BACKGROUND: Verifying the fit of disposable N95/P2 half-face respirators is critical. There are currently no objective ways to evaluate the implementation when used. Previously, we showed that only 26% of healthcare workers achieve appropriate fit at the point of use.
METHODS: 657 quantitative fit tests were conducted on 166 subjects, using four different respirator styles. Randomization was performed; controls employing standard \'fit-check\' and intervention using a custom built infra-red video kiosk. Primary outcome was passing rates of quantitative fit, with secondary outcomes of respirator type, gender, race, and previous experience.
RESULTS: Intervention demonstrated significantly higher pass rate (50.6%) compared to controls (30.8%). The odds of passing with IR Kiosk compared to control was 2.3 (OR 2.3 95%CI 1.8 to 2.9, p<0.001). Duckbill style improved the greatest (OR 4.1 95%CI 2.1 to 7.9, p<0.001), and Tri-fold also showing substantial benefit (OR 2.66 95%CI 1.4 to 5.2, p<0.001). Gender and race did not influence the outcomes when using the kiosk, nor did previous experience.
CONCLUSIONS: A custom point of use kiosk improved the odds of achieving a satisfactory fit of common respirator styles, independent of participant demographics. These findings open the door to addressing a critical gap in respiratory protection programs by providing individual assessment and interventions that improve worker safety at the time of highest risk.
UNASSIGNED: The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to their containing information that could compromise the privacy of research participants.

BACKGROUND: Now and in the future, airborne diseases such as COVID-19 could become uncontrollable and lead the world into lockdowns. Finding alternatives to lockdowns, which limit individual freedoms and cause enormous economic losses, is critical.
OBJECTIVE: The purpose of this study was to assess the feasibility of achieving a society or a nation that does not require lockdown during a pandemic due to airborne infectious diseases through the mass production and distribution of high-performance, low-cost, and comfortable powered air purifying respirators (PAPRs).
METHODS: The feasibility of a social system using PAPR as an alternative to lockdown was examined from the following perspectives: first, what PAPRs can do as an alternative to lockdown; second, how to operate a social system utilizing PAPR; third, directions of improvement of PAPR as an alternative to lockdown; and finally, balancing between efficiency of infection control and personal freedom through the use of Internet of Things (IoT).
RESULTS: PAPR was shown to be a possible alternative to lockdown through the reduction of airborne and droplet transmissions and through a temporary reduction of infection probability per contact. A social system in which individual constraints imposed by lockdown are replaced by PAPRs was proposed, and an example of its operation is presented in this paper. For example, the government determines the type and intensity of the lockdown and activates it. At that time, the government will also indicate how PAPR can be substituted for the different activity and movement restrictions imposed during a lockdown, for example, a curfew order may be replaced with the permission to go outside if wearing a PAPR. The following 7 points were raised as directions for improvement of PAPR as an alternative method to lockdown: flow optimization, precise differential pressure control, design improvement, maintenance method, variation development such as booth type, information terminal function, and performance evaluation method. In order to achieve the effectiveness and efficiency in controlling the spread of infection and the individual freedom at a high level in a social system that uses PAPRs as an alternative to lockdown, it was considered effective to develop a PAPR wearing rate network management system utilizing IoT.
CONCLUSIONS: This study shows that using PAPR with infection control ability and with less economic and social damage as an alternative to nationwide lockdown is possible during a pandemic due to airborne infectious diseases. Further, the efficiency of the government\'s infection control and each citizen\'s freedom can be balanced by using the PAPR wearing rate network management system utilizing an IoT system.

