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

Microfluidics-based condensation bioaerosol sampler for multipoint airborne virus monitoring

To facilitate rapid monitoring of airborne viruses, they must be collected with high efficiency and concentrated in a small volume of a liquid sample. In addition, the development of low-cost miniaturized samplers is essential for multipoint monitoring. Thus, in an attempt to fulfill these requirements, this study developed a microfluidic condensation bioaerosol sampler (MCBS). The developed sampler comprised two parts: a virus growth section and a virus droplet-to-liquid sample conversion section, each of which was fabricated on a chip using microfluidic technology. The condensation nucleus growth technique used in the virus growth section grew nanometer-sized airborne viruses into micro-sized droplets, making it possible to collection of viruses easier and with high efficiency. In addition, the virus droplet-to-liquid sample conversion section controlled the transport of droplets based on electrowetting technology. This enabled the collected airborne viruses to be concentrated in tens of microliters of the liquid sample. To evaluate the performance of both the sections, the virus dropletization, virus collection efficiency, and virus droplet-to-liquid sample conversion efficiency were evaluated through quantitative experiments. H1N1 and HCOV-229E viruses were used to conduct quantitative experiments on MCBS. We could obtain virus liquid samples with at 72.8- and 89.9-times higher concentration through 1:1 evaluation with a commercial sampler. Thus, the developed sampler facilitated efficient collection and concentration of airborne viruses in a compact, cost-effective manner. This is expected to facilitate rapid and accurate multipoint monitoring of viral aerosols.

Epidemic modelling suggests that in specific circumstances masks may become more effective when fewer contacts wear them

BACKGROUND

The effectiveness of non-pharmaceutical interventions to control the spread of SARS-CoV-2 depends on many contextual factors, including adherence. Conventional wisdom holds that the effectiveness of protective behaviours, such as wearing masks, increases with the number of people who adopt them. Here we show in a simulation study that this is not always true.

METHODS

We use a parsimonious network model based on the well-established empirical facts that adherence to such interventions wanes over time and that individuals tend to align their adoption strategies with their close social ties (homophily).

RESULTS

When these assumptions are combined, a broad dynamic regime emerges in which the individual-level reduction in infection risk for those adopting protective behaviour increases as adherence to protective behaviour decreases. For instance, at 10 % coverage, we find that adopters face nearly a 30 % lower infection risk than at 60 % coverage. Based on surgical mask effectiveness estimates, the relative risk reduction for masked individuals ranges from 5 % to 15 %, or a factor of three. This small coverage effect occurs when the outbreak is over before the pathogen is able to invade small but closely knit groups of individuals who protect themselves.

CONCLUSIONS

Our results confirm that lower coverage reduces protection at the population level while contradicting the common belief that masking becomes ineffective at the individual level as more people drop their masks.

Association of institutional masking policies with healthcare-associated SARS-CoV-2 infections in Swiss acute care hospitals during the BA.4/5 wave (CH-SUR study): a retrospective observational study

BACKGROUND

In the initial phase of the SARS-CoV-2 pandemic, masking has been widely accepted in healthcare institutions to mitigate the risk of healthcare-associated infection. Evidence, however, is still scant and the role of masks in preventing healthcare-associated SARS-CoV-2 acquisition remains unclear.We investigated the association of variation in institutional mask policies with healthcare-associated SARS-CoV-2 infections in acute care hospitals in Switzerland during the BA.4/5 2022 wave.

METHODS

SARS-CoV-2 infections in hospitalized patients between June 1 and September 5, 2022, were obtained from the "Hospital-based surveillance of COVID-19 in Switzerland"-database and classified as healthcare- or community-associated based on time of disease onset. Institutions provided information regarding institutional masking policies for healthcare workers and other prevention policies. The percentage of healthcare-associated SARS-CoV-2 infections was calculated per institution and per type of mask policy. The association of healthcare-associated SARS-CoV-2 infections with mask policies was tested using a negative binominal mixed-effect model.

RESULTS

We included 2'980 SARS-CoV-2 infections from 13 institutions, 444 (15%) were classified as healthcare-associated. Between June 20 and June 30, 2022, six (46%) institutions switched to a more stringent mask policy. The percentage of healthcare-associated infections subsequently declined in institutions with policy switch but not in the others. In particular, the switch from situative masking (standard precautions) to general masking of HCW in contact with patients was followed by a strong reduction of healthcare-associated infections (rate ratio 0.39, 95% CI 0.30-0.49). In contrast, when compared across hospitals, the percentage of health-care associated infections was not related to mask policies.

CONCLUSIONS

Our findings suggest switching to a more stringent mask policy may be beneficial during increases of healthcare-associated SARS-CoV-2 infections at an institutional level.

Effectiveness of wearing masks during the COVID-19 outbreak in cohort and case-control studies: a systematic review and meta-analysis

OBJECTIVE

To evaluate the efficacy of wearing a mask to prevent COVID-19 infection.

METHODS

This was a systematic review and meta-analysis of cohort and case-control studies, considering the best level of evidence available. Electronic databases (MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Clinical Trials.gov) were searched to identify studies that evaluated the effectiveness of wearing masks compared with that of not wearing them during the COVID-19 pandemic. Risk of bias and quality of evidence were assessed using the Cochrane risk of bias tool and the Grading of Recommendations Assessment, Development, and Evaluation.

RESULTS

Of the 1,028 studies identified, 9 met the inclusion criteria (2 cohort studies and 7 case-control studies) and were included in the analysis. The meta-analysis using cohort studies alone showed statistically significant differences, wearing a cloth mask decreased by 21% [RD = -0.21 (95% CI, -0.34 to -0.07); I2 = 0%; p = 0,002] the risk of COVID-19 infection, but the quality of evidence was low. Regarding case-control studies, wearing a surgical mask reduced the chance of COVID-19 infection [OR = 0.51 (95% CI, 0.37-0.70); I2 = 47%; p = 0.0001], as did wearing an N95 respirator mask [OR = 0.31 (95% CI, 0.20-0.49); I2 = 0%; p = 0.00001], both with low quality of evidence.

CONCLUSIONS

In this systematic review with meta-analysis, we showed the effectiveness of wearing masks in the prevention of SARS-CoV-2 infection regardless of the type of mask (disposable surgical mask, common masks, including cloth masks, or N95 respirators), although the studies evaluated presented with low quality of evidence and important biases.

Association between face mask use and risk of SARS-CoV-2 infection: Cross-sectional study

We examined the association between face masks and risk of infection with SARS-CoV-2 using cross-sectional data from 3,209 participants in a randomized trial exploring the effectiveness of glasses in reducing the risk of SARS-CoV-2 infection. Face mask use was based on participants' response to the end-of-follow-up survey. We found that the incidence of self-reported COVID-19 was 33% (aRR 1.33; 95% CI 1.03-1.72) higher in those wearing face masks often or sometimes, and 40% (aRR 1.40; 95% CI 1.08-1.82) higher in those wearing face masks almost always or always, compared to participants who reported wearing face masks never or almost never. We believe the observed increase in the incidence of infection associated with wearing a face mask is likely due to unobservable and hence nonadjustable differences between those wearing and not wearing a mask. Observational studies reporting on the relationship between face mask use and risk of respiratory infections should be interpreted cautiously, and more randomized trials are needed.

