Archives of Academic Emergency Medicine. 2021; 9(1): e56 REV I EW ART I C L E Facemask and Respirator in Reducing the Spread of Respi- ratory Viruses; a Systematic Review Negin Shaterian1, Fatemeh Abdi2,3∗, Zahra Atarodi Kashani4, Negar Shaterian5, Mohammad Darvishmotevalli6 1. Student Research Committee, School of Nursing & Midwifery, Shahid Beheshti University of Medical Sciences, Tehran, Iran. 2. School of Nursing and Midwifery, Alborz University of Medical Sciences, Karaj, Iran. 3. Non-Communicable Diseases Research Center, Alborz University of Medical Sciences, Karaj, Iran. 4. Department Midwifery, Iranshahr University of medical sciences, Iranshahr, Iran. 5. Student Research Committee, Jahrom University of Medical Sciences, Jahrom, Iran. 6. Research Center for Health, Safety and Environment , Alborz University of Medical Sciences, Karaj, Iran. Received: May 2021; Accepted: June 2021; Published online: 16 August 2021 Abstract: Introduction:Respiratory viruses spread fast, and some manners have been recommended for reducing the spread of these viruses, including the use of a facemask or respirator, maintaining hand hygiene, and perfoming social distancing. This systematic review aimed to assess the impact of facemasks and respirators on reducing the spread of respiratory viruses. Methods: We conducted a systematic review using MeSH terms, and reported findings according to PRISMA. PubMed, Embase, Cochrane Library, Scopus, ProQuest, Web of Science(WoS), and Google Scholar were searched for articles published between 2009 and 2020. Two independent reviewers determined whether the studies met inclusion criteria. The risk of bias of studies was assessed using Newcastle- Ottawa (NOS) and Consolidated Standards of Reporting Trials (CONSORT). Results: A total of 1505 articles were initially retrieved and 10 were finally included in our analysis (sample size: 3065). 96.8% of non-infected par- ticipants used facemask or respirator in contact with people infected with a respiratory virus, facemask and respirator have a significant effect on reducing the spread of respiratory viruses. Conclusion: Evidence support that using a facemask or respirator can reduce the spread of all types of respiratory viruses; therefore, this result can be generalized to the present pandemic of a respiratory virus (SARS-COV-2) and it is recommended to use a facemask or respirator for reducing the spread of this respiratory virus. Keywords: Masks; respiratory protective devices; respiratory tract infections; virus diseases; N95 respirators Cite this article as: Shaterian N, Abdi F, Atarodi Kashani Z, Shaterian N, Darvishmotevalli M. Facemask and Respirator in Reducing the Spread of Respiratory Viruses; a Systematic Review. Arch Acad Emerg Med. 2021; 9(1): e56. https://doi.org/10.22037/aaem.v9i1.1286. 1. Introduction In recent decades, humans have been threatened by a vari- ety of viruses that lead to acute respiratory infections affect- ing human life and human societies, sometimes leading to death. There are several routes of respiratory virus transmis- sion: contact, droplet, and aerosol. Respiratory viral infec- tions cause a wide range of overlapping symptoms, known as acute respiratory illness (ARI) or, usually (more commonly) ∗Corresponding Author: Fatemeh Abdi; Alborz University of Medical Sciences, Taleghani Boulevard, Taleghani Square, Karaj, Iran. Email: abdi@sbmu.ac.ir, Tel:+9826 34197000, ORCID: https://orcid.org/0000-0001- 8338-166X. “the common cold” as a whole, which is chiefly mild but may cause severe illness and death (1). To protect themselves against such viruses, humans have offered a variety of strate- gies, from wearing facemasks and home quarantine to pro- ducing drugs and making the body resistant to such particles using appropriate vaccines. When specific vaccines or disin- fection treatments are not available, the use of non-drug in- terventions, such as wearing respiratory personal protective equipment (RPPE), is important for protecting and reducing the occupational risk of health care workers (HCWs) against respiratory infections (2). Common types of PPE include surgical masks and respira- tors. It should be noted that surgical masks are loose and disposable and create a physical barrier between the wear- This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem N. Shaterian et al. 2 ers’ mouth and nose and environmental contaminants (large respiratory droplets or sprays of blood and body fluids). They are not designed to filter out small airborne particles and have very different level of protection (3, 4). In this regard, the results of some studies have shown that daily use of surgi- cal masks in all areas of the hospital is important in reducing swine flu infection, such measures at least prevent touching the mucous membranes of the nose and mouth with the fin- gers and such unconscious behaviors are less common (5, 6). These masks should be replaced as soon as they get wet or at least every four hours (3). In contrast, n95 respirators or their European equivalent, FFP2-3 prevent the penetration of at least 95% of aerosols less than 5 mm. But due to resis- tance to respiration and heat their