Effectiveness of Surgical and Cotton Masks in Blocking SARS-CoV-2: A Controlled Comparison in 4 Patients

Impacts of indoor masks wearing on air contamination during 10-minute speaking in patients with SARS-CoV-2 omicron variant infection

In 10-minute speaking, N95 respirators significantly decreased SARS-CoV-2 emissions compared with no-mask wearing. However, SARS-CoV-2 was detected in the air even when wearing N95 and surgical masks in patients with high viral loads. Therefore, universal masking of infected and uninfected persons is important for preventing COVID-19 transmission via the air.

Analysis of the Types of Retracted COVID-19 Articles Published in PubMed-Listed Journals

OBJECTIVES

Periodically, medical publications are retracted. The reasons vary from minor situations, such as author attributions, which do not undermine the validity of the data or the analysis in the article, to serious reasons, such as fraud. Understanding the reasons for retraction can provide important information for clinicians, educators, researchers, journals, and editorial boards.

METHODS

The PubMed database was searched using the term "COVID-19" (coronavirus disease 2019) and the term limitation "retracted publication." The characteristics of the journals with retracted articles, the types of article, and the reasons for retraction were analyzed.

RESULTS

This search recovered 196 articles that had been retracted. These retractions were published in 179 different journals; 14 journals had >1 retracted article. The mean impact factor of these journals was 8.4, with a range of 0.32-168.9. The most frequent reasons for retractions were duplicate publication, concerns about data validity and analysis, concerns about peer review, author request, and the lack of permission or ethical violation. There were significant differences between the types of article and the reasons for retraction but no consistent pattern. A more detailed analysis of two particular retractions demonstrates the complexity and the effort required to make decisions about article retractions.

CONCLUSIONS

The retraction of published articles presents a significant challenge to journals, editorial boards, peer reviewers, and authors. This process has the potential to provide important benefits; it also has the potential to undermine confidence in both research and the editorial process.

An effective stacked autoencoder based depth separable convolutional neural network model for face mask detection

The COVID-19 pandemic has been infecting the entire world over the past years. To prevent the spread of COVID-19, people have acclimatised to the new normal, which includes working from home, communicating online, and maintaining personal cleanliness. There are numerous tools required to prepare to compact transmissions in the future. One of these elements for protecting individuals from fatal virus transmission is the mask. Studies have indicated that wearing a mask may help to reduce the risk of viral transmission of all kinds. It causes many public places to take efforts to ensure that its guests wear adequate face masks and keep a safe distance from one another. Screening systems need to be installed at the doors of businesses, schools, government buildings, private offices, and/or other important areas. A variety of face detection models have been designed using various algorithms and techniques. Most of the articles in the previously published research have not worked on dimensionality reduction in conjunction with depth-wise separable neural networks. The necessity of determining the identities of people who do not cover their faces when they are in public is the driving factor for the development of this methodology. This research work proposes a deep learning technique to determine if a person is wearing mask or not and identifies whether it is properly worn or not. Stacked Auto Encoder (SAE) technique is implemented by stacking the following components: Principal Component Analysis (PCA) and Depth-wise Separable Convolutional Neural Network (DWSC-NN). PCA is used to reduce the irrelevant features in the images and resulted high true positive rate in the detection of mask. We achieved an accuracy score of 94.16% and an F1 score of 96.009% by the application of the method described in this research.

Biased, wrong and counterfeited evidences published during the COVID-19 pandemic, a systematic review of retracted COVID-19 papers

In 2020 COVID-19 led to an unprecedented stream of papers being submitted to journals. Scientists and physicians all around the globe were in need for information about this new disease. In this climate, many articles were accepted after extremely fast peer-reviews to provide the scientific community with the latest discoveries and knowledge. Unfortunately, this also led to articles retraction due to authors' misconduct or errors in methodology and/or conclusions. The aim of this study is to investigate the number and characteristics of retracted papers, and to explore the main causes that led to retraction. We conducted a systematic review on retracted articles, using PubMed as data source. Our inclusion criteria were the following: English-language retracted articles that reported original data, results, opinions or hypotheses on COVID-19 and Sars-CoV-2. Twenty-seven retracted articles were identified, mainly reporting observational studies and opinion pieces. Many articles published during the first year of the pandemic have been retracted, mainly due to the authors' scientific misconduct. Duplications, plagiarism, frauds and absence of consent, were the main reasons for retractions. In modern medicine, researchers are required to publish frequently, and, especially during situations like the COVID-19 pandemic, when articles were rapidly published, gaps in peer-reviews system and in the path to scientific publication arose.

