what are the best masks for preventing infection by Covid-19?

COVID-19 pandemic is now a global threat on human health reaching up to 2 million infected people all around the World. Since its first recognition in Wuhan, many topics were discussed intensively about COVID-19, both in the public and scientific community. Personal protective equipments and especially masks were among the hottest topics during this pandemic. Regardless of which mask is used, performing hand hygiene frequently with an alcohol-based hand rub or with soap and water if hands are dirty; is the most effective preventive measure for COVID-19. The type of mask used when caring for COVID-19 patients will vary according to the setting, type of personnel/person, and activity. Although the main transmission route for COVID-19 is droplets, during aerosol generating procedures airborne transmission may occur. Keeping the distancing and medical masks and eye protection during close contact efficiently protects against respiratory diseases transmitted via droplets. Airborne precautions include goggles and respiratory protection with the use of an N95 or an equivalent mask respirator to prevent airborne transmission.

Medical mask or N95 respirator: When and how to use?

COVID-19 pandemic is now a global threat to human health reaching up to 2 million infected people all around the world. Since its first recognition in Wuhan, many topics were discussed intensively about COVID-19, both in the public and scientific community. Personal protective equipment, especially masks, has been among the hottest topics during this pandemic. Regardless of which mask is used, performing hand hygiene frequently with an alcohol-based hand rub or with soap and water if hands are dirty is the most effective preventive measure for COVID-19. The type of mask used when caring for COVID-19 patients will vary according to the setting, type of personnel/person, and activity. Although the main transmission route for COVID-19 is droplets, during aerosol generating procedures airborne transmission may occur. Keeping the distancing and medical masks and eye protection during close contact efficiently protects against respiratory diseases transmitted via droplets. Airborne precautions include goggles and respiratory protection with the use of an N95 or an equivalent mask respirator to prevent airborne transmission.

The coronavirus disease 2019 (COVID-19) [2019-nCoV; severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)] was first detected in Wuhan, China at the end of 2019. In current status, spread of CO-VID-19 in person-to-person could be caused mainly by respiratory droplets, which leads to the spread of the influenza virus in both community and clinicians. Thus, in order to reduce the risk of that, the urgent management strategies against COVID-19 are to block transmission, isolation, protection, and using drug or vaccine updated on an ongoing basis. unfortunately, no drugs or vaccines still has yet been allowed to treat patients with COVID-19, so the rapid detection of effective intercessions against COVID-19 is seemed a major challenge on the all world. Herein, this article attempts summarizing to introduce the characterization of COVID-19, the influence of droplets travel in person-to-person transmission and the effect of wearing masks in the infection prevention of influenza virus, as well as understanding its advantage and role in the coronavirus infection prevention.

Coronavirus infection prevention by wearing masks

Controversy exists around the appropriate types of masks and the situations in which they should be used in community and health care settings for the prevention of SARS-CoV-2 infection. In this article, the American College of Physicians (ACP) provides recommendations based on the best available evidence through 14 April 2020 on the effectiveness of N95 respirators, surgical masks, and cloth masks in reducing transmission of infection. The ACP plans periodic updates of these recommendations on the basis of ongoing surveillance of the literature for 1 year from the initial search date.

Use of N95, Surgical, and Cloth Masks to Prevent COVID-19 in Health Care and Community Settings: Living Practice Points From the American College of Physicians (Version 1)

BACKGROUND: Respiratory protective devices are critical in protecting against infection in healthcare workers at high risk of novel 2019 coronavirus disease (COVID-19); however, recommendations are conflicting and epidemiological data on their relative effectiveness against COVID-19 are limited. PURPOSE: To compare medical masks to N95 respirators in preventing laboratory-confirmed viral infection and respiratory illness including coronavirus specifically in healthcare workers. DATA SOURCES: MEDLINE, Embase, and CENTRAL from January 1, 2014, to March 9, 2020. Update of published search conducted from January 1, 1990, to December 9, 2014. STUDY SELECTION: Randomized controlled trials (RCTs) comparing the protective effect of medical masks to N95 respirators in healthcare workers. DATA EXTRACTION: Reviewer pair independently screened, extracted data, and assessed risk of bias and the certainty of the evidence. DATA SYNTHESIS: Four RCTs were meta-analyzed adjusting for clustering. Compared with N95 respirators; the use of medical masks did not increase laboratory-confirmed viral (including coronaviruses) respiratory infection (OR 1.06; 95% CI 0.90-1.25; I2 = 0%; low certainty in the evidence) or clinical respiratory illness (OR 1.49; 95% CI: 0.98-2.28; I2 = 78%; very low certainty in the evidence). Only one trial evaluated coronaviruses separately and found no difference between the two groups (P = .49). LIMITATIONS: Indirectness and imprecision of available evidence. CONCLUSIONS: Low certainty evidence suggests that medical masks and N95 respirators offer similar protection against viral respiratory infection including coronavirus in healthcare workers during non-aerosol-generating care. Preservation of N95 respirators for high-risk, aerosol-generating procedures in this pandemic should be considered when in short supply.

Medical masks vs N95 respirators for preventing COVID-19 in healthcare workers: A systematic review and meta-analysis of randomized trials

Cloth masks have been used in healthcare and community settings to protect the wearer from respiratory infections. The use of cloth masks during the coronavirus disease (COVID-19) pandemic is under debate. The filtration effectiveness of cloth masks is generally lower than that of medical masks and respirators; however, cloth masks may provide some protection if well designed and used correctly. Multilayer cloth masks, designed to fit around the face and made of water-resistant fabric with a high number of threads and finer weave, may provide reasonable protection. Until a cloth mask design is proven to be equally effective as a medical or N95 mask, wearing cloth masks should not be mandated for healthcare workers. In community settings, however, cloth masks may be used to prevent community spread of infections by sick or asymptomatically infected persons, and the public should be educated about their correct use.

Effectiveness of Cloth Masks for Protection Against Severe Acute Respiratory Syndrome Coronavirus 2

Effectiveness of Cloth Masks for Protection Against Severe Acute Respiratory Syndrome Coronavirus 2.

The Coronavirus Disease 2019 (COVID-19) has swept the whole world with high mortality. Since droplet transmission is the main route of transmission, wearing a mask serves as a crucial preventive measure. However, the virus has spread quite quickly, causing severe mask shortage. Finding alternative materials for homemade masks while ensuring the significant performance indicators will help alleviate the shortage of masks. Referring to the national standard for the "Surgical Mask" of China, 17 materials to be selected for homemade masks were tested in four key indicators: pressure difference, particle filtration efficiency, bacterial filtration efficiency and resistance to surface wetting. Eleven single-layer materials met the standard of pressure difference ([≤]49 Pa), of which 3 met the standard of resistance to surface wetting ([≥]3), 1 met the standard of particle filtration efficiency ([≥]30%), but none met the standard of bacterial filtration efficiency ([≥]95%). Based on the testing results of single-layer materials, fifteen combinations of paired materials were tested. The results showed that three double-layer materials including double-layer medical non-woven fabric, medical non-woven fabric plus non-woven shopping bag, and medical non-woven fabric plus granular tea towel could meet all the standards of pressure difference, particle filtration efficiency, and resistance to surface wetting, and were close to the standard of the bacterial filtration efficiency. In conclusion, if resources are severely lacking and medical masks cannot be obtained, homemade masks using available materials, based on the results of this study, can minimize the chance of infection to the maximum extent.

Selection of homemade mask materials for preventing transmission of COVID-19: a laboratory study

Coronavirus disease 2019 is an infectious disease caused by severe acute respiratory syndrome coronavirus 2. It has taken a toll of lots of lives since its outbreak. Infection prevention at present is an appropriate control measure in addition to other measure like hand hygiene and personal protective equipment (PPE). In our country with a large population, supplying PPE to all the health care workers of all hospitals definitely is an economic burden. Hence we have come up with an economic and simple solution for face mask.

Simple Economical Solution for Personal Protection Equipment (Face Mask/Shield) for Health Care Staff During COVID 19

BACKGROUND: Respiratory protective devices are critical in protecting against infection in healthcare workers at high risk of novel 2019 coronavirus disease (COVID‐19); however, recommendations are conflicting and epidemiological data on their relative effectiveness against COVID‐19 are limited. PURPOSE: To compare medical masks to N95 respirators in preventing laboratory‐confirmed viral infection and respiratory illness including coronavirus specifically in healthcare workers. DATA SOURCES: MEDLINE, Embase, and CENTRAL from January 1, 2014, to March 9, 2020. Update of published search conducted from January 1, 1990, to December 9, 2014. STUDY SELECTION: Randomized controlled trials (RCTs) comparing the protective effect of medical masks to N95 respirators in healthcare workers. DATA EXTRACTION: Reviewer pair independently screened, extracted data, and assessed risk of bias and the certainty of the evidence. DATA SYNTHESIS: Four RCTs were meta‐analyzed adjusting for clustering. Compared with N95 respirators; the use of medical masks did not increase laboratory‐confirmed viral (including coronaviruses) respiratory infection (OR 1.06; 95% CI 0.90‐1.25; I (2) = 0%; low certainty in the evidence) or clinical respiratory illness (OR 1.49; 95% CI: 0.98‐2.28; I (2) = 78%; very low certainty in the evidence). Only one trial evaluated coronaviruses separately and found no difference between the two groups (P = .49). LIMITATIONS: Indirectness and imprecision of available evidence. CONCLUSIONS: Low certainty evidence suggests that medical masks and N95 respirators offer similar protection against viral respiratory infection including coronavirus in healthcare workers during non–aerosol‐generating care. Preservation of N95 respirators for high‐risk, aerosol‐generating procedures in this pandemic should be considered when in short supply.