long-term use is intolera- ble for HCWs (4). They should be worn for less than 8 hours during the day and should not be reused if they get wet (3). Besides, the equipment needs to fit completely on the face. It is very difficult to use this equipment in people with facial hair or beard and children, and is not recommended for the elderly, claustrophobic, and people with lung disease. Pow- ered air-purifying respirators (PAPRs) have blowers that pro- vide positive pressure airflow through the filter. They do not need to fully fit, and they protect the head and neck contigu- ously. One of its disadvantages is being the most expensive PPE. The world is currently suffering from a pandemic (7), caused by a virus now known as Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) (named by the International Committee on Taxonomy of Viruses (ICTV )), Which has a phylogenetic similarity to SARS-CoV and its resulting disease is called COVID-19 (8, 9). Recommendations for the use of surgical masks during the present coronavirus disease pan- demic include: people with suspected or confirmed respira- tory infection COVID-19 symptoms; people in contact with HCWs or first-aid workers, and HCWs in contact with peo- ple with symptoms of respiratory infection (3). The present study aims to assess the effect of wearing a facemask on the reduction of incidence and prevention of infection with res- piratory viruses such as SARS-CoV-2. 2. Methods This systematic review is reported based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines (10). 2.1. Search strategy In this systematic review, Google Scholar, PubMed, Embase, Cochrane Library, Scopus, ProQuest, and Web of Science (WoS) were searched for articles published between 2009 and 2020. Boolean operators such as "AND" and "OR" were used to make different combinations for search (11). In addition, we searched using the following terms: 1–"facemask" [Mesh] OR "facemasks" [Mesh] OR "mask" [Mesh] OR “N95 Respirator” [Mesh] OR “Respirator, N95” [Mesh] OR “N95 Face Masks” [Mesh] OR “Face Mask, N95” [Mesh] OR “Mask, N95 Face” [Mesh] OR “N95 Face Mask” [Mesh] OR “N95 Masks” [Mesh] OR “Mask, N95” [Mesh] OR “N95 Mask” [Mesh] OR “N95 Filtering Facepiece Respirators” [Mesh] OR “N95 FFRs” [Mesh] OR “N95 FFR” [Mesh] 2-"respirators"[Mesh] OR"Device, Respiratory Protec- tive" [Mesh] OR "Protective Device, Respiratory" [Mesh] OR "Respirators, Industrial"[Mesh] OR "Respirators, Air- Purifying"[Mesh] 3-"respiratory virus"[Mesh] OR " Severe Acute Respiratory Syndrome Virus" [Mesh] OR "SARS-Related Coronavirus" [Mesh] OR "SARS-CoV"[Mesh] "SARS Coronavirus"[Mesh] OR "SARS-Associated Coronavirus"[Mesh] OR "Coronavirus, SARS-Associated"[Mesh] OR "SARS Associated Coron- avirus"[Mesh] 4-#1 AND #2 AND #3 2.2. Type of studies All studies published between 2009 and 2020, which were conducted to assess the effect of facemask on preventing the of spread respiratory viruses and reported the number or per- centage of participants using a facemask and getting or not getting infected with a respiratory virus, were included in the study. Publications such as reviews, letters, comments, and case reports and studies that were conducted just for com- paring different types of facemasks, or evaluated people with a tissue graft, or their sample size was not clear were excluded from the study. There were no language restrictions for using and entering articles in this study. If the language used in an article was not Persian or English, we asked a translator to translate the article. 2.3. Types of participants The studies were selected if their participants were: -people in contact with those infected with respiratory viruses - people who were members of specific groups such as health- care personnel, emergency department and general ward staff, public health workers, Hajj pilgrims 2.4. Types of interventions The studies were reviewed if: - participants used PPE -measured the effect of facemask or PPE on preventing trans- mission of respiratory viruses 2.5. Type of outcome measure All studies measured the number and percentage of partici- pants who used facemask, PPE, vaccine, and distance or did not use them and were infected after being in contact with a This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem 3 Archives of Academic Emergency Medicine. 2021; 9(1): e56 person infected with respiratory viruses. 2.6. Study selection The title and abstract of all studies retrieved during the elec- tronic and manual follow-up search process were assessed based on the inclusion criteria. The full texts of relevant pa- pers were examined based on the mentioned criteria. 