The Effect of Face Mask, Air Temperature, and Humidity on COVID-19 Transmission: A Systematic Review and Meta-analysis

Context: At the beginning of the COVID-19 pandemic, the effects of personal protective equipment (PPE) such as face masks, as well as environmental conditions, including temperature and humidity changes, were discussed due to the lack of effective medicine. Methods: The preferred reporting items for systematic reviews and meta-analysis (PRISMA) were implemented to conduct the present systematic review. The articles were selected from papers published by May 2020 in PubMed, Web of Science, Science Direct, Scopus, and Google Scholar databases. This meta-analysis estimated relative risk (RR) and pooled mean depicted as effect size (ES) using the random or fixed effects methods. Results: Ten studies met inclusion criteria, four of which addressed the effect of face masks and six of which dealt with temperature and humidity changes. This eta-analysis study showed that wearing face masks against the COVID-19 virus had a remarkable safety impact with RR (%95 CI) 8.56 (2.10 - 34.90), (I2 = %0.0 P = 0.999), and the pooled mean changes in temperature and humidity were estimated to be with ES (%95 CI) 9.03 (4.32 - 13.74), (I2 = %99.7, P = 0.0001) and with ES (%95 CI) 56.82 (46.12 - 67.51), ( I2 = %99.3, P = 0.0001) during the outbreak of the COVID-19. Conclusions: The findings of this systematic review and meta-analysis illustrate the effectiveness of face masks, in general, in preventing the transmission of the COVID-19 virus. According to the findings, temperature and humidity changes do not increase the outbreak of the COVID-19 virus.

The face behind the Covid-19 mask - A comprehensive review

The threat of epidemic outbreaks like SARS-CoV-2 is growing owing to the exponential growth of the global population and the continual increase in human mobility. Personal protection against viral infections was enforced using ambient air filters, face masks, and other respiratory protective equipment. Available facemasks feature considerable variation in efficacy, materials usage and characteristic properties. Despite their widespread use and importance, face masks pose major potential threats due to the uncontrolled manufacture and disposal techniques. Improper solid waste management enables viral propagation and increases the volume of associated biomedical waste at an alarming rate. Polymers used in single-use face masks include a spectrum of chemical constituents: plasticisers and flame retardants leading to health-related issues over time. Despite ample research in this field, the efficacy of personal protective equipment and its impact post-disposal is yet to be explored satisfactorily. The following review assimilates information on the different forms of personal protective equipment currently in use. Proper waste management techniques pertaining to such special wastes have also been discussed. The study features a holistic overview of innovations made in face masks and their corresponding impact on human health and environment. Strategies with SDG3 and SDG12, outlining safe and proper disposal of solid waste, have also been discussed. Furthermore, employing the CFD paradigm, a 3D model of a face mask was created based on fluid flow during breathing techniques. Lastly, the review concludes with possible future advancements and promising research avenues in personal protective equipment.

Aerosol capture and coronavirus spike protein deactivation by enzyme functionalized antiviral membranes

The airborne nature of coronavirus transmission makes it critical to develop new barrier technologies that can simultaneously reduce aerosol and viral spread. Here, we report nanostructured membranes with tunable thickness and porosity for filtering coronavirus-sized aerosols, combined with antiviral enzyme functionalization that can denature spike glycoproteins of the SARS-CoV-2 virus in low-hydration environments. Thin, asymmetric membranes with subtilisin enzyme and methacrylic functionalization show more than 98.90% filtration efficiency for 100-nm unfunctionalized and protein-functionalized polystyrene latex aerosol particles. Unfunctionalized membranes provided a protection factor of 540 ± 380 for coronavirus-sized particle, above the Occupational Safety and Health Administration's standard of 10 for N95 masks. SARS-CoV-2 spike glycoprotein on the surface of coronavirus-sized particles was denatured in 30 s by subtilisin enzyme-functionalized membranes with 0.02-0.2% water content on the membrane surface.

