this highly contagious virus poses a significant but largely preventable risk to healthcare workers (hcw) (3) . in some areas, hcw have comprised up to 11 % of all confirmed covid-19 cases with an increasing number of occupationally attributed deaths being reported (4, 5) . use of personal protective equipment (ppe) can markedly reduce the infection risk associated with caring for covid-19 patients (6, 7) . while there is little evidence to which ppe offers the best protection, training in donning and doffing, simulation and face to face instructions are likely beneficial (8) . as a result of adequacy of instruction, availability of fit-testing, and supply limitations (9) , hcw may not be utilizing ppe as per recommended guidelines (6, 10, 11) . reports of ppe scarcity and unavailability are emerging worldwide. hcws report on social media and the general press resorting to reusing ppe or using household and self-made items in place of ppe. while limited evidence exists on the effectiveness of these practices, it has sometimes been done on the advice of their employers or health organisations (12, 13) . pictures of hcws' faces bruised by wearing masks for extended periods have been used to illustrate the extreme work conditions when caring for such patients. while pain, heat stress and fluid loss with using powered air-purifying respirators (papr) were predicted by experimental data (14) , there are no real-life reports of this issue when using ppe that is available to hcws. the objective of this study was to describe the current reported practices, availability, training, confidence in the use and adverse effects due to extended use of ppe by hcws from around the world caring for covid-19 patients who require icu management. a web-based survey was conducted in order to elicit hcw reports surrounding ppe related to the covid-19 pandemic. participation was voluntary and anonymous. this study was approved and granted a waiver of signed individual informed consent by the royal brisbane and women's hospital human research ethics committee (lnr/2020/qrbw/63041), brisbane, australia. the survey target population was all hcw of any discipline or training background or level who are directly involved in the management of covid-19 patients in a critical care setting. a 2-part studyspecific survey was designed (see electronic supplement). in the first part, questions surrounding basic demographic, training experience, and institutional work characteristics were elicited. no specific identifying data (i.e. name, date of birth) was requested the second part comprised of a series of questions regarding the usual practices and availability of ppe, along with perceptions of its adequacy in terms of supply and training in the workplace as well as adverse effects of wearing ppe on the hcw. questions were developed and the survey pre-tested for ease of administration, flow, and content by management committee members and by experienced clinician volunteers. following iterative revisions, the final survey was developed. an english language version was prepared then translated in the french, spanish and italian languages. the survey started with a binary question: if the respondent declared directly caring for covid-19 patients in the icu setting the survey was continued and the response categorized as valid. in the opposite case the survey was terminated, and the response categorized as invalid. the final survey was prepared using the surveymonkey® online platform (svmk inc., san mateo, usa) and posted at https://www.surveymonkey.com/r/ppe-safe. the survey was planned to be open for 2 weeks starting march 30. only the english language version was initially available with the others implemented as of april 7, 2020. duration of the survey was subsequently extended and we report data collected between march 30 and april 20, 2020. subjects were invited to participate through several venues including email invitations using mailing lists of the european society of intensive care medicine, australia and new zealand intensive care society, australian college of critical care nurses, and the european society of clinical microbiology and infectious diseases. in addition, ad hoc emails and advertisements were made via personal networks and social media accounts of management committee members. survey results were exported to and analysed using stata 15.1 (stata corp, college station, usa). means with standard deviations (sd) and medians with interquartile ranges (iqr) were used to describe normally and non-normally distributed continuous variables, respectively. differences in grouped means and medians were tested using the t-test and wilcoxon rank-sum test, respectively. categorical data were compared using the chi-square or fisher exact tests. a p-value less than 0.05 was deemed to represent significance for all comparisons. we performed univariate logistic regression to test the effect of ppe-clad shift duration, modelled as a continuous variable, on adverse effects. we used a separate univariate model for each adverse effect, and for any adverse effect. valid responses were received from 2711of 4879 (56%) individuals who accessed the survey. of which 1797 (67%) were physicians, 744 (27%) were nurses, and 170 (6%) were allied hcw (table 1 and figure e-sup 1). the median age was 41 (iqr, 34-49), 1254 (46%) were female. as detailed in the electronic supplement, respondents worked in 90 different countries, mostly from europe (1666; 61%) followed by asia (437; 16%), and north america (224;8%). most (1585; 58%) respondents worked in a covid-19 dedicated icu, including 281 (10%) in another area re-purposed as a covid-19 icu. one third (924; 34%) of subjects reported working in an icu that contained patients with and without covid-19, and 201 (7%) worked in other areas. as shown in table 1 , several characteristics were different among those working in covid-19 dedicated or repurposed icus as compared to mixed or other icus. in the routine care of patients with covid-19 most respondents reported use of ffp2/n95 masks (1557; 58%), surgical masks were reportedly used for routine care in 289 (15%) cases but infrequently (47, 2%) for intubations. waterproof long sleeve gowns (1623; 67%), and face j o u r n a l p r e -p r o o f shields/visor (1574; 62%). use of papr was infrequent with routine care (184; 7%) or intubation (254, 13%). their use was more frequent in asian and north american countries compared with oceania and europe but was not associated with the type of icu, it's capacity or current workload. variations between countries were wide and shown in the electronic supplementary tables 3. a comparison of ppe usage between professions is shown in the electronic supplementary table 2 . comparisons should be interpreted with caution as due to the nature of the survey it is unknown if differences between respondents may is due to their institution or profession. a comparison of the ppe used in routine care and for intubation among the respondents is shown in figure 1 . six hundred and twenty-eight (23%) subjects reported use of different mask for intubation compared to routine care. the corresponding numbers for gown and eye protection are 284 (12%) and 495 (20%). (table 2) ppe availability more than half of respondents (1402, 52%) reported at least one piece of the standard ppe as not available, and 817 (30%) reported that at least a piece of single-use ppe was being reused or washed as a result of shortages ( table 2 ). the distribution of ppe that was reportedly not available or being reused is shown in table 2 . overall few respondents indicated that no additional ppe should be provided. among the 1184 (44%) respondents that detailed additional need, this was most commonly hazmat suits and paprs. homemade solutions to ppe shortages included 3d printed face shields (529, 20%), homemade gowns (163, 5%), and homemade masks (145, 5%). there were wide variations between countries, with some reporting up to 19% of some items missing and others up to 39% being reused (tables electronic supplement 2). most of the respondents (2245, 83%) reported that they had formal training in the use of ppe. that included training at commencement in the institution (336, 13%) and within the last 2 months due to the covid-19 pandemic (1509, 60%). most reported they would benefit from additional training, this included simulation (1224, 49%) or demonstration by infection control specialists (478, 19%), and didactic teaching (220, 9%). less than half reported having formalized mask fit testing at any time (1243, 49%). a two-person technique was reportedly used for donning (193, 8%), doffing (159, 6%), or both (643, 26%), sometimes (881, 35%) but never in almost one-quarter (639, 25%) of respondents. there was a strong association between reporting never use of a 2 persons technique and never receiving ppe training, fit testing, and low confidence in using recommended ppe (p<0.001 for all comparisons) almost half (1211, 45%) reported being very or confident with their technique in using the available ppe and 138 (5%) were not confident at all. confidence in the adequacy of protection was reported by 1187 (44%), while 376 (14%) were not confident at all. this was similar for doctors, nurses and allied health (p=0.93). there was a strong association between confidence in protection and the absence of ppe shortage and confidence in technique (p<0.001 for both comparisons). the median duration of a shift while wearing ppe without the ability to take a break (ppe-shift) as 4 hours (iqr 2, 5 hours). this was similar for nurses (median 4, iqr 2, 6 hours) and doctors (median 4, iqr 3,5 hours). adverse effects were reported by 80%, including heat (1266, 51%), thirst (1174, 47%), pressure areas (1088, 44%), headaches (696, 28%), inability to use the bathroom (661, 27%) and extreme exhaustion (4924, 20%) ( table 3) . they were all associated with longer duration of shifts wearing ppe (table 4 ). this survey provides a snapshot of the reported availability, perceived adequacy of training and provided protection, adverse effects and usage of ppe among hcw managing covid-19 patients in critical care environments from across the globe. it is important to note that these responses are likely influenced by how burdened hcw are, the safety culture, and the baseline resources in their institutions. while these data do not prove adequacy or inadequacy of ppe per se, they do lend important insights into what hcw are experiencing in this novel pandemic situation. it is important to recognize that information on human-to-human covid-19 transmission is still emerging. while respiratory droplets are considered as the main route of transmission, airborne transmission resulting from aerosol-generating procedures likely is a mode (15) . surface contamination with transmission using contact means is another route of infection transfer (16) . recommendations for ppe vary significantly both between and within countries. as an example, airborne precautions are recommended only for high-risk procedures in some countries whereas this is routinely in others (6, 10, 11, 17) . furthermore, shortages of ppe equipment has led to practices to reduce, reuse, or substitute lesser or non-approved products in an attempt to address inadequate supply of ppe (18) . variability in knowledge, training and technique, such as the formal fit testing of respirators or the use of a 2 persons technique for donning and doffing ppe are correlated with confidence and likely impact safety of hcws managing icu patients infected with covid-19. these factors contribute to a sense of uncertainty and lack of confidence in a safe workplace among hcw (9, 19) . access to appropriate ppe was the first of 8 sources of anxiety in a group of hcws interviewing during the first week of the pandemic (20) . this is likely further exacerbated by frequent changes in guidelines and public health messages. those may be secondary to epidemiological changes, the rapidly accumulating knowledge but also by the scarcity of the resource, further increasing anxiety and distrust from hcws. the shortages and concerns surrounding provision of adequate ppe represents a major issue from a supply chain perspective. this further raises serious concerns about equity and justice related to provision for those most in need. at local levels, reports of ppe being stolen from healthcare institutions, misappropriated, or hoarded have occurred such that this equipment may not be available to those at highest risk (18) . at subnational and national levels this has also become a concern as bidding wars and re-direction of orders has occurred. recent examples of countries threatening to block export shipments of ppe to other countries has further exacerbated concerns by hcw around access to appropriate ppe. while it is likely that innovative approaches and ramp-up of domestic manufacturing processes may help to meet demand, it is a serious risk for low income countries who may ultimately suffer the greatest adverse effects of lack of ppe. confirming social media and widely distributed photos of hcws bruised faces, most respondents have reported adverse effects from ppe. this question the safety of currently available ppe when it is worn for an extended duration. most of the available ppe was designed and manufactured for single-use and brief duration of use. these findings call for urgent design and manufacture of ppe j o u r n a l p r e -p r o o f that can be safely worn and remains effective for extended durations. it also reinforces the need for recruitment of an increased health care workforce. this would allow for surge capacity whilst minimizing harm to frontline staff. there are some limitations of this study that must be noted. first, it is a voluntary survey and responses reflect opinions and perceptions alone. they may not necessarily reflect actual practices as these are not confirmed through audit. second, we did not use a systematic sampling strategy but rather made the survey broadly available and accordingly there is no denominator to establish a response rate. therefore, our results may reflect a small portion and potentially biased reflection of the true opinions of all hcw. by using scientific society mailing lists we may have skewed the sampling towards the geographical location of their members. however, we elected to pursue this study approach in order to obtain a contemporary view. given the time frame and rapid changes related to this pandemic, we therefore elected to pursue this study without subsequent formalized sampling strategy. this allowed the identification of trends in reported use of ppe rather than real time data. third, the study has an over-representation by physicians which may underestimate the burden of adverse effects caused by ppe. fourth, there is an underrepresentation of low-and middle-income countries, which may have skewed the results. finally, we only offered the survey in english, french, spanish and italian. this may have been a barrier for some hcw to participate and may have resulted in a selection of respondents that may be different had we included options for other languages. in summary this survey study provides a snapshot of reported ppe practices availability, and confidence in adequacy to provide protection among hcws at the frontlines of the covid-19 pandemic. respondents report widespread shortages and reuse of single-use ppe items. half of the respondents had never had fit-testing of masks. adverse effects from ppe usage frequently reported and mostly associated with ppe-clad shift duration. urgent action by healthcare administrators, policymakers, governments and industry is warranted to address these issues. this study was endorsed by, and communications were sent to the members of: a novel coronavirus from patients with pneumonia in china association of public health interventions with the epidemiology of the covid-19 outbreak in wuhan coronavirus disease 2019 (covid-19): situation report doctors, nurses, porters, volunteers: the uk health workers who have died from covid-19 2020 surviving sepsis campaign: guidelines on the management of critically ill adults with coronavirus disease 2019 (covid-19). intensive care medicine personal protective equipment during the covid-19 pandemic -a narrative review personal protective equipment for preventing highly infectious diseases due to exposure to contaminated body fluids in healthcare staff covid-19: the crisis of personal protective equipment in the us infection prevention and control during health care when covid-19 is suspected: interim guidance covid-19 personal protective equipment (ppe) considerations for acute personal protective equipment (ppe) shortages 2020 recommended guidance for extended use and limited reuse of n95 filtering facepiece respirators in healthcare settings limiting factors for wearing personal protective equipment (ppe) in a health care environment evaluated in a randomised study aerosol and surface distribution of severe acute respiratory syndrome coronavirus 2 in hospital wards aerosol and surface stability of sars-cov-2 as compared with sars-cov-1 practical recommendations for critical care and anesthesiology teams caring for novel coronavirus (2019-ncov) patients critical supply shortages -the need for ventilators and personal protective equipment during the covid-19 pandemic protect our healthcare workers understanding and addressing sources of anxiety among health care professionals during the covid-19 pandemic n95/ffp2 maks 1557, (57%) 127, (8%) 267, (17%) ffp3 mask 649 face shield or visor 1574, (58%) 131, (8%) 820, (52%) cover 1636, (60%) 43, (3%) 41, (3%) balaclava reported as missing denoted ppe that would normally be used but is not available. none reported denotes respondents that did not report using any equipment in that category of ppe. washed or reused denotes single use ppe that is washed or reused due to stock or availability issues. papr shown as mask and head protection as includes a hood and shown as n/a for reuse as they are reusable by design extreme exhaustion 77, (12%) 187, (20%) 116, (27%) 32, (31%) inability to use the bathroom 61, (9%) 261, (28%) 176, (41%) 47, (45%) headaches 118, (18%) 297, (31%) 137, (32%) 36, (35%) thirst 216 footer: ppe-shift duration denotes the amount of time in hours that the hcw is wearing ppe without the ability to take a break j o u r n a l p r e -p r o o f key: cord-333460-4ui8i9u5 authors: li, qing; chen, jinglong; xu, gang; zhao, jun; yu, xiaoqi; wang, shuangyan; liu, lei; liu, feng title: the psychological health status of healthcare workers during the covid-19 outbreak: a cross-sectional survey study in guangdong, china date: 2020-09-18 journal: front public health doi: 10.3389/fpubh.2020.562885 sha: doc_id: 333460 cord_uid: 4ui8i9u5 background: the sudden outbreak of covid-19 has caused mental stress on healthcare workers (hcw). this study aimed to assess their psychological health status at the peak of covid-19 and to identify some coping strategies. methods: a cross-sectional survey study was conducted during the outbreak of covid-19. the survey was completed by 908/924 hcw (response rate 98.27%) in government-designated hospitals in guangdong, china. a quality of life (qol) scale, the zung self-rating anxiety scale (sas), and the zung self-rating depression scale (sds) were used to evaluate their psychological status. logistic regression models were used to identify the occupational factors related to anxiety or depression. results: a total of 221 (24.34%) respondents had varying levels of anxiety, and 299 (32.93%) of them had depression. the mean sas (42.9) and sds (47.8) scores of hcw indicated that they were in the normal range for both anxiety and depression. contact with covid-19 cases or suspected cases, worry about suffering from covid-19, worry about their family, and dismission during the covid-19 period were significant work-related contributing factors to the psychological health problems of hcw (all p<0.01). conclusions: the overall psychological health status of hcw in guangdong, china, during the outbreak of covid-19 was not overly poor. updating and strengthening training in disease information, the provision of adequate medical supplies, and care about the life and health of medical staff and their family members may reduce their mental stress. in december 2019, the outbreak of pneumonia caused by the 2019 novel coronavirus (2019-ncov) in wuhan, hubei province, china (1, 2) , was quickly spread by the largest human migration in the world, the spring festival travel rush. by the time of this submission, it had become a serious infectious disease that has spread throughout the world. the world health organization (who) named the infection covid-19 in february 2020. in china, provinces successfully began the first-level response to major public health emergencies on january 23, 2020. guangdong, where the author is located, is one of the most populous provinces in china due to its hyper active economy and booming industry that attracts migrant workers. it is also the province with the largest number of cases after hubei reported during our study period, and huge migration may bring serious outbreaks. previous studies have shown that doctors, nurses, and other staff in hospitals suffer from psychological problems during an epidemic of an infectious disease. during the outbreaks of the 2003 severe acute respiratory syndrome (sars) and 2015 middle east respiratory syndrome (mers), psychological problems, including anxiety, depression, and sleep disorders, were very common in medical workers in taiwan, hong kong, singapore, korea, and canada (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) . similar to sars and mers, front-line healthcare workers (hcw) may be in direct contact with and have to care for patients and suspected cases of covid-19; they are therefore at a particularly high risk of infection. in the battle against covid-19, more than 3,000 doctors and nurses have been infected, and a dozen have died. hcw also face pressure from overwork, lack of supplies, negative emotions of patients, and concerns about their families. these factors may cause many psychological stress (14, 15) . to date, there have been few known systematic studies targeting this topic. the aim of our study was to assess the psychological status of hcw in guangdong province, china, and to identify coping strategies during the outbreak of covid-19. this study was a cross-sectional survey study. it was approved by the ethics committee of the guangzhou first people's hospital (k-2020-055-01). considering the high infectivity of covid-19, the popularity of wechat in china, and the feasibility of electronic questionnaires, a professional online questionnaire platform powered by www.wjx.cn was used in answering the paperless survey. we started the survey on february 3 for the medical institutions that resumed their work after the spring festival. at that time, 10 days had passed since the chinese government officially declared a state of emergency on january 23. the research objects of this study were doctors, nurses, and other staff in the government-designated hospitals in guangdong including guangzhou first people's hospital, guangzhou eighth people's hospital (infectious disease hospital), and 10 other hospitals. non-medical staff were defined as a control group. persons with previous mental illness were excluded. february 24 was used as the cut-off point because the major public health emergency was adjusted to the second level on that day. the study was conducted at the peak of the covid-19 outbreak. all respondents completed the survey anonymously. they were required to complete questionnaires on quality of life (qol) and psychological comorbidities. each item had to be answered before it could be submitted. a mobile internet protocol address was limited to only one response to avoid duplication. a professional psychologist participated in the whole process of this research and assisted in evaluating the psychological state of the respondents. the results were used for analysis. the questionnaire consisted of three sections and started with informed consent. all participants provided informed consent before proceeding with the subsequent investigations. the first section recorded the participants' sociodemographic variables and personal information, including age, gender, marital status, education, occupation, working hours, financial status, income satisfaction, and essential sleep conditions. we defined the front-line doctors and nurses in the fever clinic, emergency department, and intensive care unit as high-risk medical staff, while others were low risk. the second section collected information about covid-19. because covid-19 is a new disease, we could not find a validated instrument for it. we referred to studies on sars and mers and then designed several items, such as exposure to covid-19, training for the disease, and stigma. two established methods were used in the third section. anxiety and depression were the most prevalent mental illnesses. symptoms of anxiety and depression in the past week were assessed by the zung self-rating anxiety scale (sas) (16) and the zung self-rating depression scale (sds) (17) , which have been well-validated (18) . both sas and sds use 20-items likert scales with four potential answers ranging from one (little of the time) to four (most of the time). the raw scores are transformed into index scores (range 25-100) (sas index score: < 50 = normal, 50-59 = mild anxiety, 60-69 = moderate anxiety, ≥70 = severe anxiety; sds index score: < 53 = normal, 53-62 = mild depression, 63-72 = moderate depression, ≥73 = severe depression). descriptive statistics were performed on demographic factors, health factors, economic factors, work factors, and sas and sds scores. differences in sas and sds scores for occupation were accessed with analysis of variance (anova). then we compared the morbidities of anxiety and depression between two different occupational groups using the chi-squared test. multivariate logistic regression models (unadjusted and adjusted) were used to examine the relationships between covid-19 work-related factors and anxiety and depression. we defined cases with anxiety when the sas score was over 50 and defined cases with depression when the sds score was over 53. in all models, we separately included the following factors: occupation, working years, contact with covid-19 cases, worry about suffering from covid-19, worry about their family suffering from covid-19, worry about stigma due to covid-19-related jobs, and dismission intention during the covid-19 period. for each model, we adjusted for age, gender, education, marital status, monthly income, and history of basic illness. we defined statistical significance as p < 0.05 for a two-tailed test, and all statistical analyses were conducted using r v3.42 (r foundation for statistical computing, vienna, austria). a total of 924 surveys of hcw were collected, 908 (response rate 98.27%) of which were completed correctly. sixteen respondents (1.73%) were excluded due to significant data errors in the age, height, and weight items. and 369 questionnaires of the controls were completed at the same time. the sociodemographic characteristics and other information for covid-19 of healthcare workers and controls are given in table 1 . the results showed that there was no significant difference between hcw and the controls in terms of age, gender, marital status, and history of basic illness. in total, 67.7% of the hcw respondents had direct contact with covid-19 patients or suspected cases at work. a total of 25.88 and 41.08% of the hcw respondents worried about themselves or their family members being infected by covid-19, respectively. only 6 (0.66%) hcw respondents had feelings of social discrimination. a total of 16.19% of the hcw respondents showed the intention to take leave or resign from their job. compared with the controls, hcw has a significantly higher morbidity of both anxiety and depression. among them, 221 (24.34%) hcw participants had varying levels of anxiety with a mean sas score of 42.9, and 299 (32.93%) of them had depression. the mean sds score was 47.8. sas and sds scores in different occupational groups and morbidity of anxiety and depression are shown in table 2 . the chi-squared test showed that the morbidity of anxiety was increased significantly in clinicians at high risk than at low risk (χ 2 = 8.895, df = 1, p = 0.003). there was an increase in morbidity of both anxiety and depression in nurses at high risk compared with nurses at low risk (anxiety: the determining factors of anxiety and depression are shown in tables 3, 4. in table 3 previous studies have shown that 23.9-68.8% of hcw suffered from mental health problems in china due to the high workload, promotion pressure, deteriorating doctor-patient relationships, medical disputes, and even violence (19) (20) (21) (22) . on this basis, the outbreak of covid-19 undoubtedly increased the psychological pressure of hcw, who were the soldiers in this battle. our study found that the anxiety and depression rates of hcw during the peak of the covid-19 epidemic were 24.34 and 32.93%, respectively. staff in low risk positions had a lower rate of psychological problems than doctors and nurses who worked in positions with a high risk of covid-19 exposure, such as fever clinics, emergency departments, and intensive care units, especially nurses. compared with doctors, nurses had more opportunities to have contact with cases, which increased the risk of infection. however, surprisingly, the mean scores of the sas (42.9) and sds (47.8) of hcw indicated that they were in the normal range for both anxiety and depression, which seemed to differ from the results of previous studies on sars and mers (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) . we performed stratification analysis by occupational exposure risk or patient contact history but obtained similar results. reviewing the past few months in china during covid-19, whether it was wuhan in the peak of the epidemic, or in harbin, heilongjiang province, where the hospital infection outbreak happened recently, covid-19 mainly attacked theoretically low risk hcw (medical staff in departments for ophthalmology, surgery, neurology, and caregivers) (23) . critical illness medical staff were also in this category. in harbin, epidemiological studies further confirmed that the lack of sufficient vigilance and personal protection in hcw was the main reason for the hospital infection. this could suggest that there is no real low risk area during covid-19. our study was conducted after the notification of high infection in low risk departments in wuhan. guangdong was the most seriously affected area except hubei at that time. but the anxiety and depression of hcw in low risk departments were still significantly lower than those in high risk departments. this situation was most likely due to insufficient vigilance. anxiety helps us anticipate and assess potential danger in ambiguous situations (24, 25) . combined with the results of our study, it is possible that our awareness of disease prevention and self-protection can be strengthened by some psychological pressure during covid-19. on the contrary, it may increase the chance of infection due to lack of tension or negligence of the disease. this is the population that should be concerned and their knowledge of disease and personal protection should be enhanced. our aim was to identify the determinative factors of the impact of covid-19 on hcw's psychological status. a review of previous literature suggests that many factors can also affect the mental health of hcw in non-epidemic situations (19) (20) (21) (22) . further adjusted logistic regression showed that there was no significant correlation between the exposure risk and occupation, working years, and stigma and the psychological status of hcw during the outbreak of covid-19. however, concerns about selfinfection and family health were statistical factors that were all positively related to both anxiety and depression according to the sas and sds scores. we will attempt to determine reasons for this result. similar to