Medical masks vs N95 respirators for preventing COVID‐19 in healthcare workers: A systematic review and meta‐analysis of randomized trials

Background: Conflicting recommendations exist related to whether masks have a protective effect on the spread of respiratory viruses. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement was consulted to report this systematic review. Relevant articles were retrieved from PubMed, Web of Science, ScienceDirect, Cochrane Library, and Chinese National Knowledge Infrastructure (CNKI), VIP (Chinese) database. Results: A total of 21 studies met our inclusion criteria. Meta-analyses suggest that mask use provided a significant protective effect (OR = 0.35 and 95% CI = 0.24-0.51). Use of masks by healthcare workers (HCWs) and non-healthcare workers (Non-HCWs) can reduce the risk of respiratory virus infection by 80% (OR = 0.20, 95% CI = 0.11-0.37) and 47% (OR = 0.53, 95% CI = 0.36-0.79). The protective effect of wearing masks in Asia (OR = 0.31) appeared to be higher than that of Western countries (OR = 0.45). Masks had a protective effect against influenza viruses (OR = 0.55), SARS (OR = 0.26), and SARS-CoV-2 (OR = 0.04). In the subgroups based on different study designs, protective effects of wearing mask were significant in cluster randomized trials, case-control studies and retrospective studies. Conclusions: This study adds additional evidence of the enhanced protective value of masks, we stress that the use masks serve as an adjunctive method regarding the COVID-19 outbreak.

Efficacy of face mask in preventing respiratory virus transmission: a systematic review and meta-analysis

Coronavirus disease 2019 is an infectious disease caused by severe acute respiratory syndrome coronavirus 2. It has taken a toll of lots of lives since its outbreak. Infection prevention at present is an appropriate control measure in addition to other measure like hand hygiene and personal protective equipment (PPE). In our country with a large population, supplying PPE to all the health care workers of all hospitals definitely is an economic burden. Hence we have come up with an economic and simple solution for face mask. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s12070-020-01863-4) contains supplementary material, which is available to authorized users.

BACKGROUND: Conflicting recommendations exist related to whether masks have a protective effect on the spread of respiratory viruses. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement was consulted to report this systematic review. Relevant articles were retrieved from PubMed, Web of Science, ScienceDirect, Cochrane Library, and Chinese National Knowledge Infrastructure (CNKI), VIP (Chinese) database. RESULTS: A total of 21 studies met our inclusion criteria. Meta-analyses suggest that mask use provided a significant protective effect (OR = 0.35 and 95% CI = 0.24–0.51). Use of masks by healthcare workers (HCWs) and non-healthcare workers (Non-HCWs) can reduce the risk of respiratory virus infection by 80% (OR = 0.20, 95% CI = 0.11–0.37) and 47% (OR = 0.53, 95% CI = 0.36–0.79). The protective effect of wearing masks in Asia (OR = 0.31) appeared to be higher than that of Western countries (OR = 0.45). Masks had a protective effect against influenza viruses (OR = 0.55), SARS (OR = 0.26), and SARS-CoV-2 (OR = 0.04). In the subgroups based on different study designs, protective effects of wearing mask were significant in cluster randomized trials and observational studies. CONCLUSIONS: This study adds additional evidence of the enhanced protective value of masks, we stress that the use masks serve as an adjunctive method regarding the COVID-19 outbreak.

Efficacy of face mask in preventing respiratory virus transmission: A systematic review and meta-analysis

BACKGROUND: Conflicting recommendations exist related to whether masks have a protective effect on the spread of respiratory viruses. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement was consulted to report this systematic review. Relevant articles were retrieved from PubMed, Web of Science, ScienceDirect, Cochrane Library, and Chinese National Knowledge Infrastructure (CNKI), VIP (Chinese) database. RESULTS: A total of 21 studies met our inclusion criteria. Meta-analyses suggest that mask use provided a significant protective effect (OR = 0.35 and 95% CI = 0.24-0.51). Use of masks by healthcare workers (HCWs) and non-healthcare workers (Non-HCWs) can reduce the risk of respiratory virus infection by 80% (OR = 0.20, 95% CI = 0.11-0.37) and 47% (OR = 0.53, 95% CI = 0.36-0.79). The protective effect of wearing masks in Asia (OR = 0.31) appeared to be higher than that of Western countries (OR = 0.45). Masks had a protective effect against influenza viruses (OR = 0.55), SARS (OR = 0.26), and SARS-CoV-2 (OR = 0.04). In the subgroups based on different study designs, protective effects of wearing mask were significant in cluster randomized trials and observational studies. CONCLUSIONS: This study adds additional evidence of the enhanced protective value of masks, we stress that the use masks serve as an adjunctive method regarding the COVID-19 outbreak.

Protecting Health Care Workers (HCWs) during routine care of suspected or confirmed COVID-19 patients is of paramount importance to halt the SARS-CoV-2 (Severe Acute Respiratory Syndrome-Coronavirus-2) pandemic. The WHO, ECDC and CDC have issued conflicting guidelines on the use of respiratory filters (N95) by HCWs. We searched PubMed, Embase and The Cochrane Library from the inception to March 21, 2020 to identify randomized controlled trials (RCTs) comparing N95 respirators versus surgical masks for prevention of COVID-19 or any other respiratory infection among HCWs. The grading of recommendations, assessment, development, and evaluation (GRADE) was used to evaluate the quality of evidence. Four RCTs involving 8736 HCWs were included. We did not find any trial specifically on prevention of COVID-19. However, wearing N95 respirators can prevent 73 more (95% CI 46–91) clinical respiratory infections per 1000 HCWs compared to surgical masks (2 RCTs; 2594 patients; low quality of evidence). A protective effect of N95 respirators in laboratory-confirmed bacterial colonization (RR = 0.41; 95%CI 0.28–0.61) was also found. A trend in favour of N95 respirators was observed in preventing laboratory-confirmed respiratory viral infections, laboratory-confirmed respiratory infection, and influenza like illness. We found no direct high quality evidence on whether N95 respirators are better than surgical masks for HCWs protection from SARS-CoV-2. However, low quality evidence suggests that N95 respirators protect HCWs from clinical respiratory infections. This finding should be contemplated to decide the best strategy to support the resilience of healthcare systems facing the potentially catastrophic SARS-CoV-2 pandemic.

The need of health policy perspective to protect Healthcare Workers during COVID-19 pandemic. A GRADE rapid review on the N95 respirators effectiveness

The scarcity of facemasks, particularly N95 respirators, combined with the lack of solid data to address the suitability of each mask type for adequate health care worker (HCW) protection have caused turmoil among HCWs. Current recommendations suggest mask usage solely during HCW contact with Covid-19 patients, namely plain medical mask for low-risk contacts and N95 for aerosol generating procedures. The distinction regarding the escalation of mask complexity depending on contact type is nevertheless based on plausible theoretical assumptions rather than hard evidence of a clear benefit. Conversely, we suggest that at least a plain mask should be used during all HCWs' contacts in healthcare facilities which constitute a highly probable but often overlooked means of SARS-CoV-2 transmission among HCWs.

Providing evidence on the ongoing health care workers' mask debate

Protecting Health Care Workers (HCWs) during routine care of suspected or confirmed COVID-19 patients is of paramount importance to halt the SARS-CoV-2 (Severe Acute Respiratory Syndrome-Coronavirus-2) pandemic. The WHO, ECDC and CDC have issued conflicting guidelines on the use of respiratory filters (N95) by HCWs. We searched PubMed, Embase and The Cochrane Library from the inception to March 21, 2020 to identify randomized controlled trials (RCTs) comparing N95 respirators versus surgical masks for prevention of COVID-19 or any other respiratory infection among HCWs. The grading of recommendations, assessment, development, and evaluation (GRADE) was used to evaluate the quality of evidence. Four RCTs involving 8736 HCWs were included. We did not find any trial specifically on prevention of COVID-19. However, wearing N95 respirators can prevent 73 more (95% CI 46-91) clinical respiratory infections per 1000 HCWs compared to surgical masks (2 RCTs; 2594 patients; low quality of evidence). A protective effect of N95 respirators in laboratory-confirmed bacterial colonization (RR = 0.41; 95%CI 0.28-0.61) was also found. A trend in favour of N95 respirators was observed in preventing laboratory-confirmed respiratory viral infections, laboratory-confirmed respiratory infection, and influenza like illness. We found no direct high quality evidence on whether N95 respirators are better than surgical masks for HCWs protection from SARS-CoV-2. However, low quality evidence suggests that N95 respirators protect HCWs from clinical respiratory infections. This finding should be contemplated to decide the best strategy to support the resilience of healthcare systems facing the potentially catastrophic SARS-CoV-2 pandemic.

The COVID-19 (Coronavirus disease 2019) spreads primarily through droplets of saliva or discharge from the nose. COVID-19 is predominantly considered as an unavoidable pandemic, and scientists are very curious about how to provide the best protection to the public before a vaccine can be made available. There is an urge to manufacture a greater number of masks to prevent any aerosol with microbes. Hence, we aim to develop an efficient viral inactivation system by exploiting active compounds from naturally occurring medicinal plants and infusing them into nanofiber-based respiratory masks. Our strategy is to develop fibrous filtration with three-layered masks using the compounds from medicinal plants for viral deactivation. These masks will be beneficial not just to healthcare workers but common citizens as well. In the absence of vaccination, productive masks can be worn to prevent transmission of airborne pathogenic aerosols and control diseases.

COVID-19: emerging protective measures

COVID-19: emerging protective measures.

Cloth Masks May Prevent Transmission of COVID-19: An Evidence-Based, Risk-Based Approach

Cloth masks versus medical masks for COVID-19 protection.

The use of face masks in public settings has been widely recommended by public health officials during the current COVID-19 pandemic. The masks help mitigate the risk of cross-infection via respiratory droplets; however, there are no specific guidelines on mask materials and designs that are most effective in minimizing droplet dispersal. While there have been prior studies on the performance of medical-grade masks, there are insufficient data on cloth-based coverings, which are being used by a vast majority of the general public. We use qualitative visualizations of emulated coughs and sneezes to examine how material- and design-choices impact the extent to which droplet-laden respiratory jets are blocked. Loosely folded face masks and bandana-style coverings provide minimal stopping-capability for the smallest aerosolized respiratory droplets. Well-fitted homemade masks with multiple layers of quilting fabric, and off-the-shelf cone style masks, proved to be the most effective in reducing droplet dispersal. These masks were able to curtail the speed and range of the respiratory jets significantly, albeit with some leakage through the mask material and from small gaps along the edges. Importantly, uncovered emulated coughs were able to travel notably farther than the currently recommended 6-ft distancing guideline. We outline the procedure for setting up simple visualization experiments using easily available materials, which may help healthcare professionals, medical researchers, and manufacturers in assessing the effectiveness of face masks and other personal protective equipment qualitatively.