2.7. Quality assessment In this study, the quality of Cohort and Cross-Sectional stud- ies was assessed according to the Newcastle-Ottawa scale (NOS) (12); and the quality of Controlled-Trial studies was assessed based on CONSORT. A maximum of ten stars was given to each study based on the NOS. A maximum of five stars was given to selection (including sample size, non- respondents, and ascertainment of the exposure). A maxi- mum of two stars was given to comparability (including the study control for the most important factor). A maximum of three stars was given to outcome (including assessment of the outcome and statistical test). Studies of high-quality score nine or ten stars, studies with a score of seven or eight stars were considered to be of medium quality, and stud- ies scoring less than six stars were considered to be of low quality (13). The CONSORT checklist was also used to report the standard clinical trial studies. This checklist contains 24 questions and a score of 0 or 1 is given to every question. If a study scored above 15, it was included in the study and thoe scoring 15 and below were excluded (14). The quality score for each article is shown in Table 1. 2.8. Data extraction Two investigators independently searched for relevant scien- tific publications, carried out validity assessments, and re- solved any disagreements by consulting a third investigator (15). Data were collected as follows: 1. Research information (reference, type of study, location, and sample size (Male, Female)) 2. Characteristics of the participants (population, and age) 3. Intervention and comparison of the details (type of viruses, type of contact with an infected person, PPE type, facemask type) 4. Outcome measures (number of PPE types, number of face- mask types, infected participants using facemask, distance, time of contact with person, time of using facemask, and vac- cinated people) 2.9. Statistical analysis We calculated the number and percentage of infected and non-infected people in all included studies and reported them in tables. 3. Results The systematic search in the databases identified 1505 ar- ticles. After reviewing their titles and abstracts, 753 dupli- cate articles, 654 records with undesirable study types, and 88 irrelevant articles were removed. Finally, 10 articles (Sam- ple Size=3065) were included in the systematic review. The flowchart of studies included in this review is shown in Fig- ure 1. The characteristics of included studies are presented in Table 1 and their main findings are shown in other tables. The most frequent places where the studies were conducted were California (16, 17), Korea (18, 19), Saudi Arabia (20, 21), Thailand (22), Germany (23), Australia (24), Sydney (25), and New South Wales (25), respectively. 3.1. Factors examined in the studies The factors presented in table one include the author’s name, study design, type of population, sample size, age, result, and quality score. Table two includes type of virus, type of con- tact with an infected person, PPE type, facemask type, and infected participants who used masks after contact with the patient. 3.2. Type of virus, contact, PPE, facemask, and the number of infected people who used a face- mask Type of Virus The types of virus assessed in this systematic review included SARS-CoV-2 (16), MERS (18), MERS-CoV (19, 20, 22), Rhi- novirus (21, 24, 25), Influenza A viruses (H1N1) (17, 21, 23- 25), Influenza B viruses (21, 23-25), Parainfluenza 1,2 and 3 viruses (21, 24), Enteroviruses (21), Adenoviruses (24, 25), Human metapneumoviruses (24, 25), Respiratory syncytial viruses A or B (25), Coronaviruses (24, 25), Picornaviruses (25), and Enteroviruses (25). 3.3. Type of Contact The type of contact with an infected person was assessed in nine articles and varied in different studies. Generally, the contact was between health care workers and infected per- sons (16, 17, 20, 22, 24), emergency department and general ward (18), public health workers (19), Hajj pilgrims (21), and household contact (23, 25), contact with aerosol, and skin- to-skin contact. 3.4. PPE Type The PPE type was mentioned in all assessed studies. PPE types in the studies included gloves (16-20, 22), kind/various types of facemask (16-25), N95 respirator (17, 18, 20), gown (17, 20, 22), face shield, eye protection (20, 22), and cap (22). This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem N. Shaterian et al. 4 3.5. Type of Facemask The type of facemask was mentioned in nine studies and the number of participants who wore each type of facemask was mentioned in seven studies. Surgical masks (18, 19, 21, 23, 25) were used by 18.8%, N95 respirators (17-20, 22, 24) by 34%, Medical masks (20) by 16.1%, and P2 masks (25) by 3% of participants. 3.6. The number of infected people who used a facemask or N95 respirator Generally, 3.2% of participants who wore a facemask became infected with the respiratory virus through contact with an infected person. In studies that all participants wore surgical masks (18, 19, 21, 23, 25), 0.3% of them became infected. In studies that all participants wore N95 respirators (17-20, 22, 24), 1.4% became infected. 0.2% of participants who wore N95 respirators and surgical masks became infected (18, 19). 1.7% of participants who wore N95 respirators and medical masks became infected (20). 0.3% of participants who wore N95 respirators and other facemasks became infected (17) and 0.5% of participants who wore P2 masks and surgical masks became infected (25). Also, some studies did not men- tion the effect of each facemask on preventing virus spread and the percentage of using each type of facemask so it was not possible to draw a precise conclusion about the quality and effectiveness of each type of facemask based on the men- tioned statistics. 