How have mathematical models contributed to understanding the transmission and control of SARS-CoV-2 in healthcare settings? A systematic search and review

Since the onset of the COVID-19 pandemic, mathematical models have been widely used to inform public health recommendations regarding COVID-19 control in healthcare settings. The objective of this study was to systematically review SARS-CoV-2 transmission models in healthcare settings, and to summarize their contributions to understanding nosocomial COVID-19. A systematic search and review of published articles indexed in PubMed was carried out. Modelling studies describing dynamic inter-individual transmission of SARS-CoV-2 in healthcare settings, published by mid-February 2022 were included. Models have mostly focused on acute-care and long-term-care facilities in high-income countries. Models have quantified outbreak risk, showing great variation across settings and pandemic periods. Regarding surveillance, routine testing rather than symptom-based was highlighted as essential for COVID-19 prevention due to high rates of silent transmission. Surveillance impacts depended critically on testing frequency, diagnostic sensitivity, and turn-around time. Healthcare re-organization also proved to have large epidemiological impacts: beyond obvious benefits of isolating cases and limiting inter-individual contact, more complex strategies (staggered staff scheduling, immune-based cohorting) reduced infection risk. Finally, vaccination impact, while highly effective for limiting COVID-19 burden, varied substantially depending on assumed mechanistic impacts on infection acquisition, symptom onset and transmission. Modelling results form an extensive evidence base that may inform control strategies for future waves of SARS-CoV-2 and other viral respiratory pathogens. We propose new avenues for future models of healthcare-associated outbreaks, with the aim of enhancing their efficiency and contributions to decision-making.

How to update a living systematic review and keep it alive during a pandemic: a practical guide

BACKGROUND

The covid-19 pandemic has highlighted the role of living systematic reviews. The speed of evidence generated during the covid-19 pandemic accentuated the challenges of managing high volumes of research literature.

METHODS

In this article, we summarise the characteristics of ongoing living systematic reviews on covid-19, and we follow a life cycle approach to describe key steps in a living systematic review.

RESULTS

We identified 97 living systematic reviews on covid-19, published up to 7th November 2022, which focused mostly on the effects of pharmacological interventions (n = 46, 47%) or the prevalence of associated conditions or risk factors (n = 30, 31%). The scopes of several reviews overlapped considerably. Most living systematic reviews included both observational and randomised study designs (n = 45, 46%). Only one-third of the reviews has been updated at least once (n = 34, 35%). We address practical aspects of living systematic reviews including how to judge whether to start a living systematic review, methods for study identification and selection, data extraction and evaluation, and give recommendations at each step, drawing from our own experience. We also discuss when it is time to stop and how to publish updates.

CONCLUSIONS

Methods to improve the efficiency of searching, study selection, and data extraction using machine learning technologies are being developed, their performance and applicability, particularly for reviews based on observational study designs should improve, and ways of publishing living systematic reviews and their updates will continue to evolve. Finally, knowing when to end a living systematic review is as important as knowing when to start.

Revisiting the personal protective equipment components of transmission-based precautions for the prevention of COVID-19 and other respiratory virus infections in healthcare

The COVID-19 pandemic highlighted some potential limitations of transmission-based precautions. The distinction between transmission through large droplets vs aerosols, which have been fundamental concepts guiding infection control measures, has been questioned, leading to considerable variation in expert recommendations on transmission-based precautions for COVID-19. Furthermore, the application of elements of contact precautions, such as the use of gloves and gowns, is based on low-quality and inconclusive evidence and may have unintended consequences, such as increased incidence of healthcare-associated infections and spread of multidrug-resistant organisms. These observations indicate a need for high-quality studies to address the knowledge gaps and a need to revisit the theoretical background regarding various modes of transmission and the definitions of terms related to transmission. Further, we should examine the implications these definitions have on the following components of transmission-based precautions: (i) respiratory protection, (ii) use of gloves and gowns for the prevention of respiratory virus infections, (iii) aerosol-generating procedures and (iv) universal masking in healthcare settings as a control measure especially during seasonal epidemics. Such a review would ensure that transmission-based precautions are consistent and rationally based on available evidence, which would facilitate decision-making, guidance development and training, as well as their application in practice.

Major Update: Masks for Prevention of SARS-CoV-2 in Health Care and Community Settings-Final Update of a Living, Rapid Review

BACKGROUND

Optimal use of masks for preventing COVID-19 is unclear.

PURPOSE

To update an evidence synthesis on N95, surgical, and cloth mask effectiveness in community and health care settings for preventing SARS-CoV-2 infection.

DATA SOURCES

MEDLINE, EMBASE, medRxiv (3 June 2022 to 2 January 2023), and reference lists.

STUDY SELECTION

Randomized trials of interventions to increase mask use and risk for SARS-CoV-2 infection and observational studies of mask use that controlled for potential confounders.

DATA EXTRACTION

Two investigators sequentially abstracted study data and rated quality.

DATA SYNTHESIS

Three randomized trials and 21 observational studies were included. In community settings, mask use may be associated with a small reduced risk for SARS-CoV-2 infection versus no mask use, on the basis of 2 randomized trials and 7 observational studies. In routine patient care settings, surgical masks and N95 respirators may be associated with similar risk for SARS-CoV-2 infection, on the basis of 1 new randomized trial with some imprecision and 4 observational studies. Evidence from observational studies was insufficient to evaluate other mask comparisons due to methodological limitations and inconsistency.

LIMITATION

Few randomized trials, studies had methodological limitations and some imprecision, suboptimal adherence and pragmatic aspects of randomized trials potentially attenuated benefits, very limited evidence on harms, uncertain applicability to Omicron variant predominant era, meta-analysis not done due to heterogeneity, unable to formally assess for publication bias, and restricted to English-language articles.

CONCLUSION

Updated evidence suggests that masks may be associated with a small reduction in risk for SARS-CoV-2 infection in community settings. Surgical masks and N95 respirators may be associated with similar infection risk in routine patient care settings, but a beneficial effect of N95 respirators cannot be ruled out.

PRIMARY FUNDING SOURCE

None.

Insights for COVID-19 in 2023

Predictions for a near end of the pandemic by the World Health Organization should be interpreted with caution. Current evidence indicates that the efficacy of a fourth dose of classical mRNA vaccines (BT162b2 or mRNA-1273) is low and short-lived in preventing SARS-CoV-2 infection in its predominant variant (Omicron). However, its efficacy is high against severe symptomatic infection, hospitalization and death. The new vaccines being introduced are bivalent and active against the Omicron variants. Potential new vaccines to be introduced in the coming year include a vaccine based on a recombinant protein that emulates the receptor binding domain of the Spike protein under development by the Spanish company Hipra, as well as vaccines for nasal or oral administration. Available information suggests that vaccines against COVID-19 can be administered in association with influenza vaccination without particular complications. New drugs against COVID-19, both antiviral and anti-inflammatory, are under investigation, but this does not seem to be the case with monoclonal antibodies. The indication to use masks in some circumstances will be maintained next year in view of the accumulation of scientific data on their efficacy. Finally, the long COVID or Post-COVID syndrome may continue to affect a very high proportion of patients who have had the disease, requiring combined diagnostic and therapeutic resources.

Evaluation of the bacterial contamination of face masks worn by personnel in a center of COVID 19 hospitalized patients: A cross-sectional study

Background

During the Coronavirus Pandemic, the use of masks has increased significantly. The lack of control on hygiene protocols and the need to use PPE properly increases the spread of bacterial infection. The purpose of this study was to investigate the degree of contamination and frequency of bacterial species isolated from surgical and N95 masks used by hospital personnel.

Methods

A total number of 175 masks were collected from staff working in Sina hospital (Hamadan province, Iran) during the first six months of 2022. The bacterial contamination of masks were evaluated and identified using biochemical kits. Antimicrobial susceptibility testing of the isolates were done using Kirby-Bauer methods and MIC were assessed for each isolate against different disinfectants (Sodium hypochlorite 5%, Hydrogen Peroxide 3%, Ethanol 70% and Deconex).

Results

Of 175 masks, 471 bacterial isolates were detected including 9 species. The most prevalent strain were Coagulase negative Staphylococcus (28%) followed by Acinetobacter (20.8%) and Pseudomonas (13.8%), while, Klebsiealla and Enterococcus were the least frequent species with the rate of 3.8% and 1.2%, respectively. The results of MIC methods indicated that all 471 strains were resistant to ehtanol70% and sensitive to hydrogen peroxide 3%. Furthermore, the mean average of Deconex inhibitory effect is lower than Sodium hypochlorite 5%.

Conclusions

According to the results of this study, there was a high prevalence of CoNS, Acinetobacter and Pseudomonas in hospital with a high resistance pattern against antibiotics especially Ampicillin and disinfectants.