sars and mers, covid-19 can be spread by respiratory droplets and direct contact, with urine, stool, and saliva being potential routes (26) (27) (28) (29) . although an early study evaluated its r0 = 2.2 (1), other studies found the average r0 to be 3.28, even reaching 6.47 (26) (27) (28) (29) . compared with sars (r0 = 3.6), the contagious power of covid-19 is much higher (27) . hcw who face such a highly contagious disease with an incubation period, especially nurses at high risk (40.83%, 69/169), show serious concern about their possibility of infection. a total of 41.12% of the respondents worried about their families due to both the lack of care and the high risk of infection caused by the hcw themselves. however, the statistical results showed that the experience of contact with patients or suspected cases was a positive factor for both anxiety and depression. our investigation showed that all the respondents, even administrative staff, received different levels of medical knowledge and protection training about this infectious disease. apart from the brief panic at the beginning, 99.01% of them believed that the available protective measures were adequate at this moment. this may be due to the improvement of china's disease control system and the development of awareness of infectious disease prevention and control after the experience of sars (30) . the more people are prepared for covid-19, the more confident they can be. during sars and mers, 20-49% of hcw experienced social stigmatization because of their jobs (3, 5, 7, 10, 12) . however, in our study, it seemed that hcw did not worry about stigma (99.34%). this may be related to the development of social media, information disclosure, and the government's positive publicity. accurate and timely covid-19 information was provided to the public to reduce uncertainty and minimize stigmatization of hcw. this suggestion was mentioned in ya mei bai's article and now seems to be effective (3) , and hcw are hailed as heroes in harm's way (31). the public has shown more respect for medical staff, which may reduce the stress of hcw. we found that 16.19% of the respondents, mainly caregivers (66.03%, 70/106), had the intention to resign or take leave, while only a few doctors and nurses had this intention. this was a statistically significant factor associated with anxiety among hcw. among the caregivers, 91.51% were married females. this has been seen as an escape in some studies (3, 5, 11) . this may be due to a lower education level (77.35% did not receive a college education) and family identity as a mother, which has caused a shortage of caregivers in many hospitals. a similar conclusion was mentioned by chenyu zhou in her research on chinese medical staff (20) . in addition, our investigation showed that 58.92% of hcw worked more than 8 h a day, 25.33% of them were dissatisfied with their current income, and 23.12% of them had sleeping problems and needed hypnotics. previous studies have shown that these factors were related to the mental health of medical staff in usual jobs. this may be a long-term problem rather than a current one that is specific to the covid-19 epidemic. after the guideline of psychological crisis intervention for 2019-ncov pneumonia was released by the national health commission of china on january 27, it seemed that some measures had been taken (32, 33) . our study finds that there was some effect. the psychological health of hcw was better than expected. the limitations of our study are as follows. firstly, the study was completed on mobile devices, and the sampling was voluntary. therefore, the possibility of selection bias should be considered. secondly, we could not cover all potential risk factors in this investigation. thirdly, the objects of this study were hcw in guangdong province, and this sample cannot represent the mental status of hcw in hubei, the center of the epidemic, who might suffer from more serious psychological problems. although some hcw in guangdong, china, had psychological problems during the outbreak of covid-19 especially the firstline doctors and nurses, the findings of the present study indicated that their overall psychological health status was not too poor. it is possible that our awareness of disease prevention and self-protection can be strengthened by psychological pressure. updating and strengthening training in disease information, providing adequate medical supplies, and caring about the life and health of medical staff and their family members may reduce their mental stress, ensure their working ability, and reduce the risk of treatment for patients. currently, covid-19 has become a global pandemic. perhaps 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workers wang yi delivers a speech at the 56th munich security conference the guideline of psychological crisis intervention for 2019-ncov pneumonia. national health commission of china (chinese) the studies involving human participants were reviewed and approved by the ethics committee of the guangzhou first people's hospital (k-2020-055-01). written informed consent for participation was not required for this study in accordance with the national legislation and the institutional requirements. all authors have read through the manuscript and approve for submission. as the corresponding author, i have had full access to all aspects of the research and writing process, and i assume final responsibility for the contents of the paper. the authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.copyright © 2020 li, chen, xu, zhao, yu, wang, liu and liu. this is an open-access article distributed under the terms of the creative commons attribution license (cc by). the use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. no use, distribution or reproduction is permitted which does not comply with these terms. key: cord-301299-flb5wwzg authors: garcía, inés suárez; lópez, maría josé martínez de aramayona; vicente, alberto sáez; abascal, paloma lobo title: sars-cov-2 infection among healthcare workers in a hospital in madrid, spain date: 2020-07-21 journal: j hosp infect doi: 10.1016/j.jhin.2020.07.020 sha: doc_id: 301299 cord_uid: flb5wwzg aim: the aim of this study was to describe the epidemiological and clinical characteristics of covid-19 among healthcare workers (hcws) between february 24(th) to april 30(th), 2020 in a hospital in madrid, spain. methods: we designed a retrospective cohort study. cumulative covid-19 incidence was calculated for all hcws and categorized according to presumed level of covid-19 exposure (high, medium and low). results: among 1,911 hcw, 213 (11.1%) had covid-19 during the study period. cases increased gradually from march 8(th), peaking in march 17(th) and declining thereafter. the peak of cases among hcws was reached 14 days before the peak in admitted covid-19 cases in the hospital. there were no significant differences in the proportion of covid-19 cases according to level of occupational exposure (p=0.123). there were 5 departments and 2 professions in which more than 20% of the workers had confirmed covid-19. we identified temporal clusters in three of these departments and one profession, with most of the cases occurring over a period of less than 5 days. the prevalence of comorbidities was low and 91.5% of patients had mild or moderate symptoms. eleven patients were admitted to the hospital and 1 patient needed intensive care. none of the patients died. the median time of sick leave was 20 (iqr: 15 – 26) days. conclusions: our results suggest that hcw-to-hcw transmission accounted for part of the cases. in spite of a low prevalence of comorbidities and a mild clinical course in most cases, covid-19 caused long periods of sick leave. the virus sars-cov-2 is the causal agent of the acute respiratory tract infection known as covid-19 (1) . it is estimated that by may 25th 2020, covid-19 had caused 5,304,772 infections and 342,029 deaths(2). the first covid-19 case was declared in spain in january 31st, 2020 (3) and since then, spain has been one of the most affected countries by the pandemic (2) . healthcare workers (hcws) are especially vulnerable to infection by sars-cov-2. in the first published series of 138 patients from wuhan, china, 29% of the cases were hcws(1). the proportion of hcws was much lower (3.8%) in a later case series from china including 72,314 covid-19 cases (4) . in spain, 22% of all the covid-19 cases have been among hcws (5) , and in italy, 20% of responding hcws were infected (6) . very few studies have focused on sars-cov-2 infection among hcws. moreover, the scarce data available to date have focused on the proportion of hcws infected but have not sufficiently described epidemiological and clinical characteristics of the affected workers. there are important implications of covid-19 among hcws. firstly, there are consequences for their health: in the previously mentioned series from china, 14.8% of the cases among hcws were classified as severe or critical and 5 of the patients died (4) . secondly, infected hcws could also transmit the infection to vulnerable patients if they are not properly and timeously isolated. thirdly, high rates of infection among hcws could cause problems due to understaffing in the health system. lastly, the workers may transmit the infection to close family contacts (7) , other hcw (8) , and the community. due to the important implications of covid-19 among hcws, and the lack of detailed information published about this issue, it is important to better characterize its epidemiology and clinical characteristics in order to inform decision-makers on appropriate prevention and management strategies. therefore, we designed a retrospective cohort study whose aim was to describe the epidemiological and clinical characteristics of sars-cov-2 infection among hcws in a hospital in madrid, spain. the study was performed in hospital universitario infanta sofía, a public tertiary hospital in madrid, spain. all hcws that were working in the hospital between february 24 th to april 30 th 2020 were included. workers from the laboratory, radiology department, security services, maintenance services, kitchen facilities, cleaning workers and porters were also excluded as they are contracted by external companies and are not employed by the hospital. variables and data collection all data were gathered retrospectively. the number of hcws according to their profession and department for the study period was obtained from the human resources department. data for covid-19 cases were extracted from the clinical records of the occupational health department and recorded in an anonymized database. during the study period, hcws experiencing symptoms consistent with probable covid-19 were instructed to present at the occupational health outpatient clinic, where they were managed according to the hospital protocol: a nasopharyngeal swab was collected and analysed with polymerase chain reaction (pcr) for sars-cov-2. for symptomatic hcws with negative pcr, this test was repeated after 48-72 hours if symptoms persisted. according to the hospital protocol, hcws with positive sars-cov-2 pcr remained on sick leave until a negative follow-up pcr was obtained. follow-up pcrs among patients with a previous positive pcr were obtained between day 2 and 5 after symptom resolution and repeated thereafter until a negative pcr result was obtained. workers were allowed to return to work when they fulfilled two criteria: symptoms had resolved, and they had a negative follow-up pcr. a case of covid-19 was defined as any hcw presenting to the occupational health outpatient clinic with symptoms consistent with covid-19 and with positive sars-cov-2 pcr. the date of the case was defined as the date of presentation to the occupational health outpatient clinic. the following variables were obtained from the clinical records: age, sex, profession (head of department [i.e., a physician in charge of a medical or surgical department], physician, nurse supervisor, nurse/auxiliary nurse, other), department, date of presentation at the outpatient clinic, date of symptom onset, duration of sick leave, admission to hospital, presence of comorbidities (arterial hypertension, diabetes mellitus, current tobacco consumption, cardiovascular disease, and chronic obstructive bronchopulmonary disease or asthma). nine patients had no information on the day of symptom onset: for these patients, the date of symptom onset was assumed to be the date of presentation to the outpatient clinic. clinical course was divided in the following categories: mild symptoms (including myalgia, ageusia, anosmia, headache, sore throat, cough, or temperature <38 o c, plus no need to stay in bed), moderate symptoms (including fever ≥38 o c, or need to stay in bed, with or without any of the mild symptoms), and unilateral or bilateral infiltrates in chest x-ray. hcws were stratified in three categories according to their presumed level of occupational exposure to covid-19 cases: high risk (hcws with usual contact with covid-19 patients: accident and emergency, internal medicine, intensive care, and pneumology departments), moderate risk (hcws with occasional contact with covid-19 patients: other medical and surgical departments not included in the high or low risk groups) and low risk (including administrative workers, social workers, hospital management, and pharmacy, pathology, and preventive medicine departments). for nurses working in the hospital wards and haemodialysis unit, the department was not available and therefore they were included in a separate category for the purpose of risk of occupational exposure. in addition to these variables, information was collected about the training in covid-19 prevention, and use of personal protection equipment (ppe,) in the hospital during the study period. total numbers of notified covid-19 confirmed by pcr were obtained from the madrid autonomous region website (9) . statistical analysis covid-19 cumulative incidence during the study period was calculated for all hcw, stratified by presumed level of occupational exposure, and stratified by department and profession. for departments and professions with more than 10 hcws, of which more than 20% were diagnosed with covid-19, date of presentation was analysed in detail to detect possible transmission clusters. descriptive analyses were carried out using frequency distributions or median and interquartile range (iqr), as appropriate. the proportions of hcw acquiring covid-19 among the three categories according to risk of occupational exposure were compared with χ 2 test. statistical analyses were carried out with stata version 13.0 (stata corporation, college station, tx, usa). the study was approved by the ethics committee of hospital universitario "la paz" (pi-4133). informed consent was not required. by april 30 th , 2020, there were 1,911 hcws in our hospital that fulfilled inclusion criteria. among these, 652 presented to the occupational health outpatient clinic with symptoms consistent with covid-19 and were tested with at least one pcr during the study period. a total of 213 workers, which account for 11.1% of all hcws included, had microbiological confirmation of covid-19. median age was 42 (iqr: 34-52) years, and 171 cases (80.3%) were women. figures 1a and 1b show the number of confirmed cases among hcws per day, along with the number of patients admitted in the hospital with covid-19 (figure 1a) and the total number of cases notified in the madrid autonomous region (figure 1b) during the study period. the first case among hcws was diagnosed in march 8 th and cases increased gradually, reaching a peak in march 17 th and declining thereafter. the peak of cases among hcw was reached 14 days before the peak in admitted covid-19 cases in the hospital, which occurred on march 31 st (figure 1a), and 9 days before the peak in the notified cases in the madrid autonomous region, which occurred in march 26 th (figure 1b). as expected, cases among hcws very rarely presented during weekends. the median delay between the date of symptom onset and the date of presentation to the outpatient clinic was 2 (iqr: 1 -5) days. the first date of symptom onset was february 17 th and then increased gradually, reaching a peak on march 16 th and gradually declining thereafter. the proportion of cases among hcws according to level of occupational exposure is shown in table i. there were no significant differences in the proportion of covid-19 cases according to level of occupational exposure (high, medium, or low) (p=0.123). there were 5 departments of more than 10 hcws in which more than 20% of the workers had confirmed covid-19: dermatology ( the proportion of cases according to profession are shown in table ii. there were 2 professions in which more than 20% of the workers had confirmed covid-19: medical heads of department (23.1% with covid-19) and nurse supervisors (37.5%). the number of cases according to date of presentation for the departments and professions in which more than 20% of the hcws had covid-19 are shown in figures 2a and 2b, respectively. the cases in the oncology, dermatology and neurology departments seemed to be clustered in time, with all cases presenting in a period of 3 and 4 days in the oncology and dermatology departments, and 4 out of 5 cases presenting in a period of 5 days in the neurology department. according to work category, there also seemed to be a temporal cluster among heads of department, with 8 out 9 cases presenting over a period of 3 days (figures 2a and 2b ). regarding comorbidities, 10 workers (4.75%) had arterial hypertension, 9 (4.2%) had asthma or chronic obstructive bronchopulmonary disease, 7 (3.3%) were active smokers, 4 (1.9%) had cardiovascular disease, and 1 worker had diabetes mellitus. regarding the clinical course, 144 (67.6%) had mild symptoms, 51 (23.9%) had moderate symptoms, 7 (3.3%) had unilateral lung infiltrates in chest x-ray, and 11 (5.2%) had bilateral lung infiltrates. in addition, 2 patients with unilateral lung infiltrates also had thromboembolic disease: 1 patient had deep venous thrombosis and the other had pulmonary embolism. the majority of cases were managed in their home, but 11 cases (5.2%) needed admission to the hospital for a median of 4 (iqr: 4 -10) days. one of the patients with bilateral pneumonia needed icu admission and orotracheal intubation because of severe respiratory failure. none of the patients died. among the 213 workers, 25 were still on sick leave at the end of the study period. the median time of sick leave among the 188 hcws who had returned to work was 20 (iqr: 15 -26) days. after symptom resolution, the median number of pcrs performed per hcw was 1 (iqr: 1-2), and the median time to obtain a negative pcr result (and therefore to allow the hcw to return to work) was 5 days (iqr: 1-7). training in infection control practices and use of ppe was provided by the occupational health department from february 20 th to march 13 th for the intensive care unit, hospitalization wards, surgical rooms, daycare hospital, obstetric ward, nurse supervisors, and the internal medicine, anaesthesia, general surgery and emergency departments. in addition one training session was provided in the pharmacy department on april 22 nd . there were a total of 23 training sessions involving a total of 298 (15.6%) hcws. this study has analysed the epidemiology of sars-cov-2 infection among hcws in a public hospital in spain during the height of the covid-19 epidemic. we found that 11.1% of the hcw had microbiologically confirmed covid-19. the peak of cases preceded the peak of admitted patients with covid-19, with a lag of 2 weeks. the risk of covid-19 did not differ significantly among three groups with different levels of occupational exposure to covid-19 patients, and a few clusters were detected in specific departments and professions: these facts suggest that a considerable proportion of the transmissions occurred from hcw-to-hcw, rather than from patient-to-hcw. infected workers had low prevalence of comorbidities and the clinical course was mild in most cases; in spite of this, covid-19 caused long periods of sick leave. the sources of hcw infection include patients with covid-19, other hcws, and the community. during the covid-19 pandemic several reports have identified factors increasing the risk of patient-to-hcw exposure, mainly excessive workload(10), shortage of personal protection equipment (ppe), lack of training in infection control measures, or use of ppe that does not fulfil safety requirements (11, 12) . also, hcws can become infected outside their workplace if there is ongoing transmission in the community(13) (community-to-hcw). however, it has been pointed out that there is potential for transmission between hcw (hcwto-hcw), with potential occasions such as clinical meetings, clinical handovers, lunchbreaks and shared use of small work spaces (14) . nevertheless, the transmission of covid-19 between workers has not been sufficiently studied: we are only aware of a study in singapore that identified a cluster of intrahospital hcw-to-hcw transmission (8) , and an anecdotal recent report from newspapers that described an outbreak in madrid, where 5 hcws acquired covid-19 after a lunch that took place in a hospital with over 25 participants, who were not wearing masks during the event (15) . in our study, the fact that cases peaked well before the peak in admitted covid-19 patients and the peak of diagnosed cases in the community, the lack of differences on the risk of infection among groups with different levels of exposure to covid-19, and the identification of several temporal clusters among certain groups suggest that transmission among hcws account for part of the cases. it is possible that several hcws became infected during the first days (either from undiagnosed covid-19 cases in the hospital, or from the community) and then in turn transmitted the infection to other hcws. three departments (oncology, dermatology and neurology) had most of the cases diagnosed in a short period of time, suggesting transmission in shared facilities or clinical meetings. there was also a temporal cluster among the heads of department, and a high proportion of the nurse supervisors affected, although the latter were not temporally related. these two groups were having daily meetings every day and also doing daily night shifts, and it is possible that there had been transmissions during the meetings or through fomites in the staff rooms or the emergency phone. in our hospital, workers were instructed to wear adequate ppe when contacting patients with confirmed or suspected covid-19. however, at the time of the study the use of face masks was neither recommended by health authorities for the general population (their compulsory use was only instituted for public transport on may 3 rd (16) and closed spaces on may 20 th (17)) nor specifically recommended for hcws that were not having contact with patients(18). during the period of february 20 th to march 13 th , training about covid-19 transmission and ppe was provided to hcws by the occupational health department. however, the training focused on the contact with covid-19 patients and did not specifically recommend wearing face masks when not interacting with patients. until approximately march 13 th to 16 th , hcws did not systematically wear face masks when being in contact with other hcws in the hospital facilities. after noting an increase in cases, most departments started systematically wearing face masks at all times in the hospital; shared meals during the night shifts were stopped, instructing workers to keep a distance of at least 2 metres in the refectory; and ward rooms were disinfected on march 13 th and 16 th . we cannot precisely determine the influence of these measures on covid-19 transmission in the hospital, but we presume that they were effective since the cases in hcws started declining after march 17 th despite an increasing number of patients admitted to the hospital with covid-19. it is unlikely that a better training on the use of ppe could explain the decrease in cases among hcws, as this training was not continued after march 13 th (except for one additional session in the pharmacy department on april 22 nd ). the prevalence of comorbidities was low and the clinical course was mild in most of the cases; our hcw were in general healthier and had a less severe clinical course than the series published in the general population (1, 4) and can probably be explained by a healthy worker effect, along as a younger age. also, the spanish ministry of health recommended that hcws with vulnerability to covid-19 complications (such as hcws aged over 60 years, pregnant women, and those with certain comorbidities) who could not be relocated to avoid covid-19 exposure should be preventively kept away from work (19): this was the case for 58 hcws in our hospital. nevertheless, some cases did experience severe complications such as bilateral pneumonia, thromboembolic disease or severe respiratory failure. in addition, cases had to stay away from work for a long time, for a median time of 20 days; this long sick leave, along with the workers preventively kept away from work, in a time of increasing healthcare demands due to the pandemic can have important effects due to understaffing, which entails an increase in workload and can produce additional stress on the already overworked staff that remains in the hospital(20). our study has two main limitations. first, we did not systematically test all the hcws in the hospital, but we limited our tests to symptomatic hcw presenting to the occupational health outpatient clinic. thus, we could have missed a proportion of workers with asymptomatic infection. second, the only available diagnostic test during the study period was sars-cov-2 pcr in nasopharyngeal swabs, which can have false negatives even in symptomatic cases: a recent review found a sensitivity of 76% (ci 95%: 59 -94) (21) . therefore, our study has probably underestimated the percentage of affected hcws. during the covid-19 pandemic health services had the challenge of ensuring sufficient ppes and that these were adjusted to quality standards. spanish health institutions had difficulties in providing adequate ppe to all healthcare workers during these times and we cannot exclude that some transmissions could be attributed to lack of adequate ppes or their suboptimal use. however, our results suggest that hcw-to-hcw transmission accounted for at least part of the covid-19 cases found in our hospital: this is a transmission route that is rarely mentioned in other studies (8) . we believe that this possibility should be further explored in other settings, and suggest preventive measures such as the systematic use of face masks at all times in the workplace, ensuring adequate working spaces to avoid overcrowding, and keeping a safety distance in meetings, clinical handouts, and work meals that could reduce the transmission of covid-19 in healthcare settings. also, surveillance of potential clusters could potentially be useful for contact tracing and prompt identification of transmissions (8) . in this study in a public hospital in spain, 11.1% of the hcws had symptoms consistent with covid-19 and microbiological confirmation of infection. the facts that cases among hcws peaked 2 weeks before the peak of admitted patients, that the risk of covid-19 was similar among three groups with different levels of occupational exposure, and that several temporal clusters were detected in specific departments and professions, suggest that hcw-to-hcw transmission accounted for part of the cases. in spite of a low prevalence of comorbidities and a mild clinical course in most cases, severe complications were diagnosed in some hcws and covid-19 caused long periods of sick leave. hospitalized patients with 2019 novel coronavirus-infected pneumonia in wuhan, china world health organization. coronavirus disease 2019. situation report-126 euro surveillance : bulletin europeen sur les maladies transmissibles = european communicable disease bulletin characteristics of and important lessons from the coronavirus disease 2019 (covid-19) outbreak in china: summary of a report of 72314 cases from the chinese center for disease control and prevention informe sobre la situación de covid-19 en personal sanitario en españa covid-19: protecting health-care workers asymptomatic sars-cov-2 infection in household contacts of a healthcare provider containment of covid-19 cases among healthcare workers: the role of surveillance, early detection, and outbreak management comunidad de madrid. informe diario de situación covid-19 risk factors of healthcare workers with clinical infectious diseases : an official publication of the infectious diseases society of america covid-19: a new work-related disease threatening healthcare workers covid-19: the daunting experience of healthcare workers in sardinia rapid assessment of regional sars-cov-2 community transmission through a convenience sample of healthcare workers, the netherlands beyond the assistance: additional exposure situations to covid-19 for healthcare workers. the journal of hospital infection un almuerzo de despedida celebrado en el gregorio marañón causa un brote de coronavirus en el hospital orden tma/384/2020, de 3 de mayo, por la que se dictan instrucciones sobre la utilización de mascarillas en los distintos medios de transporte y se fijan requisitos para garantizar una movilidad segura de conformidad con el plan para la transición hacia una nueva normalidad orden snd/422/2020, de 19 de mayo, por la que se regulan las condiciones para el uso obligatorio de mascarilla durante la situación de crisis sanitaria ocasionada por el covid-19 procedimiento de actuación para los servicios de prevención de riesgos laborales frente a la exposición al nuevo coronavirus (sars-cov-2). 5 de marzo de procedimiento de actuación para los servicios de prevención de riesgos laborales frente a la exposición al sars-cov-2. 30 de marzo de 2020 infectious diseases society of america guidelines on the diagnosis of covid-19 we thank all the nurses, physicians and occupational risk prevention technicians that took care of the hcws in the occupational health outpatient clinic during the study. all authors declare that they have no conflict of interest. this study was not funded. isg asked the research question, designed the study, analysed the data and wrote the first draft of the paper. mjm gathered the data. as gathered the data. pla designed the study and gathered the data. all authors were involved in interpretation of the data and commented on interim drafts. all authors have read and approved the final version of the article. key: cord-332083-135iic7m authors: xia, wei; fu, lin; liao, haihan; yang, chan; guo, haipeng; bian, zhouyan title: the physical and psychological effects of personal protective equipment on health care workers in wuhan, china: a cross-sectional survey study date: 2020-09-29 journal: j emerg nurs doi: 10.1016/j.jen.2020.08.004 sha: doc_id: 332083 cord_uid: 135iic7m introduction: the purpose of this study was to rapidly quantify the safety measures regarding donning and doffing personal protective equipment, complaints of discomfort caused by wearing personal protective equipment, and the psychological perceptions of health care workers in hospitals in wuhan, china, responding to the outbreak. methods: a cross-sectional online questionnaire design was used data were collected from march 14, 2020, to march 16, 2020, in wuhan, china. descriptive statistics and χ square analyses testing were used. results: standard nosocomial infection training could significantly decrease the occurrence of infection (3.6% vs 13.0%, χ(2) = 4.47, p < 0.05). discomfort can be classified into 7 categories. female sex (66.0% vs 50.5%, χ(2) = 6.37), occupation (62.7% vs 30.8%, χ(2) = 5.33), working at designated hospitals (44.8% vs 26.7%, χ(2) = 5.17) or in intensive care units (70.4% vs 57.9%, χ(2) = 3.88), and working in personal protective equipment for > 4 hours (62.2% vs 39.2%, χ(2) = 9.17) led to more complaints about physical discomfort or increased occurrence of pressure sores (all p < 0.05). psychologically, health care workers at designated hospitals (60.0% vs 42.1%, χ(2) = 4.97) or intensive care units (55.9% vs 41.5%, χ(2) = 4.40) (all p < 0.05) expressed more pride. discussion: active training on infection and protective equipment could reduce the infection risk. working for long hours increased the occurrence of discomfort and skin erosion. reducing the working hours and having adequate protective products and proper psychological interventions may be beneficial to relieve discomfort. coronavirus disease , which is now known to be caused by the severe acute respiratory syndrome coronavirus 2, has become a worldwide pandemic. [1] [2] [3] [4] the virus has now spread to 6 continents, endangering more than 10 million people. 