3.7. Distance and time of contact Distance between people and the duration of contact with an infected person was mentioned in five studies (16, 19-22). We could not assess the effect of distance and duration of contact on preventing the spread of virus because these studies did not mention the count of the infected participants based on distance and duration of contact. 3.8. Duration of using a facemask and vacci- nated The duration of facemask use and the number of vaccinated people were evaluated in five studies (17, 20, 23-25). How- ever, these studies did not mention the effect of vaccination and duration of facemask use on prevention of virus infec- tion. 4. Discussion The results of the present study showed that using facemask or respirators has a preventive effect on the spread of respi- ratory viruses including SARS-CoV-2, MERS-CoV, Rhinovirus, Influenza A virus (H1N1), Influenza B viruses, Parain- fluenza 1,2 and 3 viruses, Enteroviruses, Adenoviruses, Hu- man metapneumoviruses, Respiratory syncytial viruses A/B, Coronaviruses, Picornaviruses, and Enteroviruses. Moreover, the percentage of transmission of respiratory viruses in peo- ple who wore any type of facemask or N95, respectively, was 0.3% in the surgical mask group, 1.4% in the N95 respirators group, 0.2% in N95 respirators and surgical mask group, 1.7% in N95 respirators and medical mask group, 0.3% in N95 res- pirators and another facemask group, and 0.5% in P2 masks and surgical mask group. In COVID-19 disease pandemic, due to the lack of access to appropriate antiviral medications and the lack of a suit- able vaccine, infection control was the most important way to control it (26). Therefore, many countries performed non-drug interventions and early control strategies that in- cluded the use of facemasks and double key actions such as hand hygiene and temporary closure of schools and of- fices as recommended by the international scientific com- munities (25). SARS-CoV-2 transfer is mainly through direct transfer of droplets by sneezing and coughing and contact; also, airborne transfer is possible via aerosol-generating pro- cedures (AGPs) (24, 27, 28). Moreover, it has been shown that large droplets could accelerate the transfer of fomite and suspended in the air (28). Besides, these large droplets can move up to two meters or eight meters (28). In this regard, Liu et al. showed that a high concentration of virus is in the air sample of the patient’s toilet and in the environment in which HCWs their PPE (29). Hence, virus-infected particles are more likely to be suspended in the air in places where the airflow is turbulent and patients with or without symptoms or in the pre-symptom phase of COVID-19 have many refer- rals (30). And health care workers are more likely to become infected (46). In this regard, the rate of Influenza virus trans- mission between HCWs in the H1N1 pandemic were 14%, yet 67% of them did not have any signs (31). Besides, most positive cases were between outpatient and Ancillary HCWs and HCWs who used surgical masks or N95 respirators were seronegative (31). This indicates that they’d not use PPE such as facemasks (31). Moreover, Ki et al. showed that emer- gency department staff had more exposure to respiratory in- fections MERS disease compared to the internal department staff (In terms of time, the medical staff of the emergency de- partment spent more time with the index patient than those working in the internal department, eight hours versus one hour). However, the rate of being stricken with disease was 3% vs 16.7%, respectively, because 93% of emergency depart- ment staff used surgical masks and 95% of them used hand wash but only 8% of the general department staff used surgi- cal masks (32). It should be noted that in studies, the proportion of infected HCWs among the confirmed cases of Coronavirus disease- 2019 is 10% in Italy, 20% in Spain, and 40% in the United States (33). Infected HCWs can be a source of infection for other HCWs and patients (4). Therefore, the protection of This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem 5 Archives of Academic Emergency Medicine. 2021; 9(1): e56 HCWs and the provision of PPE are of particular importance to maintaining ongoing care and the function of the health care system. On another hand, Liu et al. showed that the rate of RNA virus was reduced by performing a disinfection procedure in the PPE room (29). This emphasizes the effect of environmental disinfection in reduction of virus transmis- sion (29). Therefore, in addition to providing PPE for HCWs, health or- ganizations should emphasize continuous training on don- ning and doffing for effective protection (34, 35). Study re- sults showed that the infection control team of the hospital can significantly reduce the transmission of the disease be- tween HCWs through early diagnosis and identifying index cases among patients and explaining preventive actions to them, giving early leave to sick staff, or at least giving them some recommendations such as maintaining social distance with other staff, hand