Visualizing the effectiveness of face masks in obstructing respiratory jets

'The Mask' has become a byword and a precious possession universally. Except for its use by the medical fraternity, answers to the common questions-whether it provides enough protection, which type is optimal for the general public and who really needs to don it, remain poorly understood. For a frontline healthcare worker, wearing mask is a necessity as an important person protection equipment, it is perhaps the most-powerful psychological symbol for the general public. Surprisingly, it even undermines all other recommended practices of infection control and breaking the transmission chain of Covid-19, like hand washing, personal hygiene and social distancing. 'The mask' has evolved with time and yet there is a need to further improve the design for safety, tolerability and comfort. In this review we present the journey of face mask, originating from the first masks aimed at stopping the bad smell to its industrial use to its all-important place in the medical field. Various types of face masks, their filtration efficiency, reusability and current recommendations for their use are presented.

The Face Mask How a Real Protection becomes a Psychological Symbol during Covid-19?

Background Protecting Health Care Workers (HCWs) during routine care of suspected or confirmed COVID-19 patients is of paramount importance to halt the SARS-CoV-2 (Severe Acute Respiratory Syndrome-Coronavirus-2) pandemic. The WHO, ECDC and CDC have issued conflicting guidelines on the use of respiratory filters (N95) by HCWs. Methods We searched PubMed, Embase and The Cochrane Library from the inception to March 21, 2020 to identify randomized controlled trials (RCTs) comparing N95 respirators versus surgical masks for prevention of COVID-19 or any other respiratory infection among HCWs. The grading of recommendations, assessment, development, and evaluation (GRADE) was used to evaluate the quality of evidence. Findings Four RCTs involving 8736 HCWs were included. We did not find any trial specifically on prevention of COVID-19. However, wearing N95 respirators can prevent 73 more (95% CI 46-91) clinical respiratory infections per 1000 HCWs compared to surgical masks (2 RCTs; 2594 patients; low quality of evidence). A protective effect of N95 respirators in laboratory-confirmed bacterial colonization (RR= 0.41; 95%CI 0.28-0.61) was also found. A trend in favour of N95 respirators was observed in preventing laboratory-confirmed respiratory viral infections, laboratory-confirmed respiratory infection, and influenza like illness. Interpretation We found no direct high quality evidence on whether N95 respirators are better than surgical masks for HCWs protection from SARS-CoV-2. However, low quality evidence suggests that N95 respirators protect HCWs from clinical respiratory infections. This finding should be contemplated to decide the best strategy to support the resilience of healthcare systems facing the potentially catastrophic SARS-CoV-2 pandemic.

The need of health policy perspective to protect Healthcare Workers during COVID-19 pandemic. A GRADE rapid review on the N95 respirators effectiveness.

The outbreak of Novel Coronavirus is causing an intensely feared globally. World Health Organization has even declared that it is a global health emergency. The simplest method to limit the spread of this new virus and for people to protect themselves as well as the others is to wear a mask in crowded places. The sudden increase demand on face mask has caused manufacturers the inability to not provide enough products in a short time and the situation properly will stay the same for a period of time. In this article, we aim to give an idea on how to save the number of face masks used but still provides the same protective values using a Cardiopulmonary resuscitation (CPR) mask and a common surgical facemask.

A Reusable Mask for Coronavirus Disease 2019 (COVID-19)

The face mask: How a real protection becomes a psychological symbol during Covid-19?

In the context of Coronavirus Disease (2019) (COVID-19) cases globally, there is a lack of consensus across cultures on whether wearing face masks is an effective physical intervention against disease transmission. This study 1) illustrates transmission routes of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2); 2) addresses controversies surrounding the mask from perspectives of attitude, effectiveness, and necessity of wearing the mask with evidence that the use of mask would effectively interrupt the transmission of infectious diseases in both hospital settings and community settings; and 3) provides suggestion that the public should wear the mask during COVID-19 pandemic according to local context. To achieve this goal, government should establish a risk adjusted strategy of mask use to scientifically publicize the use of masks, guarantee sufficient supply of masks, and cooperate for reducing health resources inequities.

Mask use during COVID-19: A risk adjusted strategy

The scarcity of facemasks, particularly N95 respirators, combined with the lack of solid data to address the suitability of each mask type for adequate health care worker (HCW) protection have caused turmoil among HCWs. Current recommendations suggest mask usage solely during HCW contact with Covid-19 patients, namely plain medical mask for low-risk contacts and N95 for aerosol generating procedures. The distinction regarding the escalation of mask complexity depending on contact type is nevertheless based on plausible theoretical assumptions rather than hard evidence of a clear benefit. Conversely, we suggest that at least a plain mask should be used during all HCWs’ contacts in healthcare facilities which constitute a highly probable but often overlooked means of SARS-CoV-2 transmission among HCWs.

Providing evidence on the ongoing health care workers’ mask debate

The emergence of coronavirus disease 19 pandemic and novel research on the high transmissibility of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has raised controversies over the use of face masks to prevent community transmission. Specific regulations need to be fulfilled to use a face mask as part of the personal protective equipment and high quality of evidence supporting its use to prevent respiratory viral infections, including SARS-CoV-2, is lacking. However, its widespread use is becoming a standard practice in some countries and discrepancies between health authorities on their policy have led to controversy. The aim of this review is to provide an outlook on recent research in this matter and areas of opportunity.

UNIVERSAL MASKING DURING COVID-19 PANDEMIC - CURRENT EVIDENCE AND CONTROVERSIES.

OBJECTIVE: To determine if a repurposed silicone-based dressing used underneath a N95 mask is a safe and beneficial option for facial skin injury prevention without compromising the mask's seal. METHODS: Since February 21, 2020, staff in high risk areas such as the ED and ICU of King Hamad University Hospital have worn N95 masks when doing aerosol-generating procedures to protect against the novel coronavirus 2019. At that time, without education enablers or resources that could be directly translated into practice, the hospital's Pressure Injury Prevention Committee explored and created a stepwise process to protect the skin under these masks. This procedure was developed over time and tested to make sure that it did not interfere with the effectiveness of the N95 mask seal. RESULTS: Skin protection was achieved by repurposing a readily available silicone border dressing cut into strips. This was tested on 10 volunteer staff members of various skin types and both sexes who became part of this evidence generation project. Oxygen saturation values taken before and after the 4-hour wear test confirmed that well-fitted facial protection did not compromise the mask seal, but rather improved it. An added advantage was increased comfort with less friction as self-reported by the staff. An educational enabler to prevent MDRPI from N95 mask wear was an important additional resource for the staff. CONCLUSIONS: This creative and novel stepwise process of developing a safe skin protection method by which staff could apply a repurposed silicone border dressing beneath an N95 mask was largely effective and aided by the creation of the enabler.

Preventing Facial Pressure Injury for Health Care Providers Adhering to COVID-19 Personal Protective Equipment Requirements

OBJECTIVE: To determine if a repurposed silicone-based dressing used underneath a N95 mask is a safe and beneficial option for facial skin injury prevention without compromising the mask’s seal. METHODS: Since February 21, 2020, staff in high risk areas such as the ED and ICU of King Hamad University Hospital have worn N95 masks when doing aerosol-generating procedures to protect against the novel coronavirus 2019. At that time, without education enablers or resources that could be directly translated into practice, the hospital’s Pressure Injury Prevention Committee explored and created a stepwise process to protect the skin under these masks. This procedure was developed over time and tested to make sure that it did not interfere with the effectiveness of the N95 mask seal. RESULTS: Skin protection was achieved by repurposing a readily available silicone border dressing cut into strips. This was tested on 10 volunteer staff members of various skin types and both sexes who became part of this evidence generation project. Oxygen saturation values taken before and after the 4-hour wear test confirmed that well-fitted facial protection did not compromise the mask seal, but rather improved it. An added advantage was increased comfort with less friction as self-reported by the staff. An educational enabler to prevent MDRPI from N95 mask wear was an important additional resource for the staff. CONCLUSIONS: This creative and novel stepwise process of developing a safe skin protection method by which staff could apply a repurposed silicone border dressing beneath an N95 mask was largely effective and aided by the creation of the enabler.

OBJECTIVE The successful management of an influenza pandemic will be reliant on the expertise of healthcare workers at high risk for occupationally acquired influenza. Recommended infection control measures for healthcare workers include surgical masks to protect against droplet-spread respiratory transmissible infections and N95 masks to protect against aerosol-spread infections. A literature review was undertaken for evidence of superior protective value of N95 masks or surgical masks for healthcare workers against influenza and extraneous factors influencing conferred protection. METHODS Four scientific search engines using 12 search sequences identified 21 mask studies in healthcare settings for the prevention of transmission of respiratory syncytial virus, Bordetella pertussis, and severe acute respiratory syndrome. Each was critically assessed in accordance with Australian National Health Medical Research Council guidelines. An additional 25 laboratory-based publications were also reviewed. RESULTS All studies reviewed used medium or lower level evidence study design. In the majority of studies, important confounders included the unrecognized impact of concurrent bundling of other infection control measures, mask compliance, contamination from improper doffing of masks, and ocular inoculation. Only three studies directly compared the protective value of surgical masks with N95 masks. The majority of laboratory studies identified both mask types as having a range of filtration efficiency, yet N95 masks afford superior protection against particles of a similar size to influenza. CONCLUSIONS World Health Organization guidelines recommend surgical masks for all patient care with the exception of N95 masks for aerosol generating procedures. Because of the paucity of high-quality studies in the healthcare setting, the advocacy of mask types is not entirely evidence-based. Evidence from laboratory studies of potential airborne spread of influenza from shedding patients indicate that guidelines related to the current 1-meter respiratory zone may need to be extended to a larger respiratory zone and include protection from ocular inoculation.

Protecting healthcare workers from pandemic influenza: N95 or surgical masks?

Ma's research shows N95 masks, medical masks, even homemade masks could block at least 90% of the virus in aerosols(1). This study puts the debate on whether the public wear masks back on the table. Recently Science interviewed Dr. Gao, director‐general of Chinese Center for Disease Control and Prevention (CDC). This article is protected by copyright. All rights reserved.