5 the cumulative number of diagnosed patients had reached 85,204 in china as of june 29, 2020. 6 controlling the spread of the disease and providing medical care to the infected patients has been an unprecedented challenge. despite wearing personal protective equipment (ppe), there is evidence of health care workers (hcws) becoming infected. [7] [8] [9] in addition, owing to the heavy workload at the forefront and discomfort from wearing ppe for long periods, hcws, especially nurses in highworkload departments such as the emergency department, are suffering from considerable physical and mental burdens. [10] [11] [12] [13] owing to its rapid spread and highly contagious nature, as of february 11, 2020, 1,716 hcws in china had been infected by covid-19 according to a report from the chinese center for disease control and prevention. 14 hcws' main complaints include difficulty seeing owing to the misting of eye protection and difficulty breathing through protective masks. a proper method of donning and doffing ppe is highly important to protect hcws from inadvertent exposure. the national health commission of the people's republic of china has issued standard protocols for putting on and removing ppe according to different protective grades. 15 there are 3 levels of protection in china depending on different departments and degrees of exposure risk. equipment and n95 masks are required, and certain procedures must be followed in donning and doffing level ii ppe and above. (level iii protection is for those who are performing operations such as tracheal intubation that may produce aerosols in patients suspected of having, or confirmed to have, covid-19.) level ii protection is required for hcws working in emergency departments with patients with fevers; those who enter observation rooms or isolation wards with suspected cases; those who transport patients suspected of having, or confirmed to have, covid-19; and those who dispose of the corpses of patients who died owing to covid-19. because level ii ppe is used under most circumstances, with the exception of invasive operations, our research focused mainly on the use of level ii ppe. detailed donning and doffing procedures are described in the supplementary figure the purpose of this study was to rapidly quantify the safety measures of donning and doffing ppe, complaints of discomfort caused by wearing ppe, and the psychological perceptions of hcws in hospitals in wuhan, china, responding to the covid-19 outbreak. furthermore, we aimed to explore group differences in safety measures by infection status; complaints of discomfort by sex, working time, occupation, department, age, and workplace; and psychological perceptions by demographic characteristics. we used a cross-sectional design. we conducted an anonymous questionnaire survey (supplementary table 2 table 2 ). the authors were actively involved in frontline clinical care in wuhan, china, and the survey was based on their expert experience with ppe in the early phases of the covid-19 pandemic. there were 25 multiple-choice questions-6 had multiple-response options-with 5 questions per page, 5 pages in total. we used the questionnaire star survey program (wise talent information technology co, ltd) to collect the information. a link to the questionnaire was published on the wechat platform (tencent), the most widely and frequently used social networking platform in china. 16 it was open to all hcws in wuhan and those hcws came to support them. the survey was voluntary, with no incentives offered, and completing the survey was considered implied informed consent. we also attached a completeness check to the questionnaire, and responding to all 25 questions was mandatory; therefore, the participants had to choose at least 1 answer for each question listed. participants were not permitted to review after submitting the questionnaire; therefore, the participants could not change their answers once they were submitted. because our participants were all hcws in wuhan hospitals, we divided their demographic information as follows: the demographic variables included sex (male or female); age (20-30 years, 30-40 years, 40-50 years, and >50 years); occupation (physician, nurse, pharmacist, medical technician, or other); workplace (a designated hospital for patients critically ill with severe covid-19; an undesignated hospital for patients uninfected with covid-19; and fangcang hospital for patients with mild symptoms of covid-19); and department (general isolation ward, intensive care unit [icu], emergency department for patients with fevers, and other). the evaluation questionnaire included (1) whether or not the hcw had standard nosocomial infection training before treating patients in the wards, (2) whether or not the hcw was well acquainted with the standard operating procedure (sop) of donning and doffing ppe, (3) the presence of a full-length dressing mirror, (4) measures that the hcw thought were necessary to standardize the donning procedure, and (5) the best length of the hcw's hair at work. the respondents were also asked if they had been infected by covid-19 owing to exposure at work. we asked questions on the specific time that the hcw spent in the ward wearing ppe, their discomfort owing to ppe, and possible solutions. the questions included: time. (1) the time it took for an hcw to put on ppe, (2) the maximum time an hcw had spent in ppe, and (3) the maximum tolerance time of an hcw in ppe. discomfort in ppe at work. (1) discomfort: dizziness or palpitation; chest distress or dyspnea; nausea or vomiting; micturition desire; retroauricular pain (mask pressurerelated); thirst or dry throat; inconvenience at work; other symptoms of discomfort, for example, how an hcw felt in ppe, which was formatted as a multiple-response option. questions considering several vulnerable areas according to our clinical observation were also included: (2) was there mist on the hcw's goggles? (3) what were the effective methods that the hcw used to prevent misting in practice? (this question allowed for multiple-response options.) (4) did the hcw have pressure sores on their face? (5) in which areas did the hcw have pressure sores? (6) did the hcw have skin injury owing to gloves? (7) what type of glove-related skin damage did the hcw have? (1) discomfort that the hcw felt after doffing ppe, which was also a multiple-response option. (2) the first thing on an hcw's mind after doffing ppe. we asked about the amount of time off that the hcw felt was necessary to recover from work between shifts. the hcw's state of mind after donning ppe was also assessed. in a multiple-response-option format, the hcw was asked about experiencing 1 or more of 6 emotions: proud, excited, anxious, afraid, uncomfortable, or other. first, among the demographic information and safety measures, continuous variables were divided into categorical variables and were shown as numbers and percentages. second, complaints owing to ppe were reported (also as numbers and percentages), and the chi-square test or fisher exact test was used for intergroup comparisons (sex, occupation, age, workplace, department, and time in ppe). third, the psychological states of the hcw was described in a table categorized into different groups: occupation, age, sex, workplace, department, and time in ppe. a post hoc power analysis was performed to recommend the sample size for a replication study. all data were analyzed using spss version 26.0 (ibm corp). p values less than 0.05 were considered statistically significant. a total of 299 individuals agreed to participate, with 297 valid and complete questionnaires for a completion rate of 99.33%. the demographic characteristics are shown in supplementary regarding the measures that the hcws believed were necessary for standardizing the donning procedure, 14 hcws thought that only a full-length mirror was necessary (4.7%), 33 believed in having a checking monitor (11.1%), 15 thought that checking with a partner was adequate (5.1%), and 234 hcws attached importance to all of these measures to standardize the donning procedure (78.8%). for the best length of hair at work, 14 hcws believed that "fully shaved" was the best (4.7%), 89 thought that their hair should be as short as possible (23.0%), 90 believed that just tying it up was adequate (30.3%), and 104 thought that the length did not matter as long as it was properly handled when donning ppe (35.0%). table 1 explores the relationship between standard nosocomial training, familiarity with the sop, the availability of a dressing mirror, and the incidence of infection among the respondents. standard training on nosocomial infection before treating patients in the wards could significantly decrease the infection rate compared with the no-training group (3.6% vs 13.0%, x 2 ¼ 4.47, p < 0.05), whereas the unavailability of dressing mirrors could lead to a higher rate of infection (3.6% vs 13.0%, p < 0.05). the time it took the hcws to don ppe varied. a total of 52 hcws claimed to be able to don ppe within 10 minutes (17.5%), 111 needed 10 minutes to 15 minutes (37.4%), 79 needed 15 minutes to 20 minutes (26.6%), and 55 spent more than 20 minutes donning ppe (18.5%). after donning ppe, most of the hcws spent a maximum time of 4 hours to 6 hours (48.2%) or 6 hours to 8 hours (28.0%) working in it. for the maximum ppe tolerance time, 179 hcws believed that 4 hours to 6 hours was their limit (60.3%), 66 thought that 2 hours to 4 hours should be the maximum (22.2%), whereas 46 hcws believed that they could endure 6 hours to 8 hours in ppe at most (15.5%). all the types of discomfort with multiple-response options demonstrated a comparatively high occurrence (more than 40%, figure) . retroauricular pain (mask pressure-related) was the most reported complaint (81.8%), chest distress or dyspnea was the second (78.5%), inconvenience at work (for auscultatory tests, blood sample collection, and punctures) was the third (61.3%), followed by thirst or dry throat (60.3%), dizziness or palpitation (58.9%), micturition desire (55.6%), nausea or vomiting (42.1%), and other symptoms (14.8%). overall, 240 hcws reported misting on their goggles (81.8%). to prevent misting, most hcws thought it was useful to apply cleaning agents (63.3%) or spray antimist agents on their goggles or glasses (47.1%). a total of 173 hcws reported having pressure sores on their faces (58.3%), mainly distributed on the nose (81.0%), cheek (66.5%), forehead (45.1%), and retroauricular areas (43.6%). overall, 154 hcws reported glove-related skin damage (51.9%): eczema (59.1%), dry skin (57.8%), and skin erosion (53.9%) were the main injuries. the symptoms reported after doffing ppe included dizziness or palpitation (27.3%), chest distress or dyspnea (33.0%), nausea or vomiting (16.8%), and other symptoms (6.1%), whereas 160 hcws reported none of these symptom (55.2%). after doffing ppe, 130 hcws reported that the first thing on their mind was to drink water (43.8%), whereas 104 wanted to clean themselves (35.0%), and 36 wanted to rest (12.1%). discomfort in ppe, misting on goggles, pressure sores, and skin injury stratified by sex, occupation, age, workplace, department, and working time discomfort in ppe, misting on goggles, pressure sores, and skin injury stratified by sex, occupation, age, workplace, department, and working time are shown, respectively, in bar chart of the discomfort caused by personal protective equipment in the study sample. the respondents reported a relatively high level of discomfort. month 2020 volume -issue -www.jenonline.org table 3) . more than half the participants believed that an hcw needed 24 hours off between shifts (53.5%), and 27.61% felt that they needed 12 hours off between shifts. a post hoc power analysis was conducted to recommend the sample size for a future replication study on the basis of our results. here, we calculated the sample size using the ratebased sample size estimation formula in cross-sectional studies: n ¼ (zs/d)2 3 p(1-p). estimating the incidence of the survey population with 95% confidence level (zs is taken as 1.96), the prevalence, p, of discomforts in ppe is approximately 80% (p takes a value of 80%), q ¼ 1-p, and the tolerance, d, takes a value of 5%. in this case, the required sample size is calculated to be 246. considering the 5% invalid response, a sample size of 258 may meet the requirements. here, we add uniquely to the published literature by rapidly quantifying the safety measures of donning and doffing ppe, complaints of discomfort owing to ppe, and the psychological perceptions of hcws at hospitals in wuhan, china, responding to the covid-19 outbreak in march 2020. according to our online questionnaire survey, there was a high prevalence of uncomfortable symptoms suffered by the hcws during their fight against the covid-19 epidemic, although active and timely training was helpful for the effective prevention of infection. more complaints of discomfort were reported by women, physicians, nurses, and those working at a designated hospital or in an icu. the hcws working at a designated hospital or in an icu were prouder than their comparable groups after doffing ppe. training on nosocomial infection before treating patients in the wards is of considerable significance for preventing hcws from contracting covid-19, which was also demonstrated in previous studies. 17, 18 adding a dressing mirror at all sites would support staff during donning and doffing ppe, and it is an easy improvement to implement. we strongly recommend strictly adhering to the correct procedure for donning and doffing ppe. 15 timely, interactive training on the prevention of nosocomial infection and on the sop for wearing ppe can considerably reduce the risk of hcws' exposure to covid-19. studies have shown that adding computer stimulations or video-based learning methods could increase compliance and performance scores. [19] [20] [21] taking help from an assistant or partner, sometimes coupled with a mirror, was often resorted to month 2020 volume -issue -www.jenonline.org while donning ppe, and a hygienist supervised doffing. 22 we recommend using a full-length dressing mirror, being checked by a partner before entering the wards, and assigning a "dofficer" (or donning/doffing officer) for both donning and doffing ppe. hair length may not influence working or create extra risks of infection, but short hair is definitely easier to cover with a surgical cap, and saves time when putting on and removing ppe. according to a consensus by chinese experts, 23 hair should be cleaned with running water once ppe is removed, hair should be cleaned before taking a shower, and the head should be lowered when cleaning hair to keep the contaminated water out of the eyes, nose, and mouth. female hcws are more likely to suffer uncomfortable symptoms such as chest distress or dyspnea, retroauricular pain (mask pressure-related), thirst or dry throat, and inconvenience at work (for auscultatory tests, blood sample collection, and punctures), which suggests that there might be gender differences. these gender differences may be due to a difference in the types of work male and female hcws are assigned, the design of ppe, the cultural and gendered norms of expressing and reporting discomfort, or in both physical strength and psychological reaction. previous studies have shown that male hcws are prone to a higher rate of skin erosion than female hcws. 24 physicians, nurses, or hcws in an icu were more likely to complain about the inconvenience of working while wearing ppe than those in other positions or departments. this may be due to the different tasks and work intensity because clinical practices such as auscultatory tests, blood sample collection, and venipuncture are usually performed by physicians or nurses, and hcws in an icu treat patients with the most severe or complicated conditions; therefore, their work intensity or duration of ppe wear is much higher than that of those working in other departments. among the hcws working at designated hospitals for patients critically ill with severe covid-19, the prevalence of nausea or vomiting and inconvenience at work and pressure sores were significantly higher, further suggesting that the discomfort the hcws felt was positively correlated with their workload. complaints about inconvenience at work and pressure sores were more frequently reported by the hcws who worked in ppe for more than 4 hours; the longer the duration of wearing ppe, the greater the rate of complaints about discomfort. the following measures should be considered to alleviate discomfort owing to ppe: apply moisturizer before putting on and after taking off gloves; and refer to dermatologists if necessary. [25] [26] [27] we recommend routinely supplying protective supplies such as hand moisturizer. as for maskrelated discomfort, we recommend wearing a properly fitted mask and applying moisturizer or gel beforehand for lubrication. 28 we recommend nonirritating products for handwashing, and applying adhesive bandages on the portions of the skin in contact with the mask to help reduce friction. because of the possibility of conjunctival transmission of covid-19-first reported by a chinese expert 29 and later confirmed by scientific studies 30 -we strongly recommend using face shields in conjunction with goggles. 31 in addition, applying cleaning or antimist agents on the goggles might also help prevent misting. according to the results of the intergroup comparison, the working time in ppe at designated hospitals and in an icu should be reduced to approximately 4 hours, whereas in other workplaces and departments, 6 hours could be considered the maximum duration. a 24-hour break between shifts is recommended for hcws to be refreshed from fatigue and work pressure, but a 12-hour break between shifts might be more feasible. maintaining hydration before and after wearing ppe is recommended. timely psychological interventions that build confidence and relieve stress are important considerations. 32 according to a survey on hcws' emotional problems and coping strategies, positive attitudes in the workplace, clinical improvement of infected colleagues, and halting disease transmission among hcws after adopting strict protective measures alleviated their fear and supported them through the pandemic. 33 thus, a rational focus on facts and timely psychological assistance such as offering coping strategies and measures to provide adequate medical equipment to treat patients and prevent hcw infection are beneficial. we were motivated to conduct this research to share our useful experience and help reduce the discomforts of hcws worldwide during the covid-19 pandemic. many of our recommendations here were adopted at our hospital site, which is designated as a special hospital for patients with covid-19. these adoptions include every hcw receiving training on nosocomial infection before treating patients, adding dressing mirrors to assist with both donning and doffing ppe, creating 4-hour shifts for nurses, and staffing the emergency and icu departments with more nurses. medical isolation pads were used to prevent pressure sores caused by wearing n95 masks, and hand creams were provided to every hcw. informally, we found that most of the hcws in our hospital thought that these recommendations were very helpful, and future study is needed to confirm the efficacy and effectiveness of these recommendations. this study has several limitations. first, we used a questionnaire designed for the purposes of this study; further work is needed to test the validity and reliability of the survey. second, nurses working at a designated hospital made up most of the survey participants. third, owing to the covid-19 pandemic, this survey was administered online; therefore, the sampling was voluntary and web-based, creating possible selection bias, and we could not confirm that the participants were who they reported they were. as a crosssectional survey, no causation can be inferred. we conducted multiple group testing without applying a p value correction, which may have resulted in spuriously significant results. as our results demonstrated, discomfort owing to ppe is widespread among hcws, especially among nurses fighting covid-19 on the front lines. female sex as well as working under relatively high pressure for long hours closely correlated with the occurrence of uncomfortable symptoms and skin erosion. active training on the ppe donning and doffing procedure as well as education on nosocomial infection significantly reduced the risk of exposure. most of our study participants were nurses at a designated hospital for patients critically ill with severe covid-19, and these nurses are under tremendous pressure, which differs from ordinary times. we believe that working long hours in ppe as well as the heavy workload is quite comparable to work patterns in emergency departments, and thus our evidence and practical suggestions will be beneficial for daily emergency nursing practice. only 10% of our participants worked in the emergency department setting, and a replication study is warranted in this unique population alone. hcws in isolation wards should receive standard training on the ppe donning and doffing protocol, along with proper psychological encouragement and timely support. fighting the covid-19 pandemic is an unprecedented global challenge, and hcws are shouldering considerable responsibility as well as pressure. in light of this highly infectious disease, ppe remains the first-line recommendation for effective prevention; however, ppe-related discomfort is widely experienced by hcws. this study revealed the main types of discomfort, analyzed the relationship between demographic information and the occurrence of different physical complaints and mental states, and offered practical strategies for improvement. supplemental outbreak of pneumonia of unknown etiology in wuhan, china: the mystery and the miracle coronavirus infections-more than just the common cold clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus infected pneumonia in wuhan a novel coronavirus from patients with pneumonia in china the continuing 2019 ncov epidemic threat of novel coronaviruses to global healththe latest 2019 novel coronavirus outbreak in wuhan world health organization (who) coronavirus disease (covid-19): situation report-161 french high council for public health; french society for hospital hygiene. putting on and removing personal protective equipment uncertainty, risk analysis and change for ebola personal protective equipment guidelines h1n1 influenza infection in korean healthcare personnel survey of stress reactions among health care workers involved with the sars outbreak how to train health personnel to protect themselves from sars-cov-2 (novel coronavirus) infection when caring for a patient or suspected case physiologic and other effects and compliance with long-term respirator use among medical intensive care unit nurses discomfort and exertion associated with prolonged wear of respiratory protection in a health care setting epidemiology working group for ncip epidemic response, chinese center for disease control and prevention. the epidemiological characteristics of an outbreak of 2019 novel coronavirus diseases (covid-19) in china. article in chinese the national health commission of the people's republic of china. notice on issuing the technical guidelines for the prevention and control of novel coronavirus infection in medical institutions how the public uses social media wechat to obtain health information in china: a survey study evaluation of a pandemic preparedness training intervention of emergency medical services personnel the role of education in the prevention and control of infection: a review of the literature video based learning vs traditional lecture for instructing emergency medicine residents in disaster medicine principles of mass triage, decontamination, and personal protective equipment personal protective equipment in health care: can online infection control courses transfer knowledge and improve proper selection and use? using interactive computer simulation for teaching the proper use of personal protective equipment personal protective equipment for preventing highly infectious diseases due to exposure to contaminated body fluids in healthcare staff consensus of chinese experts on protection of skin and mucous membrane barrier for health care workers fighting against coronavirus disease 2019. dermatol ther. 2020 the incidence, risk factors and characteristics of pressure ulcers in hospitalized patients in china protecting healthcare staff from severe acute respiratory syndrome: filtration capacity of multiple surgical masks hand hygiene and skin health facemasks for the prevention of infection in healthcare and community settings pressure induced skin and soft tissue injury in the emergency department wang guangfa of peking university hospital disclosed the treatment situation on weibo, suspected of causing infection without wearing goggles a missing link between sarscov-2 and the eye?: ace2 expression on the ocular surface safety guidelines for sterility of face shields during covid 19 pandemic psychosocial effects of sars on hospital staff: survey of a large tertiary care institution healthcare workers emotions, perceived stressors and coping strategies during a mers cov outbreak we acknowledge all the health care workers who are providing patient treatment and care. conflicts of interest: none to report. the procedure for donning and doffing the personal protective equipment donning procedure in the clean zone for donning: (1) clean your hands according to the hand hygiene rules for hcw;(2) put on the medical protective mask (n95, and perform a seal-check; medical isolation pad could be used beforehand to prevent pressure sores); (3) put on the surgical cap; (4) put on the goggle; (5) put on the first layer of shoe coverings; (6) put on the protective clothing; (7) put on the first pair of gloves (covering the sleeves of the protective clothing); (8) put on the medical surgical mask; (9) put on the surgical cap (covering the upper edge of the goggle) and face shield (if available); (10) put on the gown; (11) put on the second layer of gloves (covering the sleeves of the gown); (12) put on the second layer of shoe coverings; (13) put on the face shield. doffing procedure 1. in the contaminated area: hand hygiene 2. in the first buffer room for doffing: (1) hand hygiene, take off the face shield;(2) hand hygiene, take off the shoe coverings(the outer layer); (3) hand hygiene, take off the gown with the gloves (the outer layer) together (attention: roll the gown inside-out without touching the contaminated outer surface, as shown in the supplementary video 1); (4) hand hygiene, take off the surgical cap and medical surgical mask; (5) hand hygiene, enter the second buffer room for doffing. 