hygiene observation, and wearing face- mask during a disease outbreak, and monitoring the adher- ence to infection control methods (26). In addition to HCWs’ awareness, climate condition is another factor that obstructs the correct use of respiratory protection equipment between HCWs (36). Studies state that in a household setting, due to the in- creased cumulative exposure time of index patients with family members, the possibility of transmitting viral respi- ratory infections is higher (37, 38). In this regard, results of studies showed that if family members perform non-drug interventions (such as wearing facemask and maintaining hand hygiene for the prevention of home flu), during 36 hours after onset of symptoms in the index case, the inci- dence of influenza will be significantly lower in family mem- bers compared to control group. One of the possible rea- sons is that the virus shedding often occurs during the first 36 hours so if the preventive interventions start sooner, the probability of home transmission of disease will be lower. Moreover, this study showed that the permanent use of face- mask is tolerable and acceptable for both adults and chil- dren. In this regard, another study on the effect of non-drug interventions (wearing facemask and hand hygiene) in home environments in Bangkok, Thailand failed to see any effect. Of course, it should be mentioned that index patients who were infected with Influenza (children) slept with their par- ents without wearing facemask throughout the night, which may block any effect of interventional protection during the day (39). In a random retrospective cluster clinical trial study, Mac- Intyre et al. revealed that less than 50% of participants had the necessary compliance for wearing a facemask and in this group had a significantly lower risk of Influenza-like illness due to infection (25). Results of another study in a social set- ting such as a student dormitory showed that influenza-like illness was significantly less in the group that used a face- mask, and the group that both used a facemask and main- tained hand hygiene compared to the control group. They suggested that adding hand disinfectant does not increase the protective efficacy of wearing a facemask or at least does not increase it significantly (40). Results of these studies show that if index patients and people around them do non-drug interventions such as wearing a facemask and washing their hands in domestic or social settings during the first 36 hours, these can significantly reduce the incidence of respiratory in- fection in people around them. One of the important religious rituals is Hajj, in which large numbers of people from different countries congregate in a particular region. Thus, it naturally increases the risk of transmitting respiratory viral infections. Results of studies show that use of facemasks by people with the influenza-like illness and those around them (those who were in a tent to- gether) provided more protection against the Influenza-like illness compared to those in the control group, who did not wear protective equipment, and the percentage of infection in each group was 31% vs. 53%, respectively. A significant point in this report was the presence of a positive correlation between duration of facemask use and protection against influenza-like illness, so the incidence of disease in pilgrims who wore facemask more than eight hours a day compared to those who wore a mask for less than eight hours a day was 3% vs 43% (21). Currently, due to the intensity of the COVID-19 pandemic, wearing a facemask is common everywhere, including hospi- tals and communities (3). In this regard, the results of studies indicate that wearing a facemask is more effective in control- ling the spread of infection, especially from asymptomatic carriers. The inward efficacy surpasses outward efficacy and the public’s use of facemasks plays a greater role in control- ling the source of infection. Of course, wearing a facemask is recommended as a method of infection control and primary prevention for healthy persons (26, 41). Lai et al showed that the use of facemask by HCWs is logical and the use of face- masks, even low-quality cloth masks, by the public should be implemented in the community, immediately. If people can use medical masks, without medical staff running out of PPE reserves, it will be more effective in the prevention of disease transmission. The use of cloth masks by patients or infec- tious individuals without clinical symptoms prevents infec- tion transmission in the community. Of course, the filtration effects of cloth masks are generally lower than surgical masks. However, if they are well designed (multi-layered cloth masks made of water-resistant fibers with high yarn density and del- icate cloth) and used properly (so that the whole face fits in it) they may provide reasonable protection. It has also been shown that these masks can decrease virus exposure, al- though their ability is much less than medical masks. There- fore, HCWs should not use this type of mask, since the re- This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem N. Shaterian et al. 6 