Evaluation of different types of face masks to limit the spread of SARS-CoV-2: a modeling study

We expanded a published mathematical model of SARS-CoV-2 transmission with complex, age-structured transmission and with laboratory-derived source and wearer protection efficacy estimates for a variety of face masks to estimate their impact on COVID-19 incidence and related mortality in the United States. The model was also improved to allow realistic age-structured transmission with a pre-specified R0 of transmission, and to include more compartments and parameters, e.g. for groups such as detected and undetected asymptomatic infectious cases who mask up at different rates. When masks are used at typically-observed population rates of 80% for those ≥ 65 years and 60% for those < 65 years, face masks are associated with 69% (cloth) to 78% (medical procedure mask) reductions in cumulative COVID-19 infections and 82% (cloth) to 87% (medical procedure mask) reductions in related deaths over a 6-month timeline in the model, assuming a basic reproductive number of 2.5. If cloth or medical procedure masks' source control and wearer protection efficacies are boosted about 30% each to 84% and 60% by cloth over medical procedure masking, fitters, or braces, the COVID-19 basic reproductive number of 2.5 could be reduced to an effective reproductive number ≤ 1.0, and from 6.0 to 2.3 for a variant of concern similar to delta (B.1.617.2). For variants of concern similar to omicron (B.1.1.529) or the sub-lineage BA.2, modeled reductions in effective reproduction number due to similar high quality, high prevalence mask wearing is more modest (to 3.9 and 5.0 from an R0 = 10.0 and 13.0, respectively). None-the-less, the ratio of incident risk for masked vs. non-masked populations still shows a benefit of wearing masks even with the higher R0 variants.

How effective are chest compressions when wearing mask? A randomised simulation study among first-year health care students during the COVID-19 pandemic

Background

The resuscitation guidelines provided for the COVID-19 pandemic strongly recommended wearing personal protective equipment. The current study aimed to evaluate and compare the effectiveness of chest compressions and the level of fatigue while wearing two different types of mask (surgical vs. cloth).

Methods

A randomized, non-inferiority, simulation study was conducted. Participants were randomised into two groups: surgical mask group (n = 108) and cloth mask group (n = 108). The effectiveness (depth and rate) of chest compressions was measured within a 2-min continuous chest-compression-only CPR session. Data were collected through an AMBU CPR Software, a questionnaire, recording vital parameters, and using Borg-scale related to fatigue (before and after the simulation). For further analysis the 2-min session was segmented into 30-s intervals.

Results

Two hundred sixteen first-year health care students participated in our study. No significant difference was measured between the surgical mask and cloth mask groups in chest compression depth (44.49 ± 10.03 mm vs. 45.77 ± 10.77 mm), rate (113.34 ± 17.76/min vs. 111.23 ± 17.51/min), and the level of fatigue (5.72 ± 1.69 vs. 5.56 ± 1.67) (p > 0.05 in every cases). Significant decrease was found in chest compression depth between the first 30-s interval and the second, third, and fourth intervals (p < 0.01).

Conclusion

The effectiveness of chest compressions (depth and rate) was non-inferior when wearing cloth mask compared to wearing surgical mask. However, the effectiveness of chest compressions decreased significantly in both groups during the 2-min chest-compression-only CPR session and did not reach the appropriate chest compression depth range recommended by the ERC.

Face Mask Practice and Technique During the COVID-19 Pandemic: A Nonrepresentative Cross-Sectional Study in Sudan

Background

The World Health Organization issued guidelines for face mask use in community settings during the current COVID-19 pandemic. However, data are limited on public compliance with those guidelines in Sudan. Therefore, this study assessed face mask-wearing practice and technique during the COVID-19 pandemic among residents of Sudan.

Methods

A cross-sectional study was conducted from July to September 2021 among Sudanese aged ≥18 years. A web-based questionnaire was shared through different social media platforms. Personal characteristics, four knowledge-associated items, three attitude-associated items, one item concerning mask-wearing practice, and five items related to mask-wearing technique were determined. Univariate, bivariate, and multivariable analyses were performed using STATA v17.

Results

The survey included 1059 participants (48% males, 52% females) from different regions of Sudan. The overall mean ± SD was 3 ± 0.73 for knowledge of COVID-19 transmission; 2.3 ± 0.71 for attitude toward wearing face masks; 0.38 ± 0.49 for the practice of wearing a face mask; and 4.17 ± 0.97 for face mask-wearing technique. Approximately one-third (38%) of participants always wore a face mask during the pandemic, with age, sex, education level, family income, face mask attitude, occupation, and history of COVID-19 infection affecting the practice. All steps of face mask-wearing technique were performed by 46% of participants (59% performed hand hygiene before putting on a mask and 86% after removing it; 98% covered mouth and nose; 90% adjusted masks at the nose bridge, and 84% tied masks securely), and associated with age, occupation, family income, history of COVID-19 infection, and face-mask attitude.

Conclusion

Although knowledge and attitude were relatively good, the practice of wearing a face mask and using proper techniques among participants were low. To ensure optimal face mask use and proper mask-wearing techniques, educational intervention and establishing governmental regulations are highly recommended.