BACKGROUND: Tight-fitting masks and respirators, in manikin studies, improved aerosol source control compared to loose-fitting masks. Whether this translates to humans is not known.
METHODS: We compared efficacy of masks (cloth and surgical) and respirators (KN95 and N95) as source control for SARS-CoV-2 viral load in exhaled breath of volunteers with COVID-19 using a controlled human experimental study. Volunteers (N = 44, 43% female) provided paired unmasked and masked breath samples allowing computation of source-control factors.
RESULTS: All masks and respirators significantly reduced exhaled viral load, without fit tests or training. A duckbill N95 reduced exhaled viral load by 98% (95% CI: 97%-99%), and significantly outperformed a KN95 (p < 0.001) as well as cloth and surgical masks. Cloth masks outperformed a surgical mask (p = 0.027) and the tested KN95 (p = 0.014).
CONCLUSIONS: These results suggest that N95 respirators could be the standard of care in nursing homes and healthcare settings when respiratory viral infections are prevalent in the community and healthcare-associated transmission risk is elevated.
BACKGROUND: Defense Advanced Research Projects Agency, National Institute of Allergy and Infectious Diseases, Centers for Disease Control and Prevention, the Bill & Melinda Gates Foundation, and The Flu Lab.

SUMMARYThis narrative review and meta-analysis summarizes a broad evidence base on the benefits-and also the practicalities, disbenefits, harms and personal, sociocultural and environmental impacts-of masks and masking. Our synthesis of evidence from over 100 published reviews and selected primary studies, including re-analyzing contested meta-analyses of key clinical trials, produced seven key findings. First, there is strong and consistent evidence for airborne transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and other respiratory pathogens. Second, masks are, if correctly and consistently worn, effective in reducing transmission of respiratory diseases and show a dose-response effect. Third, respirators are significantly more effective than medical or cloth masks. Fourth, mask mandates are, overall, effective in reducing community transmission of respiratory pathogens. Fifth, masks are important sociocultural symbols; non-adherence to masking is sometimes linked to political and ideological beliefs and to widely circulated mis- or disinformation. Sixth, while there is much evidence that masks are not generally harmful to the general population, masking may be relatively contraindicated in individuals with certain medical conditions, who may require exemption. Furthermore, certain groups (notably D/deaf people) are disadvantaged when others are masked. Finally, there are risks to the environment from single-use masks and respirators. We propose an agenda for future research, including improved characterization of the situations in which masking should be recommended or mandated; attention to comfort and acceptability; generalized and disability-focused communication support in settings where masks are worn; and development and testing of novel materials and designs for improved filtration, breathability, and environmental impact.

UNASSIGNED: Wearing protective face masks and respirators has been a necessity to reduce the transmission rate of respiratory viruses since the outbreak of the coronavirus (COVID-19) disease. Nevertheless, the outbreak has revealed the need to develop efficient air filter materials and innovative anti-microbial protectives. Nanofibrous facemasks, either loaded with antiviral nanoparticles or not, are very promising personal protective equipment (PPE) against pandemic respiratory viruses.
UNASSIGNED: In this review, multiple types of face masks and respirators are discussed as well as filtration mechanisms of particulates. In this regard, the limitations of traditional face masks were summarized and the advancement of nanotechnology in developing nanofibrous masks and air filters was discussed. Different methods of preparing nanofibers were explained. The various approaches used for enhancing nanofibrous face masks were covered.
UNASSIGNED: Although wearing conventional face masks can limit viral infection spread to some extent, the world is in great need for more protective face masks. Nanofibers can block viral particles efficiently and can be incorporated into face masks in order to enhance their filtration efficiency. Also, we believe that other modifications such as addition of antiviral nanoparticles can significantly increase the protection power of facemasks.

BACKGROUND: The existing respiratory fit test panels (RFTPs) are based on Bivariate and Principal Component Analysis (PCA) which utilise American and Chinese head and facial dimensions. As RFTPs based on local facial anthropometric data for Malaysia are not available, this study was conducted with the aim to develop new RFTPs using Malaysian data.
METHODS: A cross-sectional study was conducted across Malaysia among 3,324 participants of the study of National Health and Morbidity Survey 2020 aged 18 and above. Ten head and facial dimensions were measured. Face length and face width were used to construct bivariate facial panel, whereas the scores from the first two PCA were used to develop the PCA panel.
RESULTS: This study showed that Malaysians have the widest upper limit for facial width. It also found that three factors could be reduced from the PCA analysis. However only 2 factors were selected with PCA 1 representing head and facial size and PCA 2 representing facial shape. Our bivariate panel could accommodate 95.0% of population, while our PCA panel accommodated 95.6%.
CONCLUSIONS: This was the first study to use Malaysian head and facial anthropometry data to create bivariate and PCA panels. Respirators constructed using these panels are likely to fit ≥ 95.0% of Malaysia\'s population.