sults of studies show that the risk of infection among HCWs who use cloth masks is higher than those who use the medi- cal mask or control group (42). Thus, CDC expressed that at the time of COVID-19 pandemic and due to the limited re- sources of medical masks, the public could use hand-made cloth masks to optimize facemask stocks. Also, they should be advised to wash their hands daily with hot water and soap, and other appropriate methods. Besides, the public should be educated about their use (27). Therefore, PPE should be selected for special settings and they should be used logically (4). It was thought that N95 respirators have more efficacy in filtering very small particles than surgical masks. However, the results of studies show that in non-infectious health care settings, surgical masks do not have lower protective efficacy than N95 respirators in HCWs (43-46). However, results of one cluster clinical trial showed that the rate of respiratory infections in HCWs who always use medical mask was double compared to HCWs who always used N95 respirators, and the highest rate of in- fection was among HCWs who had close contact with pa- tients such as radiologists, followed by nurses. Nevertheless, that study did not have enough power for the results to be generalized, since the rate of observed infection was much lower than expected (24). 5. Limitations The limitations of this study included lack of access to full- text of some studies, lack of data on the effect of facemasks on prevention of each type of respiratory viruses in articles that had studied different viruses, the lack of data on the ef- fect of each type of facemask on reducing the transmission of respiratory viruses and count or percentage of participants who used a facemask. Moreover, some studies conducted on recent viruses (SARS-Cov-2) were not published in English, which is another limitation of the study. 6. Conclusion This systematic review showed that using facemasks or res- pirators aided in preventing the spread of respiratory viruses. The result of the present systematic review showed that us- ing facemasks could prevent the spread of virus. We recom- mend conducting more studies on the effect of each type of facemask and respirator, individually, and on the prevention of the spread of different viruses. 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Emerging infectious diseases. 2004;10(2):280. 35. Ippolito M, Vitale F, Accurso G, Iozzo P, Gregoretti C, Giarratano A, et al. Medical masks and Respirators for the Protection of Healthcare Workers from SARS-CoV-2 and other viruses. Pulmonology. 2020. 36. Kuklane K, Lundgren K, Gao C, Löndahl J, Hornyan- szky ED, Östergren P-O, et al. Ebola: improving the design of protective clothing for emergency workers allows them to better cope with heat stress and help to contain the epidemic. Annals of Occupational Hygiene. 2015;59(2):258-61. 37. Bastola A, Sah R, Rodriguez-Morales AJ, Lal BK, Jha R, Ojha HC, et al. The first 2019 novel coronavirus case in Nepal. The Lancet Infectious Diseases. 2020;20(3):279-80. 38. Suess T, Remschmidt C, Schink SB, Schweiger B, Nitsche A, Schroeder K, et al. The role of facemasks and hand hygiene in the prevention of influenza transmission in households: results from a cluster randomised trial; Berlin, Germany, 2009-2011. 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Wiboonchutikul S, Manosuthi W, Likanonsakul S, Sangsajja C, Kongsanan P, Nitiyanontakij R, et al. Lack of transmission among healthcare workers in contact with a case of Middle East respiratory syndrome coronavirus in- fection in Thailand. Antimicrobial Resistance & Infection Control. 2016;5(1):21. This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem 9 Archives of Academic Emergency Medicine. 2021; 9(1): e56 Figure 1: Flowchart of the review. This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem N. Shaterian et al. 10 Table 1: Overview of all the studies included in this systematic review Reference Study design Location Population Sample size (N, %) Age (year) Result Quality score Amy Heinz- erling (2020)(16) Cohort California Healthcare Personnel T:43 M: 16% F: 84% 27 – 60 Reducing the risk of SARS-CoV-2 trans- mission using Patient source control (e.g., a patient wearing a facemask or connected to a closed-system ventila- tor during HCP exposures) 7* Hyun Kyun Ki (2019)(32) Case–Cohort Korea Emergency department and general ward T: 446 M: 46.9% F: 53.1% 20 - 78 Great reduction in nosocomial trans- mission of MERS by routine infection- prevention policies such as wearing a surgical mask and hand hygiene 9* Boyeong Ryu (2018)(19) cross- sectional Korea Public health work- ers T: 34 M: 58.8% F: 41.1% 34 – 56.7 Properly use of PPE lead to a lack of evidence of MERS on Public Health Provider Basem M. Alraddadi 7* (2016)(20) Cohort Saudi Arabia Healthcare Personnel T: 250 M: 64.4% F: 35.6% 18 - 66 - more protective against MERS CoV infection while in close contact with an infected patient by N95 respirators - highlight the possible role of short- range aerosol transmission of MERS- CoV in healthcare settings 7* Surasak Wi- boonchutikul (2016)(47) Cross- sectional Thailand