State-of-the-Art and Projected Developments of Nanofiber Filter Material for Face Mask Against COVID-19

BACKGROUND

The Covid-19 epidemic was declared a pandemic by the World Health Organization in March 2020. It is difficult to foresee the future length and severity; it may extend to weeks, months, or even years to deplete the energy and resources of the health care facilities and the providers as there is marginal to no pharmacological medication available to treat the Covid-19. Unless an effective pharmacological treatment such as medicines and vaccines is developed and released publicly, wearing protective face masks and protecting personal health and hygiene is merely a choice to avoid the Covid-19 spread. This review summarizes the background knowledge on the Covid-19 disease and currently available face masks for highly infectious disease primary prevention. According to recent studies of Covid-19 prevention, diagnosis, and treatment, nanotechnologists have provided a revolutionary approach that involves both pharmacological and non-pharmacological steps, one of which is the use of nanofibers in facemasks and respirators.

METHODS

Various researches carried out in the field of nanomask and patented reports based on the application of nanomask were reviewed.

CONCLUSION

The most recent developments of nanofibers, including research publications, patents and commercial products in Covid-19 prevention, are extensively reviewed from scientific literature and appropriately represented in this study.

Inconsistent and incomplete retraction of published research: A cross-sectional study on Covid-19 retractions and recommendations to mitigate risks for research, policy and practice

BACKGROUND

Retraction of published research can reduce the dissemination of incorrect or misleading information, but concerns have been raised about the clarity and rigor of the retraction process. Failure to clearly and consistently retract research has several risks, for example discredited or erroneous research may inform health research studies (e.g. clinical trials), policies and practices, potentially rendering these unreliable.

OBJECTIVE

To investigate consistency and clarity of research retraction, based on a case study of retracted Covid-19 research.

STUDY DESIGN

A cross-sectional study of retracted Covid-19 articles reporting empirical research findings, based on searches of Medline, Embase and Scopus on 10th July and 19th December 2020.

KEY RESULTS

We included 46 retracted Covid-19 articles. The number eligible for inclusion nearly doubled, from 26 to 46, in five months. Most articles (67%) were retracted from scientific journals and the remainder from preprint servers. Key findings: (1) reasons for retraction were not reported in 33% (15/46) of cases; (2) time from publication to retraction could not be determined in 43% (20/46) of cases; (3) More than half (59%) of retracted Covid-19 articles (27/46) remained available as original unmarked electronic documents after retraction (33% as full text and 26% as an abstract only). Sources of articles post-retraction were preprint servers, ResearchGate and, less commonly, websites including PubMed Central and the World Health Organization. A retracted journal article which controversially claimed a link between 5G technology and Covid-19 remains available in its original full text from at least 60 different websites.

CONCLUSIONS

The retraction process is inconsistent and often ambiguous, with more than half of retracted Covid-19 research articles remaining available, unmarked, from a wide range of online sources. There is an urgent need to improve guidance on the retraction process and to extend this to cover preprint servers. We provide structured recommendations to address these concerns and to reduce the risks that arise when retracted research is inappropriately cited.

Influence of Wearing Surgical Mask on Interpersonal Space Perception Between Mainland Chinese and Taiwanese People

Wearing face masks and maintaining social distancing of 1.5m are two common preventive measures against the spread of COVID-19. However, the interaction of these preventive measures in interpersonal space (IPS) perception remains unknown. This study evaluated the effects of wearing surgical masks, sex dyads, and approaching patterns on IPS judgment. Data were collected from participants from Mainland China (n=100) and Taiwan (n=100) through an online survey. Therefore, the regional differences were also examined. A smaller IPS was observed when participants faced confederates wearing surgical masks than in the no-mask condition. Female dyads tended to maintain a smaller IPS than did both male and mixed-sex dyads, and Taiwanese participants maintained a significantly larger IPS than did Mainland Chinese participants. No significant difference was observed between the active and passive pattern. Moreover, the interaction between region and mask had a significant influence on IPS perception. Among all test combinations, only the IPS perceived by Taiwanese participants facing confederates without surgical masks exceeded 1.5m. This study revealed that the wearing of surgical masks for health protection during the pandemic influences IPS perception in different regions. The current findings may provide useful information for social interaction and environmental design during the COVID-19 pandemic.

A pre-systematic review on the use of masks as a protection material for SARS-COV-2 during the COVID-19 pandemic

BACKGROUND

Coronavirus disease 2019 (COVID-19) was first reported in Wuhan, China on 31 December 2019.