3. in the second buffer room for doffing: (1) hand hygiene, take off the protective clothing and the gloves (the inner layer) together (attention: roll the protective clothing inside-out without touching the contaminated outer surface, as shown in the supplementary video 2); (2) hand hygiene, take off the goggle;(3) hand hygiene, take off the surgical cap; (4) hand hygiene, take off the shoe coverings (the inner layer); (5) hand hygiene, take off the medical protective mask; (6) nasal vestibule cleansing; (7) put on the medical surgical mask. 4. in the clean zone: (1) hand hygiene;(2) take a shower.hcw, health care worker. the designated hospital, which is for severe and critical covid-19 patients. à the undesignated hospital, which is for patients uninfected with covid-19. x fangcang hospitals which belong to field mobile medical system are a number of movable cabins with multiple medical functions and the ability of rushing to the scene during emergency, during the epidemic of covid-19, they're mainly used for the treatment of mild patients. key: cord-297879-6xb25uhx authors: moncunill, g.; mayor, a.; santano, r.; jimenez, a.; vidal, m.; tortajada, m.; sanz, s.; mendez, s.; llupia, a.; aguilar, r.; alonso, s.; barrios, d.; carolis, c.; cistero, p.; choliz, e.; cruz, a.; fochs, s.; jairoce, c.; hecht, j.; lamoglia, m.; martinez, m.; moreno, j.; mitchell, r.; ortega, n.; pey, n.; puyol, l.; ribes, m.; rosell, n.; sotomayor, p.; torres, s.; williams, s.; barroso, s.; vilella, a.; trilla, a.; varela, p.; dobano, c.; garcia-basteiro, a. l. title: sars-cov-2 infections and antibody responses among health care workers in a spanish hospital after a month of follow-up date: 2020-08-25 journal: nan doi: 10.1101/2020.08.23.20180125 sha: doc_id: 297879 cord_uid: 6xb25uhx background. at the peak of the covid-19 pandemic in spain, cumulative prevalence of sars-cov-2 infection in a cohort of 578 randomly selected health care workers (hcw) from hospital clinic de barcelona was 11.2%. methods. a follow-up survey one month after the baseline (april-may 2020) measured sars-cov-2 infection by real time reverse-transcriptase polymerase chain reaction (rrt-pcr) and igm, iga, igg and subclasses to the receptor-binding domain of the sars-cov-2 spike protein by luminex. prevalence of infection was defined by a positive sars-cov-2 rrt-pcr and/or antibody seropositivity. results. the cumulative prevalence of infection at month 1 was 14.9% (84/565) and the seroprevalence 14.5% (82/565) for igm and/or igg and/or iga. we found 25 (5%) new infections in participants without previous evidence of infection at baseline (501) and two participants seroreverted for igm and/or igg and/or iga. among seropositive participants at baseline, igm and iga levels generally declined at month 1 (antibody decay rates of 0.49 (95% ci, 0.40-0.60) and 0.34 (95% ci, 0.26-0.44)), respectively. eight percent of the participants seroreverted for igm and 11% for iga. subjects reporting covid-19-like symptoms and laboratory and other technicians had higher risk of infection. the most frequent subclass responses were igg1 and igg2, followed by igg3, with higher levels of igg1, and only iga1 but no iga2 was detected. conclusions. our findings highlight the importance of a continuous and improved surveillance of sars-cov-2 infections in hcw, particularly in high risk groups. the decay of iga and igm levels have implications for seroprevalence studies using these isotypes. since the start of the coronavirus disease 2019 (covid-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (sars-cov-2), there have been two priority questions: to establish the prevalence and incidence of the infection and to unravel whether cases are protected from future reinfections and/or disease. among the 14.4 million confirmed sars-cov-2 infections and 603,691 deaths, as of july 2020 (https://covid19.who.int/), health care workers (hcw) continue to be one of the populations at higher risk due to close contact with covid-19 patients [1] . to date, it is estimated that more than 230,000 hcw have been infected and over 3000 have died of covid-19 [2] . nevertheless, most infections in hcw are asymptomatic or mild [1,3-6] but undetected infections can put their hcw fellows and patients at risk. prompt identification of cases by real time reverse-transcriptase polymerase chain reaction (rrt-pcr) screenings at hospitals is crucial to avoid new infections, isolations and quarantines in hcw. we previously reported the prevalence of sars-cov-2 in a cohort of 578 hcw from a large hospital from barcelona, spain, at the peak of the pandemic (baseline, march 28 th to april 9 th , 2020) [3] . we found that 9.3% (95% ci: 7.1-12.0) of the participants were seropositive and the cumulative prevalence of sars-cov-2 infection (considering a past or current positive result to either antibody testing or rrt-pcr) was 11.2% (95% ci: 8.8-14.1). the seroprevalence was relatively low but higher than the 7% estimated in the general population in barcelona one month later according to a large national seroprevalence study [7] . our findings were consistent to other studies in hcw [4, 5, 8] , although prevalence of up to 44% had also been reported in other countries [9] . importantly, 40% of the infections in our hcw cohort had not been previously detected [3] . this cohort is being followed up over a year to assess seroconversion and to understand naturally acquired immunity to covid-19 by evaluating the kinetics of antibody responses, including igg subclasses that have barely been explored [10, 11] . each igg subclass results in different antibody functions beyond viral neutralization through the differential binding of fc receptors or to complement, therefore this characterization is relevant to understand the mechanisms of immune protection [12] . here, we determined the prevalence of sars-cov-2 by antibody serology and rrt-pcr one month after the baseline. we measured igm, igg, and iga isotypes and subclasses, and assessed the factors associated with new infections as well as levels and kinetics of antibodies. we performed the second cross-sectional survey (april 27 th to may 6 th , 2020) of a 4-stage seroprevalence study in a cohort of 578 hcw who had been randomly selected and recruited from a total of 5598 hcw registered at hospital clínic de barcelona (hcb) [3] . participants were invited to a follow-up visit one month later. the study population included hcw who deliver care and services directly or indirectly to patients. further information can be found in supplementary materials. we collected a nasopharyngeal swab for sars-cov-2 rrt-pcr and a blood sample for antibody and immunological assessments. for participants isolated at home due to a covid-19 diagnosis or on quarantine, data and sample collection took place at their households. written informed consent was obtained from all study participants prior to study initiation. the study was approved by the ethics committee at hcb (ref number: hcb/2020/0336). data for each participant was collected in a standardized electronic questionnaire as it has been previously described [3] . methods for sars-cov-2 detection by rrt-pcr have follow the cdc-006-00019 cdc/ddid/ncird/ division of viral diseases protocol, as previously described. igg and iga subclass assays were performed following a similar luminex protocol (supplementary information) [14] . assay cutoff was calculated as 10 to the mean plus 3 standard deviations of log 10 -transformed mfis of 47 pre-pandemic controls. we tested the association between variables with the chi-square or fisher's exact test (for categorical variables), t student or wilcoxon sum rank tests (for continuous quantitative all rights reserved. no reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. . https://doi.org/10.1101/2020.08.23.20180125 doi: medrxiv preprint variables). univariable logistic models were run to evaluate factors associated with seropositivity. the effect of infection on antibody levels was analyzed using multilevel mixed-effects linear regression models incorporating gaussian random intercepts. this resulted in an estimate of the rates of antibody dynamics (decay), assuming a single exponential model. cumulative seropositive data was generated by selecting antibody levels at month 0 from individuals who were seropositive and antibody levels from month 1 in individuals who seroconverted from month 0 to month 1 and used for the analysis of antibody levels by different factors. the loess (locally estimated scatterplot smoothing) method was used to fit a curve to depict kinetics of antibody levels over time. statistical comparisons were performed at two-sided significance level of 0.05 and 95% confidence intervals (ci) were calculated for all estimations. analyses were undertaken using stata/se software version 16.1 and r studio version r-3.5.1 [15] (packages tidyverse and pheatmap). at month 1 visit, the cumulative prevalence of infection measured by either rrt-pcr or serology was 14.9% (84/565). nine participants had a positive rrt-pcr in the28 days following the initial study visit, and only 3 of these were detected at the second survey. the seroprevalence at month 1 was 14.5% (82/565) for either igm and/or igg and/or iga and 10.1% for igm, 11.3% for igg and 11.5% for iga (supplementary figure 1) . there was an absolute increment of 25 sars-cov-2 infections detected by rrt-pcr or serology, 5% all rights reserved. no reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. . https://doi.org/10.1101/2020.08.23.20180125 doi: medrxiv preprint among the 501 previously uninfected individuals (4% from all individuals at month 1). among these 25 individuals, infection was detected only by antibody serology (igm/igg/iga) in 16, by antibody serology and rrt-pcr in 7, and only by rrt-pcr in 2. the latter two seronegative individuals at month 1 had the positive rrt-pcr result more than 20 days before the survey. having had covid-19 compatible symptoms during the follow-up month was associated with experiencing a sars-cov-2 infection between month 0 and 1 with an or of 6.55 (95% ci 2.77-14.44) and a p<0.0001 in univariable analysis ( from the 54 seropositive hcw at baseline, 1 did not have sample available at month 1, 3/36 there were 5 seronegative hcws at month 1 but with a previous positive rrt-pcr. time since the first positive rrt-pcr ranged from 20 to 47 days. two of these hcw were asymptomatic. overall, igm and iga levels decreased from baseline to month 1, with antibody decay rates of 0.49 (95% ci, 0.40-0.60) and 0.34 (95% ci, 0.26-0.44), respectively ( table 2 ). the estimated time to seroreversion was 2.77 months (95% ci, 2.16-3.83, p-value < 0.0001) and 2.26 months (1.81-2.99, p-value < 0.0001) for igm and iga, respectively. in contrast, overall igg levels did not change between timepoints (table 2) , however, they decreased in 14/43 individuals and increased in 28/43 individuals ( figure 1 ). in adjusted models by days since onset of symptoms, antibody decay rates were similar (supplementary table 2 ). no all rights reserved. no reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. . https://doi.org/10.1101/2020.08.23.20180125 doi: medrxiv preprint differences in antibody kinetics were observed between asymptomatic and symptomatic individuals ( figure 1 ). iga levels were higher in seropositive hcw reporting having had covid-19 compatible symptoms (p<0.001) and a similar trend was observed for igm (p=0.057, figure 2 ). in addition, igm levels were higher in those seropositive hcw with symptoms for >10 days compared to seropositive hcw with shorter duration of symptoms, and a similar trend was observed for iga ( figure 2 ). age and sex were not associated with antibody levels ( figure 2 and supplementary figure 2 ). among hcw with positive rrt-pcr, igm levels peaked around 18 days since the first positive rrt-pcr, declined during 30 days after the positive rrt-pcr and then seemed to stabilize ( figure 3a ). iga levels followed a similar pattern with a slightly earlier peak. instead, igg levels increased until 40 days since the first positive rrt-pcr and no decrease was observed thereafter. similar kinetics were observed for antibody levels since onset of symptoms among seropositive hcw reporting having had symptoms ( figure 3b ). however, antibodies peaked some days later compared to the kinetics by days since rrt-pcr, and igm levels had a second lower peak around day 43. igg subclasses were measured only in igg seropositive samples. igg1 had the highest levels (and correlated with igg), followed by igg2, igg3, and igg4 ( figure 4a approximately 55% of the igg positive samples had detectable igg1 at month 0 and 1, and 60% and 79% had igg2 at month 0 and 1, respectively ( figure 4c ). around 45% and 64% had detectable igg3, and only 2% and 5% had igg4 at month 0 and 1, respectively (figure 4 c). the levels of most subclasses were maintained or increased from month 0 to 1, and seroreversion was only observed for igg2 and igg4. the samples with the highest levels of igg3 were igg1 negative ( figure 4b ). igg2 levels were higher in those igg seropositive hcw who had more than 10 days of symptoms compared to those with lower duration of symptoms but no other associated factors were found ( figure after one month of follow-up, we found a prevalence of 5% infections in hcw without a previous covid-19 diagnosis or evidence of past infection. this is a substantial amount of all rights reserved. no reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. . https://doi.org/10.1101/2020.08.23.20180125 doi: medrxiv preprint new infections considering that (i) the accumulated prevalence of infection at recruitment was 11.2%, (ii) the peak of the pandemic had already passed, (iii) ppe were available, (iv) regular rrt-pcr screenings had been implemented for several weeks at the hospital, and (v) the population had been confined for almost 1.5 months. interestingly, 64% of these infections were detected by serology only, probably reflecting infections occurring 1 to3 weeks before this survey. the single factor showing the highest strength of association with newly detected past or present sars-cov-2 infection was having had any symptom compatible with covid-19 in the previous month. around 60% of the infected individuals were asymptomatic, which is a higher proportion than what we had previously reported at baseline [3] , although in line with other studies reporting from 20 to 80% asymptomatic infections [16, 17] . consistently, we also found that working in a covid-19 unit was not associated with sars-cov-2 infections [3] but, curiously, we found here that technicians had an increased risk. this may be due to a decreased perception of risk in this group in contrast to other job categories that may take more precautions due to their direct contact with covid-19 patients. overall, igm and iga levels decreased substantially within a month and we estimated 2.77 and 2.26 months to igm and iga seroreversion, respectively. of note, from the 54 seropositive hcw at recruitment, 8% had seroreverted for igm and 11% for iga. time to seroreversion could not be calculated for igg because many individuals had an increase in the antibody levels probably due to the short time since infection and the delayed peak response of igg compared to iga and igm. the overall decrease of igm and iga but not igg and the observed curves of antibody levels by days since the first positive rt-pcr are consistent with previously reported data [18, 19] and with the expected patterns of an antibody response: igm and iga peak and then decline early after an infection and are typically short-term responses, while igg peaks and decays later to a stable titer that is maintained over time. also, igg has a half-life of 21 days (less for igg3) [20] , whereas halflife of iga and igm is 4-9 days [21, 22] . nevertheless, emerging data indicate that sars-cov-2 igg responses may wane quickly over time [23] to undetectable levels in a considerable proportion of individuals [24] . in our study, only 1 individual seroreverted for igg. antibody decay and seroreversion has enormous implications for the correct interpretation of serosurveys and could indicate waning protection and difficulties to achieve herd immunity. we confirmed that iga levels are higher in symptomatic individuals compared to the asymptomatic, and that igm levels positively correlate with the duration of symptoms [3]. all rights reserved. no reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. . https://doi.org/10.1101/2020.08.23.20180125 doi: medrxiv preprint despite not having found statistical differences for igg levels, increasing evidence suggest that levels and duration of antibodies are also higher in symptomatic and in moderate-severe patients than mild cases [24, 25] . in addition, we found 5 non-responders with more than 20 days since the first positive rrt-pcr. lower antibody levels in asymptomatic and mild cases and antibody non-responders would also affect seroprevalence studies and could imply lower protection to reinfection, although infected individuals also mount t cell responses [26] which may independently protect from infection. igg subclass responses increased from month 0 to month 1 in most of the individuals and, interestingly, many seroconverted during this month of follow-up for igg2 and igg3. overall, antibody levels were higher for igg1 than the other isotypes, following the relative abundance of these isotypes in plasma (igg1>igg2>igg3>igg4). we did not find any factor associated with igg subclass levels, with the exception of igg2 levels positively correlating with higher duration of symptoms. class-switch recombination to igg2 occurs after igg1 during the course of the immune response to limit inflammation [27] . while igg1 are typically pro-inflammatory and have effector functions resulting in infection clearance through efficient binding to fc receptors and complement, igg2 has a decreased binding [27] . the association of igg2 levels with duration of symptoms could reflect an anti-inflammatory response elicited by higher persistence of viruses and inflammation. conversely, igg2 could be contributing to persistence of symptoms through competition with igg1, causing less efficient clearance of viruses. the main limitation of this study is the small sample size for the analysis of factors associated with sars-cov-2 infection. in addition, there may be a recall bias in some reported data such as symptoms. in addition, antibody responses were only analyzed using one antigen and other viral proteins may elicit different responses in different populations [14] , thus we could have slightly underestimated the overall seroprevalence of infection. finally, kinetics of antibody responses and antibody decay rates have to be interpreted with caution as only two timepoints have been analyzed and rates may change depending on the baseline levels, and if levels are measured at the peak response or at the later steady-state period. data from next timepoints will complete kinetics information. our findings reinforce the importance of strengthening sars-cov-2 surveillance among hcw. despite having implemented regular rrt-pcr screenings, sars-cov-2 infections all rights reserved. no reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. . https://doi.org/10.1101/2020.08.23.20180125 doi: medrxiv preprint preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. . https://doi.org/10.1101/2020.08.23.20180125 doi: medrxiv preprint figure 1 . kinetics in sars-cov-2 antibody levels in individuals seropositive at recruitment and/or at month 1. levels (median fluorescence intensity, mfi) of igm, igg, and iga against receptor-binding domain (rbd) of the sars-cov-2 spike glycoprotein stratified by asymptomatic participants and participants who reported covid-19 compatible symptoms at recruitment (month 0, m0), month 1 (m1) or at both visits (m0&m1). lines indicate paired samples. yellow dots depict individuals who had detectable antibody levels at both study visits (igm n=33; igg n=42, iga n=41), burgundy and green dots show individuals who seroconverted for a particular isotype (igm n=24; igg n=22, iga n=24) and seroreverted (igm n=3; igg n=1, iga n=5), respectively, between visits. all rights reserved. no reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. . https://doi.org/10.1101/2020.08.23.20180125 doi: medrxiv preprint all rights reserved. no reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. . https://doi.org/10.1101/2020.08.23.20180125 doi: medrxiv preprint a and b) or the proportion of individuals within each category of the x-axis with respect to the total number of seropositive symptomatic (c). the center line of boxes depicts the median of mfis; the lower and upper hinges correspond to the first and third quartiles; the distance between the first and third quartiles corresponds to the interquartile range (iqr); whiskers extend from the hinge to the highest or lowest value within 1.5 × iqr of the respective hinge. wilcoxon rank test was used to assess statistically significant differences in antibody levels between groups. all rights reserved. no reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. . (n =77 for igm, 96 for igg, and 95for iga). the fitting curve was calculated using the loess (locally estimated scatterplot smoothing) method. shaded areas represent 95% confidence intervals. all rights reserved. no reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. . https://doi.org/10.1101/2020.08.23.20180125 doi: medrxiv preprint perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. . https://doi.org/10.1101/2020.08.23.20180125 doi: medrxiv preprint symptoms. (e) igg subclass levels stratified by days of symptoms. (a), (d) & (e) show data from accumulative month 0 and month 1 seropositive individuals: month 0 antibody levels from seropositive individuals at month 0 plus month1 antibody levels from individuals who seroconverted from month 0 to month 1. percentages indicate the proportion of seropositive subjects within each category of the x-axis. the center line of boxes depicts the median of mfis; the lower and upper hinges correspond to the first and third quartiles; the distance between the first and third quartiles corresponds to the interquartile range (iqr); whiskers extend from the hinge to the highest or lowest value within 1.5 × iqr of the respective hinge. wilcoxon rank test was used to assess statistically significant differences in antibody levels between groups. all rights reserved. no reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. . https://doi.org/10.1101/2020.08.23.20180125 doi: medrxiv preprint inclusion criteria included being an adult (>17 years) worker at hcb. exclusion criteria included: (a) absenteeism from workplace in the last 30 days (i.e., on vacation, sick leave, sabbatical), (b) working exclusively outside the hcb or maternity main buildings with no interaction with patients on a daily basis, (c) retirement or end-of-contract planned within one year after the recruitment date, and (d) participating in covid-19 clinical trials for preventive or treatment therapies. data included demographics, occupation, covid-19 risk factors, clinical information related to covid-19 compatible symptoms during the previous month, and history of rrt-pcr testing and contacts with cases. rna was extracted using the quick-dna/rna viral magbead kit (zymo) and the tecan dreamprep robot as described in the baseline manuscript [3] . five microliters of rna solution were used to amplify sars-cov-2 n1 and n2 regions, and the human rnase p gene as control, using probes, primers and cycling conditions described in the cdc-006-00019 cdc/ddid/ncird/ division of viral diseases protocol (3/30/2020 release, supplementary note 1). positive and negative controls were included in each batch of rna extractions and rrt-pcr reactions [3]. a positive result was considered if the ct values for n1, n2 and rnase p were below 40. samples discordant for n1 and n2 were repeated, and samples with a ct ≥ 40 for rnase p were considered as invalid. quantification of sars-cov-2 igm, igg and iga by luminex. rbd was coupled to magnetic microspheres from luminex corporation (austin, tx). antigen-coupled beads were added to a 96-well µclear® flat bottom plate (greiner bio-one, 655096) at 2000 beads/well in a volume of 90 µl/well of phosphate buffered saline +1% bovine serum albumin + 0.05% sodium azide (pbs-bn). next, 10 µl of test plasma samples (final dilution 1/500), 10 µl of a positive control (at four dilutions, 1/500, 1/2000, 1/8000 and 1/32000), 10 µl of two negative controls (final dilution 1/500), and 10 µl of pbs-bn as blank control were added per plate. plates were incubated at room temperature (rt) for 2 h on a microplate shaker at 500 rpm and protected from light. plates were washed three times with 300 µl/well of pbs-tween20 0.05%, using a magnetic manual washer (millipore, 43-285). a hundred microliters of biotinylated secondary antibody diluted in pbs-bn (anti-human igg, b1140, 1/1250; anti-human igm, b1265, 1/1000; or anti-human iga, sab3701227, 1/500; sigma) were added to all wells and incubated for 45 min at 500 rpm at rt and protected from light. plates were washed three times and 100 µl of streptavidin-r-phycoerythrin (sigma, 42250) diluted 1:1000 in pbs-bn were added and incubated during 30 min at 500 rpm, rt and protected from light. plates were washed three times, and beads resuspended in 100 µl of pbs-bn and kept overnight at 4 °c, protected from light. the next day, plates were read using a luminex xmap® 100/200 analyzer with 70 µl of acquisition volume per well, dd gate 5000-25000 settings, and high pmt option. crude median fluorescent intensities (mfi) and background fluorescence from blank wells were exported using the xponent software. sensitivity of the assay using samples from participants with positive sars-cov-2 rrt-pcr and with more than 10 days since the onset of symptoms was 97% for iga and igg and 75% for igm, with specificities of 100% for igg and igm and 98% for iga [3] . all rights reserved. no reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. . https://doi.org/10.1101/2020.08. 23.20180125 doi: medrxiv preprint quantification of sars-cov-2 igg and iga subclasses by luminex. rbd was coupled to magnetic microspheres from luminex corporation (austin, tx). briefly, 2000 antigencoupled microspheres in a volume of 50µl of pbs-bn were incubated with 50µl of test samples at the dilutions 1/100 and 1/500 during 1 hour on a microplate shaker at 500 rpm and protected from light. plates were washed three times with 300 µl/well of pbs-tween20 0.05%, using a magnetic manual washer (millipore, 43-285). for igg1 and igg3, 100 µl of secondary antibody (anti-human igg1-biotin from abcam ab9775 at 1/2000, and anti-human igg3-biotin from sigma-merck b3523 at 1/250) were added and incubated 45 min, followed by 3 washes and 100 µl of streptavidin-r-phycoerythrin (sigma-merck 42250 at 1/1000) incubated during 30 min at 500 rpm, rt and protected from light. for igg2 and igg4, 100 µl of secondary antibody (anti-human igg2 at 1/500, and anti-human igg4 at 1/500, from thermofisher, ma1-34655 and ma5-16716, respectively) were added and incubated 45 min, followed by 3 washes and 100 µl of a tertiary antibody (anti-mouse igg-biotin from sigma-merck b7401 at 1/40000 for igg2, and 1/10000 for igg4) incubated during 45 min at 500 rpm, rt and protected from light. after 3 washes 100ul of streptavidin-r-phycoerythrin was added and plates were incubated 30 min at 500 rpm, rt and protected from light. for iga1 and iga2, 100 µl of secondary antibody-phycoerythrin (mouse antihuman iga1 rpe conjugate and iga2 rpe conjugate at 1/200, from moss, 050520zd05 and 050520zd06, respectively) were added and incubated 30 min protected from light. finally, after 3 washes, beads were resuspended in 100µl of pbs-bn and read using the luminex xmap® 100/200 analyzer with 70 µl of acquisition volume per well, dd gate 5000-25000 settings, and high pmt option. at least 50 beads were acquired per sample. crude median fluorescent intensity (mfi) and background fluorescence from blank wells were exported. all rights reserved. no reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. . https://doi.org/10.1101/2020.08.23.20180125 doi: medrxiv preprint figure s2 . sars-cov-2 antibody levels by sex. levels (median fluorescence intensity, mfi) of igm (n=60), igg (n=66), and iga (n=71) against receptor-binding domain (rbd) of the sars-cov-2 spike glycoprotein. graphs show data from accumulative month 0 and month 1 seropositive individuals: month 0 antibody levels from seropositive individuals at month 0 plus month1 antibody levels from individuals who seroconverted from month 0 to month 1. percentages indicate the proportion of seropositive subjects within each category of the x-axis with respect to the total number of samples from each visit. the center line of boxes depicts the median of mfis; the lower and upper hinges correspond to the first and third quartiles; the distance between the first and third quartiles corresponds to the interquartile range (iqr); whiskers extend from the hinge to the highest or lowest value within 1.5 × iqr of the respective hinge. wilcoxon rank test was used to assess statistically significant differences in antibody levels between groups. all rights reserved. no reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. . https://doi.org/10.1101/2020.08.23.20180125 doi: medrxiv preprint figure s3 . levels of sars-cov-2 igg subclasses in igg seropositive individuals by demographic and clinical factors. sars-cov-2 antibody levels by demographic and clinical variables. levels (median fluorescence intensity, mfi) of igg, igg2, igg3 and igg4 against receptor-binding domain (rbd) of the sars-cov-2 spike glycoprotein stratified by (a) age, (b) sex, and (c) known contact with covid-19 cases. graphs show data from accumulative month 0 and month 1 seropositive individuals: month 0 antibody levels from seropositive individuals at month 0 plus month1 antibody levels from individuals who seroconverted from month 0 to month 1. percentages indicate the proportion of seropositive subjects within each category of the x-axis. the center line of boxes depicts the median of mfis; the lower and upper hinges correspond to the first and third quartiles; the distance between the first and third quartiles corresponds to the interquartile range (iqr); whiskers extend from the hinge to the highest or lowest value within 1.5 × iqr of the respective hinge. wilcoxon rank test was used to assess statistically significant differences in antibody levels between groups. all rights reserved. no reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. . https://doi.org/10.1101/2020.08.23.20180125 doi: medrxiv preprint figure s4 . sars-cov-2 iga subclass levels in a pool of samples from seropositive individuals. levels (median fluorescence intensity, mfi) of iga1 and iga2 against receptorbinding domain (rbd) of the sars-cov-2 spike glycoprotein in serial dilutions of a pool of seropositive samples. all rights reserved. no reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medrxiv a license to display the preprint in the copyright holder for this this version posted august 25, 2020. . https://doi.org/10.1101/2020.08.23.20180125 doi: medrxiv preprint epidemiology of and risk factors for coronavirus infection in health care workers exposed, silenced, attacked: failures to protect health and humans: a detailed protocol for a serological assay, antigen production, and test setup highly sensitive and specific multiplex antibody assays to quantify immunoglobulins m, a and g against sars-cov-2 antigens r: a language and environment for statistical computing. r foundation for statistical computing asymptomatic sars-cov-2 infection in belgian long-term care facilities prevalence of asymptomatic sars-cov-2 infection a systematic review of antibody mediated immunity to coronaviruses : antibody kinetics , correlates of protection , and association of antibody responses with severity of disease humoral immune responses in covid-19 patients: a window on the state of the art metabolic properties of igg subclasses in man metabolic properties of human iga subclasses metabolism of human gamma macroglobulins rapid decay of anti-sars-cov-2 antibodies in persons with mild covid-19 clinical and immunological assessment of asymptomatic sars-cov-2 infections key: cord-296306-xcomjvaa authors: rivett, lucy; sridhar, sushmita; sparkes, dominic; routledge, matthew; jones, nick k; forrest, sally; young, jamie; pereira-dias, joana; hamilton, william l; ferris, mark; torok, m estee; meredith, luke; curran, martin d; fuller, stewart; chaudhry, afzal; shaw, ashley; samworth, richard j; bradley, john r; dougan, gordon; smith, kenneth gc; lehner, paul j; matheson, nicholas j; wright, giles; goodfellow, ian g; baker, stephen; weekes, michael p title: screening of healthcare workers for sars-cov-2 highlights the role of asymptomatic carriage in covid-19 transmission date: 2020-05-11 journal: elife doi: 10.7554/elife.58728 sha: doc_id: 296306 cord_uid: xcomjvaa significant differences exist in the availability of healthcare worker (hcw) sars-cov-2 testing between countries, and existing programmes focus on screening symptomatic rather than asymptomatic staff. over a 3 week period (april 2020), 1032 asymptomatic hcws were screened for sars-cov-2 in a large uk teaching hospital. symptomatic staff and symptomatic household contacts were additionally tested. real-time rt-pcr was used to detect viral rna from a throat+nose self-swab. 3% of hcws in the asymptomatic screening group tested positive for sars-cov-2. 17/30 (57%) were truly asymptomatic/pauci-symptomatic. 12/30 (40%) had experienced symptoms compatible with coronavirus disease 2019 (covid-19)>7 days prior to testing, most self-isolating, returning well. clusters of hcw infection were discovered on two independent wards. viral genome sequencing showed that the majority of hcws had the dominant lineage b∙1. our data demonstrates the utility of comprehensive screening of hcws with minimal or no symptoms. this approach will be critical for protecting patients and hospital staff. despite the world health organisation (who) advocating widespread testing for sars-cov-2, national capacities for implementation have diverged considerably (who, 2020b; our world in data, 2020) . in the uk, the strategy has been to perform sars-cov-2 testing for essential workers who are symptomatic themselves or have symptomatic household contacts. this approach has been exemplified by recent studies of symptomatic hcws (hunter et al., 2020; keeley et al., 2020) . the role of nosocomial transmission of sars-cov-2 is becoming increasingly recognised, accounting for 12-29% of cases in some reports . importantly, data suggest that the severity and mortality risk of nosocomial transmission may be greater than for community-acquired covid-19 (mcmichael et al., 2020) . protection of hcws and their families from the acquisition of covid-19 in hospitals is paramount, and underscored by rising numbers of hcw deaths nationally and internationally (cook et al., 2020; cdc covid-19 response team, 2020) . in previous epidemics, hcw screening programmes have boosted morale, decreased absenteeism and potentially reduced long-term psychological sequelae (mcalonan et al., 2007) . screening also allows earlier return to work when individuals or their family members test negative (hunter et al., 2020; keeley et al., 2020) . another major consideration is the protection of vulnerable patients from a potentially infectious workforce (mcmichael et al., 2020) , particularly as social distancing is not possible whilst caring for patients. early identification and isolation of infectious hcws may help prevent onward transmission to patients and colleagues, and targeted infection prevention and control measures may reduce the risk of healthcare-associated outbreaks. the clinical presentation of covid-19 can include minimal or no symptoms (who, 2020a). asymptomatic or pre-symptomatic transmission is clearly reported and is estimated to account for around half of all cases of covid-19 (he et al., 2020) . screening approaches focussed solely on symptomatic hcws are therefore unlikely to be adequate for suppression of nosocomial spread. preliminary data suggests that mass screening and isolation of asymptomatic individuals can be an effective method for halting transmission in community-based settings (day, 2020) . recent modelling has suggested that weekly testing of asymptomatic hcws could reduce onward transmission by 16-23%, on top of isolation based on symptoms, provided results are available within 24 hr (imperial college covid-19 response team, 2020). the need for widespread adoption of an expanded screening programme for asymptomatic, as well as symptomatic hcws, is apparent (imperial college covid-19 response team, 2020; black et al., 2020; gandhi et al., 2020) . challenges to the roll-out of an expanded screening programme include the ability to increase diagnostic testing capacity, logistical issues affecting sampling and turnaround times and concerns about workforce depletion should substantial numbers of staff test positive. here, we describe how we have dealt with these challenges and present initial findings from a comprehensive staff screening programme at cambridge university hospitals nhs foundation trust (cuhnft). this has included systematic screening of >1000 asymptomatic hcws in their workplace, in addition to >200 symptomatic staff or household contacts. screening was performed using a validated real-time reverse transcription pcr (rt-pcr) assay detecting sars-cov-2 from combined oropharyngeal (op) and nasopharyngeal (np) swabs (sridhar et al., 2020) . rapid viral sequencing of positive samples was used to further assess potential epidemiological linkage where nosocomial transmission was suspected. our experience highlights the value of programmes targeting both symptomatic and asymptomatic staff, and will be informative for the establishment of similar programmes in the uk and globally. between 6 th and 24 th april 2020, 1,270 hcws in cuhnft and their symptomatic household contacts were swabbed and tested for sars-cov-2 by real-time rt-pcr. the median age of the hcws was 34; 71% were female and 29% male. the technical rt-pcr failure rate was 2/1,270 (0. 