Mask is the possible key for self‐isolation in COVID‐19 pandemic

The present COVID-19 pandemic, caused by the airborne SARS-CoV-2 virus, has highlighted the vital importance of appropriate personal protective equipment for all exposed health care workers The single most important part of this armor is the N-95 mask With the awareness that the virus is spread by both droplets and through the aerosolized route, the N-95 provides protection that a surgical mask cannot match This timely review looks at the special advantages that an N-95 offers over a surgical mask with specific reference to the COVID-19 epidemic It also emphasizes the crucial importance of ensuring quality masks with a proper fit Finally, with acute scarcities of N-95 masks being reported from hospitals globally, it reviews recent literature which attempts to prolong the life of these masks with extended use, reuse and decontamination of used masks

The N-95 mask: invaluable ally in the battle against the COVID-19 pandemic

Masks for Prevention of Respiratory Virus Infections, Including SARS-CoV-2, in Health Care and Community Settings: A Living Rapid Review

BACKGROUND: Recommendations on masks for preventing coronavirus disease 2019 (COVID-19) vary. PURPOSE: To examine the effectiveness of N95, surgical, and cloth masks in community and health care settings for preventing respiratory virus infections, and effects of reuse or extended use of N95 masks. DATA SOURCES: Multiple electronic databases, including the World Health Organization COVID-19 database and medRxiv preprint server (2003 through 14 April 2020; surveillance through 2 June 2020), and reference lists. STUDY SELECTION: Randomized trials of masks and risk for respiratory virus infection, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and observational studies of mask use and coronavirus infection risk were included. New evidence will be incorporated by using living review methods. DATA EXTRACTION: One reviewer abstracted data and assessed methodological limitations; a second reviewer provided verification. DATA SYNTHESIS: 39 studies (18 randomized controlled trials and 21 observational studies; 33 867 participants) were included. No study evaluated reuse or extended use of N95 masks. Evidence on SARS-CoV-2 was limited to 2 observational studies with serious limitations. Community mask use was possibly associated with decreased risk for SARS-CoV-1 infection in observational studies. In high- or moderate-risk health care settings, observational studies found that risk for infection with SARS-CoV-1 and Middle East respiratory syndrome coronavirus probably decreased with mask use versus nonuse and possibly decreased with N95 versus surgical mask use. Randomized trials in community settings found possibly no difference between N95 versus surgical masks and probably no difference between surgical versus no mask in risk for influenza or influenza-like illness, but compliance was low. In health care settings, N95 and surgical masks were probably associated with similar risks for influenza-like illness and laboratory-confirmed viral infection; clinical respiratory illness had inconsistency. Bothersome symptoms were common. LIMITATIONS: There were few SARS-CoV-2 studies, observational studies have methodological limitations, and the review was done by using streamlined methods. CONCLUSION: Evidence on mask effectiveness for respiratory infection prevention is stronger in health care than community settings. N95 respirators might reduce SARS-CoV-1 risk versus surgical masks in health care settings, but applicability to SARS-CoV-2 is uncertain. PRIMARY FUNDING SOURCE: Agency for Healthcare Research and Quality. Update Alerts: The authors have specified in the Methods section the interval and stop date for updates to this Living Review. As Annals receives updates, they will appear in the Comments section of the article on Annals.org. Reader inquiries about updates that are not available at approximately the specified intervals should be submitted as Comments to the article.

Are face masks useful for limiting the spread of COVID-19?

Cloth masks are a simple, economic and sustainable alternative to surgical mask as a means of source control of SARS-CoV-2 for general community.

Universal use of face masks for success against COVID-19: evidence and implications for prevention policies

The use of face masks for the general public has been suggested in literature as a means to decrease virus transmission during the global COVID-19 pandemic. However, literature findings indicate that most mask designs do not provide reliable protection. This paper investigates the hypothesis that the impaired protection is mainly due to imperfect fitting of the masks, so that airflow, which contains virus-transporting droplets, can leak through gaps into or out of the mask. The fluid dynamics of face masks are investigated via analytical and numerical computations. The results demonstrate that the flow can be satisfactorily predicted by simplified analytical 1D-flow models, by efficient 2D-flow simulations and by 3D-flow simulations. The present results show that already gap heights larger than 0.1mm can result in the mask not fulfilling FFP2 or FFP3 standards, and for gap heights of ca. 1mm most of the airflow and droplets may pass through the gap. The implications of these findings are discussed and improvements to existing mask designs are suggested.

Analytical and numerical investigation of the airflow in face masks used for protection against COVID-19 virus -- implications for mask design and usage

Mask use during COVID-19: A risk adjusted strategy()

Cloth masks versus medical masks for COVID-19 protection

Universal Masking during Covid-19 Pandemic - Current Evidence and Controversies

Abstract The outbreak of Novel Coronavirus is causing an intensely feared globally. World Health Organization has even declared that it is a global health emergency. The simplest method to limit the spread of this new virus and for people to protect themselves as well as the others is to wear a mask in crowded places. The sudden increase demand on face mask has caused manufacturers the inability to not provide enough products in a short time and the situation properly will stay the same for a period of time. In this article, we aim to give an idea on how to save the number of face masks used but still provides the same protective values using a Cardiopulmonary resuscitation (CPR) mask and a common surgical facemask.

Doctors need to wear complete protective equipment when large numbers of patients flood into the emergency room. Taiwan has so far managed to prevent a large scale community outbreak, city forces wearing face masks on public transportation, and keep social distancing to stem the virus from spreading. The protective device may be contaminated and must be replaced. In the situation of limited resources, how to take care of the physiological needs of the doctor without increasing the chance of contamination during replacement is a consideration. By reducing the chance of contamination during removal and storage, the previous designs were analyzed and improved. We proposed three improved designs to reduce the contact. Design-A features a mask with a water channel that allows the user to remain hydrated without removing the cover. Design-B has a folding pattern that hides the outer surface. Design-C combines the mask with the brim of a cap which form an extended air-intake area. Through understanding the problem, related product began distribute on the market, Design-D extend the mask usages period with less contact.

Face mask designs following novel Coronavirus

Do facemasks protect against COVID-19?

ABSTRACT Background The pandemic of COVID-19 is growing, and a shortage of masks and respirators has been reported globally. Policies of health organizations for healthcare workers are inconsistent, with a change in policy in the US for universal face mask use. The aim of this study was to review the evidence around the efficacy of masks and respirators for healthcare workers, sick patients and the general public. Methods A systematic review of randomized controlled clinical trials on use of respiratory protection by healthcare workers, sick patients and community members was conducted. Articles were searched on Medline and Embase using key search terms. Results A total of 19 randomised controlled trials were included in this study – 8 in community settings, 6 in healthcare settings and 5 as source control. Most of these randomised controlled trials used different interventions and outcome measures. In the community, masks appeared to be more effective than hand hygiene alone, and both together are more protective. Randomised controlled trials in health care workers showed that respirators, if worn continually during a shift, were effective but not if worn intermittently. Medical masks were not effective, and cloth masks even less effective. When used by sick patients randomised controlled trials suggested protection of well contacts. Conclusion The study suggests that community mask use by well people could be beneficial, particularly for COVID-19, where transmission may be pre-symptomatic. The studies of masks as source control also suggest a benefit, and may be important during the COVID-19 pandemic in universal community face mask use as well as in health care settings. Trials in healthcare workers support the use of respirators continuously during a shift. This may prevent health worker infections and deaths from COVID-19, as aerosolisation in the hospital setting has been documented.

A RAPID SYSTEMATIC REVIEW OF THE EFFICACY OF FACE MASKS AND RESPIRATORS AGAINST CORONAVIRUSES AND OTHER RESPIRATORY TRANSMISSIBLE VIRUSES FOR THE COMMUNITY, HEALTHCARE WORKERS AND SICK PATIENTS

Medical masks and Respirators for the Protection of Healthcare Workers from SARS-CoV-2 and other viruses

BACKGROUND: The pandemic of COVID-19 is growing, and a shortage of masks and respirators has been reported globally. Policies of health organizations for healthcare workers are inconsistent, with a change in policy in the US for universal face mask use. The aim of this study was to review the evidence around the efficacy of masks and respirators for healthcare workers, sick patients and the general public. METHODS: A systematic review of randomized controlled clinical trials on use of respiratory protection by healthcare workers, sick patients and community members was conducted. Articles were searched on Medline and Embase using key search terms. RESULTS: A total of 19 randomised controlled trials were included in this study - 8 in community settings, 6 in healthcare settings and 5 as source control. Most of these randomised controlled trials used different interventions and outcome measures. In the community, masks appeared to be effective with and without hand hygiene, and both together are more protective. Randomised controlled trials in health care workers showed that respirators, if worn continually during a shift, were effective but not if worn intermittently. Medical masks were not effective, and cloth masks even less effective. When used by sick patients randomised controlled trials suggested protection of well contacts. CONCLUSION: The study suggests that community mask use by well people could be beneficial, particularly for COVID-19, where transmission may be pre-symptomatic. The studies of masks as source control also suggest a benefit, and may be important during the COVID-19 pandemic in universal community face mask use as well as in health care settings. Trials in healthcare workers support the use of respirators continuously during a shift. This may prevent health worker infections and deaths from COVID-19, as aerosolisation in the hospital setting has been documented.

A rapid systematic review of the efficacy of face masks and respirators against coronaviruses and other respiratory transmissible viruses for the community, healthcare workers and sick patients

Abstract The use of medical masks and respirators as personal protective equipment is pivotal to reducing the level of biological hazard to which healthcare workers are exposed during the outbreak of highly diffusible pathogens, such as the recent novel coronavirus SARS-CoV-2. Unfortunately, during this pandemic, supplies are rapidly running out worldwide, with potential consequences for the rate of occupational infections. Also, knowledge about specific characteristics of respirators is of utmost importance to select the proper type according to the clinical setting. A wide variety of literature is available on the topic, but mostly based on Influenza viruses infection models. Clinical evidence on the use of respirators is poor and interest in the topic has not been constant over time. A better understanding of SARS-CoV-2 transmission is needed, together with high-quality clinical data on the use of respirators or alternative devices. Moreover, healthcare workers, regardless of their level of experience, should receive specific training. This review aims to summarize the available evidence on the use of medical masks and respirators in the context of viral infections, especially the current coronavirus disease 2019 (COVID-19).