Non-pharmaceutical interventions and risk of COVID-19 infection: survey of U.K. public from November 2020 - May 2021

INTRODUCTION

Non-pharmaceutical interventions (NPIs), such as handwashing, social distancing and face mask wearing, have been widely promoted to reduce the spread of COVID-19. This study aimed to explore the relationship between self-reported use of NPIs and COVID-19 infection.

METHODS

We conducted an online questionnaire study recruiting members of the UK public from November 2020 to May 2021. The association between self-reported COVID-19 illness and reported use of NPIs was explored using logistic regression and controlling for participant characteristics, month of questionnaire completion, and vaccine status. Participants who had been exposed to COVID-19 in their household in the previous 2 weeks were excluded.

RESULTS

Twenty-seven thousand seven hundred fifty-eight participants were included and 2,814 (10.1%) reported having a COVID-19 infection. The odds of COVID-19 infection were reduced with use of a face covering in unadjusted (OR 0.17 (95% CI: 0.15 to 0.20) and adjusted (aOR 0.19, 95% CI 0.16 to 0.23) analyses. Social distancing (OR 0.27, 95% CI: 0.22 to 0.31; aOR 0.35, 95% CI 0.28 to 0.43) and handwashing when arriving home (OR 0.57, 95% CI 0.46 to 0.73; aOR 0.63, 95% CI: 0.48 to 0.83) also reduced the odds of COVID-19. Being in crowded places of 10-100 people (OR 1.89, 95% CI: 1.70 to 2.11; aOR 1.62, 95% CI: 1.42 to 1.85) and > 100 people (OR 2.33, 95% CI: 2.11 to 2.58; aOR 1.73, 95% CI: 1.53 to 1.97) were both associated with increased odds of COVID-19 infection. Handwashing before eating, avoiding touching the face, and cleaning things with virus on were all associated with increased odds of COVID-19 infections.

CONCLUSIONS

This large observational study found evidence for strong protective effects for individuals from use of face coverings, social distancing (including avoiding crowded places) and handwashing on arriving home on developing COVID-19 infection. We also found evidence for an increased risk associated with other behaviours, possibly from recall bias.

A Trendline and Predictive Analysis of the First-Wave COVID-19 Infections in Malta

Following the first COVID-19 infected cases, Malta rapidly imposed strict lockdown measures, including restrictions on international travel, together with national social distancing measures, such as prohibition of public gatherings and closure of workplaces. The study aimed to elucidate the effect of the intervention and relaxation of the social distancing measures upon the infection rate by means of a trendline analysis of the daily case data. In addition, the study derived a predictive model by fitting historical data of the SARS-CoV-2 positive cases within a two-parameter Weibull distribution, whilst incorporating swab-testing rates, to forecast the infection rate at minute computational expense. The trendline analysis portrayed the wave of infection to fit within a tri-phasic pattern, where the primary phase was imposed with social measure interventions. Following the relaxation of public measures, the two latter phases transpired, where the two peaks resolved without further escalation of national measures. The derived forecasting model attained accurate predictions of the daily infected cases, attaining a high goodness-of-fit, utilising uncensored government-official infection-rate and swabbing-rate data within the first COVID-19 wave in Malta.

Self-Perceived Halitosis and Related Factors Among the Mask-Wearing Population During the COVID-19 Pandemic in Delhi, India: A Cross-Sectional Study

Introduction Halitosis (oral malodor) is a common health condition throughout the world. In India, data on self-reported halitosis and related factors is limited. Mouth mask usage has been made compulsory after the coronavirus disease 2019 (COVID-19) pandemic. This could possibly alter oral microflora and environment and contribute to halitosis. The aim of the study was to determine the prevalence of self-perceived halitosis (SPH) among mask-wearing patients visiting a tertiary care dental hospital in Delhi, India. Methods A cross‑sectional study was conducted among a convenience sample of 300 patients visiting a tertiary care dental hospital in the capital of India. SPH status was measured using a self-designed and structured questionnaire containing socio-demographic factors, mask-related habits, and self-perceived oral health status. Statistical analysis was done using Jamovi software (The jamovi project, Sydney, Australia) version 1.8. Descriptive analysis followed by a chi-square test and a multivariate logistic regression test was applied. Results Bad breath was perceived by 86 study subjects. Of the participants, 16.7% felt that they had bad breath before the pandemic, and 38% of the participants had an increased perception or feeling of bad breath since regular mask usage. Of the participants, 42.7% felt that they had an increased feeling of dryness in the mouth post-pandemic. SPH status was associated with mask usage frequency (p<0.001), change (p<0.001) and type of mask (p=0.004), increased feeling of dryness (p<0.001), frequency of toothbrushing (p<0.001), self-reported oral disease (p=0.007), and dental treatment in the past 12 months (p=0.005). Conclusion The SPH status of the study population was associated with mask-related habits and self-reported oral health status. The findings highlight the importance of possible amendments in preventive and curative care for patients with halitosis post-COVID-19 pandemic.

Comparative Effectiveness of Mask Type in Preventing SARS-CoV-2 in Health Care Workers: Uncertainty Persists

Two and a half years after the emergence of the COVID-19 pandemic, Loeb and colleagues reported the first randomized trial of N95 respirators versus medical masks in health care workers. The editorialist discusses the findings and highlights remaining areas of uncertainty about optimal mask type.

Effect of FFP2/N95 facemask wear on retinal and choroidal thickness profile in healthy subjects

AIM

To investigate the influence of non-oil 95 (N95)/filtering facepiece 2 (FFP2) facemask wear on retinal thickness, choroidal thickness (CT), retinal nerve fiber layer thickness (RNFLT), and ganglion cell layer thickness (GCLT) in healthy subjects.

METHODS

In this prospective study, 53 healthy participants who used FFP2/N95 facemask were enrolled. Participants underwent optical coherence tomography imaging before and at 1 and 4h following FFP2/N95 facemask wear. The last imaging session was performed 1h after FFP2/N95 removal. Retinal thickness, CT, RNFLT, and GCLT were assessed at each session. Vital parameters were also assessed.

RESULTS

The pulse rate of the subjects significantly decreased at 1 and 4h compared to baseline values (P<0.05). No significant changes in retinal thickness, RNFLT, and GCLT were observed in the study. CT profile showed a significant increase at all measured locations except 1-mm temporal, 1-mm inferior and 2-mm inferior points following FFP2/N95 wear which turned to baseline values after FFP2/N95 removal. Pulse rate and CT changes at 4h were significantly correlated (P<0.05).

CONCLUSION

Parasympathetic activation during FFP2/N95 facemask wear might have a role on elevated CT measurements in healthy individuals by virtue of increased choroidal blood flow.

Evidence in decision-making in the context of COVID-19 in Latin America

Background

The pace of the COVID-19 pandemic poses an unprecedented challenge to the evidence-to-decision process. Latin American countries have responded to COVID-19 by introducing interventions to both mitigate the risk of infection and to treat cases. Understanding how evidence is used to inform government-level decision-making at a national scale is crucial for informing country and regional actors in ongoing response efforts.

Objectives

This study was undertaken between February-May 2021 and aims to characterise the best available evidence (BAE) and assess the extent to which it was used to inform decision-making in 21 Latin American countries, in relation to pharmaceutical (PI) and non-pharmaceutical interventions (NPI) related to COVID-19, including the use of therapeutics (corticosteroids, hydroxychloroquine/chloroquine and ivermectin), facemask use in the community setting and the use of diagnostic tests as a requirement for international travel.

Method

A three-phase methodology was used to; (i) characterise the BAE for each intervention using an umbrella review, (ii) identify government-level decisions for each intervention through a document review and (iii) assess the use of evidence to inform decisions using a novel adapted framework analysis.