2% see materials and methods); these were excluded from the 'tested' population for further analysis. ultimately, 5% (n = 61) of swabs were sars-cov-2 positive. 21 individuals underwent repeat testing for a variety of reasons, including evolving symptoms (n = 3) and scoring 'medium' probability on clinical covid-19 criteria (tables 1-2) (n = 11). all remained sars-cov-2 negative. turn around time from sample collection to resulting was 12-36 hr; this varied according to the time samples were obtained. table 3 outlines the total number of sars-cov-2 tests performed in each screening group (hcw asymptomatic, hcw symptomatic, and hcw symptomatic household contact) categorised according to the ward with the highest anticipated risk of exposure to high; 'amber', medium; 'green', low; . in total, 31/1,032 (3%) of those tested in the hcw asymptomatic screening group tested sars-cov-2 positive. in comparison, 30/221 (14%) tested positive when hcw symptomatic and hcw symptomatic household contact screening groups were combined. as expected, symptomatic hcws and their household contacts were significantly more likely to test positive than hcws from the asymptomatic screening group (p<0. 0001, fisher's exact test). hcws working in 'red' or 'amber' wards were significantly more likely to test positive than those working in 'green' wards (p=0. 0042, fisher's exact test). all users of ffp3 masks underwent routine fit-testing prior to usage. cleaning and re-use of masks, theatre caps, gloves, aprons or gowns was actively discouraged. cleaning and re-use of eye protection was permitted for certain types of goggles and visors, as specified in the hospital's ppe protocol. single-use eye protection was in use in most scenario 1 and 2 areas, and was not cleaned and re-used. all non-invasive ventilation or use of high-flow nasal oxygen on laboratory-confirmed or elife digest patients admitted to nhs hospitals are now routinely screened for sars-cov-2 (the virus that causes covid-19), and isolated from other patients if necessary. yet healthcare workers, including frontline patient-facing staff such as doctors, nurses and physiotherapists, are only tested and excluded from work if they develop symptoms of the illness. however, there is emerging evidence that many people infected with sars-cov-2 never develop significant symptoms: these people will therefore be missed by 'symptomatic-only' testing. there is also important data showing that around half of all transmissions of sars-cov-2 happen before the infected individual even develops symptoms. this means that much broader testing programs are required to spot people when they are most infectious. rivett, sridhar, sparkes, routledge et al. set out to determine what proportion of healthcare workers was infected with sars-cov-2 while also feeling generally healthy at the time of testing. over 1,000 staff members at a large uk hospital who felt they were well enough to work, and did not fit the government criteria for covid-19 infection, were tested. amongst these, 3% were positive for sars-cov-2. on closer questioning, around one in five reported no symptoms, two in five very mild symptoms that they had dismissed as inconsequential, and a further two in five reported covid-19 symptoms that had stopped more than a week previously. in parallel, healthcare workers with symptoms of covid-19 (and their household contacts) who were self-isolating were also tested, in order to allow those without the virus to quickly return to work and bolster a stretched workforce. finally, the rates of infection were examined to probe how the virus could have spread through the hospital and among staff -and in particular, to understand whether rates of infection were greater among staff working in areas devoted to covid-19 patients. despite wearing appropriate personal protective equipment, healthcare workers in these areas were almost three times more likely to test positive than those working in areas without covid-19 patients. however, it is not clear whether this genuinely reflects greater rates of patients passing the infection to staff. staff may give the virus to each other, or even acquire it at home. overall, this work implies that hospitals need to be vigilant and introduce broad screening programmes across their workforces. it will be vital to establish such approaches before 'lockdown' is fully lifted, so healthcare institutions are prepared for any second peak of infections. clinically suspected covid-19 patients was performed in negative-pressure (à5 pascals) side rooms, with 10 air changes per hour and use of scenario 2 ppe. all other aerosol generating procedures were undertaken with scenario 2 ppe precautions, in negative-or neutral-pressure facilities. general clinical areas underwent a minimum of 6 air changes per hour, but all critical care areas underwent a minimum of 10 air changes per hour as a matter of routine. surgical operating theatres routinely underwent a minimum of 25 air changes per hour. viral loads varied between individuals, potentially reflecting the nature of the sampling site. however, for individuals testing positive for sars-cov-2, viral loads were significantly lower for those in the hcw asymptomatic screening group than in those tested due to the presence of symptoms (figure 1) . for the hcw symptomatic and hcw symptomatic contact screening groups, viral loads did not correlate with duration of symptoms or with clinical criteria risk score (figure 1 -figure supplement 1 and data not shown). three subgroups of sars-cov-2 positive asymptomatic hcw each individual in the hcw asymptomatic screening group was contacted by telephone to establish a clinical history, and covid-19 probability criteria ( table 1) were retrospectively applied to categorise any symptoms in the month prior to testing ( figure 2 ). one hcw could not be contacted to obtain further history. individuals captured by the hcw asymptomatic screening group were generally asymptomatic at the time of screening, however could be divided into three sub-groups: (i) hcws with no symptoms at all, (ii) hcws with (chiefly low-to-medium covid-19 probability) symptoms commencing 7 days prior to screening and (iii) hcws with (typically high covid-19 probability) symptoms commencing >7 days prior to screening ( figure 2 ). 9/12 (75%) individuals with symptom onset >7 days previously had appropriately self-isolated and then returned to work. one individual with no symptoms at the time of swabbing subsequently developed symptoms prior to being contacted with their positive result. overall, 5/1032 (0.5%) individuals in the asymptomatic screening group were identified as truly asymptomatic carriers of sars-cov-2, and 1/1032 (0.1%) was identified as pre-symptomatic. box 1 shows illustrative clinical vignettes. for the hcw asymptomatic screening group, nineteen wards were identified for systematic priority screening as part of hospital-wide surveillance. two further areas were specifically targeted for screening due to unusually high staff sickness rates (ward f), or concerns about appropriate ppe usage (ward q) ( figure 3 ). interestingly, in line with findings in the total hcw population, a significantly greater proportion of hcws working on 'red' wards compared to hcws working on 'green' wards tested positive as part of the asymptomatic screening programme ('green' 6/310 vs 'red' 19/ 372; p=0.0389, fisher's exact test). the proportion of hcw with a positive test was significantly higher on ward f than on other wards categorised as 'green' clinical areas (ward f 4/43 vs other 'green' wards 2/267; p=0.0040, fisher's exact test). likewise, amongst wards in the 'red' areas, ward q showed significantly higher rates of positive hcw test results (ward q 7/37 vs other 'red' wards 12/335; p=0.0011, fisher's exact test). ward f is an elderly care ward, designated as a 'green' area with scenario 0 ppe (tables 4-5) , with a high proportion of covid-19 vulnerable patients due to age and comorbidity. 4/43 (9%) ward staff tested positive for sars-cov-2. in addition, two staff members on this ward tested positive in the hcw symptomatic/symptomatic contact screening groups. all positive hcws were requested to self-isolate, the ward was closed to admissions and escalated to scenario 1 ppe ( table 5) . reactive screening of a further 18 ward f staff identified an additional three positive asymptomatic hcws (figure 4 ). sequence analysis indicated that 6/9 samples from hcw who worked on ward f belonged to sars-cov-2 lineage b. 1 (currently known to be circulating in at least 43 countries [rambaut et al., 2020] ), with a further two that belonged to b1. 7 and one that belonged to b2. 1. this suggests more than two introductions of sars-cov-2 into the hcw population on ward f (figure 4-figure supplements 1-2, table 6 ). it was subsequently found that two further staff members from ward f had previously been admitted to hospital with severe covid-19 infection. ward q is a general medical ward designated as a 'red' clinical area for the care of covid-19 positive patients, with a scenario 1 ppe protocol (tables 4-5). here, 7/37 (19%) ward staff tested positive for sars-cov-2. in addition, one staff member tested positive as part of the hcw symptomatic screening group, within the same period as ward surveillance. reactive screening of a further five staff working on ward q uncovered one additional infection. 4/4 sequenced viruses were of the b. 1 lineage (figure 4-figure supplements 1-2, table 6 ; other isolates could not be sequenced due to a sample ct value >30). all positive hcws were requested to self-isolate, and infection control and ppe reviews were undertaken to ensure that environmental cleaning and ppe donning/doffing practices were compliant with hospital protocol. staff training and education was provided to address observed instances of incorrect infection control or ppe practice. ward o, a 'red' medical ward, had similar numbers of asymptomatic hcws screened as ward f, and a similar positivity rate (4/44; 9%). this ward was listed for further cluster investigation after the study ended, however incorrect ppe usage was not noted during the study period. the majority of individuals who tested positive for sars-cov-2 after screening due to the presence of symptoms had high covid-19 probability ( table 7) . this reflects national guidance regarding self-isolation at the time of our study (uk government, 2020a). through the rapid establishment of an expanded hcw sars-cov-2 screening programme, we discovered that 31/1,032 (3%) of hcws tested positive for sars-cov-2 in the absence of symptoms. of 30 individuals from this asymptomatic screening group studied in more depth, 6/30 (20%) had not experienced any symptoms at the time of their test. 1/6 became symptomatic suggesting that the true asymptomatic carriage rate was 5/1,032 (0.5%). 11/30 (37%) had experienced mild symptoms prior to testing. whilst temporally associated, it cannot be assumed that these symptoms necessarily resulted from covid-19. these proportions are difficult to contextualise due to paucity of table 4 . the hospital's traffic-light colouring system for categorising wards according to anticipated covid-19 exposure risk. different types of ppe were used in each ( table 5) . red (high risk) amber (medium risk) green (low risk) areas with confirmed sars-cov-2 rt-pcr positive patients, or patients with very high clinical suspicion of covid-19 areas with patients awaiting sars-cov-2 rt-pcr test results, or that have been exposed and may be incubating infection areas with no known sars-cov-2 rt-pcr positive patients, and none with clinically suspected covid-19 point-prevalence data from asymptomatic individuals in similar healthcare settings or the wider community. for contrast, 60% of asymptomatic residents in a recent study tested positive in the midst of a care home outbreak (arons et al., 2020) . regardless of the proportion, however, many secondary and tertiary hospital-acquired infections were undoubtedly prevented by identifying and isolating these sars-cov-2 positive hcws. amber + red wards, for example intensive care unit, respiratory units with non-invasive ventilation facilities. all operating theatres, including facilities for bronchoscopy and endoscopy. 12/30 (40%) individuals from the hcw asymptomatic screening group reported symptoms > 7 days prior to testing, and the majority experiencing symptoms consistent with a high probability of covid-19 had appropriately self-isolated during that period. patients with covid-19 can remain sars-cov-2 pcr positive for a median of 20 days (iqr 17-24) after symptom onset (zhou et al., 2020) , and the limited data available suggest viable virus is not shed beyond eight days (wö lfel et al., 2020) . a pragmatic approach was taken to allowing individuals to remain at work, where the hcw had experienced high probability symptoms starting >7 days and 1 month prior to their test and had been well for the preceding 48 hr. this approach was based on the following: low seasonal incidence of alternative viral causes of high covid-19 probability symptoms in the uk (public health england, 2018), the high potential for sars-cov-2 exposure during the pandemic and the potential for prolonged, non-infectious shedding of viral rna (zhou et al., 2020; wö lfel et al., 2020) . for other individuals, we applied standard national guidelines requiring isolation for seven days from the point of testing (uk government, 2020b). however, for hcw developing symptoms after a positive swab, isolation was extended for seven days from symptom onset. our data clearly demonstrate that focusing solely on the testing of individuals fitting a strict clinical case definition for covid-19 will inevitably miss asymptomatic and pauci-symptomatic disease. this is of particular importance in the presence of falling numbers of community covid-19 cases, as hospitals will become potential epicentres of local outbreaks. therefore, we suggest that in the setting of limited testing capacity, a high priority should be given to a reactive asymptomatic screening programme that responds in real-time to hcw sickness trends, or (to add precision) incidence of positive tests by area. the value of this approach is illustrated by our detection of a cluster of cases in ward f, where the potential for uncontrolled staff-to-staff or staff-to-patient transmission could have led to substantial morbidity and mortality in a particularly vulnerable patient group. as sars-cov-2 testing capacity increases, rolling programmes of serial screening for asymptomatic staff in all box 1. clinical vignettes. self-isolation instructions were as described in table 2 . case 1: completely asymptomatic. hcw1 had recently worked on four wards (two 'green', two 'amber'). upon testing positive, she reported no symptoms over the preceding three weeks, and was requested to go home and self-isolate immediately. hcw1 lived with her partner who had no suggestive symptoms. upon follow-up telephone consultation 14 days after the test, hcw1 had not developed any significant symptoms, suggesting true asymptomatic infection. case 2: pre-symptomatic. hcw2 was swabbed whilst asymptomatic, testing positive. when telephoned with the result, she reported a cough, fever and headache starting within the last 24 hr and was advised to self-isolate from the time of onset of symptoms ( table 2) . her partner, also a hcw, was symptomatic and had been confirmed as sars-cov-2 positive 2 days previously, suggesting likely transmission of infection to hcw2. case 3: low clinical probability of covid hcw3 developed mild self-limiting pharyngitis three days prior to screening and continued to work in the absence of cough or fever. she had been working in' green' areas of the hospital, due to a background history of asthma. self-isolation commenced from the time of the positive test. hcw3's only contact outside the hospital, her housemate, was well. on follow-up telephone consultation, hcw3's mild symptoms had fully resolved, with no development of fever or persistent cough, suggesting pauci-symptomatic infection. case 4: medium clinical probability of covid hcw4 experienced anosmia, nausea and headache three days prior to screening, and continued to work in the absence of cough or fever. self-isolation commenced from the time of the positive test. one son had experienced a mild cough~3 weeks prior to hcw4's test, however her partner and other son were completely asymptomatic. upon follow-up telephone consultation 10 days after the test, hcw4's mild symptoms had not progressed, but had not yet resolved. case 5: high clinical probability of covid. hcw5 had previously self-isolated, and did not repeat this in the presence of new high-probability symptoms six days before screening. self-isolation commenced from the date of the new symptoms with the caveat that they should be completely well for 48 hr prior to return to work. all household contacts were well. however, another close colleague working on the same ward had also tested positive, suggesting potential transmission between hcws on that ward. areas of the hospital is recommended, with the frequency of screening being dictated by anticipated probability of infection. the utility of this approach in care-homes and other essential institutions should also be explored, as should serial screening of long-term inpatients. the early success of our programme relied upon substantial collaborative efforts between a diverse range of local stakeholders. similar collaborations will likely play a key role in the rapid, de novo development of comprehensive screening programmes elsewhere. the full benefits of enhanced hcw screening are critically dependent upon rapid availability of results. a key success of our programme has been bespoke optimisation of sampling and laboratory workflows enabling same-day resulting, whilst minimising disruption to hospital processes by avoiding travel to off-site testing facilities. rapid turnaround for testing and sequencing is vital in enabling timely response to localised infection clusters, as is the maintenance of reserve capacity to allow urgent, reactive investigations. there appeared to be a significantly higher incidence of hcw infections in 'red' compared to 'green' wards. many explanations for this observation exist, and this study cannot differentiate between them. possible explanations include transmission between patients and hcw, hcw-to-hcw transmission, variability of staff exposure outside the workplace and non-random selection of wards. it is also possible that, even over the three weeks of the study, 'red' wards were sampled earlier during the evolution of the epidemic when transmission was greater. further research into these findings is clearly needed on a larger scale. furthermore, given the clear potential for pre-symptomatic and asymptomatic transmission amongst hcws, and data suggesting that infectivity may peak prior to symptom onset (he et al., 2020) , there is a strong argument for basic ppe provision in all clinical areas. the identification of transmission within the hospital through routine data is problematic. hospitals are not closed systems and are subject to numerous external sources of infection. coronaviruses generally have very low mutation rates (~10 à6 per site per cycle) (sanjuán et al., 2010) , with the first reported sequence of the current pandemic only published on 12 th january 2020 (genbank, 2020). in addition, given sars cov-2 was only introduced into the human population in late 2019, there is at present a lack of diversity in circulating strains. however, as the pandemic unfolds and detailed epidemiological and genome sequence data from patient and hcw clusters are generated, realtime study of transmission dynamics will become an increasingly important means of informing disease control responses and rapidly confirming (or refuting) hospital acquired infection. importantly, implementation of such a programme would require active screening and rapid sequencing of positive cases in both the hcw and patient populations. prospective epidemiological data will also inform whether hospital staff are more likely to be infected in the community or at work, and may identify risk factors for the acquisition of infection, such as congregation in communal staff areas or inadequate access to ppe. our study is limited by the relatively short time-frame, a small number of positive tests and a lack of behavioural data. in particular, the absence of detailed workplace and community epidemiological data makes it difficult to draw firm conclusions with regards to hospital transmission dynamics. the low rate of observed positive tests may be partly explained by low rates of infection in the east of england in comparison with other areas of the uk (cumulative incidence 0.17%, thus far) (public health england, 2020). the long-term benefits of hcw screening on healthcare systems will be informed by sustained longitudinal sampling of staff in multiple locations. more comprehensive data will parametrise workforce depletion and covid-19 transmission models. the incorporation of additional information including staffing levels, absenteeism, and changes in proportions of staff self-isolating before and after the introduction of widespread testing will better inform the impact of screening at a national and international level. such models will be critical for optimising the impact on occupationally-acquired covid-19, and reducing the likelihood that hospitals become hubs for sustained covid-19 transmission. in the absence of an efficacious vaccine, additional waves of covid-19 are likely as social distancing rules are relaxed. understanding how to limit hospital transmission will be vital in determining (table 4) . hcws working across >1 ward were counted for each area. the left-hand y-axis shows the percentage of positive results from a given ward compared to the total positive results from the hcw asymptomatic screening group (blue bars). the right-hand y-axis shows the total number of sars-cov-2 tests (stars) and the number positive (pink circles). additional asymptomatic screening tests were subsequently performed in an intensified manner on ward f and ward q after identification of clusters of positive cases on these wards (figure 4) . asymptomatic screening tests were also performed for a number of individuals from other clinical areas on an opportunistic basis; none of these individuals tested positive. results of these additional tests are included in summary totals in table 1 , but not in this figure. infection control policy, and retain its relevance when reliable serological testing becomes widely available. our data suggest that the roll-out of screening programmes to include asymptomatic as well as symptomatic patient-facing staff should be a national and international priority. our approach may also be of benefit in reducing transmission in other institutions, for example carehomes. taken together, these measures will increase patient confidence and willingness to access healthcare services, benefiting both those with covid-19 and non-covid-19 disease. two parallel streams of entry into the testing programme were established and managed jointly by the occupational health and infectious diseases departments. the first (hcw symptomatic, and hcw symptomatic household contact screening groups) allowed any patient-facing or non-patientfacing hospital employee (hcw) to refer themselves or a household contact, including children, should they develop symptoms suggestive of covid-19. the second (hcw asymptomatic screening group) was a rolling programme of testing for all patient-facing and non-patient-facing staff working in defined clinical areas thought to be at risk of sars-cov-2 transmission. daily workforce sickness reports and trends in the results of hcw testing were monitored to enable areas of concern to be highlighted and targeted for screening and cluster analysis, in a reactive approach. high throughput clinical areas where staff might be exposed to large numbers of suspected covid-19 patients were also prioritised for staff screening. these included the emergency department, the covid-19 assessment unit, and a number of 'red' inpatient wards. staff caring for the highest priory 'shielding' patients (haematology/oncology, transplant medicine) were also screened, as were a representative sample of staff from 'amber' and 'green' areas. the personal protective equipment (ppe) worn by staff in these areas is summarised in table 5 . inclusion into the programme was voluntary, and offered to all individuals working in a given ward during the time of sampling. regardless of the table 6 continued on next page route of entry into the programme, the process for testing and follow-up was identical. wards were closed to external visitors. we devised a scoring system to determine the clinical probability of covid-19 based on symptoms from existing literature giacomelli et al., 2020; table 1 ). self-referring hcw and staff captured by daily workforce sickness reports were triaged by designated occupational health nurses using these criteria ( table 2) . self-isolating staff in the medium and low probability categories were prioritised for testing, since a change in the clinical management was most likely to derive from results. self-isolation and household quarantine advice was determined by estimating the pre-test probability of covid-19 (high, medium or low) in those with symptoms, based on the presence or absence of typical features (tables 1-2) . symptom history was obtained for all symptomatic hcws at the time of self-referral, and again for all positive cases via telephone interview when results became available. all individuals who had no symptoms at the time of testing were followed up by telephone within 14 days of their result. pauci-symptomatic individuals were defined as those with low-probability clinical covid-19 criteria ( table 2) . testing was primarily undertaken at temporary on-site facilities. two 'pods' (self-contained portable cabins with office, kitchen facilities, generator and toilet) were erected in close proximity both to the laboratory and main hospital. outside space was designed to enable car and pedestrian access, and ensure !2 m social distancing at all times. individuals attending on foot were given pre-prepared self-swabbing kits containing a swab, electronically labelled specimen tube, gloves and swabbing instructions contained in a zip-locked collection bag. pods were staffed by a team of re-deployed research nurses, who facilitated self-swabbing by providing instruction as required. scenario 1 ppe ( table 5 ) was worn by pod nurses at all times. individuals in cars were handed self-swabbing kits through the window, with samples dropped in collection bags into collection bins outside. any children (household contacts) were brought to the pods in cars and swabbed in situ by a parent or guardian. in addition to pod-based testing, an outreach hcw asymptomatic screening service was developed to enable self-swabbing kits to be delivered to hcws in their area of work, minimising disruption to the working routine of hospital staff, and maximising pod availability for symptomatic staff. lists of all staff working in target areas over a 24 hr period were assembled, and kits pre-prepared accordingly. self-swabbing kits were delivered to target areas by research nurses, who trained senior nurses in the area to instruct other colleagues on safe self-swabbing technique. kits were left in target areas for 24 hr to capture a full cycle of shift patterns, and all kits and delivery equipment were thoroughly decontaminated with 70% ethanol prior to collection. twice daily, specimens were delivered to the laboratory for processing. the swabbing, extraction and amplification methods for this study follow a recently validated procedure (sridhar et al., 2020) . individuals performed a self-swab at the back of the throat followed by the nasal cavity as previously described (our world in data, 2020). the single dry sterile swab was immediately placed into transport medium/lysis buffer containing 4m guanidine thiocyanate to table 7 . distribution of positive sars-cov-2 tests amongst symptomatic individuals with a positive test result, categorised according to test group and covid-19 symptom-based probability criteria (as defined in table 2 ). inactivate virus, and carrier rna. this facilitated bsl2-based manual extraction of viral rna in the presence of ms2 bacteriophage amplification control. use of these reagents and components avoided the need for nationally employed testing kits. real-time rt-pcr amplification was performed as previously described and results validated by confirmation of fam amplification of the appropriate controls with threshold cycle (ct) 36. lower ct values correspond to earlier detection of the viral rna in the rt-pcr process, corresponding with a higher copy number of the viral genome. in 2/1,270 cases, rt-pcr failed to amplify the internal control and results were discarded, with hcw offered a re-test. sequencing of positive samples was attempted on samples with a ct 30 using a multiplex pcr based approach (quick et al., 2017) using the modified artic v2 protocol (quick, 2020) and v3 primer set (artic network, 2020). genomes were assembled using reference based assembly and the bioinformatic pipeline as described (quick et al., 2017) using a 20x minimum coverage as a cut-off for any region of the genome and a 50.1% cut-off for calling of single nucleotide polymorphisms (snps). samples were sequenced as part of the covid-19 genomics uk consortium, cog-uk), a partnership of nhs organisations, academic institutions, uk public health agencies and the wellcome sanger institute. as soon as they were available, positive results were telephoned to patients by infectious diseases physicians, who took further details of symptomatology including timing of onset, and gave clinical advice ( table 2) . negative results were reported by occupational health nurses via telephone, or emailed through a secure internal email system. advice on returning to work was given as described in table 2 . individuals advised to self-isolate were instructed to do so in their usual place of residence. particularly vulnerable staff or those who had more severe illness but did not require hospitalisation were offered follow-up telephone consultations. individuals without symptoms at the time of testing were similarly followed up, to monitor for de novo symptoms. verbal consent was gained for all results to be reported to the hospital's infection control and health and safety teams, and to public health england, who received all positive and negative results as part of a daily reporting stream. swab result data were extracted directly from the hospital-laboratory interface software, epic (verona, wisconsin, usa). details of symptoms recorded at the time of telephone consultation were extracted manually from review of epic clinical records. data were collated using microsoft excel, and figures produced with graphpad prism (graphpad software, la jolla, california, usa). fisher's exact test was used for comparison of positive rates between groups defined in the main text. mann-whitney testing was used to compare ct values between different categories of tested individuals. hcw samples that gave sars cov-2 genomes were assigned global lineages defined by rambaut et al., 2020 using the pangolin utility (o'toole and mccrone, 2020). as a study of healthcare-associated infections, this investigation is exempt from requiring ethical approval under section 251 of the nhs act 2006 (see also the nhs health research authority algorithm, available at http://www.hra-decisiontools.org.uk/research/, which concludes that no formal ethical approval is required). written consent was obtained from each hcw described in the anonymised case vignettes. the citiid-nihr covid-19 bioresource collaboration ravi gupta harmeet gill; iain kean; mailis maes; nicola reynolds; michelle wantoch; sarah caddy anita furlong nathalie kingston; sofia papadia anne meadows naidine escoffery; heather jones; carla ribeiro nick brown; surendra parmar ; hongyi zhang; ailsa bowring; geraldine martell; natalie quinnell stefan grä f aloka de sa; maddie epping; andrew hinch conceptualization, data curation, formal analysis, investigation, methodology, project administration, writing -review and editing conceptualization, data curation, formal analysis, validation, methodology, project administration, writing -review and editing data curation, formal analysis, writing -original draft, project administration, writingreview and editing writing -original draft, project administration, writingreview and editing data curation, investigation, methodology, writing -original draft, project administration, writing -review and editing data curation, validation data curation, formal analysis, investigation data curation, writing -original draft conceptualization, writing -original draft, project administration, writing -review and editing data curation, supervision, writing -review and editing; the citiid-nihr covid-19 bioresource collaboration, conceptualization, data curation, formal analysis, funding acquisition, investigation, writing -original draft data curation, software; ashley shaw, supervision, project administration project administration, writing -review and editing data curation, formal analysis, supervision, project administration, writing -review and editing conceptualization, data curation, formal analysis, methodology, writing -original draft, project administration, writing -review and editing writing -original draft, project administration, writing -review and editing author orcids lucy rivett ethics human subjects: as a study of healthcare-associated infections, this investigation is exempt from requiring ethical approval under section 251 of the nhs act 2006 (see also the nhs health research authority algorithm presymptomatic sars-cov-2 infections and transmission in a skilled nursing facility artic network. 