Mask is the possible key for self-isolation in COVID-19 pandemic

Many governments have instructed the population to wear simple mouth-and-nose covers or surgical face masks to protect themselves from droplet infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in public. However, the basic protection mechanisms and benefits of these masks remain controversial. Therefore, the aim of this work is to show from a fluid physics point of view under which circumstances these masks can protect against droplet infection. First of all, we show that the masks protect people in the surrounding area quite well, since the flow resistance of the face masks effectively prevents the spread of exhaled air, e.g. when breathing, speaking, singing, coughing and sneezing. Secondly, we provide visual evidence that typical household materials used by the population to make masks do not provide highly efficient protection against respirable particles and droplets with a diameter of 0.3–2 μm as they pass through the materials largely unfiltered. According to our tests, only vacuum cleaner bags with fine dust filters show a comparable or even better filtering effect than commercial particle filtering FFP2/N95/KN95 half masks. Thirdly, we show that even simple mouth-and-nose covers made of good filter material cannot reliably protect against droplet infection in contaminated ambient air, since most of the air flows through gaps at the edge of the masks. Only a close-fitting, particle-filtering respirator without an outlet valve offers good self-protection and protection against droplet infection. Nevertheless, wearing simple homemade or surgical face masks in public is highly recommended if no particle filtrating respiratory mask is available. Firstly, because they protect against habitual contact of the face with the hands and thus serve as self-protection against contact infection. Secondly, because the flow resistance of the masks ensures that the air stays close to the head when breathing, speaking, singing, coughing and sneezing, thus protecting other people if they have sufficient distance from each other. However, if the distance rules cannot be observed and the risk of inhalation-based infection becomes high because many people in the vicinity are infectious and the air exchange rate is small, improved filtration efficiency masks are needed, to take full advantage of the three fundamental protective mechanisms these masks provide.

Fundamental protective mechanisms of face masks against droplet infections

The objective of this study was to investigate whether cotton mask worn by respiratory infection person could suppress respiratory droplet levels compared to medical mask. We recruited adult volunteers with confirmed influenza and suspected cases of coronavirus disease 2019 (COVID-19) to wear medical masks and self-designed triple-layer cotton masks in a regular bedroom and a car with air conditioning. Four 1-hour repeated measurements (two measurements for bedroom the others for car) of particles with a size range of 20-1000 nm measured by number concentrations (NC0.02-1), temperature and relatively humidity, and cough/sneeze counts per hour were conducted for each volunteer. The paired t-tests were used for within-group comparisons in a bedroom and in a car. The results showed that there was no significant difference in NC0.02-1 or cough/sneeze counts between volunteers with medical masks and cotton masks in a bedroom or a car. We concluded that the cotton mask could be a potential substitute for medical mask for respiratory infection person in microenvironment with air conditioning. Healthy people may daily use cotton mask in the community since cotton mask is washable and reusable.

Medical mask versus cotton mask for preventing respiratory droplet transmission in micro environments

Background The pandemic of COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS- CoV-2), has become a serious worldwide public health emergency. This systematic review aims to summarize the available evidence regarding the role of face mask in community settings in slowing the spread of respiratory viruses such as SARS- CoV-2. Methods The preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were used for this review. A literature search using PUBMED, Google Scholar, and Cochrane database were performed using Medical subject heading (MeSH) words from the year 2000-2020. The articles focused on the use of masks and N95 respirators in healthcare workers were excluded. Results A total of 305 records were identified, out of which 14 articles were included in the review based upon quality and eligibility criteria. All the articles mentioned about the role of face masks in preventing the spread of respiratory viruses like influenza, SARS, and SARS-CoV-2, in the community or experimental setting. Studies also suggested that early initiation of face mask usage was more effective. Masks were also reported to be more effective in viruses that transmit easily from asymptomatic individuals, as is now known in SARS-CoV-2. Conclusion Theoretical, experimental, and clinical evidence suggested that usage of face masks in a general population offered significant benefit in preventing the spread of respiratory viruses especially in the pandemic situation, but its utility is limited by inconsistent adherence to mask usage.

The use of facemasks by the general population to prevent transmission of Covid 19 infection: A systematic review.

As the COVID-19 pandemic progressed across the world, governments, international agencies, policymakers, and public health officials began recommending widespread use of nonmedical cloth masks to reduce the transmission of SARS-CoV-2. The authors of this article suggest that there is convincing evidence to support this recommendation.

Cloth Masks May Prevent Transmission of COVID-19: An Evidence-Based, Risk-Based Approach

Abstract The objective of this study was to investigate whether cotton mask worn by respiratory infection person could suppress respiratory droplet levels compared to medical mask. We recruited adult volunteers with confirmed influenza and suspected cases of coronavirus disease 2019 (COVID-19) to wear medical masks and self-designed triple-layer cotton masks in a regular bedroom and a car with air conditioning. Four 1-hour repeated measurements (two measurements for bedroom the others for car) of particles with a size range of 20–1000 nm measured by number concentrations (NC0.02–1), temperature and relatively humidity, and cough/sneeze counts per hour were conducted for each volunteer. The paired t-tests were used for within-group comparisons in a bedroom and in a car. The results showed that there was no significant difference in NC0.02–1 or cough/sneeze counts between volunteers with medical masks and cotton masks in a bedroom or a car. We concluded that the cotton mask could be a potential substitute for medical mask for respiratory infection person in microenvironment with air conditioning. Healthy people may daily use cotton mask in the community since cotton mask is washable and reusable.

COVID-19 and non-traditional mask use: How do various materials compare in reducing the infection risk for mask wearers?

Pandemics such as influenza, smallpox, and plague have caused the loss of hundreds of millions of lives and have occurred for many centuries. Fortunately, they have been largely eliminated by the use of vaccinations and drugs. More recently, Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome (MERS), and now Coronavirus Disease 2019 (COVID-19) have arisen, and given the current absence of highly effective approved vaccines or drugs, brute-force approaches involving physical barriers are being used to counter virus spread. A major basis for physical protection from respiratory infections is eye, nose, and mouth protection. However, eye protection with goggles is problematic due to "fogging", while nose/mouth protection is complicated by the breathing difficulties associated with non-valved respirators. Here, we give a brief review of the origins and development of face masks and eye protection to counter respiratory infections on the basis of experiments conducted 100 years ago, work that was presaged by the first use of personal protective equipment, "PPE", by the plague doctors of the 17th Century. The results of the review lead to two conclusions: first, that eye protection using filtered eye masks be used to prevent ocular transmission; second, that new, pre-filtered, valved respirators be used to even more effectively block viral transmission.

COVID-19 and Other Pandemics: How Might They Be Prevented?

On January 8, 2020, a novel coronavirus was officially announced as the causative pathogen of coronavirus disease (COVID-19) by the Chinese Center for Disease Control and Prevention.On February 26, COVID-19 has been recognized in 34 countries, with a total of 80,239 laboratory-confirmed patients and 2700 deaths.Protecting healthcare workers from infectious hazards is paramount to ensuring their safety in delivering health care.In addition, being able to protect healthcare workers, constituting the front-line response against high-threat respiratory pathogens, such as severe acute respiratory syndrome coronavirus 2, is important for reducing secondary transmission in healthcare-associated outbreaks.Authors present a simple, reliable, and cheap protocol to produce a custom-made sterilizable filtering facepiece 2/3 masks for healthcare providers during pandemic COVID-19 emergency.

How to Produce Cheap and Easy Custom-Made Sterilizable Filtering Facepiece 2/3 Masks for Healthcare Providers During Pandemic COVID-19 Emergency

Masks play a role in the protection of health-care workers (HCWs) from acquiring respiratory infections, including coronavirus disease 2019 (COVID-19) in health-care settings. This observational study was conducted among 382 HCWs in a tertiary care setting over a period of 1 month. Descriptive analysis was done to assess the rational and recommended use of masks/respirators during COVID-19 pandemic using a structured observation checklist as a survey tool. A total of 374 HCWs were included, 64.9% of whom were using face masks rationally as mentioned per risk area categorization with a predominance of triple-layered mask during all 4 weeks. Overall, 64.1% used masks correctly. Clear guidelines and strategies can help to increase the compliance of HCWs with rational use of face masks.

Rational use of face mask in a tertiary care hospital setting during COVID-19 pandemic: An observational study.

OBJECTIVES: To determine the risk of SARS-CoV-2 transmission by aerosols, to provide evidence on the rational use of masks, and to discuss additional measures important for the protection of healthcare workers from COVID-19. METHODS: Literature review and expert opinion. SHORT CONCLUSION: SARS-CoV-2, the pathogen causing COVID-19, is considered to be transmitted via droplets rather than aerosols, but droplets with strong directional airflow support may spread further than 2 m. High rates of COVID-19 infections in healthcare-workers (HCWs) have been reported from several countries. Respirators such as filtering face piece (FFP) 2 masks were designed to protect HCWs, while surgical masks were originally intended to protect patients (e.g., during surgery). Nevertheless, high quality standard surgical masks (type II/IIR according to European Norm EN 14683) appear to be as effective as FFP2 masks in preventing droplet-associated viral infections of HCWs as reported from influenza or SARS. So far, no head-to-head trials with these masks have been published for COVID-19. Neither mask type completely prevents transmission, which may be due to inappropriate handling and alternative transmission pathways. Therefore, compliance with a bundle of infection control measures including thorough hand hygiene is key. During high-risk procedures, both droplets and aerosols may be produced, reason why respirators are indicated for these interventions.

Risk of SARS-CoV-2 transmission by aerosols, the rational use of masks, and protection of healthcare workers from COVID-19

Masks and Coronavirus Disease 2019 (COVID-19)

Public health events caused by viruses pose a significant risk to humans worldwide. From December 2019 till now, the rampant novel 2019 coronavirus (SAR-CoV-2) has hugely impacted China and over world. Regarding a commendable means of protection, mask technology is relatively mature, though most of the masks cannot effectively resist the viral infections. The key material of the mask is a non-woven material, which makes the barrier of virus through filtration. Due to the lack of the ability to kill the viruses, masks are prone to cross-infection and become an additional source of infection after being discarded. If the filteration and antiviral effects can be simultaneously integrated into the mask, it will be more effcient, work for a longer time and create less difficulty in post-treatment. This mini-review presents the advances in antiviral materials, different mechanisms of their activity, and their potential applications in personal protective fabrics. Furthermore, the article addresses the future challenges and directions of mask technology.