Findings

The BAE is characterized by 17 living and non-living systematic reviews as evolving, and particularly uncertain for NPIs. 107 country-level documents show variation in both content and timing of decision outcomes across intervention types, with the majority of decisions taken at a time of evidence uncertainty, with only 5 documents including BAE. Seven out of eight key indicators of an evidence-to-decision process were identified more frequently among PIs than either NPI of facemask use or testing prior to travel. Overall evidence use was reported more frequently among PIs than either NPI of facemask use or travel testing (92%, 28% and 29%, respectively).

Interpretation

There are limitations in the extent to which evidence use in decision-making is reported across the Latin America region. Institutionalising this process and grounding it in existing and emerging methodologies can facilitate the rapid response in an emergency setting.

Funding

No funding was sourced for this work.

Using the concept of circular economy to reduce the environmental impact of COVID-19 face mask waste

COVID-19 pandemic has posed severe threats to the society globally. World Health Organization (WHO) guidelines suggest that people wear face masks as a precautionary measure daily. This has resulted in the generation of massive amounts of mask-associated waste in the environment. Owing to the criticality of the epidemic, there has not been a large-scale investigation on where to discard masks, making this situation daunting. As the pandemic continues, the use of masks continues to increase; repeated use and disposal of masks has become an imperative issue. Most disposable masks comprise chemical fibers in the filter layer. Without proper treatment and disposal, these large amounts of chemical waste will eventually flow into rivers or oceans, leading to serious pollution. Therefore, to reduce the negative effects on the marine environment, it is crucial that we produce reusable masks and reduce disposable wearing habits. This study aimed to resolve this challenge using textile materials created by recycling fish-scale waste. Functional and comfortable masks manufactured without chemical additives to achieve multiple functions can increase the willingness to wear and be reused. Hence, product use can be prolonged, and the use of disposable masks can be curtailed. The product manufactured herein is biodegradable in nature, thus conforming to the green sustainable initiative.

Effectiveness and adherence to closed face shields in the prevention of COVID-19 transmission: a non-inferiority randomized controlled trial in a middle-income setting (COVPROSHIELD)

Background

The use of respiratory devices can mitigate the spread of diseases such as COVID-19 in community settings. We aimed to determine the effectiveness of closed face shields with surgical face masks to prevent SARS-CoV-2 transmission in working adults during the COVID-19 pandemic in Bogotá, Colombia.

Methods

An open-label non-inferiority randomized controlled trial that randomly assigned participants to one of two groups: the intervention group was instructed to wear closed face shields with surgical face masks, and the active control group was instructed to wear only surgical face masks. The primary outcome was a positive reverse transcription polymerase chain reaction test, IgG/IgM antibody test for SARS-CoV-2 detection, or both during and at the end of the follow-up period of 21 days. The non-inferiority limit was established at − 5%.

Results

A total of 316 participants were randomized, 160 participants were assigned to the intervention group and 156 to the active control group. In total, 141 (88.1%) participants in the intervention group and 142 (91.0%) in the active control group completed the follow-up. Primary outcome: a positive SARS-CoV-2 test result was identified in one (0.71%) participant in the intervention group and three (2.1%) in the active control group. In the intention-to-treat analysis, the absolute risk difference was − 1.40% (95% CI [− 4.14%, 1.33%]), and in the per-protocol analysis, the risk difference was − 1.40% (95% CI [− 4.20, 1.40]), indicating non-inferiority of the closed face shield plus face mask (did not cross the non-inferiority limit).

Conclusions

The use of closed face shields and surgical face masks was non-inferior to the surgical face mask alone in the prevention of SARS-CoV-2 infection in highly exposed groups. Settings with highly active viral transmission and conditions such as poor ventilation, crowding, and high mobility due to occupation may benefit from the combined use of masks and closed face shields to mitigate SARS-CoV-2 transmission.

Trial registration

ClinicalTrials.gov NCT04647305. Registered on November 30, 2020

Antiviral Effects of Heparan Sulfate Analogue‐Modified Two‐Dimensional MXene Nanocomposites on PRRSV and SARS‐CoV‐2

Due to the worldwide impact of viruses such as SARS‐CoV‐2, researchers have paid extensive attention to antiviral reagents against viruses. Despite extensive research on two‐dimensional (2D) transition metal carbides (MXenes) in the field of biomaterials, their antiviral effects have received little attention. In this work, heparan sulfate analogue (sodium 3‐mercapto‐1‐propanesulfonate, MPS) modified 2D MXene nanocomposites (Ti₃C₂‐Au‐MPS) for prevention of viral infection are prepared and investigated using severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) pseudovirus and porcine reproductive and respiratory syndrome virus (PRRSV) as two model viruses. Ti₃C₂‐Au‐MPS nanocomposites are shown to possess antiviral properties in the different stages of PRRSV proliferation, such as direct interaction with PRRS virions and inhibiting their adsorption and penetration in the host cell. Additionally, Ti₃C₂‐Au‐MPS nanocomposites can strongly inhibit the infection of SARS‐CoV‐2 pseudovirus as shown by the contents of its reporter gene GFP and luciferase. These results demonstrate the potential broad‐spectrum antiviral property of Ti₃C₂‐Au‐MPS nanocomposites against viruses with the receptor of heparin sulfate. This work sheds light on the specific antiviral effects of MXene‐based nanocomposites against viruses and may facilitate further exploration of their antiviral applications.

Diurnal changes of noninvasive parameters of ocular surface in healthy subjects before and after continuous face mask wearing during the COVID-19 pandemic

To investigate whether diurnal changes in noninvasive ocular surface parameters and subjective symptoms occur in healthy subjects wearing face mask who were analyzed before and after 8 h of continuous use. In this prospective cross-sectional study, healthy volunteers attending the same workplace environment underwent a noninvasive ocular surface workup by means of Keratograph 5 M (Oculus, Wetzlar, Germany) in the same day at 2 different time points: (i) in the early morning before wearing face mask (T0); (ii) after 8 h of continuous face mask use (T1). Noninvasive break-up time (NIBUT), tear meniscus height (TMH), ocular redness and meibomian gland dropout were measured. All subjects were asked to complete the Ocular Surface Disease Index (OSDI) questionnaire before and after 8 h of face mask wearing. Data from 20 healthy subjects (10 males and 10 females, mean age 25.1 ± 3.9 years) were included. Mean value of TMH decreased significantly from 0.29 ± 0.07 at T0 to 0.23 ± 0.07 mm at T1 (P < 0.001); conversely, mean values of NIBUT, redness score and meibomian gland dropout did not change significantly after continuous face mask wearing (always P > 0.532). Concerning ocular discomfort symptoms, mean value of OSDI score worsened significantly at T1 compared to T0 (from 12.9 ± 12.6 to 19.4 ± 12.0; P = 0.017). Continuous face mask wearing for 8 h led to decreased TMH associated with the onset of ocular discomfort symptoms in young healthy subjects.

Accuracy and Efficiency of Machine Learning-Assisted Risk-of-Bias Assessments in "Real-World" Systematic Reviews : A Noninferiority Randomized Controlled Trial

BACKGROUND

Automation is a proposed solution for the increasing difficulty of maintaining up-to-date, high-quality health evidence. Evidence assessing the effectiveness of semiautomated data synthesis, such as risk-of-bias (RoB) assessments, is lacking.

OBJECTIVE

To determine whether RobotReviewer-assisted RoB assessments are noninferior in accuracy and efficiency to assessments conducted with human effort only.

DESIGN

Two-group, parallel, noninferiority, randomized trial. (Monash Research Office Project 11256).

SETTING

Health-focused systematic reviews using Covidence.

PARTICIPANTS

Systematic reviewers, who had not previously used RobotReviewer, completing Cochrane RoB assessments between February 2018 and May 2020.

INTERVENTION

In the intervention group, reviewers received an RoB form prepopulated by RobotReviewer; in the comparison group, reviewers received a blank form. Studies were assigned in a 1:1 ratio via simple randomization to receive RobotReviewer assistance for either Reviewer 1 or Reviewer 2. Participants were blinded to study allocation before starting work on each RoB form.