AIMS

to review, analyse and discuss all works about the wearing and development of facemasks as potential protection against SARS-COV-2 during the COVID-19 pandemic.

METHODS

PubMed, SciELO, Google Scholar and DOAJ were browsed.

KEYWORDS

"mask and (SARS or Cov)" (1 August 2019 to 12 April 2020).

INCLUSION CRITERIA

original research. PRISMA criteria were followed.

RESULTS

Twenty-one works were selected. Identified topics: effectiveness of protective equipment/devices (PE) (n = 3), universal wearing of facemasks plus other protective measures in the community (n = 3), impact of infection control measures on hospitals and epidemiological tracing (n = 3), development of new PE (n = 2), sanitisation of facemasks (n = 4), clinical guidance (n = 4) and questionnaires (n = 2).

DISCUSSION

It seems that the effectiveness of PE, namely facemasks, is not fully known. Universal wearing of facemasks may be simultaneously recommended with other protective measures. Nosocomial and community infections seem to be preventable. New PE, methods of facemask sanitisation and clinical guidance are emerging, but caution is recommended regarding their adoption, revision and monitoring by international boards and institutions. Questionnaires are useful tools for collecting citizens' opinions on implementing public health measures, and thus contribute to mitigating the COVID-19 pandemic.

CONCLUSIONS

Universal wearing of facemasks in the community is likely to be recommended during the COVID-19pandemic. Since SARS-COV-2 is highly contagious, a set of measures should be considered. Facemask sanitisation is possible, but standardised procedures are lacking. New PE is emerging and requires detailed regulatory approval. It is advisable to monitor public opinion.

Rationale for Mass Masking in Controlling the COVID-19 Pandemic

The rapid spread of the coronavirus disease 2019 (COVID-19) into a global pandemic caught the world unprepared. Previously effective measures for containing disease outbreaks were overwhelmed, necessitating strict controls such as lockdowns or curfews. Among the disease control interventions, community mass masking was one of the highly controversial issues with differing opinions on its indications or effectiveness from different health authorities around the world. Regions where community mass masking was timely introduced were associated with lower transmission rates, and more effective disease control. In this article, we discuss the evidence on the effectiveness, and rationale for community mass masking to prevent the COVID-19 transmission. Areas for further research to define the role of mass masking in light of the COVID-19 pandemic will be suggested. This would help policy makers in formulating mass masking policies.

A comprehensive review of various categories of face masks resistant to Covid-19

The science about the usage of face masks by the common public to avert COVID-19 transmission is proceeding swiftly. A primary route of transmission of COVID-19 is probably through small respiratory droplets, and it is transmissible from asymptomatic and pre-symptomatic individuals. According to the World Health Organization, wearing a mask in public can help reduce the transmission of the COVID-19 virus. Different categories and types of masks and their usage are reviewed in this work. In a nutshell, this review work elucidates the aspects of utilizing the various face masks along with all possibilities to fight against the ongoing pandemic of COVID-19.

SARS-CoV-2: a systematic review of indoor air sampling for virus detection

In a post-pandemic scenario, indoor air monitoring may be required seeking to safeguard public health, and therefore well-defined methods, protocols, and equipment play an important role. Considering the COVID-19 pandemic, this manuscript presents a literature review on indoor air sampling methods to detect viruses, especially SARS-CoV-2. The review was conducted using the following online databases: Web of Science, Science Direct, and PubMed, and the Boolean operators "AND" and "OR" to combine the following keywords: air sampler, coronavirus, COVID-19, indoor, and SARS-CoV-2. This review included 25 published papers reporting sampling and detection methods for SARS-CoV-2 in indoor environments. Most of the papers focused on sampling and analysis of viruses in aerosols present in contaminated areas and potential transmission to adjacent areas. Negative results were found in 10 studies, while 15 papers showed positive results in at least one sample. Overall, papers report several sampling devices and methods for SARS-CoV-2 detection, using different approaches for distance, height from the floor, flow rates, and sampled air volumes. Regarding the efficacy of each mechanism as measured by the percentage of investigations with positive samples, the literature review indicates that solid impactors are more effective than liquid impactors, or filters, and the combination of various methods may be recommended. As a final remark, determining the sampling method is not a trivial task, as the samplers and the environment influence the presence and viability of viruses in the samples, and thus a case-by-case assessment is required for the selection of sampling systems.