2020. artic-ncov2019 / primer_schemes covid-19: the case for health-care worker screening to prevent hospital transmission characteristics of health care personnel with covid-19 -united states exclusive: deaths of nhs staff from covid-19 analysed covid-19: identifying and isolating asymptomatic people helped eliminate virus in italian village asymptomatic transmission, the achilles' heel of current strategies to control covid-19 wuhan seafood market pneumonia virus isolate wuhan-hu-1 complete genome self-reported olfactory and taste disorders in sars-cov-2 patients: a crosssectional study temporal dynamics in viral shedding and transmissibility of covid-19 first experience of covid-19 screening of health-care workers in england report 16: role of testing in covid-19 control roll-out of sars-cov-2 testing for healthcare workers at a large nhs foundation trust in the united kingdom immediate and sustained psychological impact of an emerging infectious disease outbreak on health care workers epidemiology of covid-19 in a long-term care facility in king county software package for assigning sars-cov-2 genome sequences to global lineages to understand the global pandemic, we need global testing -the our world in data covid-19 testing dataset surveillance of influenza and other respiratory viruses in the uk to coronavirus (covid-19) in the uk 2020 multiplex pcr method for minion and illumina sequencing of zika and other virus genomes directly from clinical samples ncov-2019 sequencing protocol v2 a dynamic nomenclature proposal for sars-cov-2 to assist genomic epidemiology viral mutation rates a blueprint for the implementation of a validated approach for the detection of sars-cov2 in clinical samples in academic facilities stay at home advice covid-19: management of exposed healthcare workers and patients in hospital settings clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus-infected pneumonia in report of the who-china joint mission on coronavirus disease who. 2020b. covid-19 strategy update virological assessment of hospitalized patients with covid-2019 clinical course and risk factors for mortality of adult inpatients with covid-19 in wuhan, china: a retrospective cohort study additional files . source data 1. asymptomatic sars-cov-2 screening programme source data.. transparent reporting form sequencing data have been deposited in gsaid under accession codes epi_isl_433989-epi_-isl_433992, epi_isl_434005, epi_isl_433489-epi_isl_433497. researchers will be prompted to register and log on to the website to access the datasets (https://www.epicov.org/epi3/ frontend#1f1442). key: cord-282675-s4zmffj3 authors: sagaon-teyssier, luis; kamissoko, aliou; yattassaye, adam; diallo, fodié; rojas castro, daniela; delabre, rosemary; pouradier, fabrice; maradan, gwenaëlle; bourrelly, michel; cissé, mamadou; vidal, laurent; dembélé keïta, bintou; spire, bruno title: assessment of mental health outcomes and associated factors among workers in community-based hiv care centers in the early stage of the covid-19 outbreak in mali date: 2020-10-15 journal: health policy open doi: 10.1016/j.hpopen.2020.100017 sha: doc_id: 282675 cord_uid: s4zmffj3 • malian healthcare workers presented mental disorders in the early stage of covid-19. • nurses were at lower risk of mental health disorders than other worker categories. • women were at greater risk of mental health disorders than men. • a lack of protection equipment and nurses was associated with mental disorders. as of july 14, 2020, the covid-19 case-fatality rate in mali was the fifth highest in the world health organization's (who) african region, and the third highest among west african countries, with deaths representing 5.0% of total cases behind 6.2% and 5.1% in niger and burkina faso, respectively [1] . the first cases in mali were observed on march 25, 2020, over a month after the continent's first case, and 6 and 16 days after the two abovementioned countries, respectively. however, the number of cumulated cases in mali was much higher up to july 14: 2423 cases versus 1037 and 1099 cases in burkina faso and niger, respectively [1] . the lag between africa's first cases and those in mali did not create the same opportunity -in terms of prompt emergency preparation -which the lag in 2014 created during the ebola outbreak. moreover, international aid has slowed down because of covid-19's pandemic status. data for mali indicate that authorities' proactive decisions to contain the disease's spread, including commercial air traffic interruption, bans on mass gatherings and curfews, [2] have been insufficient. furthermore, as observed elsewhere, the public health response is being undermined by poor adherence to social distancing for different reasons [3, 4] . however, the most likely explanation for mali's higher vulnerability and poorer medical outcomes is its inherently weak healthcare system. compared with niger and burkina faso, the shortage of healthcare workers (hcw), health expenditures and infrastructure is more acute in mali [5] . more specifically, the country's dependency on foreign aid, unreliable medical equipment, difficulties to procure drugs [6] , staff attrition [7] , shortage of human resources (hr) [8, 9] and resulting degradation of working conditionsincluding increased workload [10] [11] [12] -all contribute to putting hcw who are on the front line fighting covid-19 under greater stress. added to this is the fact that care for covid-19 is only concentrated in 6 hospitals (5 in bamako and 1 in kati (19 km from bamako)) positioned at the top of the country's 4level healthcare pyramid [13] . the deleterious impact on hcw mental health [14, 15] because of the these structural problems and unpreparedness to contain covid-19 constitutes a serious public health issue [16] . unfortunately, data about mental health among hcw in mali is inexistent. however, the who asserts that increasing terrorism and insecurity in mali since 2012 are two factors that could have mental health implications for the general population [17] , and therefore this would include hcw. lessons learned from previous disease outbreaks in the world, such as sars-cov-1 in 2003, which resulted in severe psychological damage in hcw, highlighted the need to strengthen hcw mental resilience and their preparation for new outbreaks, by providing psychological first aid [18] [19] [20] [21] . despite this, a growing body of literature on the current covid-19 outbreak indicates a high prevalence of mental health disorders (mhd) in hcw, suggesting they were not adequately prepared for the magnitude of this pandemic [22] [23] [24] [25] [26] [27] [28] . studies found that between 20.1 and 64.7% of hcw had depressive symptoms, 35.1 to 51.6% anxiety symptoms, and 18.2 and 38.9% insomnia [25] [26] [27] 29] . mhd were often associated with gender, occupational differences, age [26, 27, 30] , place of work, and poor social support [31] . although structural factors were evoked in some cases as moderators of mhd risk [28] , no study to date has adequately examined their effect on hcw psychological outcomes. the current unprecedented pandemic is expected to have a long-lasting effect on mental health, especially for hcw [32, 33] . various studies all urge specific interventions to mitigate this effect, and to ensure hcw wellbeing during and after the pandemic [34] [35] [36] . training, social support, communication, and effective health equipment procurement are the primary elements suggested [37] [38] [39] [40] [41] [42] [43] . however, most of the abovementioned studies concerned developed countries, and focused primarily on front-line hcw. few studies to date have highlighted the importance of also taking into account non-front-line hcw, including community health workers (chw) and other non-medical staff [39, 44] . indeed, the absence of significant differences in psychological outcomes between these hcw and their front-line counterparts suggests that the risk of mhd during the current outbreak is similar in both groups [24] , especially in low-income countries [21] . furthermore, empirical studies performed to date were all conducted at an advanced stage (understood here as between 2 and 4 months after the outbreak started) in the countries investigated. they did not account for psychological profiles at outbreak onset (i.e., baseline) or in the early stage (understood here as the first 2 weeks). the mental health impact of covid-19 might be more severe on hcw with a fragile baseline profile [19, 35] . accordingly, while assessing mhd as the outbreak develops is vital to provide suitable psychological support, understanding profiles in the early stage is also essential to identify the most vulnerable hcw. covid-19's rapid spread throughout the world raised the question early on of whether african countries, especially those in sub-saharan africa (ssa), were adequately prepared or not [45] [46] [47] [48] . although the extent of the outbreak is currently less dramatic than initially feared, ssa authorities continue to give top priority to its containment, with little attention for preexisting serious public health concerns, especially the fight against malaria, tuberculosis and hiv. the potential interruption of prevention activities and treatment (e.g., antiretroviral treatment (art)) could harm the advances already made by ssa countries in this fight [49, 50] . fortunately, the work of non-governmental organizations (ngos) -which play a crucial role in controlling these diseases in ssa countries -is, at least in part, compensating for this lack of attention. furthermore, lessons learned by ngos from previous outbreaks and epidemics, especially hiv, are invaluable, and must be integrated into the overall response to covid-19 and future outbreaks [2, 51] . ngos providing healthcare services in mali are located at the bottom level of the country's 4-level healthcare pyramid, specifically at the community level. together with public community healthcare centers, they offer basic health services (e.g. essential medicines, maternity room, prevention and promotion of health, etc.) and are the main point of entry into the healthcare system. hcw in these healthcare structures screen for people with health conditions (e.g. people with covid-19 symptoms) requiring referral to structures in the 3 higher levels of care (district, regional, or national) [52,53]. the involvement of some malian ngos in health promotion and care activities has contributed to the achievement of important milestones in the country's response to other epidemics, such as hiv. this is especially true of arcad santé plus, the main malian ngo working on improving access to healthcare for people living with hiv (plwh) and other vulnerable populations since 1994. in december 2019, the number of plwh receiving hiv care in the ngo's 18 healthcare sites -located in 6 of the country's 10 administrative regions -was close to 29 000, or 26% of the plwh in mali. this is a substantial figure when one considers that only 35% of all plwh in mali had access to art in 2016 [54] . the main challenge faced by arcad santé plus in the current context is how to adopt government indications to prevent covid-19 in the workplace. this includes adjusting working hours and adapting hiv care centers' opening hours to reduce patient flow, while guaranteeing continued prevention and care for hiv and other health problems. on april 1, 2020 (6 days after the first covid-19 cases in mali), arcad santé plus launched the covidprev program whose main objective is to reduce the risk of covid-19 infection in its hcw (whether salaried or volunteers) and in plwh frequenting its centers [2] . covidprev's planned reorganization of activities and the continued uncertainty surrounding the outbreak, together with the need to guarantee hiv care-related activities, constitute a double burden for the ngo's workers. although not on the front line in the fight against covid-19, their mental health might be seriously harmed by these supplementary sources of mhd. prospective research is vital for ngos to achieve their objectives as part of national public health strategies. however, to our knowledge, no empirical evidence exists concerning the impact of covid-19 on public health in africa, and especially on the mental health of front-line and non-front-line hcw. arcad santé plus's activities directly related to the delivery of healthcare are performed by doctors, pharmacy doctors, midwives and nurses. activities related to prevention (e.g., health awareness, support for treatment adherence) and social support (e.g., moral, material) are primarily performed by chw (including community mobilizers and navigators) and psychosocial counselors. these two caregiver categories account for a large proportion of arcad santé plus's staff, and are continuously provided training for the promotion of health-, disease-and population-based issues, especially those related to hiv and stis. finally, administrative and logistics personnel ensure that the operation runs as smoothly as possible. in terms of the current covid-19 pandemic, hcw proximity to people -indoors and outdoors -makes them an important vector for disseminating information about covid-19 in order to protect plwh and other vulnerable populations. as one of arcad santé plus's top priorities has always been to protect its hcw from health problems -in order to ensure they can optimally provide hiv prevention and care -just days after the ngo's launch of its covidprev program, we implemented a public health and social sciences action research study aimed at providing the ngo with data about the current mental health state of its workforce, so that it could incorporate targeted measures in its covidprev program to protect its hcw. more specifically, this study explored individual and structural factors associated with depression, anxiety and insomnia in this workforce. data were collected from april 6 to 11, 2020 (i.e., two weeks after the first two covid-19 cases in mali) for hcw (salaried and volunteers) in arcad santé plus's 18 community-based hiv care centers, located in 6 administrative regions in mali (koulikoro, kayes, mopti, ségou, sikasso, gao) and in the capital bamako (fig. 1) . to be eligible, participants had to be at least 18 years old, and planned to work throughout the outbreak. a self-administered questionnaire collected the following information: demographic and socioeconomic data, self-perceived health status, mental health data, and basic covid-19 awareness. in addition, structural factors (characteristics) of the 18 hiv care centers (number of years open, hiv caseload, number of doctors, nurses, etc.) were provided by facility managers. study approval was obtained from the malian ethical committee (n°2020/57/ce/fmos/faph). analyses were performed for three mhd. the 9-item patient health questionnaire (phq-9) was used to assess depression and its severity [55] (total score from 0 to 27). the 7-item generalized anxiety disorder assessment (gad-7) was used to measure anxiety [56] (from 0 to 21). finally, the 7-item insomnia severity index (isi) assessed participant insomnia during the month preceding the survey [57] (from 0 to 28). all three tools were implemented in their validated french version [58] [59] [60] . analyses were performed for the three continuous scores. the following potential individual characteristics to explain individual variability in the outcomes were tested: age (continuous variable); gender (woman=1 vs man=0); marital status: married/cohabitating (=1) or single/separated/divorced/widowed (=0); a three-category variable for the number of financially dependent family members, constructed using the median as the cutoff (none, 1 to 7, and >7); self-perceived health status: "good" (=1) or "very good"/"excellent" (=0); worker type classified into a four-category variable as follows: i) doctors, pharmacy doctors and midwives ii) nurses; iii) chw (including community mobilizers and navigators) and psychosocial counselors; iv) other, including administrative and logistics personnel (secretary, driver, etc.). it is important to note that the worker type variable reflects not only the activity type, but is also a proxy of the worker's education level: higher than high-school for nurses, midwives, pharmacy doctors and doctors; and lower than highschool for the other worker categories. to measure preexisting (i.e., prior to the covid-19 outbreak) serious work-related psychological damage resulting from ethical or moral transgression in the workplace, participants answered the 9item moral injury event scale (mies) [61] . two sub-scores -perceived transgression (ranging from 1 to 36) and perceived betrayal (1 to 18) -were constructed, and specified as continuous variables. finally, basic covid-19 awareness was assessed using unicef's "fact or fiction" 10-question quiz (appendix 1) with a score ranging from 0 (no correct response) to 10 (all responses correct). the following potential structural characteristics (all continuous variables) to explain variability in the outcomes due to differences between hiv care centers were tested: the number of years since the center opened, and 6 other variables assessing the density of personnel (per 100 patients) for 6 worker categories (required to permit separate analyses): i) doctors, ii) pharmacy doctors, iii) midwives, iv) nurses, v) chw and vi) psychosocial counselors. healthcare supply characteristics were tested by constructing dichotomous variables indicating whether the center offered (=1) or not (=0) each of the following 12 services: i) medical consultation for the general population, ii) specific medical consultation for key populations, iii) hiv screening, iv) hiv care for adults and/or pediatric care, v) delivery of arv drugs, vi) biomedical analyses, vii) nursing care, viii) community-based talks and/or distribution of condoms and lubricants, ix) psychological care, x) hiv pre-exposure prophylaxis (prep) delivery, xi) hiv post-exposure prophylaxis (pep) delivery, and xii) social/financial support. equipment characteristics were tested by constructing 5 dichotomous variables indicating whether each center had (=1) or not (=0) the following items: i) an electricity generator, ii) air conditioning, and iii) a refrigerator. with regard to personal protective equipment (ppe), dichotomous variables indicated the availability (=1) or not (=0) of: i) face masks, ii) gowns, iii) safety goggles, and iv) gloves. finally, an indicator recorded potential drug stock-outs during the previous 6 months (between october 2019 and march 2020) (yes=1 or no= 0). descriptive statistics were calculated for the sample. for the phq-9, gad-7 and isi scores, statistics included the proportion of non-zero scores, their mean (standard deviation), and median with interquartile range [iqr] . furthermore, for descriptive purposes only, cutoffs of ≥ 10, ≥ 7, and ≥ 15 were used to distinguish severity for depression, anxiety, and insomnia, respectively [55] [56] [57] [58] [59] . estimations were performed with the outcomes specified as continuous dependent variables. a general mixture model (gmm) with a negative binomial (nb) distribution was used (see appendix 2 for details on the estimation strategy). all statistical analyses were conducted using r software, version 4.0.0 [62] . of the 188 workers identified in arcad santé plus's 18 community-based hiv care centers, 135 were working at the time of data collection and intended to continue working throughout the outbreak (table 1 ) (study population). most were men (60.7%) and median age was 40 years iqr [33] [34] [35] [36] [37] [38] [39] [40] [41] [42] [43] [44] [45] [46] (see table 1 for more details on individual characteristics). with respect to study outcomes, table 1 shows that mean scores were lower than their corresponding variances, justifying the choice to use an nb distribution instead of a poisson distribution (assuming equal mean and variance). phq-9, gad-7 and isi scores indicated high prevalences of depression, anxiety and insomnia symptoms in the study population (71.9%, 73.3% and 77%, respectively). furthermore, 18.5% and 21.5% of all participants had moderate/severe depression and anxiety, respectively, whereas only 2.2% had severe/moderate insomnia. half the hiv care centers opened before 2012 (table 1) , the median years of activity being 8 iqr [7] [8] [9] [10] [11] [12] . in terms of hr availability, median densities (all values per 100 patients) of doctors and nurses were 0.13 (iqr[0.06-0.20]) and 0.10 (iqr[0.02-0.20]), respectively. the most disadvantaged hiv care centers (i.e., the 25% corresponding to the 1 st quartile) had extremely limited hr, especially nurses (fewer than 0.02) and chw (fewer than 0.01), and no psychosocial counselors. the most severe ppe shortages concerned goggles (no center), face masks (only 5 centers) and gowns (only 6 centers). eight centers had experienced drug stock-outs in the 6 months preceding the survey, mostly of arvs and drugs for opportunistic infections (see table 1 for more details on services provided). a constructed using correct responses to unicef's "fact or fiction" quiz (see appendix 1); b presented only for descriptive purposes, as multivariable models were estimated using these scores as continuous variables. c two hiv care centers declared 1 midwife. the density of midwives for these two centers was 0.01 and 0.02 per 100 plwh, respectively, although the median and iqr were equal to 0. d these variables were not tested in the model as they were constant across all 18 hiv care centers (i.e., response was similar for all centers). the lr-test comparing 1-level and 2-level null models concluded that variability in phq-9 (depression), gad-7 (anxiety) and isi (insomnia) scores were due to both individual characteristics and differences in hiv care center characteristics, as indicated by the icc: 33%, 31% and 16% of the total variability, respectively (see bottom of table 3 ). bivariate analysis in table 2 showed that the higher the number of financially-dependent family members, the higher the risk of depression (p=0.037) for those who self-perceived good health status (versus very good/excellent, p=0.029), and for those with a strong perception of work-related moral transgression (p<0.001) and/or betrayal (p=0.010). nurses had the lowest risk of depression (p=0.006). with regard to structural characteristics, medical consultations for the general population (p<0.001) and arv delivery (p=0.036) were associated with a higher risk of depression. in contrast, depression was less likely in hcw in centers with a higher density of nurses (p=0.045) and greater availability of face masks (p=0.039). multivariable analysis (see table 3 ) showed that depression was 60% more likely in women than in men the bivariate analysis for anxiety (table 2) shows that women were at higher risk than men (p=0.027). anxiety was also more likely in participants who perceived they had good health status (versus very good/excellent) (p=0.009). in terms of structural characteristics, face mask availability was associated with a lower risk of anxiety in participants working in centers which provided them (p=0.041). the higher risk of anxiety in women was a tendency in the multivariable model ( 01-1.04) ). face mask availability was associated with a 62% lower risk of anxiety in participants working in centers which provided them (irr: 0.38, 95%ci(0.21-0.67)). furthermore, the risk of anxiety was lower in workers in hiv care centers with a higher density of nurses, decreasing by 95% per additional nurse per 100 plwh (irr: 0.05, 95%ci(0.01-0.62)). sleeping disorders were more frequent in women (p=0.030), in those perceiving good health status (p=0.024), and in those perceiving work-related betrayal (p=0.002) ( table 2 ). in terms of structural characteristics, insomnia was related to face mask availability (p=0.008). multivariable analysis (table 3) confirmed the higher risk of insomnia in women (53%) (irr: 1.53, 95%ci(1.12-2.09)). insomnia also increased by 6% per one-point increase in the perceived workplace betrayal score (irr: 1.06, 95%ci(1.02-1.09)). worker category was related with the risk of insomnia, which was 49% lower in nurses than other hcw (irr: 0.51, 95%ci(0.29-0.93)). finally, the only structural factor associated with insomnia was face mask availability. participants working in care centers where they were available had a 43% lower risk of insomnia (irr: 0.57, 95%ci(0.38-0.86)). mhd prevalence was high in our study population during the early stage (i.e., first 2 weeks) of the covid-19 outbreak in mali. more specifically, of arcad santé plus's 135 non-front-line hcw who participated in the present study, 71.9%, 73.3% and 77% declared at least one symptom of depression, anxiety, and insomnia, respectively. these figures are much higher than those in studies of front-line hcw [27, 29] (61.7%, 51.6% and 38.9%, respectively) performed in countries at an advanced stage (i.e., between 2 to 4 months) after the outbreak. furthermore, these countries had relatively more developed healthcare systems. this result suggests that arcad santé plus's non-front-line hcw might be more vulnerable to deteriorating psychological outcomes as the current covid-19 outbreak progresses and after it ends. the present article demonstrates that mhd in hcw were related not only to individual characteristics, but also to hiv care center characteristics. specifically, the risks of having these conditions were 51%, 62% and 43% lower, respectively, in people working in hiv care centers providing face masks than in people working elsewhere. a lack of masks was also the only structural factor linked to insomnia. furthermore, depression and anxiety were 91% and 95%, respectively, less likely to occur in hcw in hiv care centers with a higher density of nurses. mental health in arcad santé plus's chw in mali seemed to be associated with uncertainty about covid-19 at the beginning of the outbreak, as suggested by the relationship between the (un)availability of face masks and insomnia, depression, and anxiety. however, the risk of the latter two mhd seemed to be also related with preexisting contexts in hiv care centers, such as hr scarcity, especially nurses. the temporary reorganization of activities planned by arcad santé plus as part of its purpose-built covidprev program -including fewer working hours, lower patient flow and a reduction of some services -should attenuate workers' exposure to psychological disorders by reducing their workload [63] . however, it is vital to also include screening for psychological disorders and suitable treatment, as these same changes may themselves lead to psychological problems [64] [65] [66] . in addition, adequate ppe must be guaranteed for hcw, especially face masks, one of the most important tools in stopping the spread of covid-19 [37] . the relationship discovered between the density of nurses in hiv care services and workers' psychological outcomes not only highlights areas for improvement in the management of mental health among arcad santé plus's hcw during the current covid-19 outbreak, but also provides insight into how these workers' performance in hiv-related care could be improved in the short and long terms. our results indicate that managers should investigate whether better reallocation of nursing resources is needed according to hiv caseload, whether more nurses need to be hired, and whether improvements in doctor-nurse task-shifting -an increasingly important care strategy, especially in ssa -is necessary, especially seeing as arcad santé plus continues to expand its offer to include more non-hiv specific health-related services. furthermore, including chw as a full hcw category (albeit voluntary) in all organizational changes is crucial, both during and after the current covid-19 outbreak, as these workers play an essential role in healthcare in ssa [67] [68] [69] . chw account for a large proportion of arcad santé plus's staff (20% of respondents in the present article) and their activities are central to what makes this ngo attractive to people benefitting from its services. they are crucial in reaching key populations and promoting retention in hiv prevention and care programs. their contribution to the introduction of pre-exposure prophylaxis (prep) for hiv among men having sex with men in mali is just one example of this [70] . the role of chw (not just in mali) in connecting the most vulnerable people with healthcare systems during the current covid-19 outbreak highlights the importance of strengthening chw workforces long after this pandemic ends. this observation is not new to africa, a continent where the work of chw during the last decade in the field of hiv has led to successful testing of new task-shifting models and has strengthened the argument for the demedicalization of prevention and