BACKGROUND: Owing to shortage of surgical and N95 filtering facepiece respirators (FFRs) during the COVID-2019 pandemic, various masks were developed to prevent infection. This study aimed to examine the inward leakage rate (ILR) of sealed face masks and modified surgical masks using a quantitative fit test and compared it with the ILR of unmodified N95 FFRs.
METHODS: We conducted paired comparisons of ILRs of bent nose-fit wire masks, double masks, and N95 FFRs from October to December 2021. To measure the protective effectiveness of masks, participants wore masks, and the number of particles outside and inside the mask were measured. The ILR was based on the percentage of particles entering the mask using a fit tester.
RESULTS: We enrolled 54 participants (20 men and 34 women) in this study. The median ILR for surgical masks without and with a W-shaped bend in the nose-fit wire were 96.44% and 50.82%, respectively. The nose-fit wire adjustment reduced the ILR of surgical masks by a mean of 28.57%, which was significantly lower than the ILR without adjustment (P < 0.001). For double masks, with surgical or polyurethane masks on top of the W-shaped mask, the ILR did not differ significantly from that of N95. Although the filtration performance of double surgical masks matched that of N95 masks, their ILR was notably higher, indicating that double masks do not provide equivalent protection.
CONCLUSIONS: Wearing N95 masks alone is effective in many cases. However, surgical mask modifications do not guarantee consistent effectiveness. Properly selected, sealed masks with a good fit overcome leakage, emphasizing their crucial role. Without evidence, mask-wearing may lead to unexpected infections. Education based on quantitative data is crucial for preventing adverse outcomes.

BACKGROUND: Health care workers (HCWs) in Canada have endured difficult conditions during the COVID-19 pandemic. Many worked long hours while attending to patients in a contagious environment. This introduced an additional burden that may have contributed to worsened mental health conditions.
OBJECTIVE: In this study, we examine the factors associated with worsened mental health conditions of HCWs as compared to before the start of the pandemic.
METHODS: We use data from a survey of HCWs by Statistics Canada. A regression model is used to estimate the odds ratios (ORs) of worsened mental health after the start of the pandemic. The estimated odds ratio (OR) is associated with different independent variables that include demographics (age, sex, immigration status, and geographic area), occupational factors (work status, occupational group, and exposure category), and different access levels to personal protective equipment (PPE).
RESULTS: Of 18,139 eligible participants surveyed, 13,990 (77.1%) provided valid responses. We found that HCWs younger than 35 years old were more likely (OR 1.14, 95% CI 1.03-1.27; P=.01) to exhibit worsened mental health as compared to the reference group (35-44 years old). As for sex, male HCWs were less likely (OR 0.76, 95% CI 0.67-0.86; P<.001) to exhibit worsened mental health as compared to female HCWs. Immigrant HCWs were also less likely (OR 0.57, 95% CI 0.51-0.64; P<.001) to exhibit worsened mental health as compared to nonimmigrant HCWs. Further, HCWs working in Alberta had the highest likelihood of exhibiting worsened mental health as compared to HCWs working elsewhere (Atlantic provinces, Quebec, Manitoba, Saskatchewan, Ontario, British Columbia, and Northern Territories). Frontline workers were more likely (OR 1.26, 95% CI 1.16-1.38; P<.001) to exhibit worsened mental health than nonfrontline HCWs. Part-time HCWs were less likely (OR 0.85, 95% CI 0.76-0.93; P<.001) to exhibit worsened mental health than full-time HCWs. HCWs who reported encountering COVID-19 cases were more likely (OR 1.55, 95% CI 1.41-1.70; P<.001) to exhibit worsened mental health as compared to HCWs who reported no contact with the disease. As for PPE, HCWs who never had access to respirators, eye protection, and face shields are more likely to exhibit worsened mental health by 1.31 (95% CI 1.07-1.62; P<.001), 1.51 (95% CI 1.17-1.96; P<.001), and 1.41 (95% CI 1.05-1.92; P=.02) than those who always had access to the same PPE, respectively.
CONCLUSIONS: Different HCW groups experienced the pandemic differently based on their demographic and occupational backgrounds as well as access to PPE. Such findings are important to stakeholders involved in the planning of personalized support programs and aid mental health mitigation in future crises. Certain groups require more attention.