Progress and Perspective of Antiviral Protective Material

Rational use of face mask in a tertiary care hospital setting during COVID-19 pandemic: An observational study

Wearing face masks regardless of symptoms is crucial for preventing the spread of COVID-19 in hospitals

Physical distancing, face masks, and eye protection for prevention of COVID-19

Background . Widespread use of masks in the general population is being used in many countries for Covid-19 . There has been reluctance on the part of the WHO and some governments to recommend this . Methodology . A basic model has been constructed to show the relative risk of aerosol from normal breathing in various situations together with the benefit from use of masks which is multiplicative . Results . Social distancing at 2 metres is validated but in confined areas is time limited and the use of masks in the absence of extremely good ventilation is important. Where social distancing is not possible at all times or an infectious person is in a confined area for a prolonged period there is a higher risk of infection requiring protection . Conclusions . The use of masks should be factored into models and used at an early stage as widespread use of more efficient masks could have a large impact on control and spread of infection . Public health planning requires stockpiling masks and encouraging everyone to have suitable masks in their household when supplies are normalised . The use of a cloth mask will be better than no protection at all .

A simple model to show the relative risk of viral aerosol infection and the benefit of wearing masks in different settings with implications for Covid-19 .

Role of Mask/Respirator Protection Against SARS-CoV-2

Role of mask/respirator protection against SARS-CoV-2

Respiratory infections may spread through droplets, airborne particles, and aerosols from infected individuals through coughing, sneezing, and speaking. In the case of Coronavirus Disease 2019 (COVID-19), droplet spread can occur from symptomatic as well as pre-symptomatic and asymptomatic persons. The U.S. Centers for Disease Control and Prevention (CDC) has therefore recently recommended home-made cloth face coverings for use by the general public in areas of significant community-based transmission. Because medical masks and N95 respirators are in short supply, these are to be reserved for healthcare workers. There is, however, little information on the effectiveness of home-made face coverings in reducing droplet dissemination. Here, we ascertained the performance of ten different fabrics, ranging from cotton to silk, in blocking high velocity droplets, using a 3-layered commercial medical mask as a benchmark material. We also assessed their breathability and ability to soak water. We reason that the materials should be as breathable as possible, without compromising blocking efficiency, to reduce air flow through the sides of the mask since such flow would defeat the purpose of the mask. We found that most home fabrics substantially block droplets, even as a single layer. With two layers, blocking performance can reach that of surgical mask without significantly compromising breathability. Furthermore, we observed that home fabrics are hydrophilic to varying degrees, and hence soak water. In contrast, medical masks are hydrophobic, and tend to repel water. Incoming droplets are thus soaked and 'held back' by home fabrics, which might offer an as of yet untapped and understudied advantage of home-made cloth masks. Overall, our study suggests that most double-layered cloth face coverings may help reduce droplet transmission of respiratory infections.

Performance of fabrics for home-made masks against spread of respiratory infection through droplets: a quantitative mechanistic study

Wearing masks and the fight against the novel coronavirus (COVID-19)

Masks and Coronavirus Disease 2019 (COVID-19).

During the COVID-19 pandemic, there is no agreement, until the current date, about the recommendations of homemade face mask use for the general population, and one of the reasons is a lack of information about their real protective rule on spreading aerosols and viruses. This is a comparative study regarding the relative efficiencies of commercial respiratory masks (medical masks) and homemade fabric masks, which may guide authorities across the globe, following the 'Advice on the use of masks in the context of COVID-19', by the World Health Organization. We described two optical methodologies for charactering respiratory masks. It happens that the aerosol scattering coefficient is linear as a function of its concentration inside the mask chamber. Quantitative optical properties of scattering for a large batch fabrication of masks were demonstrated, making the mask N95 suitable for use as a reference standard.

Aerosol blocking assessment by different types of fabrics for homemade respiratory masks: spectroscopy and imaging study

BACKGROUND Conflicting recommendations exist related to which facial protection should be used by health care workers to prevent transmission of acute respiratory infections, including pandemic influenza. We performed a systematic review of both clinical and surrogate exposure data comparing N95 respirators and surgical masks for the prevention of transmissible acute respiratory infections. METHODS We searched various electronic databases and the grey literature for relevant studies published from January 1990 to December 2014. Randomized controlled trials (RCTs), cohort studies and case-control studies that included data on health care workers wearing N95 respirators and surgical masks to prevent acute respiratory infections were included in the meta-analysis. Surrogate exposure studies comparing N95 respirators and surgical masks using manikins or adult volunteers under simulated conditions were summarized separately. Outcomes from clinical studies were laboratory-confirmed respiratory infection, influenza-like illness and workplace absenteeism. Outcomes from surrogate exposure studies were filter penetration, face-seal leakage and total inward leakage. RESULTS We identified 6 clinical studies (3 RCTs, 1 cohort study and 2 case-control studies) and 23 surrogate exposure studies. In the meta-analysis of the clinical studies, we found no significant difference between N95 respirators and surgical masks in associated risk of (a) laboratory-confirmed respiratory infection (RCTs: odds ratio [OR] 0.89, 95% confidence interval [CI] 0.64-1.24; cohort study: OR 0.43, 95% CI 0.03-6.41; case-control studies: OR 0.91, 95% CI 0.25-3.36); (b) influenza-like illness (RCTs: OR 0.51, 95% CI 0.19-1.41); or (c) reported workplace absenteeism (RCT: OR 0.92, 95% CI 0.57-1.50). In the surrogate exposure studies, N95 respirators were associated with less filter penetration, less face-seal leakage and less total inward leakage under laboratory experimental conditions, compared with surgical masks. INTERPRETATION Although N95 respirators appeared to have a protective advantage over surgical masks in laboratory settings, our meta-analysis showed that there were insufficient data to determine definitively whether N95 respirators are superior to surgical masks in protecting health care workers against transmissible acute respiratory infections in clinical settings.

Effectiveness of N95 respirators versus surgical masks in protecting health care workers from acute respiratory infection: a systematic review and meta-analysis.

Masks are widely discussed during the course of the ongoing COVID-19 pandemic. Most hospitals have implemented universal masking for their healthcare workers, and the Center for Disease Control currently advises even the general public to wear cloth masks when outdoors. The pertinent need for masks arises from plausible dissemination of the SARS-CoV-2 through close contacts, as well as the possibility of virus transmission from asymptomatic, pre-symptomatic, and mildly symptomatic individuals. Given current global shortages in personal protective equipment, the efficacy of various types of masks: N95 respirators, surgical masks, and cloth masks are researched. To accommodate limited supplies, techniques for extended use, reuse, and sterilization of masks are strategized. However, masks alone may not greatly slow down the COVID-19 pandemic unless they are coupled with adequate social distancing, diligent hand hygiene, and other proven preventive measures.

Comprehensive review of mask utility and challenges during the COVID-19 pandemic.

The main form of COVID-19 transmission is via oral-respiratory droplet contamination (droplet; very small drop of liquid) produced when individuals talk, sneeze or cough. In hospitals, health-care workers wear facemasks as a minimum medical droplet precaution to protect themselves. Due to the shortage of masks during the pandemic, priority is given to hospitals for their distribution. As a result, the availability/use of medical masks is discouraged for the public. However, given that asymptomatic individuals, not wearing masks within the public, can be highly contagious for COVID-19, prevention of environmental droplet contamination (EnDC) from coughing/sneezing/speech is fundamental to reducing transmission. As an immediate solution to promote public droplet safety, we assessed household textiles to quantify their potential as effective environmental droplet barriers (EDBs). The synchronized implementation of a universal community droplet reduction solution is discussed as a model against COVID-19. Using a bacterial-suspension spray simulation model of droplet ejection (mimicking a sneeze), we quantified the extent by which widely available clothing fabrics reduce the dispersion of droplets onto surfaces within 1.8m, the minimum distance recommended for COVID-19 social distancing. All textiles reduced the number of droplets reaching surfaces, restricting their dispersion to <30cm, when used as single layers. When used as double-layers, textiles were as effective as medical mask/surgical-cloth materials, reducing droplet dispersion to <10cm, and the area of circumferential contamination to ~0.3%. The synchronized implementation of EDBs as a community droplet reduction solution (i.e., face covers/scarfs/masks & surface covers) could reduce EnDC and the risk of transmitting or acquiring infectious respiratory pathogens, including COVID-19.

Textile Masks and Surface Covers - A 'Universal Droplet Reduction Model' Against Respiratory Pandemics

The role of masks and respirator protection against SARS-CoV-2

During the ongoing COVID-19 pandemic, healthcare professionals are at the forefront of managing the highly infectious coronavirus. As the most common route of transmission is via aerosols and droplet inhalation, it is critical for healthcare workers to have the correct personal protective equipment (PPE) including gowns, masks and goggles. Surgical masks are not effective in preventing the influenza and SARS, so they are unlikely to be able to resist contaminated aerosols from entering the respiratory system. Therefore, it is vital to use respirators which have been proven to offer better protection against droplets, aerosols and fluid penetration and which form a tight seal around the mouth and nose. Various types of respirators are used in healthcare settings, such as half-mask filtering facepiece respirators (FFRs) and powered air-purifying respirators (PAPRs). The most commonly used FFR is the N95 disposable respirator, which is tight fitting and has a 95% or above particle filtering efficiency for a median particle size of 0.3 µm. This review discusses respirators, their purpose, types, clinical efficiency and proper donning and doffing techniques.

Role of respirators in controlling the spread of novel coronavirus (COVID-19) amongst dental healthcare providers: a review

How to Produce Cheap and Easy Custom-Made Sterilizable Filtering Facepiece 2/3 Masks for Healthcare Providers During Pandemic COVID-19 Emergency.

What Type of Face Mask Is Appropriate for Everyone-Mask-Wearing Policy amidst COVID-19 Pandemic?