Healthcare workers T:38 M: 21.1% F: 78.9% 38.6 Healthcare workerscan be protected via strict infection control precaution 7* Osamah Barasheed (2014)(21) Controlled trial Saudi Arabia Australian Hajj Pilgrims T: 164 M: 43.3% F: 56.7% 19-80 The positive association between the duration of facemask use and protec- tion against ILI 20** Thorsten Suess (2012)(38) Controlled trial Germany Households T: 302 M: 51.6% F: 48.3% 4-43 Interruption of influenza transmission within households by using a facemask 22** Jenifer L. Jaeger (2011)(31) Cohort California Healthcare Personnel T: 63 M: 23.8% F: 76.2% 19–74 A significant association between us- ing facemask or N95 respirator and seronegative and asymptomatic respi- ratory disease 8* Chandini Raina MacIntyre (2011)(24) Controlled trial Australia Health care workers T: 1441 M: 9.9% F: 90.1% ≥ 18 - Approximately double rates of res- piratory tract infection in the medi- cal mask group compared to the N95 group among healthcare workers - Sig- nificant protection against CRI using N95 non-fit tested arm 21** Chandini Raina MacIntyre (2009)(25) Controlled trial Sydney, New South Wales, Australia Households T: 284 ≥ 0 The important role of using a facemask in preventing transmission 20** T: Total, M: Male, F: Female, PPE: Personal Protective Equipment, ILI: Influenza-like illness; HCP: Healthcare personnel ; CRI: clinical respiratory illness. *By Newcastle-Ottawa scale (NOS) **By Consolidated Standards of Reporting Trials (CONSORT) This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem 11 Archives of Academic Emergency Medicine. 2021; 9(1): e56 Table 2: Type of virus, contact, personal protective equipment (PPE), and facemask, and the number of people infected despite using a face- mask in studied articles Reference Type of virus Type of contact with an infected person PPE type (%) P_value Facemask type (%) Infected participants using a facemask and in contact with the patient (N) (%) Taking vital signs Gloves* (64.9%) Taking a medical history Performing a physical exam Providing medication Bathing or cleaning patient Lifting or positioning patient Amy SARS-CoV-2 Emptying bedpan Facemask (8.1%) NR** Yes:8.1% No:91.9% Heinzerling Changing linens (2020)(16) Cleaning patient room Peripheral line insertion Central line insertion Drawing arterial blood gas Drawing blood Manipulation of oxygen mask or tubing Manipulation of ventilator or tubing In-room while high-flow oxygen being delivered Collecting respiratory specimen Hyun Kyun Ki (2019)(32) MERS Touch of patient Mask or respirator (52.9%) P_value<0.05 Surgical mask(48.4%) P_value<0.001 Yes:0.8% No: 99.1% Touch of bed or equipment Gloves (0.8%) P_value=0.624 N95 respirator (4.4%) Patient transportation Patient counseling Boyeong Ryu (2018)(19) MERS-CoV Ambulance disinfection Facemask (100%) N95 respirator in participants (100%) Yes:2.9% No: 97.1% Specimen transportation Respiratory specimen collection Gloves Surgical mask in symptomatic pa- tients Taking vital signs Discarding exposed goods Other Basem M. Alraddadi (2016)(20) MERS-CoV Direct contact with patient Gloves (87.2%) Medical mask P_value>0.05 Yes:6.4% No: 93.6% Gown (87.2%) P_value=0.81 Aerosol-generating procedures Eye protection P_value>0.05 N95 respirator P_value>0.05 Facemask or respira- tor P_value>0.05 Touching the patient Gown (%100) Touching the patient’s equipment Gloves (%100) Surasak Wi- boonchutikul (2016)(47) MERS-CoV Examining clinical specimens Eye protection (%100) N95 respirator (100%) Yes:0% No:100% Obtaining clinical specimens Cap (%100) Cleaning the patient’s room Facemask (%100) Rhinovirus Influenza A (H1N1) Osamah Barasheed (2014)(21) Influenza B Dual infection (rhino & influenza A) Usual contact between people in Hajj Facemask (45.7%) P_value>0.05 Surgical mask (45.7%) P_value>0.05 Yes:11.1% No:88.8% This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem N. Shaterian et al. 12 Table 2: Type of virus, contact, personal protective equipment (PPE), and facemask, and the number of people infected despite using a face- mask in studied articles Reference Type of virus Type of contact with PPE type (%) P_value Facemask type (%) Infected participants an infected person using a facemask and in contact with the patient (N) (%) Parainfluenza 3 Enterovirus Thorsten Suess (2012)(38) Influenza A (H1N1) Household contacts Hygiene and facemask (31.4%) P_value=0.2 Surgical mask (62.9%) P_value<0.05 Yes:8.6% No:91.3% Influenza B Facemask (62.9%) 0.3 Encounters Gloves (71.4%) P_value>0.05 Mask P_value>0.05 Yes:14% No:86% Exposure to respira- tory secretions Gown P_value>0.05 Jenifer L. Jaeger (2011)(31) Influenza A (H1N1) Exposure before in- stitution of at least Droplet Precautions Facemask or N95 respira- tor (31.7%) P_value>0.05 N95 respirators P_value>0.05 Skin-to-skin contacts Total PPE use (73%) P_value>0.05 Adenoviruses N95 fit (32%) P_value=0.19 Chandini Raina MacIntyre (2011)(24) Human metapneu- movirus NR Facemask (100%) P_value=0.19 N95 non-fit (33.9%) P_value=0.03 Yes:1.8% No:98.2% Coronavirus 229E⁄NL63 Medical mask(34.1%) P_value=0.67 Parainfluenza viruses 1, 2 or 3 Influenza viruses A (H1N1) or B Respiratory syncytial virus A or B Rhinovirus A⁄B Coronavirus Influenza A (H1N1) Facemask (65.4%) Surgical mask (33%) Influenza B P_value=0.19 P_value=0.32 Adenoviruses Daily hand wash P_value=0.21 Respiratory syncytial virus Chandini Raina Mac- Intyre (2009) (25) Parainfluenza viruses 1,2 and 3 Household contacts P2 mask (32.4%) P_value=0.12 Yes:8% No:92% Human metapneu- movirus Coronavirus OC43 Using soap for washing hand P_value=0.87 Picornaviruses Rhinoviruses Enteroviruses Uncharacterized no Sequenced picor- naviruses *These percentages were reported from 37 health care workers who were tested for SARS-CoV-2 and participated in interviews in this study. ** NR: not reported This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem 13 Archives of Academic Emergency Medicine. 