Increase in SARS-CoV-2 infected biomedical waste among low middle-income countries: environmental sustainability and impact with health implications

Studies have shown that severe acute respiratory syndrome corona virus-2 (SARS-CoV-2) is a highly infectious disease, with global deaths rising to about 360,438 as of 28 May 2020. Different countries have used various approaches such as lockdown, social distancing, maintenance of personal hygiene, and increased establishment of testing and isolation centers to manage the pandemic. Poor biomedical waste (BMW) management, treatment, and disposal techniques, especially SARS-CoV-2 infected BMW, may threaten the environmental and public health in most developing countries and, by extension, impact the economic status of individuals and the nation at large. This may increase the potential for the transmission of air/blood body fluid-borne pathogens, increase the growth of microorganisms, risk of mutagenesis, and upsurge of more virulent strain. In contrast, uncontrolled substandard burning could increase the potential spread of nosocomial infection and environmental exposure to toxic organic compounds, heavy metals, radioactive, and genotoxic bio-aerosols which might be present in the gaseous, liquid, and solid by-products. The paucity of understanding of pathophysiology and management of the SARS-CoV-2 pandemic has also necessitated the need to put in place appropriate disposal techniques to cater for the sudden increase in the global demand for personal protective equipment (PPE) and pharmaceutical drugs to manage the pandemic and to reduce the risk of preventable infection by the waste. Therefore, there is a need for adequate sensitization, awareness, and environmental monitoring of the impacts of improper handling of SARS-CoV-2 infected BMWs. Hence, this review aimed to address the issues relating to the improper management of increased SARS-CoV-2 infected BMW in low middle-income countries (LMICs).

Face mask wearing during the COVID-19 pandemic: comparing perceptions in China and three European countries

Face mask recommendations are conflicting across the world during the coronavirus disease 2019 (COVID-19) pandemic. While universal face mask wearing is a useful non-pharmaceutical preventive strategy, little is known about the perception of mask wearing during a pandemic. This study aimed to examine people’s face mask use in China and Europe. An online survey was conducted among residents in China, Austria, Germany, and Switzerland from the 1st to 10th of April 2020. With a convenience sampling approach, 655 valid answers were received including 267 Chinese and 388 European residents (261 from Austria, 101 from Germany, 26 from Switzerland). Self-reported face mask wearing status and related perceptions were assessed. Compared with the Europeans, Chinese participants showed a stronger pro-masking tendency. Subjective norm was an important predictor of face mask wearing in public. Wearing of face masks in the Chinese sample was also associated with risk perception as well as obedience to advice from local health authority. Discrepancies in face mask wearing suggest that targeted measures to promote face mask wearing are needed in Europe. Globally coordinated guidelines on pandemics are also warranted to face the next waves of COVID-19 and other infectious respiratory diseases.

Methodology for risk assessment of COVID-19 pandemic propagation

This paper proposes a methodology to perform risk analysis of the virus spread. It is based on the coupling between CFD modelling of bioaerosol dispersion to the calculation of probability of contact events. CFD model of near-field sneeze droplets dispersion is developed to build the SARS-CoV-2 effect zones and to adequately capture the safe distance. The most shared classification of droplets size distribution of sneezes was used.

Droplets were modeled through additive heating/evaporation/boiling laws and their impact on the continuous phase was examined. Larger droplets move behind the droplet nuclei front and exhibit greater vertical drop due to the effect of gravity. CFD simulations provided the iso-risk curves extension (i.e., the maximum distance as well as the angle) enclosed by the incident outcome effect zone. To calculate the risk indexes, a fault tree was developed and the probability of transmission assuming as of the top event “COVID-19 infection” was calculated starting from the virus spread curve, as main base case. Four phases of virus spread evolution were identified: initiation, propagation, generalised propagation and termination. For each phase, the maximum allowable close contact was computed, being fixed the values of the acceptable risk index. In particular, it was found that during the propagation case, the maximum allowable close contacts is two, suggesting that at this point lockdown should be activated. The here developed methodology could drive policy containment design to curb spread COVID-19 infection.