BACKGROUND: The novel coronavirus disease (COVID-19) has afflicted millions of people worldwide since its first case was reported in December 2019. Personal protective equipment (PPE) has been tailored accordingly, but as of April 2020, close to 10 000 health care workers in the United States have contracted COVID-19 despite wearing recommended PPE. As such, standard guidelines for PPE may be inadequate for the health care worker performing high-risk aerosolizing procedures such as endotracheal intubation. In this brief technical report, we describe the integration of an orthopedic hood cover as an item for full barrier protection against COVID-19 transmission. TECHNICAL DESCRIPTION: The Coronavirus Airway Task Force at Virginia Commonwealth University Medical Center approved this initiative and went live with the full barrier suit during the last week of March 2020. The PPE described in this report includes a Stryker T4 Hood, normally used in conjunction with the Stryker Steri-Shield T4 Helmet. Instead of the helmet, the hood is secured to the head via a baseball cap and binder clip. This head covering apparatus is to be used as an accessory to other PPE items that include an N95 mask, waterproof gown, and disposable gloves. The motor ventilation system is not used in order to prevent airborne viral entry into the hood. DISCUSSION: An advantage of the full barrier suit is an additional layer of droplet protection during intubation. The most notable disadvantage is the absence of a ventilation system within the hood covering. CONCLUSION: Modification of existing PPE may provide protection for health care workers during high-risk aerosolizing procedures such as endotracheal intubation. Although the integration of this medical equipment meets the immediate needs of an escalating crisis, further innovation is on the horizon. More research is needed to confirm the safety of modified PPE.

Utilization of an Orthopedic Hood as Personal Protective Equipment for Intubation of Coronavirus Patients: a Brief Technical Report

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has led to personal protective equipment (PPE) shortages, requiring mask reuse or improvisation. We provide a review of medical-grade facial protection (surgical masks, N95 respirators and face shields) for healthcare workers, the safety and efficacy of decontamination methods, and the utility of alternative strategies in emergency shortages or resource-scarce settings. METHODS: We conducted a scoping review of PubMed and grey literature related to facial protection and potential adaptation strategies in the setting of PPE shortages (January 2000 to March 2020). Limitations included few COVID-19-specific studies and exclusion of non-English language articles. We conducted a narrative synthesis of the evidence based on relevant healthcare settings to increase practical utility in decision-making. RESULTS: We retrieved 5462 peer-reviewed articles and 41 grey literature records. In total, we included 67 records which met inclusion criteria. Compared with surgical masks, N95 respirators perform better in laboratory testing, may provide superior protection in inpatient settings and perform equivalently in outpatient settings. Surgical mask and N95 respirator conservation strategies include extended use, reuse or decontamination, but these strategies may result in inferior protection. Limited evidence suggests that reused and improvised masks should be used when medical-grade protection is unavailable. CONCLUSION: The COVID-19 pandemic has led to critical shortages of medical-grade PPE. Alternative forms of facial protection offer inferior protection. More robust evidence is required on different types of medical-grade facial protection. As research on COVID-19 advances, investigators should continue to examine the impact on alternatives of medical-grade facial protection.

Facial protection for healthcare workers during pandemics: a scoping review

The current pandemic of COVID-19 has lead to conflicting opinions on whether wearing facemasks outside of health care facilities protects against the infection. To better understand the value of wearing facemasks we undertook a rapid systematic review of existing scientific evidence about development of respiratory illness, linked to use of facemasks in community settings. METHODS: We included all study designs. There were 31 eligible studies (including 12 RCTs). Narrative synthesis and random-effects meta-analysis of attack rates for primary and secondary prevention in 28 studies were performed. Results were reported by design, setting and type of face barrier in primary prevention, and by who wore the facemask (index patient or well contacts) in secondary prevention trials. The preferred outcome was influenza-like illness (ILI) but similar outcomes were pooled with ILI when ILI was unavailable. GRADE quality assessment was based on RCTs with support from observational studies. RESULTS: Where specific information was available, most studies reported about use of medical grade (surgical paper masks). In 3 RCTs, wearing a facemask may very slightly reduce the odds of developing ILI/respiratory symptoms, by around 6% (OR 0.94, 95% CI 0.75 to 1.19, I2 29%, low certainty evidence). Greater effectiveness was suggested by observational studies. When both house-mates and an infected household member wore facemasks the odds of further household members becoming ill may be modestly reduced by around 19% (OR 0.81, 95%CI 0.48 to 1.37, I 2 45%, 5 RCTs, low certainty evidence). The protective effect was very small if only the well person(OR 0.93, 95% CI 0.68 to 1.28, I2 11%, 2 RCTs, low uncertainty evidence) or the infected person wore the facemask (very low certainty evidence). DISCUSSION: Based on the RCTs we would conclude that wearing facemasks can be very slightly protective against primary infection from casual community contact, and modestly protective against household infections when both infected and uninfected members wear facemasks. However, the RCTs often suffered from poor compliance and controls using facemasks. Across observational studies the evidence in favour of wearing facemasks was stronger. We expect RCTs to under-estimate the protective effect and observational studies to exaggerate it. The evidence is not sufficiently strong to support widespread use of facemasks as a protective measure against COVID-19. However, there is enough evidence to support the use of facemasks for short periods of time by particularly vulnerable individuals when in transient higher risk situations. Further high quality trials are needed to assess when wearing a facemask in the community is most likely to be protective.

Facemasks and similar barriers to prevent respiratory illness such as COVID-19: A rapid systematic review

Pandemics such as influenza, smallpox, and plague have caused the loss of hundreds of millions of lives and have occurred for many centuries. Fortunately, they have been largely eliminated by the use of vaccinations and drugs. More recently, Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome (MERS), and now Coronavirus Disease 2019 (COVID-19) have arisen, and given the current absence of highly effective approved vaccines or drugs, brute-force approaches involving physical barriers are being used to counter virus spread. A major basis for physical protection from respiratory infections is eye, nose, and mouth protection. However, eye protection with goggles is problematic due to “fogging”, while nose/mouth protection is complicated by the breathing difficulties associated with non-valved respirators. Here, we give a brief review of the origins and development of face masks and eye protection to counter respiratory infections on the basis of experiments conducted 100 years ago, work that was presaged by the first use of personal protective equipment, “PPE”, by the plague doctors of the 17(th) Century. The results of the review lead to two conclusions: first, that eye protection using filtered eye masks be used to prevent ocular transmission; second, that new, pre-filtered, valved respirators be used to even more effectively block viral transmission.

COVID-19 and Other Pandemics: How Might They Be Prevented?

Masks and COVID-19

Face masks - a sustainable measure to mitigate COVID-19.

Mask wearing to complement social distancing and save lives during COVID-19.

Facial mask: A necessity to beat COVID-19

The coronavirus disease 2019 (COVID-19) pandemic is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which can be transmitted via respiratory secretions. Since there are currently no specific therapeutics or vaccines available against the SARS-CoV-2, the commen nonpharmaceutical interventions (NPIs) are still the main measures to curb the COVID-19 epidemic. Face mask wearing is one important measure to suppress the pandemic. In order to know how efficient is face mask wearing in reducing the pandemic even with low efficiency non-professional face masks, we exploit physical abstraction to model the non-professional face masks made from cotton woven fabrics and characterize them by a parameter virus penetration rate (VPR){gamma}. Monte Carlo simulations exhibit that the effective reproduction number R of COVID-19 or similar pandemics can be approximately reduced by factor {gamma}4 with respect to the basic reproduction number R0,if the face masks with 70% <{gamma}< 90% are universally applied for the entire network. Furthermore, thought experiments and practical exploitation examples in country-level and city-level are enumerated and discussed to support our discovery in this study and indicate that the outbreak of a COVID-19 like pandemic can be even suppressed by the low efficiency non-professional face masks.

How Efficient Can Non-Professional MasksSuppress COVID-19 Pandemic?

Health professions preventing and controlling Coronavirus Disease 2019 are prone to skin and mucous membrane injury, which may cause acute and chronic dermatitis, secondary infection and aggravation of underlying skin diseases. This is a consensus of Chinese experts on protective measures and advice on hand-cleaning- and medical-glove-related hand protection, mask- and goggles-related face protection, UV-related protection, eye protection, nasal and oral mucosa protection, outer ear, and hair protection. It is necessary to strictly follow standards of wearing protective equipment and specification of sterilizing and cleaning. Insufficient and excessive protection will have adverse effects on the skin and mucous membrane barrier. At the same time, using moisturizing products is highly recommended to achieve better protection.

Consensus of Chinese experts on protection of skin and mucous membrane barrier for health-care workers fighting against coronavirus disease 2019

In December 2019, transmission of the novel coronavirus (SARS-CoV-2) that causes coronavirus disease 2019(COVID-19) occurred in Wuhan, China1 .And later the virus began to be transmitted from person to person2 .Face masks are a type of personal protective equipment used to prevent the spread of respiratory infections，it may be effective at helping prevent transmission of respiratory viruses and bacteria3 .Here, we share a case of face masks are be used to prevent the transmission of COVID-19 infection.

COVID‐19: Face masks and human‐to‐human transmission

Abstract Objective We compared the efficacy of medical masks (MM) and N95 respirators (N95) in preventing bacterial colonization/infection in healthcare workers (HCWs). Methods A cluster randomized clinical trial (RCT) of 1441 hospital HCWs randomized to medical masks or N95 respirators, and compared to 481 control HCWs, was performed in Beijing, China, during the winter season of 2008–2009. Participants were followed for development of clinical respiratory illness (CRI). Symptomatic subjects were tested for Streptococcus pneumoniae, Bordetella pertussis, Chlamydia pneumoniae, Mycoplasma pneumoniae or Haemophilus influenza type B by multiplex polymerase chain reaction (PCR). Results The rate of bacterial colonization was 2.8% in the N95 group (p=0.02), 5.3% among medical mask users (p<0.01) and 7.5% among the controls (p=0.16). N95 respirators were significantly protective (adjusted RR 0.34, 95% CI: 0.21–0.56) against bacterial colonization. Co-infections of two bacteria or a virus and bacteria occurred in up to 3.7% of HCWs, and were significantly lower in the N95 arm. Conclusions N95 respirators were significantly protective against bacterial colonization, co-colonization and viral-bacterial co-infection. We showed that dual respiratory virus or bacterial-viral co-infections can be reduced by the use of N95 respirators. This study has occupational health and safety implications for health workers.