MEASUREMENTS

Co-primary outcomes were the accuracy of individual reviewer RoB assessments and the person-time required to complete individual assessments. Domain-level RoB accuracy was a secondary outcome.

RESULTS

Of the 15 recruited review teams, 7 completed the trial (145 included studies). Integration of RobotReviewer resulted in noninferior overall RoB assessment accuracy (risk difference, -0.014 [95% CI, -0.093 to 0.065]; intervention group: 88.8% accurate assessments; control group: 90.2% accurate assessments). Data were inconclusive for the person-time outcome (RobotReviewer saved 1.40 minutes [CI, -5.20 to 2.41 minutes]).

LIMITATION

Variability in user behavior and a limited number of assessable reviews led to an imprecise estimate of the time outcome.

CONCLUSION

In health-related systematic reviews, RoB assessments conducted with RobotReviewer assistance are noninferior in accuracy to those conducted without RobotReviewer assistance.

PRIMARY FUNDING SOURCE

University College London and Monash University.

Prevalence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Antibodies in the Mozambican Population: A Cross-Sectional Serologic Study in 3 Cities, July-August 2020

BACKGROUND

The extent of population exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was uncertain in many African countries during the onset of the pandemic.

METHODS

We conducted a cross-sectional study and randomly selected and surveyed general population and occupational groups from 6 July to 24 August 2020, in 3 cities in Mozambique. Anti-SARS-CoV-2-specific immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies were measured using a point-of-care rapid test. The prevalence was weighted for population (by age, sex, and city) and adjusted for test sensitivity and specificity.

RESULTS

A total of 21 183 participants, including 11 143 from the general population and 10 040 from occupational groups, were included across all 3 cities. General population seropositivity (IgM or IgG) prevalence was 3.0% (95% confidence interval [CI], 1.0%-6.6%) in Pemba, 2.1% (95% CI, 1.2%-3.3%) in Maputo City, and 0.9% (95% CI, .1%-1.9%) in Quelimane. The prevalence in occupational groups ranged from 2.8% (95% CI, 1.3%-5.2%) to 5.9% (95% CI, 4.3%-8.0%) in Pemba, 0.3% (95% CI, .0%-2.2%) to 4.0% (95% CI, 2.6%-5.7%) in Maputo City, and 0.0% (95% CI, .0%-.7%) to 6.6% (95% CI, 3.8%-10.5%) in Quelimane, and showed variations between the groups tested.

CONCLUSIONS

In the first representative COVID-19 serosurveys in Mozambique, in mid-2020, weighted and assay-adjusted seroprevalence in 3 provincial capitals of anti-SARS-CoV-2 ranged from 0.9% to 3.0%, whereas adjusted prevalence in occupational groups ranged from 0.0% to 6.6% with variation between groups. Exposure to SARS-CoV-2 was extensive during the first pandemic wave, and transmission may have been more intense among occupational groups. These data have been of utmost importance to inform public health intervention to control and respond to the pandemic in Mozambique.

P2/N95 respirators & surgical masks to prevent SARS-CoV-2 infection: Effectiveness & adverse effects

BACKGROUND

Millions of people have acquired and died from SARS-CoV-2 infection during the COVID-19 pandemic. Healthcare workers (HCWs) are required to wear personal protective equipment (PPE), including surgical masks and P2/N95 respirators, to prevent infection while treating patients. However, the comparative effectiveness of respirators and masks in preventing SARS-CoV-2 infection and the likelihood of experiencing adverse events (AEs) with wear are unclear.

METHODS

Searches were carried out in PubMed, Europe PMC and the Cochrane COVID-19 Study Register to 14 June 2021. A systematic review of comparative epidemiological studies examining SARS-CoV-2 infection or AE incidence in HCWs wearing P2/N95 (or equivalent) respirators and surgical masks was performed. Article screening, risk of bias assessment and data extraction were duplicated. Meta-analysis of extracted data was carried out in RevMan.

RESULTS

Twenty-one studies were included, with most having high risk of bias. There was no statistically significant difference in respirator or surgical mask effectiveness in preventing SARS-CoV-2 infection (OR 0.85, [95%CI 0.72, 1.01]). Healthcare workers experienced significantly more headaches (OR 2.62, [95%CI 1.18, 5.81]), respiratory distress (OR 4.21, [95%CI 1.46, 12.13]), facial irritation (OR 1.80, [95%CI 1.03, 3.14]) and pressure-related injuries (OR 4.39, [95%CI 2.37, 8.15]) when wearing respirators compared to surgical masks.

CONCLUSION

The existing epidemiological evidence does not enable definitive assessment of the effectiveness of respirators compared to surgical masks in preventing infection. Healthcare workers wearing respirators may be more likely to experience AEs. Effective mitigation strategies are important to ensure the uptake and correct use of respirators by HCWs.

Nonpharmaceutical interventions to prevent viral respiratory infection in community settings: an umbrella review

Background

Respiratory viruses pose an important public health threat to most communities. Nonpharmaceutical interventions (NPIs) such as masks, hand hygiene or physical distancing, among others, are believed to play an important role in reducing transmission of respiratory viruses. In this umbrella review, we summarise the evidence of the effectiveness of NPIs for the prevention of respiratory virus transmission in the community setting.

Observations

A systematic search of PubMed, Embase, Medline and Cochrane reviews resulted in a total of 24 studies consisting of 11 systematic reviews and meta-analyses, 12 systematic reviews without meta-analyses and one standalone meta-analysis. The current evidence from these data suggests that hand hygiene is protective against respiratory viral infection. The use of hand hygiene and facemasks, facemasks alone and physical distancing were interventions with inconsistent evidence. Interventions such as school closures, oral hygiene or nasal saline rinses were shown to be effective in reducing the risk of influenza; however, the evidence is sparse and mostly of low and critically low quality.

Conclusions

Studies on the effectiveness of NPIs for the prevention of respiratory viral transmission in the community vary in study design, quality and reported effectiveness. Evidence for the use of hand hygiene or facemasks is the strongest; therefore, the most reasonable suggestion is to use hand hygiene and facemasks in the community setting.

Effects of wearing surgical masks on fraction of inspired oxygen in spontaneously breathing patients: improving safety for frontline healthcare professionals under pandemic situations

BACKGROUND

During pandemic situations, many guidelines recommend that surgical masks be worn by both healthcare professionals and infected patients in healthcare settings. The purpose of this study was to clarify the levels and changes of oxygen concentration over time while oxygen was administered over a surgical mask.

METHODS

Patients scheduled to undergo general anesthesia (n = 99) were enrolled in this study. First, patients were administered oxygen at 6 L/min via an oxygen mask over a surgical mask for 5 min. The patients removed the surgical mask and then took a 3-min break; thereafter, the same amount of oxygen was administered for another 5 min via the oxygen mask. We measured the fraction of inspired oxygen (FiO₂), the end-tidal CO₂ (EtCO₂), and respiratory frequency every minute for 5 min, both while administering oxygen with and without a surgical mask. The FiO₂ was measured at the beginning of inspiration and the EtCO₂ was measured at the end of expiration.

RESULTS

The FiO₂ at 5 min was significantly lower when breathing with a surgical mask than that without it (mean difference: 0.08 [95% CI: 0.067-0.10]; p <  0.001). In contrast, the EtCO₂ at 5 min was significantly higher when breathing with a surgical mask than that without it (mean difference: 11.9 mmHg [95% CI: 10.9-12.9]; p <  0.001).

CONCLUSION

The FiO₂ was lower when oxygen was administered over surgical masks than when patients did not wear surgical masks. Oxygen flow may need to be adjusted in moderately ill patients requiring oxygen administration.

COVID-19 in people with rheumatic diseases: risks, outcomes, treatment considerations

The COVID-19 pandemic has brought challenges for people with rheumatic disease in addition to those faced by the general population, including concerns about higher risks of infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and poor outcomes of COVID-19. The data that are now available suggest that rheumatic disease is associated with a small additional risk of SARS-CoV-2 infection, and that outcomes of COVID-19 are primarily influenced by comorbidities and particular disease states or treatments. Despite considerable advances in our knowledge of which therapeutic agents provide benefits in COVID-19, and of what constitutes effective vaccination strategies, the specific considerations that apply to people with rheumatic disease are yet to be definitively addressed. An overview of the most important COVID-19 studies to date that relate to people with rheumatic disease can contribute to our understanding of the clinical-care requirements of this population.