Thoracic Surgery in the COVID-19 Pandemic: A Novel Approach to Reach Guideline Consensus

The COVID-19 pandemic challenges international and national healthcare systems. In the field of thoracic surgery, procedures may be deferred due to mandatory constraints of the access to diagnostics, staff and follow-up facilities. There is a lack of prospective data on the management of benign and malignant thoracic conditions in the pandemic. Therefore, we derived recommendations from 14 thoracic societies to address key questions on the topic of COVID-19 in the field of thoracic surgery. Respective recommendations were extracted and the degree of consensus among different organizations was calculated. A high degree of consensus was found to temporarily suspend non-critical elective procedures or procedures for benign conditions and to prioritize patients with symptomatic or advanced cancer. Prior to hospitalization, patients should be screened for respiratory symptoms indicating possible COVID-19 infection and most societies recommended to screen all patients for COVID-19 prior to admission. There was a weak consensus on the usage of serology tests and CT scans for COVID-19 diagnostics. Nearly all societies suggested to postpone elective procedures in patients with suspected or confirmed COVID-19 and recommended constant reevaluation of these patients. Additionally, we summarized recommendations focusing on precautions in the theater and the management of chest drains. This study provides a novel approach to informed guidance for thoracic surgeons during the COVID-19 pandemic in the absence of scientific evidence-based data.

Open science saves lives: lessons from the COVID-19 pandemic

In the last decade Open Science principles have been successfully advocated for and are being slowly adopted in different research communities. In response to the COVID-19 pandemic many publishers and researchers have sped up their adoption of Open Science practices, sometimes embracing them fully and sometimes partially or in a sub-optimal manner. In this article, we express concerns about the violation of some of the Open Science principles and its potential impact on the quality of research output. We provide evidence of the misuses of these principles at different stages of the scientific process. We call for a wider adoption of Open Science practices in the hope that this work will encourage a broader endorsement of Open Science principles and serve as a reminder that science should always be a rigorous process, reliable and transparent, especially in the context of a pandemic where research findings are being translated into practice even more rapidly. We provide all data and scripts at https://osf.io/renxy/ .

Ethical communication to patient & society: a critical responsibility in COVID-19 pandemic

The article's abstract is not available.

Clinical Research Redirection and Optimization During a Pandemic

The COVID-19 pandemic has seen many hurdles to crucial research processes, in particular those that depend on personnel interactions, in providing safeguards against the incipient infectious disease. At the same time, there was a rapid redirection of research, driven by popular and social media and demand for pandemic-related content, to the detriment of non-COVID-19 research and perhaps to COVID-19 research itself. This article provides historical context to research redirection and discusses approaches to optimizing research methodology in the setting of COVID-19 pandemic.

Can tweets be used to detect problems early with scientific papers? A case study of three retracted COVID-19/SARS-CoV-2 papers

Methodological mistakes, data errors, and scientific misconduct are considered prevalent problems in science that are often difficult to detect. In this study, we explore the potential of using data from Twitter for discovering problems with publications. In this case study, we analyzed tweet texts of three retracted publications about COVID-19 (Coronavirus disease 2019)/SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) and their retraction notices. We did not find early warning signs in tweet texts regarding one publication, but we did find tweets that casted doubt on the validity of the two other publications shortly after their publication date. An extension of our current work might lead to an early warning system that makes the scientific community aware of problems with certain publications. Other sources, such as blogs or post-publication peer-review sites, could be included in such an early warning system. The methodology proposed in this case study should be validated using larger publication sets that also include a control group, i.e., publications that were not retracted.

Efficacy of Face Masks Used in Uganda: A Laboratory-Based Inquiry during the COVID-19 Pandemic

With shortages of face masks being reported worldwide, it is critical to consider alternatives to commercially manufactured face masks. This study aimed to test and compare the efficacy of various makes of locally made or homemade cloth face masks obtained from face-mask vendors in Kampala, Uganda, during the COVID-19 pandemic. The testing was performed to assess the bacterial filtration efficiency (BFE), breathability, distance-dependent fitness, and reusability of the locally made or homemade cloth face masks, while considering the most commonly used non-published face-mask decontamination approaches in Uganda. During laboratory experimentation, modified protocols from various face-mask testing organizations were adopted. Ten different face-mask types were experimented upon; each face-mask type was tested four times for every single test, except for the decontamination protocols involving washing where KN95 and surgical face masks were not included. Among the locally made or homemade cloth face masks, the double-layered cloth face masks (described as F) had better BFE and distance-dependent fitness characteristics, they could be reused, and had good breathability, than the other locally made or homemade cloth face masks. Despite these good qualities, the certainty of these face masks protecting wearers against COVID-19 remains subject to viral filtration efficiency testing.

Facemask use in community settings to prevent respiratory infection transmission: A rapid review and meta-analysis

INTRODUCTION

Synthesis of the available evidence on the effectiveness of medical and cloth facemask use by the general public in community settings is required to learn lessons for future respiratory epidemics/pandemics.