care [67] [68] [69] [71] [72] [73] ]. however, the success of any new healthcare service model which incorporates chw as key actors, depends not only on financial sustainability, but also on the capability of the healthcare system to limit staff attrition and to protect them -and all hcw -from potential health problems, including mhd [7] . the abovementioned implications of the relationship between structural factors and hcw mhd are supported by our results for individual factors. apart from nurses, all other worker categoriesincluding chw -were at greater risk of depression and insomnia (respectively, 60% and 49% more than nurses). these results confirm the importance of taking into account non-front-line hcw mental health in related analyses [39, 44] . the present work reflects the higher work-related psychological risk among women in healthcare-related professions observed in the literature [24, 63] . despite their nonfront-line status, this finding could be explained -at least partly -by both the importance which women in general seem to attach to psychosocial support [74] , and occupational exposure related to hiv care delivery [75] [76] [77] . furthermore, our results contribute to the existing literature by demonstrating that work-related factors are not the only source of mhd. factors related to the day-to-day life of hcw were also strongly associated with the risk of depression. indeed, depression was over twice as likely in participants with financially-dependent family members. family responsibilities imply not only a supplementary workload, but also mental efforts that may lead to increased levels of depression [78] . the psychological distress related to medical decisions running counter to hcw morals and ethics is an important mental health dimension. in the present article, this distress was assessed using the moral injury event scale, as suggested by greenberg et al., and walton et al. [41, 44] . more specifically, our results showed that the risks of depression and anxiety were higher in workers who perceived work-related moral transgression, while the risk of insomnia was higher in those perceiving workrelated betrayal. given their non-front-line status in terms of covid-19 care, and the fact that we assessed psychological outcomes during the early stage of the outbreak, this result would seem to be mostly explained by psychological distress linked to their hiv care-related activities. the complex context which these workers are confronted with may also result in their having to take decisions which run counter to their moral and ethical values. the lack of arv delivery during stock-outs, the slowdown in international funding for the treatment of opportunistic infections, and external intimidation because of the services they offer (e.g., counseling for men who have sex with men), are three examples where such decisions might be made. this present article has limitations. first, although the study sample was exhaustive -in that it included hcw in arcad santé plus's 18 healthcare services in mali working in the early stage of the covid-19 outbreak and reporting that they intended to continue to work throughout the outbreak -the sample size was nevertheless small. this meant that the relationship between certain structural factors and individual psychological outcomes could not be measured, as there was insufficient variability within some structures. however, the comparability of our results for individual factors with existing literature demonstrates that implementing suitable techniques -in our case gmm with an nb distribution -helped to overcome the limitations imposed by the small sample size. second, our sample was not representative of the population of malian hcw. despite the difficulties they face, the working conditions of arcad santé plus's non-front-line hcw are relatively less difficult than those of their counterparts in the general malian health system. considering that in mali there is a greater-than-usual shortage of hr (0.036 medical professionals per 100 patients) with respect to arcad santé plus hiv care centers (0.23 per 100 patients, which interestingly matches the minimum recommended by the who [79] ), our results for non-front-line hcw most likely underestimate the current situation regarding mental health in the national healthcare system. finally, the short questionnaire used prevented the collection of more detailed information about participants' working and living conditions. however, the choice to use a short questionnaire was governed by necessity in order to limit desirability bias, and by a desire not to overburden respondents who were already having to adapt to constantly changing circumstances related to covid-19. despite these limitations, the analyses conducted here provide evidence of non-negligible mhd affecting hcw in arcad santé plus's care network in the early stage of the covid-19 outbreak. in light of this action research, results from the first analyses (carried out 1 week after data collection) prompted the ngo to add two new actions to its covidprev program: i) the distribution of a large quantity of basic ppe, including face masks, gloves, and cleaning products; and ii) the drafting and distribution of an information leaflet presenting the current mental health situation of its hcw, in order to promote self-help in this population through the program's specifically developed fora, given governmental restrictions on movement. we aim to conduct further research to investigate whether and to what degree the covid-19 outbreak aggravates mhd in this population. more broadly, the results of the present article provide evidence-based arguments that should be taken into account in malian healthcare policy. irrespective of the covid-19 outbreak, conducting situational research is crucial to understand how and to what extent the physical and mental health of hcw is related to working and living conditions. psychosocial support is a key element in the management of day-to-day work-related activities, and becomes indispensable during serious health shocks such as the current covid-19 outbreak. the long-established trustful relationship between arcad santé plus and users of its hiv prevention and care services is a crucial factor in ensuring the dissemination of key covid-19 messages in mali. indeed, the arrival of this new disease has underlined the huge importance of hcw -front-line and non-front-line -and has placed them at the core of health systems worldwide. however, the outbreak has also revealed weaknesses in integrating non-front-line hcw in the response to covid-19, especially hcw in ngos who perform crucial health-related activities. these people should have been integrated early on after the outbreak, not only as important vectors for information dissemination and prevention, but also as a group whose health and well-being are at stake and need to be protected. one of the main lessons to be learned from previous outbreaks and which the current covid-19 pandemic reminds us of, is that "not being on the front line" does not mean "not needing support to reinforce the front line". the effectiveness of the international response to pandemic outbreaks, and in general the effectiveness of public health strategies at national and local levels, depend on the capacity of hcw to fully and competently perform their duties within the healthcare system. estimations were carried out with the outcomes specified as continuous dependent variables to avoid any loss of information that might result from their dichotomization, that is to say, underestimation of the variability, and reduced power to estimate outcomes' relationships with explanatory variables [80, 81] . however, this choice was methodologically challenging as it required us to implement a model adapted to non-negative dependent variables with skewed distributions and often overdispersed and zero-inflated. given this context, the most suitable method to estimate the associated factors to the outcomes in this article was the general mixture model (gmm) with a negative binomial (nb) distribution [82, 83] . this was preferred to the poisson-type distribution, as indicated by log-likelihood ratio test (lr-test), which rejected the null hypothesis where overdispersion is absent. gmm models have often been shown to be better adapted to non-count data, and a better alternative to tobit and two-part models [83] . the restricted (residual) maximum likelihood estimation method was implemented in order to manage estimations with small samples [84, 85] . for each outcome the estimation strategy consisted in: 1) verifying the pertinence of using a multilevel model. a 2-level null model with random intercepts was estimated and compared with a 1-level null model using the lr-test. this comparison allowed us to verify whether there was any outcome variability arising from differences between hiv care centers. the intra-class correlation coefficient (icc) -adapted to the gmm -was estimated to assess the amount of outcome variability arising from structural differences [86] [87] [88] . single estimations were performed for each explanatory variable at the individual level. each estimation was compared with the null model using the lr-test in order to assess the contribution of the corresponding explanatory variable. eligibility of individual-level variables for inclusion in the multivariable model was based on the following criteria: p-value < 0.2 and/or lr-test p-value < 0.1 (i.e. significant contribution to the model fitting). the step-wise forward selection procedure was implemented and the final multivariable model for individual characteristics chosen on the basis of the aic criterion. this best-fit model for individual factors was used to conduct a bivariate analysis for the structural factors (i.e., hiv care center structural 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gravity estimating poisson pseudo-maximum-likelihood rather than log-linear model of a logtransformed dependent variable small sample methods for multilevel modeling: a colloquial elucidation of reml and the kenward-roger correction getting started with the glmmtmb package n the coefficient of determination r2 and intra-class correlation coefficient from generalized linear mixed-effects models revisited and expanded n.d repeat personal victimization: random effects, event dependence and unexplained heterogeneity reliability of environmental sampling culture results using the negative binomial intraclass correlation coefficient logistic regression using sas: theory and application designed the study. l.s.-t. and a.k. conducted the statistical analyses key: cord-282280-5pggpbrq authors: doornekamp, laura; van leeuwen, leanne; van gorp, eric; voeten, helene; goeijenbier, marco title: determinants of vaccination uptake in risk populations: a comprehensive literature review date: 2020-08-27 journal: vaccines (basel) doi: 10.3390/vaccines8030480 sha: doc_id: 282280 cord_uid: 5pggpbrq vaccination uptake has decreased globally in recent years, with a subsequent rise of vaccine-preventable diseases. travellers, immunocompromised patients (icp), and healthcare workers (hcw) are groups at increased risk for (severe) infectious diseases due to their behaviour, health, or occupation, respectively. while targeted vaccination guidelines are available, vaccination uptake seems low. in this review, we give a comprehensive overview of determinants—based on the integrated change model—predicting vaccination uptake in these groups. in travellers, low perceived risk of infection and low awareness of vaccination recommendations contributed to low uptake. additionally, icp were often unaware of the recommended vaccinations. a physician’s recommendation is strongly correlated with higher uptake. furthermore, icp appeared to be mainly concerned about the risks of vaccination and fear of deterioration of their underlying disease. for hcw, perceived risk of (the severity of) infection for themselves and for their patients together with perceived benefits of vaccination contribute most to their vaccination behaviour. as the determinants that affect uptake are numerous and diverse, we argue that future studies and interventions should be based on multifactorial health behaviour models, especially for travellers and icp as only a limited number of such studies is available yet. vaccinations have proven to play a major role in the prevention and control of many infectious diseases. however, in the twenty-first century, vaccination programs face multiple challenges [1] . the first one is the need for fast development of effective and safe vaccines for new (re-)emerging pathogens. the recent sars-cov-2 pandemic is an example in which a vaccination is highly desired and may reduce the enormous impact of the current pandemic. the second challenge in the field of vaccinology is the upcoming trend of vaccine hesitancy and declining vaccination uptake. vaccine hesitancy is recognised by the world health organization (who) to be one of the ten threats to global health [2] . vaccination uptake is declining globally, resulting in a rise in outbreaks of vaccine-preventable diseases (vpd) [3] . for instance, measles cases have increased-up to 300 percentover the past years [4] . vaccine hesitancy has predominantly received attention in the light of parents rejecting the national immunization programs. however, low vaccination uptake among adult populations also raises concerns [5] . adults are progressively at risk for infectious diseases because life expectancy increases [6] , the incidence of chronic diseases that require immunosuppressive treatment rises [7] , and international travel expands [8] . other determinants will play a role in vaccination uptake in adult populations as compared to children. adults who are recommended to get vaccinated can be divided into several risk groups. risk populations in this context are defined as groups of human individuals with an increased risk of acquiring a (severe) infection due to their behaviour, health, or occupation. to get a broad overview of determinants that play a role in the vaccination uptake among risk groups, this review will focus on three distinct risk groups which consult vaccination clinics frequently, namely: "travellers, immunocompromised patients (icp) and healthcare workers (hcw)". travellers comprise a risk population, as at their destinations they can be exposed to infectious diseases they have not encountered before. traveller vaccination guidelines are available to protect this population. these guidelines do not only differ per destination but are also dependent on the activities the travellers will undertake and the duration of their stay. additionally, the country of origin is of importance, because of the endemicity of infectious diseases and therefore natural exposure, and national immunization programs. moreover, travellers who are not properly vaccinated for their trip are not only at risk for getting sick themselves, they can also create a public health concern for communicable diseases, as they could carry an infection back home to a naïve population [9] . icp have an increased risk for serious illnesses caused by infectious diseases due to a diminished function of their immune system. the compromised state of their immune system can be induced by either an underlying disease or the treatment of a disease. as a consequence of fast-developing immunosuppressive therapies for e.g., auto-immune diseases and malignancies, icp are a constantly growing population [7] . therefore, optimal protection of this vulnerable group is of utmost importance. hcw are another risk category for acquiring infectious diseases. their occupation brings them in close contact with patients, that possibly carry an infectious disease. furthermore, hcw are not only personally at risk, they may also put their-mostly vulnerable-patients at risk when they work while carrying an infection [10] . on top of that, hcw play an important role in providing their (immunocompromised or travelling) patients with information or recommendations regarding vaccinations. vaccination uptake varies between risk populations and there may be differences in determinants that play a role in this behaviour. to find general patterns each risk group will be studied separately. however, as travellers, icp, and hcw are interrelated, we aim to learn from similarities and differences between these groups. if we understand risk populations' motivations and concerns, we might be able to address these either separately or combined by effective interventions. to get a better overview of all determinants that have a possible impact on uptake, we classified these in a model of health behaviour change. an abundance of behaviour change models are available that describe determinants affecting preventive health behaviour [11] . in 2003, the integrated change (i-change) model was developed by de vries et al. [12] . this model is derived from the attitude-social norm-self-efficacy (ase) model and integrates several other models, among which are the often-used health belief model (hbm) and the theory of planned behaviour (tpb) (supplementary table s1 ). according to the i-change model, vaccination behaviour is shaped by the intention to get vaccinated which is subject to barriers and facilitators. intention is established by motivation, awareness, information, and predisposing determinants. as this i-change model comprises a wide variety of determinants that are used by other studies, for example those based on the hbm and ase model, we use this model as a conceptual framework. with this comprehensive review, we aim to better understand determinants that play a role in the uptake of vaccinations in travellers, icp, and hcw and explore similarities and differences in these three groups. hereby, we aim to create a solid ground for the development of evidence-based interventions to increase vaccination uptake in the populations that need optimal prevention strategies for infectious diseases. we performed a systematic database search on 19 february 2020. we performed one search for all three risk groups (supplementary file s1). for each risk groups we combined search terms for vaccination uptake and health behavioural models. we searched the following databases: embase, medline, cinahl, web of science core collection, eric, psychinfo, and socindex. as determinants of vaccination uptake may vary over time, we limited our search to studies published during the last ten years (between 1 january 2010 and 1 january 2020). we excluded research papers written in another language than english. all records were retrieved into an endnote database. duplicates were removed and titles and abstracts were screened (by ld). thereafter, papers were sorted in the three different groups and full texts articles were reviewed for suitability using inclusion and exclusion criteria (by l.d. and l.v.l.) using endnote x9. studies were included if they met all of the following criteria: (1) at least 75% of the included respondents are either icp (patients with autoimmune diseases, malignancies, hiv, asplenia and solid organ or stem cell transplantations) or travellers (including travellers visiting friends and relatives (vfr), short-and long-term business travellers) or hcw (including general practitioners (gps), physicians and nurses working in a hospital); (2) addressing self-reported cognitive determinants that may explain vaccination uptake; and (3) being performed in western countries (defined as europe, north america, australia, and new zealand). we excluded studies that focussed on: (1) children; (2) hcw who care for populations other than the icp defined in our study (e.g., paediatricians, elderly home physicians) or who are not directly involved in the care for this group (e.g., pharmacists, dentists); (3) future healthcare workers (e.g., medicine or nursing students); (4) uptake of the national immunization programme (e.g., hpv vaccination); (5) hypothetical vaccinations (e.g., a hiv vaccine); (6) vaccinations administered in outbreak situations (e.g., h1n1 vaccine, ebola vaccine); (7) other very specific target groups (e.g., roma travellers, migrants, pregnant women; and (8) predisposing factors exclusively. we also excluded qualitative studies and non-peer reviewed articles such as conference abstracts. in case any doubt or disagreement between the two researchers who performed the study selection (by l.d. and l.v.l.) arose, the specific papers were discussed in a plenary session with all co-authors. the following background characteristics from included studies were extracted: first author and year of publication; study design; enrolment period; enrolment site; sample size; study population; theoretical framework; and targeted outcome variables. extracted data was collected in microsoft excel 2016 and the presence and impact of determinants were rated in separate sheets per study group (by l.d. and l.v.l.). random samples were taken to check the data extraction and disagreements were discussed plenary with all co-authors. furthermore, the quality of studies was assessed using the the axis tool [13] , which is a screening tool specifically designed for cross-sectional studies, as those in our review, and includes 20 items relevant to this design. scores 1-9 are rates as low, 10-14 as medium and 15-20 as high. the i-change model was used to organize all determinants that could explain vaccination uptake. a simplified version of this model is shown in figure 1 . the following concepts are used: (1) predisposing factors, including baseline characteristics of studied populations; (2) information factors, including information retrieved via media, social contacts and hcw; (3) awareness, of the infectious agent being present or a vaccine being available; (4) knowledge (either examined or self-evaluated), about the consequences of the infection, or about the efficacy and duration of protection of vaccination; (5a) perceived risk of the infection, which is divided into perceived severity of the disease and perceived susceptibility to get infected; (5b) perceived risk of vaccination, including vaccine-specific considerations such as fear of side-effects and trust in the effectiveness of the vaccine; (6) attitude, defined as a person's disposition to respond favourably or unfavourably to vaccinations [14] , often reflected by a person's general believes about vaccinations; (7) social influence, which can be social norms imposed by family, friends or religion, but also recommendations from a healthcare professional or tour guide; (8) self-efficacy, defined as beliefs in one's own capacity to perform certain behaviour [15] ; (9) intention to behaviour, expressed by people before they perform the behaviour; (10) barriers and facilitators, that withhold individuals from or enable them to certain behaviour, such as time, costs, or accessibility. vaccines 2020, 8, x for peer review 5 of 39 figure 1 . simplified i-change model summarizing the studied determinants that could predict vaccination uptake. we used a simplified version of the i-change model applied to vaccination uptake. uptake is shaped by the intention to get vaccinated which is subject to barriers and facilitators. intention is established by motivation (attitude, social influence, and self-efficacy), awareness (awareness, knowledge, and perceived risk) and information and predisposing determinants. predisposing factors include baseline characteristics of studied populations and influence awareness, motivation and uptake. information factors include information retrieved via media, social contacts and healthcare workers. simplified i-change model summarizing the studied determinants that could predict vaccination uptake. we used a simplified version of the i-change model applied to vaccination uptake. uptake is shaped by the intention to get vaccinated which is subject to barriers and facilitators. intention is established by motivation (attitude, social influence, and self-efficacy), awareness (awareness, knowledge, and perceived risk) and information and predisposing determinants. predisposing factors include baseline characteristics of studied populations and influence awareness, motivation and uptake. information factors include information retrieved via media, social contacts and healthcare workers. the literature search generated 2227 hits ( figure 2 ). after removing duplicates and excluding articles published before 2010, 1260 articles were available on the topic. these were screened based on title and abstract, resulting in 242 articles that were eligible for full-text assessment. these were divided into the three subgroups (some were included in more than one category): 30 for travellers, 95 for icp, and 122 for hcw. finally, 17, 29, and 44 articles were included in the data analysis for the three groups, respectively. the most common reason for exclusion was that no determinants (other than predisposing factors) were reported. table 1 describes the characteristics and quality of included studies for travellers, icp, and hcw. determinants that play a role in vaccination uptake were retrieved from the articles and summarized in tables 2-4 for travellers, icp, and hcw respectively. the results of the quality assessment are presented in supplementary table s2 . the 17 articles that studied determinants of vaccination uptake among travellers comprised 12 cross-sectional surveys, two pre-and post-travel surveys, and three retrospective studies of which one was based on confirmed cases of vpd (table 1 ). travellers that were studied originated from the usa (6 studies), australia (4 studies), europe (5 studies), or mixed continents (2 studies). sample sizes ranged from 55 to 27,386 and comprised hajj pilgrims in three studies, travellers to africa in two studies and to asia in two studies. other studies had broader inclusion criteria. three studies hajj x x x vfr x x backpackers x vpd influenza x x x x x x x men x x x x x pneu x x x hav x x x x x hbv x x x x x x dtp/tdap x x x x mmr x x x vzv/hzv x x yf x x x je x x x rabies x x x typhoid fever x x x vaccines in general x x determinants predisposing factors age ↓ = ↓ ↓ ↑ = = = ↑ gender: male = = = = = = education level = ↑ ↑ travel purpose: vfr = ↓ = ↓ travel purpose: business ↑ ↓ travel duration = = ↓ = ↓ ↑ internet ‹ ‹ ‹ ‹ ‹ « tv/radio ‹ primary hcw (gp) ‹ ‹ ‹ ‹ « ‹ « « specialist hcw (travel clinic) ‹ ‹ ‹ ‹ ‹ family/friends ‹ ‹ ‹ ‹ ‹ ‹ travel organization « ‹ the following symbols are used: x applicable; = no significant difference; ↑ significant positive association (tested by multivariate analysis); ↓ significant negative association (tested by multivariate analysis); ↑ significant positive association (tested by chi-square, univariate analysis or correlation coefficient); ↓ significant negative association (tested by chi-square, univariate analysis or correlation coefficient); « (double caret pointing upwards) significance was not tested, but determinant was positively linked to vaccination uptake in ≥50% of the population; « (double caret pointing downwards) significance was not tested, but determinant was negatively linked to vaccination uptake in ≥50% of the population; ‹ (caret pointing upwards) significance was not tested, but determinant was positively linked to vaccination uptake in ≥10% of the population; ‹ (caret pointing downwards) significance was not tested, but determinant was negatively linked to vaccination uptake in ≥10% of the population. * determinants were studied in relation to intention to be vaccinated instead of vaccination uptake. the following symbols are used: x applicable; = no significant difference; ↑ significant positive association (tested by multivariate analysis); ↓ significant negative association (tested by multivariate analysis); ↑ significant positive association (tested by chi-square, univariate analysis or correlation coefficient); ↓ significant negative association (tested by chi-square, univariate analysis or correlation coefficient); used: x applicable; = no significant difference; ↑ significant positive association (tested by multivariate analysis); ↓ significant negative association alysis); ↑ significant positive association (tested by chi-square, univariate analysis or correlation coefficient); ↓ significant negative association ariate analysis or correlation coefficient); « (double caret pointing upwards) significance was not tested, but determinant was positively linked to of the population; « (double caret pointing downwards) significance was not tested, but determinant was negatively linked to vaccination uptake ; ‹ (caret pointing upwards) significance was not tested, but determinant was positively linked to vaccination uptake in ≥10% of the population; ‹ s) significance was not tested, but determinant was negatively linked to vaccination uptake in ≥10% of the population. * determinants were studied (double caret pointing upwards) significance was not tested, but determinant was positively linked to vaccination uptake in ≥50% of the population; ↑ significant positive association (tested by multivariate analysis); ↓ significant negative association ve association (tested by chi-square, univariate analysis or correlation coefficient); ↓ significant negative association n coefficient); « (double caret pointing upwards) significance was not tested, but determinant was positively linked to le caret pointing downwards) significance was not tested, but determinant was negatively linked to vaccination uptake significance was not tested, but determinant was positively linked to vaccination uptake in ≥10% of the population; ‹ (double caret pointing downwards) significance was not tested, but determinant was negatively linked to vaccination uptake in ≥50% of the population; ∧ (caret pointing upwards) significance was not tested, but determinant was positively linked to vaccination uptake in ≥10% of the population; ∨ (caret pointing downwards) significance was not tested, but determinant was negatively linked to vaccination uptake in ≥10% of the population. * determinants were studied in relation to intention to be vaccinated instead of vaccination uptake. x internet/social media the following symbols are used: x applicable; = no significant difference; ↑ significant positive association (tested by multivariate analysis); ↓ significant negative association (tested by multivariate analysis); ↑ significant positive association (tested by chi-square, univariate analysis or correlation coefficient); ↓ significant negative association (tested by chi-square, univariate analysis or correlation coefficient); « (double caret pointing upwards) significance was not tested, but determinant was positively linked to vaccination uptake in ≥50% of the population; « (double caret pointing downwards) significance was not tested, but determinant was negatively linked to vaccination uptake in ≥50% of the population; ‹ (caret pointing upwards) significance was not tested, but determinant was positively linked to vaccination uptake in ≥10% of the population; ‹ (caret pointing downwards) significance was not tested, but determinant was negatively linked to vaccination uptake in ≥10% of the population. the following symbols are used: x applicable; = no significant difference; ↑ significant positive association (tested by multivariate analysis); ↓ significant negative association (tested by multivariate analysis); ↑ significant positive association (tested by chi-square, univariate analysis or correlation coefficient); ↓ significant negative association (tested by chi-square, univariate analysis or correlation coefficient); used: x applicable; = no significant difference; ↑ significant positive association (tested by multivariate analysis); ↓ significant negative association alysis); ↑ significant positive association (tested by chi-square, univariate analysis or correlation coefficient); ↓ significant negative association ariate analysis or correlation coefficient); « (double caret pointing upwards) significance was not tested, but determinant was positively linked to of the population; « (double caret pointing downwards) significance was not tested, but determinant was negatively linked to vaccination uptake ; ‹ (caret pointing