Modeling COVID-19 Mortality Across 44 Countries: Face Covering May Reduce Deaths

INTRODUCTION

Despite ongoing efforts to vaccinate communities against COVID-19, the necessity of face mask use in controlling the pandemic remains subject to debate. Several studies have investigated face masks and COVID-19, covering smaller and less diverse populations than this study's sample. This study examines a hypothesized association of face-covering mandates with COVID-19 mortality decline across 44 countries in 2 continents.

METHODS

In a retrospective cohort study, changes in COVID-19‒related daily mortality rate per million population from February 15 to May 31, 2020 were compared between 27 countries with and 17 countries without face mask mandates in nearly 1 billion (911,446,220 total) people. Longitudinal mixed effect modeling was applied and adjusted for over 10 relevant demographic, social, clinical, and time-dependent confounders.

RESULTS

Average COVID-19 mortality per million was 288.54 in countries without face mask policies and 48.40 in countries with face mask policies. In no mask countries, adjusted average daily increase was 0.1553 - 0.0017 X (days since the first case) log deaths per million, compared with 0.0900 - 0.0009 X (days since the first case) log deaths per million in the countries with a mandate. A total of 60 days into the pandemic, countries without face mask mandates had an average daily increase of 0.0533 deaths per million, compared with the average daily increase of 0.0360 deaths per million for countries with face mask mandates.

CONCLUSIONS

This study's significant results show that face mask mandates were associated with lower COVID-19 deaths rates than the rates in countries without mandates. These findings support the use of face masks to prevent excess COVID-19 deaths and should be advised during airborne disease epidemics.

Surface Functionalization of Non-Woven Fabrics Using a Novel Silica-Resin Coating Technology: Antiviral Treatment of Non-Woven Fabric Filters in Surgical Masks

Masks are effective for preventing the spread of COVID-19 and other respiratory infections. If antimicrobial properties can be applied to the non-woven fabric filters in masks, they can become a more effective countermeasure against human-to-human and environmental infections. We investigated the possibilities of carrying antimicrobial agents on the fiber surfaces of non-woven fabric filters by applying silica-resin coating technology, which can form silica-resin layers on such fabrics at normal temperature and pressure. Scanning electron microscopy and electron probe microanalysis showed that a silica-resin layer was formed on the fiber surface of non-woven fabric filters. Bioassays for coronavirus and quantitative reverse transcription-polymerase chain reactions (RT-PCR) revealed that all antimicrobial agents tested loaded successfully onto non-woven fabric filters without losing their inactivation effects against the human coronavirus (inhibition efficacy: >99.999%). These results indicate that this technology could be used to load a functional substance onto a non-woven fabric filter by vitrifying its surface. Silica-resin coating technology also has the potential of becoming an important breakthrough not only in the prevention of infection but also in various fields, such as prevention of building aging, protection of various cultural properties, the realization of a plastic-free society, and prevention of environmental pollution.

Effectiveness of Mask-Wearing on Respiratory Illness Transmission in Community Settings: A Rapid Review

OBJECTIVE

Respiratory illnesses, including coronavirus disease 2019 (COVID-19), have resulted in millions of deaths globally. Guidance on mask-wearing in community settings has been inconsistent. This review examined the effectiveness of mask-wearing on respiratory virus transmission in community settings.

METHODS

A search was conducted for English language reports of randomized controlled trials of mask-wearing in the community and effect on laboratory-confirmed respiratory infections or influenza-like illness. Investigators abstracted study characteristics and assessed bias. Meta-analysis was conducted to calculate pooled risk estimates.

RESULTS

Eleven studies were included. In 7 studies that evaluated influenza-like illness symptoms as an outcome (3029 participants), this study found mask-wearing associated with a decreased risk of influenza-like illness (overall risk ratio [RR], 0.83; 95% confidence interval [CI], 0.71 to 0.96). Studies examining laboratory-confirmed respiratory infections as an outcome (10,531 participants) showed no statistically significant association between mask-wearing and infections (RR, 1.04; 95% CI, 0.60-1.80). However, masking combined with enhanced hand hygiene was associated with a decreased risk for both influenza-like illness symptoms (RR, 0.88; 95% CI, 0.51-1.51) and laboratory-confirmed respiratory infection (RR, 0.79; 95% CI, 0.52-1.18).

CONCLUSIONS

Masking in community settings decreases transmission of influenza-like illness. Mask-wearing combined with enhanced hand hygiene reduces transmission of influenza-like illness and laboratory-confirmed respiratory infection.

Transport Safety Concerning a Patient Infected With SARS-CoV-2 and Emergency Service Officers in an Ambulance Accident-A Case Study

The manifestation of a new pathogen, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), constitutes a new problem for modern health care systems. Developing updated standards for all emergency services working at an accident site during the pandemic has been a continuous challenge. The principal method of preventing the transmission of the SARS-CoV-2 virus is the use of personal protective equipment, such as protective suits, masks and goggles, or face shields. The study aims to present the recommended on-site procedures during the coronavirus pandemic based on the description of an accident of an ambulance transporting a patient with confirmed SARS-CoV-2 infection, emphasizing the actions taken by the emergency services sent to the accident site.

Advances in the Prophylaxis of Respiratory Infections by the Nasal and the Oromucosal Route: Relevance to the Fight with the SARS-CoV-2 Pandemic

In this time of COVID-19 pandemic, the strategies for prevention of the infection are a primary concern. Looking more globally on the subject and acknowledging the high degree of misuse of protective face masks from the population, we focused this review on alternative pharmaceutical developments eligible for self-defense against respiratory infections. In particular, the attention herein is directed to the nasal and oromucosal formulations intended to boost the local immunity, neutralize or mechanically “trap” the pathogens at the site of entry (nose or mouth). The current work presents a critical review of the contemporary methods of immune- and chemoprophylaxis and their suitability and applicability in topical mucosal dosage forms for SARS-CoV-2 prophylaxis.

Comparative effectiveness of N95, surgical or medical, and non-medical facemasks in protection against respiratory virus infection: A systematic review and network meta-analysis

The aim of this systematic review and network meta‐analysis is to evaluate the comparative effectiveness of N95, surgical/medical and non‐medical facemasks as personal protective equipment against respiratory virus infection. The study incorporated 35 published and unpublished randomized controlled trials and observational studies investigating specific mask effectiveness against influenza virus, SARS‐CoV, MERS‐CoV and SARS‐CoV‐2. We searched PubMed, Google Scholar and medRxiv databases for studies published up to 5 February 2021 (PROSPERO registration: CRD42020214729). The primary outcome of interest was the rate of respiratory viral infection. The quality of evidence was estimated using the GRADE approach. High compliance to mask‐wearing conferred a significantly better protection (odds ratio [OR], 0.43; 95% confidence interval [CI], 0.23–0.82) than low compliance. N95 or equivalent masks were the most effective in providing protection against coronavirus infections (OR, 0.30; CI, 0.20–0.44) consistently across subgroup analyses of causative viruses and clinical settings. Evidence supporting the use of medical or surgical masks against influenza or coronavirus infections (SARS, MERS and COVID‐19) was weak. Our study confirmed that the use of facemasks provides protection against respiratory viral infections in general; however, the effectiveness may vary according to the type of facemask used. Our findings encourage the use of N95 respirators or their equivalents (e.g., P2) for best personal protection in healthcare settings until more evidence on surgical and medical masks is accrued. This study highlights a substantial lack of evidence on the comparative effectiveness of mask types in community settings.