This rapid systematic review of evidence asks whether (i) wearing a face mask, (ii) one type of mask over another and (iii) mandatory mask policies can reduce the transmission of SARS-CoV-2 infection, either in community-based or healthcare settings. A search of studies published 1 January 2020-27 January 2023 yielded 5185 unique records. Due to a paucity of randomized controlled trials (RCTs), observational studies were included in the analysis. We analysed 35 studies in community settings (three RCTs and 32 observational) and 40 in healthcare settings (one RCT and 39 observational). Ninety-five per cent of studies included were conducted before highly transmissible Omicron variants emerged. Ninety-one per cent of observational studies were at \'critical\' risk of bias (ROB) in at least one domain, often failing to separate the effects of masks from concurrent interventions. More studies found that masks (n = 39/47; 83%) and mask mandates (n = 16/18; 89%) reduced infection than found no effect (n = 8/65; 12%) or favoured controls (n = 1/65; 2%). Seven observational studies found that respirators were more protective than surgical masks, while five found no statistically significant difference between the two mask types. Despite the ROB, and allowing for uncertain and variable efficacy, we conclude that wearing masks, wearing higher quality masks (respirators), and mask mandates generally reduced SARS-CoV-2 transmission in these study populations. This article is part of the theme issue \'The effectiveness of non-pharmaceutical interventions on the COVID-19 pandemic: the evidence\'.

Correctly fitting N95 filtering facepiece respirators (FFRs) have become increasingly important in health care throughout the COVID-19 pandemic. We evaluated the hypothesis that personalized 3D-printed frames could improve N95 FFRs quantitative fit test pass rates and test scores in health care workers (HCWs). HCWs were recruited at a tertiary hospital in Adelaide, Australia (ACTRN 12622000388718). A mobile iPhone camera + app was used to produce 3D scans of volunteers\' faces, which were then imported into a software program to produce personalized virtual scaffolds suited to each user\'s face and their unique anatomical features. These virtual scaffolds were printed on a commercially available 3D printer, producing plastic (and then silicone-coated, biocompatible) frames that can be fitted inside existing hospital supply N95 FFR. The primary endpoint was improved pass rates on quantitative fit testing, comparing participants wearing an N95 FFR alone (control 1) with participants wearing the frame + N95 FFR (intervention 1). The secondary endpoint was the fit factor (FF) in these groups, and R-COMFI respirator comfort and tolerability survey scores. N = 66 HCWs were recruited. The use of intervention 1 increased overall fit test pass rates to 62/66 (93.8%), compared to 27/66 (40.9%) for controls. (OR for pFF pass 20.89 (95%CI: 6.77, 64.48, p < 0.001.) Average FF increased, with the use of intervention 1-179.0 (95%CI: 164.3,193.7), compared to 85.2 (95%CI: 70.4,100.0) with control 1. Pass rates and FF were improved with intervention 1 compared to control 1 for all stages of the fit-test: bending, talking, side-to-side, and up-down motion. (p < 0.001 all stages). Tolerability and comfort of the frame were evaluated with the validated R-COMFI respirator comfort score, showing improvement with the frame compared to N95 FFR alone (p = 0.006). Personalized 3D-printed face frames decrease leakage, improve fit testing pass rates and FF, and provide improved comfort compared to the N95 FFR alone. Personalized 3D-printed face frames represent a rapidly scalable new technology to decrease FFR leakage in HCW and potentially the wider population.