upwards) significance was not tested, but determinant was positively linked to vaccination uptake in ≥10% of the population; ‹ s) significance was not tested, but determinant was negatively linked to vaccination uptake in ≥10% of the population. * determinants were studied (double caret pointing upwards) significance was not tested, but determinant was positively linked to vaccination uptake in ≥50% of the population; ↑ significant positive association (tested by multivariate analysis); ↓ significant negative association ve association (tested by chi-square, univariate analysis or correlation coefficient); ↓ significant negative association n coefficient); « (double caret pointing upwards) significance was not tested, but determinant was positively linked to le caret pointing downwards) significance was not tested, but determinant was negatively linked to vaccination uptake significance was not tested, but determinant was positively linked to vaccination uptake in ≥10% of the population; ‹ d, but determinant was negatively linked to vaccination uptake in ≥10% of the population. * determinants were studied (double caret pointing downwards) significance was not tested, but determinant was negatively linked to vaccination uptake in ≥50% of the population; ∧ (caret pointing upwards) significance was not tested, but determinant was positively linked to vaccination uptake in ≥10% of the population; ∨ (caret pointing downwards) significance was not tested, but determinant was negativvely linked to vaccination uptake in ≥10% of the population. social media ↓ ↓ tv/radio ↓ evidence-based sources ↑ ↑ ↑ ↑ ↑ collegues ↑ * one scale (movac-flu scale) was used for following determinants: knowledge, attitude and self-efficacy. the following symbols are used: x applicable; = no significant difference; ↑ significant positive association (tested by multivariate analysis); ↓ significant negative association (tested by multivariate analysis); ↑ significant positive association (tested by chi-square, univariate analysis or correlation coefficient); ↓ significant negative association (tested by chi-square, univariate analysis or correlation coefficient); ↓↑ significant association, for one vaccine positive, for the other negative; « (double caret pointing upwards) significance was not tested, but determinant was positively linked to vaccination uptake in ≥50% of the population; « (double caret pointing downwards) significance was not tested, but determinant was negatively linked to vaccination uptake in ≥50% of the population; ‹ (caret pointing upwards) significance was not tested, but determinant was positively linked to vaccination uptake in ≥10% of the population; ‹ (caret pointing downwards) significance was not tested, but determinant was negatively linked to vaccination * one scale (movac-flu scale) was used for following determinants: knowledge, attitude and self-efficacy. the following symbols are used: x applicable; = no significant difference; ↑ significant positive association (tested by multivariate analysis); ↓ significant negative association (tested by multivariate analysis); ↑ significant positive association (tested by chi-square, univariate analysis or correlation coefficient); ↓ significant negative association (tested by chi-square, univariate analysis or correlation coefficient); ↓↑ significant association, for one vaccine positive, for the other negative; x applicable; = no significant difference; ↑ significant positive association (tested by multivariate analysis); ↓ significant negative association is); ↑ significant positive association (tested by chi-square, univariate analysis or correlation coefficient); ↓ significant negative association te analysis or correlation coefficient); « (double caret pointing upwards) significance was not tested, but determinant was positively linked to the population; « (double caret pointing downwards) significance was not tested, but determinant was negatively linked to vaccination uptake (double caret pointing upwards) significance was not tested, but determinant was positively linked to vaccination uptake in ≥50% of the population; ‹ nificant difference; ↑ significant positive association (tested by multivariate analysis); ↓ significant negative association ve association (tested by chi-square, univariate analysis or correlation coefficient); ↓ significant negative association n coefficient); « (double caret pointing upwards) significance was not tested, but determinant was positively linked to le caret pointing downwards) significance was not tested, but determinant was negatively linked to vaccination uptake significance was not tested, but determinant was positively linked to vaccination uptake in ≥10% of the population; ‹ (double caret pointing downwards) significance was not tested, but determinant was negatively linked to vaccination uptake in ≥50% of the population; ∧ (caret pointing upwards) significance was not tested, but determinant was positively linked to vaccination uptake in ≥10% of the population; ∨ (caret pointing downwards) significance was not tested, but determinant was negatively linked to vaccination uptake in ≥10% of the population. prisk = perceived risk. prisk of infection (s/p): s = self; p = patient. the following abbreviations are used (in alphabetical order): cd = crohn's disease; dtp = diphtheria, tetanus, poliomyelitis; gp = general practitioner; hav = hepatitis a virus; hbv = hepatitis b virus; hcw = healthcare workers; hiv = human immunodefiency virus; hsct = hematological stem cell transplantation; hzv = herpes zoster virus; ibd = inflammatory bowel disease; is = immunosuppressants; je = japanese encephalitis; men = meningococcal disease; mmr = measles, mumps, rubella; pneu = pneumococcal disease; tdap = tetanus, diphtheria, acellular pertussis; sot = solid organ transplantation; vfr = travellers visiting friends and relatives. vzv = varicella zoster virus, yf = yellow fever. the 17 articles that studied determinants of vaccination uptake among travellers comprised 12 cross-sectional surveys, two pre-and post-travel surveys, and three retrospective studies of which one was based on confirmed cases of vpd (table 1 ). travellers that were studied originated from the usa (6 studies), australia (4 studies), europe (5 studies), or mixed continents (2 studies). sample sizes ranged from 55 to 27,386 and comprised hajj pilgrims in three studies, travellers to africa in two studies and to asia in two studies. other studies had broader inclusion criteria. three studies used kap (knowledge-attitude-practices) surveys and one study mentioned a health behavioural model (theory of planned behaviour) as theoretical background for their study. ten articles studied baseline characteristics of travellers that could be associated with vaccination uptake ( table 2 ). the vaccinations that were studied were diverse, most papers discussed vaccinations for influenza (n = 7), hepatitis b virus (hbv) (n = 6), hepatitis a virus (hav) (n = 5) and meningococcal disease (n = 5). regarding age, three papers reported that younger people had a higher uptake [18, 20, 24] . however, for influenza vaccination this was the opposite: older travellers were more likely to be vaccinated for seasonal influenza [27, 32] . gender was not a significant predictor of vaccination uptake in any of the studies. education level was studied by three papers [18, 27, 31] . two found this determinant to be positively associated with (intention to) obtaining recommended vaccinations [28, 31] . seven studies reported travel purpose in relation to vaccination uptake, but the results were diverse. one study concluded vaccination uptake was highest if the reason of travelling was business or backpacking [20] . however, work-related travel was associated with lower uptake in another study (or = 0.39, (0.17-0.92)) [27] . travellers visiting friends and relatives (vfr) had a lower uptake in two studies [24, 29] , but two other studies found no association [20, 25] . six papers studied the relation between travel duration and vaccination uptake. two studies showed that uptake was significantly lower when people travelled longer [24, 28] , while one found that it was higher (for rabies only) [29] and three studies found no difference [19, 20, 27] . no clear relationship between information sources and vaccination uptake was reported. however, eight studies reported a role for the gp, of which three said that the gp was very influential [22, 29, 30, 32] . of all the cognitive determinants studied, perceived risk of infection was most frequently described in relation to vaccination uptake (n = 10). only one study found a significant positive relation (or 1.74 (95% ci 1.14-2.62)) [16] , and another five reported this factor to play a role in the majority of the study population. although not often tested for significance, "not feeling at risk of the disease" was a common explanation of a lot of travellers for not receiving the recommended vaccinations. perceived risk of vaccination was sparsely discussed (n = 4). social influence, which comprises mostly trust and recommendations of healthcare providers in this selection of studies, was reported in seven papers and was recognised as important by the majority of the study population in four papers. attitude was described in six papers, and was not found to be significant in two of them [19, 31] ; reliance on natural immunity was mentioned three times as a reason to reject vaccination [17, 23, 30] . awareness was also discussed in six papers; although it was not tested for significance, 13-73% mentioned unawareness of the availability of the vaccination (or unawareness of the recommendation of the vaccination) as an important reason for non-uptake [17, 18, [20] [21] [22] 30] . five studies reported on knowledge of vpd; two found a significant positive relation between knowledge and vaccination uptake [20, 26] , one found no relation [19] . reported barriers could be classified in costs and lack of time. costs were the most described; however, it played a modest role in explaining non-uptake and differed per vaccination. for instance, for influenza vaccination uptake costs were mentioned to play a role in less than 7% of travellers, while for hbv (12%), japanese encephalitis (35%) and pneumococcal vaccination (38%) concerns about costs were much higher. in two papers lack of time was given as part of the explanation of non-uptake in more than 10% of the study population [17, 22] . one paper described that 3-24% of travellers require a reminder to complete their vaccination series [22] . twenty-nine articles concerning icp were included. most of these studies were cross-sectional (n = 23), but four were prospective (with a follow-up moment) and two retrospective ( table 1) . studies were performed among european (n = 23), american (n = 3) and canadian (n = 3) populations. sixteen studies involved patients with auto-immune diseases, of which four studies focussed completely on patients with inflammatory bowel disease. the vaccination uptake of hiv patients was studied in three papers. four papers studied populations with solid tumours, six papers studied patients who received haematological stem cell transplantation (hsct) and three papers investigated patients who received a solid organ transplantation (sot). almost all papers addressed the influenza vaccination uptake (n = 25) and many also included the uptake of pneumococcal vaccinations (n = 13). influenza vaccination rates varied from 6-79% and pneumococcal vaccination rates from 2-54%. lowest rates were reported in polish inflammatory bowel disease (ibd) patients [60] and highest in american rheumatic patients [55] . in icp, health behaviour models were cited slightly more than in the travellers population. two studies were based on the (hbm) and another three studies used kap surveys. most studies (17 out of 24 that studied age) found a positive association between age and vaccination uptake (table 3) . especially for influenza vaccination, older patients tend to be more compliant with vaccination guidelines in the studied year. only in one study a negative association was found (or 0.02, 95% ci (0.01-0.57)) [46] . most studies report that gender and education level are not significant predictors of vaccination uptake in icp, with a few exceptions. three studies showed in a multivariate analysis that males had a higher uptake. two studies showed a negative association between uptake and education level, while one showed a positive association. in five studies, the use of strong immunosuppressive medication was positively associated with vaccination uptake, whereas in two studies the association was negative and in three there was no association. generally, icp with comorbidities in their medical history tend to have a higher uptake in four [38, 39, 42, 54] out of seven studies. one study reported a negative association [42] and two found no significant difference [33, 52] . all five papers that included vaccination history (for the same or another vaccination), concluded that there was a positive association between vaccination uptake in the past and current uptake [34, 43, 46, 47, 52] . thirteen studies investigated where icp retrieve their information from. in general, gathering information from online media sources was somewhat associated with a lower vaccination uptake, while receiving information from hcw resulted in a higher uptake [35, 41] . perceived risk of vaccination was the most frequently mentioned cognitive determinant, being discussed in 21 of the 29 articles. in all three papers that tested for significance, a negative correlation with vaccination uptake was found, meaning that a higher perceived risk of a vaccine results in a lower uptake. but also that a lower perceived risk, reflected for example by trust in the effectivity of this specific vaccine, increases the uptake. fear for side-effects or deterioration of their disease caused by the vaccination were mentioned often. another concern that was often expressed was the doubt of effectivity of vaccination, due to either the immunogenicity of the vaccine or due to the compromised state of the patients' immune system. distrust was reported more often for influenza than for other vaccinations [55] . awareness of either the availability of or the indication for a vaccination was also widely discussed (n = 17). while only found to be significantly correlated twice, this determinant played a role in the majority of the study population in seven papers. because icp often mention vaccination not being proposed as a reason for non-uptake, this determinant is related to the information factors, knowledge, and hcw recommendation. attitude, covering the attitude to vaccinations in general, was mentioned in 14 studies and was found to be positively correlated twice in multivariate analysis. the effect of a favourable attitude to vaccinations in general was larger on uptake of influenza (adjusted odds ratio (aor) 3.4 (95% confidence interval (ci) 1.2-9.5)) than on uptake of pneumococcal vaccination (aor 1.7 [95% ci 0.8-3.5]) [44] . perceived risk of infection was mentioned equally often as attitude (n = 14) and was also positively associated with uptake, in two of the four studies that tested for significance [46, 59] . although knowledge was only addressed in four papers, in two out of the three articles that tested for significance a positive correlation was found. recommendation of an hcw was studied in 12 out of the 29 papers and a significant correlation was found in all eight papers that performed statistical analysis. in addition, a frequently reported reason for not being vaccinated was that vaccination was not offered or recommended, which we included under awareness. self-efficacy was reported in two papers. one reported that more than 10% of unvaccinated icp were unsure of how to arrange to receive the vaccines [56] , while another reported that patients who find it easier to attend a gp for vaccination, have a higher intention to get vaccinated (p < 0.001) [46] . regarding intention to behaviour, one high-quality study expressed that 80% of their ibd study population expressed to be willing to receive all of the recommended vaccinations, while only 9% had ever received a pneumococcal vaccination and only 28% was vaccinated against influenza at the time of participation in the study [58] . in another study with 17% influenza and 4% pneumococcal vaccination uptake, the intention to be vaccinated next year was also high and not significantly different between the vaccinated (89%) and unvaccinated group (80%) [59] . cost was only mentioned as a barrier in one paper that found a significant negative correlation with uptake [36] . lack of time (n = 2) and the inconvenience of another appointment (n = 4) were more often given as reasons for declining vaccination. in hcw, influenza vaccination uptake is most widely studied. in 35 articles out of the 44, seasonal influenza vaccination was the only vaccine studied, with uptake varying between 9% [63] to 97% (mandatory policy) [96] . most studies were conducted in italy (n = 8), followed by france (n = 5) and the usa (n = 5). all but one were designed as cross-sectional surveys, with sample sizes ranging from 77 [76] to 32,808 [91] . seven studies mentioned the use of a theoretical model for their study, which includes the hbm [88] , the tpb [89] , the risk perception attitude framework [93] , the triandis model of interpersonal behaviour [81] , the cognitive model of empowerment [99] or mixtures of different models [64, 79] (table 1 ). thirty-six articles studied at least one predisposing factor in relation to vaccination uptake (table 4) . of the 30 articles that studied age, 22 found that older healthcare workers had a significantly higher uptake. on the other hand, in the case of hepatitis b [84, 95] and measles [78, 82] , younger hcw's had higher compliance. in the 27 papers that studied gender, being male was associated with higher vaccination uptake in 13 studies. five papers mentioned a significantly higher uptake in women, one for rubella only [97] , and another for hepatitis b only [82] . occupation was studied in relation to vaccination uptake in 18 articles. sixteen papers showed that physicians had a significantly higher uptake than other hcw. this also complies with the significant positive association between education level and uptake that was found in five papers. presence of a chronic disease resulted in significantly higher uptake in seven studies. in three other studies investigating this factor, no association was found. having children at home was studied in nine papers, but six found no significant role for this factor in vaccination uptake. good vaccine compliance in the past turned out to be an excellent predictor of uptake in all 11 studies investigating this factor. the role of information sources in vaccination uptake was studied in six articles. when information was gathered from evidence-based sources, uptake was significantly higher in all five studies that investigated this source. on the other hand, uptake was lower when information was retrieved from social media, television, or radio [63, 92] . only one study found that gaining information from colleagues was associated with a higher uptake [78] . perceived risk was the most frequently described determinant in hcws. more specifically, perceived personal risk of infection reflects the perceived risk to contract the vpd, including the perceived susceptibility to get infected and the perceived severity of the disease if contracted. in 33 out of 35 papers mentioning perceived risk of infection, a significant positive relation was found between this determinant and vaccination uptake (n = 13), or these reasons were mentioned in a considerable part of the study group (n = 20). furthermore, in 18 papers a high perceived risk to infect patients was given as a reason for vaccination uptake. perceived risk (vs. benefit) of vaccination was mentioned in 34 papers. fifteen studies reported a significant negative relation between perceived risk and uptake, indicating that high perceived risk or low perceived benefit of the vaccination resulted in lower uptake. additionally, five papers mentioned that this determinant played a role in the majority of the study population. adequate knowledge of recommendations, effectiveness, and side-effects of vaccinations was significantly positively associated with uptake in 11 papers; in four studies, no significant association was found. attitude towards vaccination was studied in 22 articles. in half of them, a significant positive association with vaccination uptake was found. social influence (encouragement of colleagues, managers, family) was analysed in almost half of the studies (n = 15). in only one study no association was found [66] , but the others showed either a significant (n = 8) or considerable (n = 6) positive relation with vaccination uptake. specific for hcw are the social arguments 'i got vaccinated because it's my duty as an hcw' or 'as an hcw, i have a role in the prevention of epidemics/spread of diseases', that we collected under the term 'professional norms'. this determinant was positively associated with uptake in all 15 studies focusing on this factor; in seven out of 11 studies that tested for significance, this factor remained a strong predictor for uptake in multivariate analysis. in comparison with the previous determinants, barriers and facilitators are relatively less studied. of the barriers, time-related factors were mentioned most frequently and played a considerable role (>10%) in hindering uptake in seven studies. costs turned out to be no barrier. the fact that the vaccines were free of charge even appeared to be a reason for uptake in two studies [62, 67] . on the other hand, facilitators stimulating uptake were getting a reminder (n = 3), convenient time/place of distribution (n = 4), and getting a reward (n = 3). however, in none of the studies were the potential rewards specified. our review of the currently available literature shows that there are clear differences in determinants that play a role in vaccination uptake in travellers, icp, and hcw. for travellers, low perceived risk of infection and low awareness of vaccination recommendations are most accountable for low uptake. for icp, awareness of the indication of vaccination plays an important role, together with receiving vaccination recommendations from their treating physician. icp have a high perceived risk of vaccination, due to not only fear for general side-effects but also concerns about potential consequences for their illness. for hcw, perceived risk of (the severity of) infection for themselves and for their patients together with perceived benefits of vaccination contribute most to their vaccination behaviour. regarding predisposing factors, there is a clear positive relationship between age and influenza vaccination uptake in all risk groups. this could be explained by the additional indication older people have for influenza vaccination. however, for other vaccinations, this relationship is either inverted or non-existent. higher vaccination uptake was seen in males in hcw and icp, which could be associated with the fact that females worry more about vaccine safety and efficacy than males [107] . indeed, more side-effects are reported by females, while on the other hand, from a biological perspective, females typically mount higher antibody responses [107] . although we did not find a clear relationship between education level and vaccination uptake in the risk groups, in hcw the uptake was markedly higher in physicians compared to other hcw. overall, vaccination history seems to be an excellent universal predictor of future vaccination uptake, probably due to unaltered cognitive determinants. regarding cognitive determinants, the greatest diversity between risk groups was found in awareness. in icp, almost two-thirds of the studies mentioned limited awareness, compared to one-third in travellers and none in hcw. with their education and occupation, it seems quite obvious that hcw are aware of the opportunities and indications for vaccinations. the fact that icp seem less aware than travellers might have to do with travellers taking an active decision to go abroad realizing that they have to prepare themselves, while patients get passively diagnosed with a disease, and are more dependant of the hcw for information provision. in all groups, hcw as a source of information has a positive effect on uptake. the strong relationship between hcw recommendations and vaccination uptake in icp (reaching odds ratios up to 53 [52] and 187 [44] ), underline the importance of positive attitudes towards vaccination in hcw themselves [100, 108] . in general, knowledge has a positive influence on uptake in all risk groups. however, since several studies showed no relation between knowledge and uptake [19, 35, 62, 66, 71, 95] , improving education alone will probably not be sufficient to increase uptake. in all groups, the perceived susceptibility and severity of diseases on one hand and the perceived effectiveness and risks of vaccinations on the other hand are important determinants predicting uptake. especially icp and hcw express concerns about the safety and effectiveness of vaccines particularly for influenza vaccination [38, 44] . and although the effectiveness of influenza vaccination varies with the coverage of circulating strains each year, another part of the perceived lack of effectiveness could also be explained by the lack of protection for other common cold viruses that can cause influenza-like symptoms [109] . travelers seem to have low risk perceptions for the diseases they could be vaccinated for as well as for the potential negative effects of vaccination. despite the high morbidity and mortality of some vpd such as yellow fever, hepatitis b, and influenza, in all risk groups, some participants stated they preferred natural immunization or were against vaccinations in general. remarkably, attitudes differ for specific vaccinations, for instance, people tend to have a more positive attitude towards pneumococcal vaccination in comparison to the seasonal influenza vaccination [55] . interestingly, the mistrust of icp and hcw towards the vaccinations produced by the pharmaceutical industry seems disproportionate to therapeutics manufactured by the same pharmaceutical companies [40, 50, 72, 78] . here, the difference between prevention and treatment might play a role, where the latter provides a more direct and visible effect. another possible reason for the negative general attitude towards vaccination, also described in decision making for childhood vaccinations [110] , is the increasing tendency for self-empowerment towards personal health decisions. in this view, individuals stand up against imposed policies and want to make their own decisions, which could also be judged by peers as independent and smart decision making [110, 111] . at the same time, sources that are being used to make personal health decisions, such as the internet, contain a lot of negative stories [112] . practical barriers and facilitators play a limited role in vaccination uptake compared to the other determinants. in all three groups, a reminder is an important facilitator and (lack of) time an important barrier. especially for hcw, this factor is interesting. physicians report this factor most frequently [73] . they do not only experience lack of time to get vaccinated, they also feel that lack of time impedes their duty to recommend vaccinations to their patients [113] . again, as hcw recommendations are strongly positively associated with uptake, not only in the other risk groups, but also for hcw themselves (by colleagues for example) [66, 80] , removing this barrier can result in achieving optimal care for all groups. only 16 of the 90 articles that were analysed in this review were based on a health behaviour model. many of those found determinants which contributed to vaccination uptake to a greater or lesser extent [46, 64, 79, 93, 99] . interventions that focus on a single determinant, such as knowledge, repeatedly proved to be ineffective in the past [66] , while multifactorial cognitive intervention strategies are effective to improve uptake [114, 115] . therefore, all determinants that play a role have to be taken into account. predisposing factors could be used to target specific subgroups and personalize uptake strategies [93] . facilitators and barriers could be added or taken away to increase vaccination uptake. but, most importantly, interventions need to address cognitive determinants. interventions that increase awareness and risk perception of infectious diseases are more effective than those decreasing risk perceptions of vaccination by providing scientific information [116] . social norms can be influenced in the case of hierarchical relationships, for instance, the employer will have an effect on the vaccination decision of hcw and hcw will impact icp's decisions. therefore, multifactorial interventions are needed that address the most important cognitive determinants. as these include awareness and risk perceptions, reminders and incidence data could help. reminders for travellers could be disseminated in general media before holidays, while for icp patient associations and hcw could play a role. to improve risk perceptions for the infections, cases of vaccine-preventable diseases should be made public. to decrease risk perceptions of negative effects of vaccinations (e.g., adverse events) new studies should compare the number of influenza-like illnesses in vaccinated and non-vaccinated groups. furthermore, social norms can be included by making the decisions of vaccination uptake public. for example, in hcw trials have been implemented to test the effects of providing a pin that vaccinated hcw may wear that is saying "deliberately vaccinated", which could affect both colleagues and patients [117] . vaccination decisions of travellers and icp are less well studied than those of hcw. additionally, data on uptake of vaccinations other than influenza are limited. as the available data show large differences in determinants predicting uptake of influenza versus other vaccinations, further studies are required regarding the uptake of recommended vaccinations for diseases other than influenza. reaching a more comprehensive understanding of vaccination uptake in different risk groups for the different vaccinations that are indicated, interventions can be developed based on evidence. moreover, this understanding could help with the implementation of new vaccines for certain risk groups, for instance when a novel sars-cov-2 vaccine will be recommended for hcw. a number of limitations have to be taken into account when interpreting the results of this review. first, articles were only included if they discussed any cognitive determinants that were possibly related to vaccination uptake. this resulted in the exclusion of papers that looked only, although thoroughly, into predisposing factors. secondly, there was a high level of heterogeneity in the determinants reported, as studies used various health behaviour models as a framework for their studies, and many did not even use a model but just reported results of questionnaires with either open-ended or multiple-choice questions. furthermore, the influence of determinants on vaccination uptake was measured with different statistical analyses, which also contributed to the high heterogeneity of the data. therefore, we choose to report the significance and direction of the association, instead of the magnitude. in addition, we choose to compare three different risk groups that we think are important, thereby we could not discuss all determinants in depth. finally, included studies were based on self-reported vaccination behaviour. therefore, we have to take into account a certain level of social desirability and recall bias. to our knowledge, this is the first review that provides a comprehensive overview of health behavioural determinants explaining vaccination uptake in three different risk groups, namely travellers, icp, and hcw. we showed that there is 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