2021; 9(1): e56 Table 3: Quality assessments of controlled clinical trials ,based on CONSORT Item Osamah Barasheed (28) Thorsten Suess (45) Chandini Raina MacIntyre (31) Chandini Raina MacIntyre (32) 1.Identification as a randomized trial in the title structured summary of trial de- sign, methods, results, and conclusions (for specific guidance see CONSORT for abstracts) 1 1 1 1 2. Scientific background and explanation of rationale, specific objectives, or hy- potheses 1 1 1 1 3. Description of trial design (such as parallel, factorial) including allocation ratio Important changes to methods after trial commencement (such as eligibility cri- teria), with reasons 1 1 1 1 4. Eligibility criteria for participants Settings and locations where the data were collected 1 1 1 1 5. The interventions for each group with sufficient details to allow replication, in- cluding how and when they were actually administered 1 1 1 1 6. Completely defined pre-specified primary and secondary outcome measures, including how and when they were assessed Any changes to trial outcomes after the trial commenced, with reasons 1 1 1 1 7. How sample size was determined when applicable, explanation of any interim analyses and stopping guidelines 1 1 1 1 8. Method used to generate the random allocation sequence, type of randomisa- tion, details of any restriction (such as blocking and block size) 1 1 1 1 9. Mechanism used to implement the random allocation sequence (such as se- quentially numbered containers), describing any steps taken to conceal the se- quence until interventions were assigned 1 1 1 1 10. Who generated the random allocation sequence, who enrolled participants, and who assigned participants to interventions 1 1 1 1 11. If done, who was blinded after assignment to interventions (for example, par- ticipants, care providers, those assessing outcomes) and how If relevant, descrip- tion of the similarity of interventions 0 1 0 0 12. Statistical methods used to compare groups for primary and secondary out- comes Methods for additional analyses, such as subgroup analyses and adjusted analyses 1 1 1 1 13. For each group, the numbers of participants who were randomly assigned, re- ceived intended treatment, and were analysed for the primary outcome For each group, losses and exclusions after randomisation, together with reasons 1 1 1 1 14. Dates defining the periods of recruitment and follow-up Why the trial ended or was stopped 1 1 1 1 15. A table showing baseline demographic and clinical characteristics for each group 1 1 1 1 16. For each group, number of participants (denominator) included in each anal- ysis and whether the analysis was by original assigned groups 1 1 1 1 17. For each primary and secondary outcome, results for each group, and the es- timated effect size and its precision (such as 95% confidence interval) For binary outcomes, presentation of both absolute and relative effect sizes is recommended 0 0 0 0 18. Results of any other analyses performed, including subgroup analyses and ad- justed analyses, distinguishing pre-specified from exploratory 0 1 0 1 19. All-important harms or unintended effects in each group (for specific guidance see CONSORT for harms) 1 1 1 0 20. Trial limitations, addressing sources of potential bias, imprecision, and, if rele- vant, multiplicity of analyses 1 0 1 1 21. Generalisability (external validity, applicability) of the trial findings 1 1 1 1 22. Interpretation consistent with results, balancing benefits and harms, and con- sidering other relevant evidence 1 1 1 1 23. Registration number and name of trial registry 0 0 0 0 24. Where the full trial protocol can be accessed, if available 0 0 0 0 25. Sources of funding and other support (such as supply of drugs), role of funders 1 1 1 1 Total Score 20 22 21 20 This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem N. Shaterian et al. 14 Table 4: Quality assessments of studiesbased onNEWCASTLE - OTTAWA Study Year Study type Selection Comparability Outcome Amy Heinzerling (17) 2012 Cohort **** - *** Basem M. Alraddadi (21) 2020 Cohort *** * *** Jenifer L. Jaeger (32) 2012 Cohort *** * *** Hyun Kyun Ki (33) 2011 Cohort ***** * *** Boyeong Ryu (20) 2010 Cross-Sectional *** ** ** SurasakWiboonchutikul (48) 2016 Cross-Sectional *** ** ** This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem Introduction Methods Results Discussion Limitations Conclusion Declarations References