The evolution of the human healthcare system and implications for understanding our responses to COVID-19

The COVID-19 pandemic has revealed an urgent need for a comprehensive, multidisciplinary understanding of how healthcare systems respond successfully to infectious pathogens-and how they fail. This study contributes a novel perspective that focuses on the selective pressures that shape healthcare systems over evolutionary time. We use a comparative approach to trace the evolution of care-giving and disease control behaviours across species and then map their integration into the contemporary human healthcare system. Self-care and pro-health environmental modification are ubiquitous across animals, while derived behaviours like care for kin, for strangers, and group-level organizational responses have evolved via different selection pressures. We then apply this framework to our behavioural responses to COVID-19 and demonstrate that three types of conflicts are occurring: (1) conflicting selection pressures on individuals, (2) evolutionary mismatches between the context in which our healthcare behaviours evolved and our globalized world of today and (3) evolutionary displacements in which older forms of care are currently dispensed through more derived forms. We discuss the significance of understanding how healthcare systems evolve and change for thinking about the role of healthcare systems in society during and after the time of COVID-19-and for us as a species as we continue to face selection from infectious diseases.

Efficacy and practice of facemask use in general population: a systematic review and meta-analysis

In recent decades, respiratory infections, including SARS, HINI and the currently spreading COVID-19, caused by various viruses such as influenza and coronavirus have seriously threatened human health. It has generated inconsistent recommendations on the mandatory use of facemasks across countries on a population level due to insufficient evidence on the efficacy of facemask use among the general population. This meta-analysis aimed to explore (1) the efficacy of facemask use on preventing respiratory infections, and (2) the perceptions, intentions, and practice about facemask use among the general population worldwide. We searched PubMed, MEDLINE, Web of Science, Cochrane, bioRxiv, and medRxiv databases since inception to August 17, 2020. From 21,341 records identified, eight RCTs on facemask in preventing infections and 78 studies on perception, intention, and practice of facemask use among the general population were included in the analysis. The meta-analysis of RCTs found a significant protective effect of facemask intervention (OR = 0.84; 95% CI = 0.71-0.99; I2 = 0%). This protective effect was even more pronounced when the intervention duration was more than two weeks (OR = 0.76; 95% CI = 0.66-0.88; I2 = 0%). The meta-analysis of observational studies on perception, intention, and practice on facemask use showed that 71% of respondents perceived facemasks to be effective for infection prevention, 68% of respondents would wear facemasks, and 54% of respondents wore facemasks for preventing respiratory infections. Differences in perception, intention, and practice behavior of facemask use in different regions may be related to the impact of respiratory infections, regional culture, and policies. The governments and relevant organizations should make effort to reduce the barriers in the use of facemasks.

The Thought of Death in a Pandemic Era: Can Anxiety Determine the Nexus between the Accessibility, Availability and Use of Personal Protective Equipment (PPE) for COVID-19 and Work Behaviour among Aviation Workers?

Since the emergence of COVID-19, the aviation sector has been one of the numerous industries which have been affected the most. In this present paper, the thought of death among aviation workers as an indicator of anxiety at a time when the availability, access to, and use of Personal Protective Equipment (PPE) remains paramount to the survival of work in the line of duties and its influence on different work behaviors was assessed. The theoretical foundation of the study was built on the process efficiency theory, attentional interference theory, and the terror management theory (TMT), which focuses on both the psychological and emotional responses exhibited by people due to fear or worry about a specific situation. The study adopted an exploratory study design that incorporates a cross-sectional and self-reported survey among 646 frontline workers across 12 international airlines and the Ghana Airport Company Limited (GACL), Accra, Ghana using simple random sampling and convenient sampling techniques. After all the preliminary tests were performed, the path analysis estimated by Structural Equation Modelling (SEM) indicated that anxiety has a significant influence on workers’ stress-adaptive performance and task performance, but recorded no significant causal link with interpersonal performance. The findings indicated that all three proxies of employee work behaviours, which focus on both adaptive and task performance, were significantly related to workers’ access, availability, and use of PPE (APPE). The association between anxiety and APPE was also found to be significant. Bootstrapping mediation analysis shows that anxiety partially mediates the influence APPE has on both stress-adaptive performance and task performance, but did not show any mediating effect on the association between APPE and interpersonal performance. Among the three dimensions of death anxiety, both the fear of death (FDE) and death intrusion (DINT) indicated a significant partial mediating effect on the influence APPE has on all three multidimensional constructs of work behaviours. The findings literally prove that worrying about the fatality risk associated with COVID-19 is highly predictive.

A review on the transmission of COVID-19 based on cough/sneeze/breath flows

COVID-19 pandemic has recently had a dramatic impact on society. The understanding of the disease transmission is of high importance to limit its spread between humans. The spread of the virus in air strongly depends on the flow dynamics of the human airflows. It is, however, known that predicting the flow dynamics of the human airflows can be challenging due to different particles sizes and the turbulent aspect of the flow regime. It is thus recommended to present a deep analysis of different human airflows based on the existing experimental investigations. A validation of the existing numerical predictions of such flows would be of high interest to further develop the existing numerical model for different flow configurations. This paper presents a literature review of the experimental and numerical studies on human airflows, including sneezing, coughing and breathing. The dynamics of these airflows for different droplet sizes is discussed. The influence of other parameters, such as the viscosity and relative humidity, on the germs transmission is also presented. Finally, the efficacy of using a facemask in limiting the transmission of COVID-19 is investigated.

OUP accepted manuscript

Background

Healthcare workers (HCWs) are at risk from aerosol transmission of severe acute respiratory syndrome coronavirus 2. The aims of this study were to (1) quantify the protection provided by masks (surgical, fit-test_FAILED N95, fit-test_PASSED N95) and personal protective equipment (PPE), and (2) determine if a portable high-efficiency particulate air (HEPA) filter can enhance the benefit of PPE.

Methods

Virus aerosol exposure experiments using bacteriophage PhiX174 were performed. An HCW wearing PPE (mask, gloves, gown, face shield) was exposed to nebulized viruses (10⁸ copies/mL) for 40 minutes in a sealed clinical room. Virus exposure was quantified via skin swabs applied to the face, nostrils, forearms, neck, and forehead. Experiments were repeated with a HEPA filter (13.4 volume-filtrations/hour).

Results

Significant virus counts were detected on the face while the participants were wearing either surgical or N95 masks. Only the fit-test_PASSED N95 resulted in lower virus counts compared to control (P = .007). Nasal swabs demonstrated high virus exposure, which was not mitigated by the surgical/fit-test_FAILED N95 masks, although there was a trend for the fit-test_PASSED N95 mask to reduce virus counts (P = .058). HEPA filtration reduced virus to near-zero levels when combined with fit-test_PASSED N95 mask, gloves, gown, and face shield.

Conclusions

N95 masks that have passed a quantitative fit-test combined with HEPA filtration protects against high virus aerosol loads at close range and for prolonged periods of time.

Change in Pediatric Health Care Spending and Drug Utilization during the COVID-19 Pandemic

Objective: To evaluate how the restrictive measures implemented during the SARS-CoV-2 pandemic have influenced the incidence of the most common children’s diseases and the consumption of medications in 2020 compared to 2019. Methods: We involved all family pediatricians of the local health authority of Latina, from which we requested data of monthly visits in 2019 and 2020 for six common diseases disseminated through droplets and contact, and the territorial and integrative pharmaceutical unit of the area, from which we requested data of the net expenditure regarding the most commonly used drugs at pediatric age. Results: There was significant reduction in the incidence of the evaluated diseases and in the consumption of investigated drugs between 2019 and 2020 in the months when the restrictive measures were in place, with an attenuation of this effect during the months of the gradual loosening of those measures. Conclusion: Nonpharmaceutical intervention measures have caused changes in the diffusion of common pediatric diseases. We believe that the implementation of a reasonable containment strategy, even outside of the pandemic, could positively influence the epidemiology of infectious and allergic diseases in children, and healthcare system spending.

Assessing effective mask use by the public in two countries: an observational study

OBJECTIVES

During the COVID-19 pandemic wearing a mask in public has been recommended in some settings and mandated in others. How often this advice is followed, how well, and whether it inadvertently leads to more disease transmission opportunities due to a combination of improper use and physical distancing lapses is unknown.