Efficacy of face masks and respirators in preventing upper respiratory tract bacterial colonization and co-infection in hospital healthcare workers

We live in extraordinary times, where COVID-19 pandemic has brought the whole world to a screeching halt. Tensions and contradictions that surround the pandemic ridden world include the availability, and the lack thereof, various facial protection measures to mitigate the viral spread. Here, we comprehensively explore the different types of facial protection measures, including masks, needed both for the public and the healthcare workers (HCW). We discuss the anatomy, the critical issues of disinfection and reusability of masks, the alternative equipment available for the protection of the facial region from airborne diseases, such as face shields and powered air-purifying respirators (PAPR), and the skin health impact of prolonged wearing of facial protection by HCW. Clearly, facial protection, either in the form of masks or alternates, appears to have mitigated the pandemic as seen from the minimal COVID-19 spread in countries where public mask wearing is strictly enforced. On the contrary, the healthcare systems, that appear to have been unprepared for emergencies of this nature, should be appropriately geared to handle the imbalance of supply and demand of personal protective equipment including face masks. These are two crucial lessons we can learn from this tragic experience.

Facial protection in the era of COVID-19: A narrative review

Simple plastic face shields have many advantages compared to regular medical masks. They are easily cleaned for reuse and comfortable to wear. In light of the spreading COVID-19 pandemic, the potential of face shields as a substitution for medical masks, as a recommendation to the general population, was tested. Testing the efficacy of the protective equipment utilized a cough simulator that was carefully tuned to replicate human cough in terms of droplet size distribution and outlet velocity. The tested protective equipment was worn on a manikin head simulating human breathing. An Aerodynamic Particle Sizer (APS) was used to analyze the concentration and size distribution of small particles that reach the manikin head respiration pathways. Additionally, Water sensitive papers were taped over and under the tested protective equipment, and were subsequently photographed and analyzed. For droplets larger than 3m by diameter, the efficiency of shields to block cough droplets was found to be comparable to that of regular medical masks, with enhanced protection on face parts the mask does not cover. Additionally, for finer particles, of the order 0.3 to few microns, a shield was found to perform even better, blocking about 10 times more fine particles than the medical mask. This implies that for the general population that is not intendedly exposed to confirmed infected individuals, recommending the use of face shields as an alternative to medical masks should be considered.

Examining the protection efficacy of face shields against cough aerosol droplets using water sensitive papers

Mandates for mask use in public during the recent COVID-19 pandemic, worsened by global shortage of commercial supplies, have led to widespread use of homemade masks and mask alternatives. It is assumed that wearing such masks reduces the likelihood for an infected person to spread the disease, but many of these mask designs have not been tested in practice. We have applied a simple optical measurement method to evaluate the efficacy of masks to reduce the transmission of respiratory droplets during regular speech. We compare a variety of commonly available mask types and observe that some mask types approach the performance of standard surgical masks, while some mask alternatives, such as neck fleece or bandanas, offer very little protection. Our measurement setup is inexpensive and can be built and operated by non-experts, allowing for rapid evaluation of mask performance during speech, sneezing, or coughing.

Low-cost measurement of facemask efficacy for filtering expelled droplets during speech

We live in extraordinary times, where COVID-19 pandemic has brought the whole world to a screeching halt. Tensions and contradictions that surround the pandemic ridden world include the availability, and the lack thereof, various facial protection measures to mitigate the viral spread. Here, we comprehensively explore the different type of facial protection measures, including masks, needed both for the pubic and the health care workers (HCW). We discuss the anatomy, the critical issues of disinfection and reusability of masks, the alternative equipment available for the protection of the facial region from airborne diseases, such as face shields and powered air purifying respirators (PAPR), and the skin-health impact of prolonged wearing of facial protection by HCW. Clearly, facial protection, either in the form of masks or alternates, appears to have mitigated the pandemic as seen from the minimal COVID-19 spread in countries where public mask wearing is strictly enforced. On the contrary, the healthcare systems, that appear to have been unprepared for emergencies of this nature, should be appropriately geared to handle the imbalance of supply and demand of personal protective equipment including face masks. These are two crucial lessons we can learn from this tragic experience.

Facial protection in the era of COVID-19: a narrative review

During the ongoing COVID‐19 pandemic, healthcare professionals are at the forefront of managing the highly infectious coronavirus. As the most common route of transmission is via aerosols and droplet inhalation, it is critical for healthcare workers to have the correct personal protective equipment (PPE) including gowns, masks and goggles. Surgical masks are not effective in preventing the influenza and SARS, so they are unlikely to be able to resist contaminated aerosols from entering the respiratory system. Therefore, it is vital to use respirators which have been proven to offer better protection against droplets, aerosols and fluid penetration and which form a tight seal around the mouth and nose. Various types of respirators are used in healthcare settings, such as half‐mask filtering facepiece respirators (FFRs) and powered air‐purifying respirators (PAPRs). The most commonly used FFR is the N95 disposable respirator, which is tight fitting and has a 95% or above particle filtering efficiency for a median particle size of 0.3 µm. This review discusses respirators, their purpose, types, clinical efficiency and proper donning and doffing techniques.

Role of respirators in controlling the spread of novel coronavirus (COVID‐19) amongst dental healthcare providers: a review

The medical community agrees that breathborne infectious materials can be spread with exhaled aerosols and that asymptomatic people, i.e., those showing no symptoms, could be unknowingly infectious. With the current worldwide pandemic of the respiratory coronavirus disease 2019 (COVID-19), various health bodies and governments are recommending that the population wear some form of mask or improvised facial covers while out in public in an effort to reduce the spread of disease . The general concept is that more accessible masks or mask-like materials (scarves, bandanas, etc.) could serve to reduce the amount of infectious aerosol from infected people, and reduce the viral load in the environment. This editorial addresses the underlying scientific rationale that such inexpensive or improvised could indeed serve to reduce the emissions of infectious aerosol by the mechanism of surface adhesion and particle kinetics in addition to the filtration effect.

The scientific rationale for the use of simple masks or improvised facial coverings to trap exhaled aerosols and possibly reduce the breathborne spread of COVID-19

Background: There is paucity of evidence on the effectiveness of facemask use in COVID-19 in community settings. Objectives: We aimed to estimate the effectiveness of facemask use alone or along with hand hygiene in community settings in reducing the transmission of viral respiratory illness. Methods: We searched PubMed and Embase for randomized controlled trials on facemask use in community settings to prevent viral respiratory illnesses published up to April 25, 2020. Two independent reviewers were involved in synthesis of data. Data extraction and risk-of-bias assessment were done in a standard format from the selected studies. Outcome data for clinically diagnosed or self-reported influenza-like illness (ILI) was recorded from individual studies. Pooled effect size was estimated by random-effects model for "facemask only versus control" and "facemask plus hand hygiene versus control." Results: Of the 465 studies from PubMed and 437 studies from Embase identified from our search, 9 studies were included in qualitative synthesis and 8 studies in quantitative synthesis. Risk of bias was assessed as low (n = 4), medium (n = 3), or high (n = 1) risk. Interventions included using a triple-layered mask alone or in combination with hand hygiene. Publication bias was not significant. There was no significant reduction in ILI either with facemask alone (n = 5, pooled effect size: -0.17; 95% confidence interval [CI]: -0.43-0.10; P = 0.23; I2 = 10.9%) or facemask with handwash (n = 6, pooled effect size: (n=6, pooled effect size: -0.09; 95% CI: -0.58 to 0.40; P = 0.71, I2 = 69.4%). Conclusion: : Existing data pooled from randomized controlled trials do not reveal a reduction in occurrence of ILI with the use of facemask alone in community settings.

Facemasks for prevention of viral respiratory infections in community settings: A systematic review and meta-analysis

Background There is paucity of evidence on the effectiveness of facemask use in COVID-19 in community settings. Objectives We aimed to estimate the effectiveness of facemask use alone or along with hand hygiene in community settings in reducing the transmission of viral respiratory illness. Methods We searched PubMed and Embase for randomized controlled trials on facemask use in community settings to prevent viral respiratory illnesses published up to April 25, 2020. Two independent reviewers were involved in synthesis of data. Data extraction and risk-of-bias assessment were done in a standard format from the selected studies. Outcome data for clinically diagnosed or self-reported influenza-like illness (ILI) was recorded from individual studies. Pooled effect size was estimated by random-effects model for "facemask only versus control" and "facemask plus hand hygiene versus control." Results Of the 465 studies from PubMed and 437 studies from Embase identified from our search, 9 studies were included in qualitative synthesis and 8 studies in quantitative synthesis. Risk of bias was assessed as low (n = 4), medium (n = 3), or high (n = 1) risk. Interventions included using a triple-layered mask alone or in combination with hand hygiene. Publication bias was not significant. There was no significant reduction in ILI either with facemask alone (n = 5, pooled effect size: -0.17; 95% confidence interval [CI]: -0.43-0.10; P = 0.23; I2 = 10.9%) or facemask with handwash (n = 6, pooled effect size: (n=6, pooled effect size: -0.09; 95% CI: -0.58 to 0.40; P = 0.71, I2 = 69.4%). Conclusion : Existing data pooled from randomized controlled trials do not reveal a reduction in occurrence of ILI with the use of facemask alone in community settings.

Facemasks for prevention of viral respiratory infections in community settings: A systematic review and meta-analysis.

Coronavirus, the virus that caused the global pandemic at the beginning of 2020 and affected millions across the globe, presented as an enormous challenge to health care providers around the world. With increasing numbers of infected patients presenting daily, health care workers are struggling to take effective measures to protect themselves from transmission against the highly contagious coronavirus. This case helps us understand the implications of coronavirus-infected patients on the health care providers directly responsible for the management of these patients and the relative efficacy of different types of respiratory protective equipment mainly N95 masks and surgical masks in preventing the spread of infection among those at the front lines providing care.

COVID-19 and the Efficacy of Different Types of Respiratory Protective Equipment Used by Health Care Providers in a Health Care Setting