DESIGN

Cross-sectional observational study performed in June-August 2020.

SETTING

Eleven outdoor and indoor public settings (some with mandated mask use, some without) each in Toronto, Ontario, and in Portland, Oregon.

PARTICIPANTS

All passers-by in the study settings.

OUTCOME MEASURES

Mask use, incorrect mask use, and number of breaches (ie, coming within 2 m of someone else where both parties were not properly masked).

RESULTS

We observed 36 808 persons, the majority of whom were estimated to be aged 31-65 years (49%). Two-thirds (66.7%) were wearing a mask and 13.6% of mask-wearers wore them incorrectly. Mandatory mask-use settings were overwhelmingly associated with mask use (adjusted OR 79.2; 95% CI 47.4 to 135.1). Younger age, male sex, Torontonians, and public transit or airport settings (vs in a store) were associated with lower adjusted odds of wearing a mask. Mandatory mask-use settings were associated with lower adjusted odds of mask error (OR 0.30; 95% CI 0.14 to 0.73), along with female sex and Portland subjects. Subjects aged 81+ years (vs 31-65 years) and those on public transit and at the airport (vs stores) had higher odds of mask errors. Mask-wearers had a large reduction in adjusted mean number of breaches (rate ratio (RR) 0.19; 95% CI 0.17 to 0.20). The 81+ age group had the largest association with breaches (RR 7.77; 95% CI 5.32 to 11.34).

CONCLUSIONS

Mandatory mask use was associated with a large increase in mask-wearing. Despite 14% of them wearing their masks incorrectly, mask users had a large reduction in the mean number of breaches (disease transmission opportunities). The elderly and transit users may warrant public health interventions aimed at improving mask use.

Importance of public health tools in emerging infectious diseases

Jin-Ling Tang and Li-Ming Li argue that despite the lure of vaccines and new drugs, established public health measures will remain our best tool to control covid-19 and future epidemics

Effect of Wearing Medical Masks on Perioperative Respiratory Complications in Older Adults with Hip Fracture: A Retrospective Cohort Study

Purpose

Respiratory complication is one of the major challenges in the treatment of older adults with hip fractures. However, no study so far has investigated the effect of wearing medical masks on the prevention of perioperative respiratory complications in these patients.

Patients and Methods

In this retrospective cohort study, 1016 consecutive patients aged ≥65 years with hip fractures were included and assigned to two groups: the control group and the observation group. The two groups received the same perioperative management modalities. In addition, patients in the observation group were asked to wear medical masks for protection. Data of patients’ demographics, fracture type, surgical methods, comorbidities, the incidence of perioperative respiratory and other complications, and hospital outcomes were collected and compared between the two groups. Subgroup analyses were also performed stratified by fracture types.

Results

A total of 1016 patients (292 females and 724 males) with a mean age of 79.4±7.3 years were analyzed in the study, including 533 in the control group and 483 in the observation group. The overall incidence of perioperative respiratory complication, and the incidence of pulmonary infection, respiratory failure and arrhythmia in the observation group were significantly lower than the control group, especially in winter and spring. There was no difference in other complications, hospital length of stay, and total hospital costs. Further subgroup analyses showed that the incidence of heart failure and arrhythmia in the observation group was lower than that in the control group for patients with femoral neck fractures, which was different from patients with intertrochanteric fractures.

Conclusion

The incidence of perioperative respiratory complications, including pulmonary infection and respiratory failure, could be reduced in older adults with hip fractures by strengthening personal protection, including wearing medical masks, especially in winter and spring. Wearing medical masks could also effectively reduce the incidence of perioperative heart failure and arrhythmia in femoral neck fracture patients and do not increase the incidence of other complications and the burden of hospitalization.

Unmasking the mask studies: why the effectiveness of surgical masks in preventing respiratory infections has been underestimated

BACKGROUND

Pre-pandemic empirical studies have produced mixed statistical results on the effectiveness of masks against respiratory viruses, leading to confusion that may have contributed to organizations such as the WHO and CDC initially not recommending that the general public wear masks during the coronavirus disease 2019 pandemic.

METHODS

A threshold-based dose-response curve framework is used to analyse the effects of interventions on infection probabilities for both single and repeated exposure events. Empirical studies on mask effectiveness are evaluated with a statistical power analysis that includes the effect of adherence to mask usage protocols.

RESULTS

When the adherence to mask usage guidelines is taken into account, the empirical evidence indicates that masks prevent disease transmission: all studies we analysed that did not find surgical masks to be effective were under-powered to such an extent that even if masks were 100% effective, the studies in question would still have been unlikely to find a statistically significant effect. We also provide a framework for understanding the effect of masks on the probability of infection for single and repeated exposures. The framework demonstrates that masks can have a disproportionately large protective effect and that more frequently wearing a mask provides super-linearly compounding protection.

CONCLUSIONS

This work shows (1) that both theoretical and empirical evidence is consistent with masks protecting against respiratory infections and (2) that non-linear effects and statistical considerations regarding the percentage of exposures for which masks are worn must be taken into account when designing empirical studies and interpreting their results.

Effects of N95 Mask Use on Pulmonary Function in Children

OBJECTIVE

To assess whether use of an N95 mask by children is associated with episodes of desaturation or respiratory distress.

STUDY DESIGN

Twenty-two healthy children were assigned at random to 1 of 2 groups: one group wearing N95 masks without an exhalation valve and the other group wearing N95 masks with an exhalation valve. We tracked changes in partial pressure of end-tidal carbon dioxide (P_ETCO2), oxygen saturation, pulse rate, and respiratory rate over 72 minutes of mask use. All subjects were monitored every 15 minutes, the first 30 minutes while not wearing a mask and the next 30 minutes while wearing a mask. They then performed a 12-minute walking test.

RESULTS

The children did not experience a statistically significant change in oxygen saturation or pulse rate during the study. There were significant increases in respiratory rate and P_ETCO2 in the children wearing an N95 mask without an exhalation valve, whereas these increases were seen in the children wearing a mask with an exhalation valve only after the walking test.

CONCLUSIONS

The use of an N95 mask could potentially cause breathing difficulties in children if the mask does not have an exhalation valve, particularly during a physical activity. We believe that wearing a surgical mask may be more appropriate for children.

Universal use of surgical masks is tolerated and prevents respiratory viral infection in stem cell transplant recipients

Prevention of respiratory viral infection in stem cell transplant patients is important due to its high risk of adverse outcome. This single-centre, mixed methods study, conducted before the severe acute respiratory syndrome coronavirus-2 pandemic, explored the barriers and facilitators to a policy of universal mask use by visitors and healthcare workers, and examined the impact of the first year of introduction of the policy on respiratory viral infection rates compared with preceding years, adjusted for overall incidence. Education around universal mask use was highlighted as being particularly important in policy implementation. A significant decrease in respiratory viral infection was observed following introduction.

Annual review of selected scientific literature: A report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry

The Scientific Investigation Committee of the American Academy of Restorative Dentistry offers this review of the 2020 professional literature in restorative dentistry to inform busy dentists regarding noteworthy scientific and clinical progress over the past year. Each member of the committee brings discipline-specific expertise to this work to cover this broad topic. Specific subject areas addressed include prosthodontics; periodontics, alveolar bone, and peri-implant tissues; implant dentistry; dental materials and therapeutics; occlusion and temporomandibular disorders (TMDs); sleep-related breathing disorders; oral medicine and oral and maxillofacial surgery; and dental caries and cariology. The authors focused their efforts on reporting information likely to influence day-to-day dental treatment decisions with a keen eye on future trends in the profession. With the tremendous volume of dentistry and related literature being published today, this review cannot possibly be comprehensive. The purpose is to update interested readers and provide important resource material for those interested in pursuing greater detail. It remains our intent to assist colleagues in navigating the extensive volume of important information being published annually. It is our hope that readers find this work useful in successfully managing the dental patients they encounter.