METHOD

Search terms relating to facemasks, infection and community settings were used for PubMed, the Cochrane Library Database and Google Scholar. A meta-analysis was conducted using a random-effects model.

RESULTS

The review included 12 primary studies on the effectiveness of medical facemask use to prevent influenza, influenza-like illness, SARS-CoV, and SARS-CoV-2 transmission. The meta-analysis demonstrated that facemask use significantly reduces the risk of transmitting these respiratory infections (pooled OR = 0.66, 95% CI 0.54-0.81). Of the 12 studies, 10 clinical trials suggested that respiratory infection incidence is lower with high medical facemask compliance, early use and use in combination with intensive hand hygiene. One cohort study conducted during the SARS-CoV-2 pandemic demonstrated that facemasks are effective in reducing SARS-CoV-2 transmission when used before those who are infected develop symptoms. One case-control study reported that controls used medical facemasks more often than cases infected with SARS-CoV (p <  0.05). No primary study on cloth facemask effectiveness to prevent respiratory infection transmission was found.

CONCLUSION

Based on the available evidence, medical facemask use by healthy and sick individuals is recommended for preventing respiratory infection transmission in community settings. Medical facemask effectiveness is dependent on compliance and utilization in combination with preventive measures such as intensive hand hygiene. No direct evidence is currently available in humans supporting the recommendation of cloth facemask use to prevent respiratory infection transmission.

Community practice of using face masks for the prevention of COVID-19 in Saudi Arabia

Community face masking is possibly of great value in reducing COVID-19 transmission, especially when universally adopted with high compliance. The aim of this study is to investigate the knowledge, common misconceptions, barriers, and the compliance of the community with the use of face masks for the prevention of COVID-19. A validated questionnaire was administered to the participants through a web link by using various social media. The collected data were statistically analyzed for significant differences according to demographic variables. The average knowledge of face masks and their role in preventing COVID-19 transmission was 95.64%, with no differences among most of the demographical factors. Older groups and females demonstrated a better attitude towards wearing face masks than other groups did (p<0.001). Another significant difference in the participant's attitude was noticed between the various educational levels, employment, and nationality (p<0.001). Of the total respondents, 88.2% encouraged wearing face masks. Misconceptions about wearing face masks were very low. The frequency of wearing face masks at public places, workplaces, or social gatherings was 87.2%, 80.5%, and 47.5% respectively. There was a significant variation in the compliance with wearing face masks between the various groups based on age, gender, nationality, and employment status (p<0.001). The inconvenience in wearing face masks was reported by 36.3%. Face irritation and ear pain were reported by 70.2% and 43.5%, respectively. The inconvenience of wearing face masks with eyeglasses was reported by 44.3% of those wearing eyeglasses. In general, the study demonstrated a good attitude among participants towards wearing face masks. Although the respondents in the study were aware of the benefits of wearing face masks, the barriers may have decreased their desire to do so. These barriers include difficulty in breathing, discomfort, face irritation, and ear pain.

Why does the spread of COVID-19 vary greatly in different countries? Revealing the efficacy of face masks in epidemic prevention

The severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) is highly contagious, and the coronavirus disease 2019 (COVID-19) pandemic caused by it has forced many countries to adopt 'lockdown' measures to prevent the spread of the epidemic through social isolation of citizens. Some countries proposed universal mask wearing as a protection measure of public health to strengthen national prevention efforts and to limit the wider spread of the epidemic. In order to reveal the epidemic prevention efficacy of masks, this paper systematically evaluates the experimental studies of various masks and filter materials, summarises the general characteristics of the filtration efficiency of isolation masks with particle size, and reveals the actual efficacy of masks by combining the volume distribution characteristics of human exhaled droplets with different particle sizes and the SARS-CoV-2 virus load of nasopharynx and throat swabs from patients. The existing measured data show that the filtration efficiency of all kinds of masks for large particles and extra-large droplets is close to 100%. From the perspective of filtering the total number of pathogens discharged in the environment and protecting vulnerable individuals from breathing live viruses, the mask has a higher protective effect. If considering the weighted average filtration efficiency with different particle sizes, the filtration efficiencies of the N95 mask and the ordinary mask are 99.4% and 98.5%, respectively. The mask can avoid releasing active viruses to the environment from the source of infection, thus maximising the protection of vulnerable individuals by reducing the probability of inhaling a virus. Therefore, if the whole society strictly implements the policy of publicly wearing masks, the risk of large-scale spread of the epidemic can be greatly reduced. Compared with the overall cost of social isolation, limited personal freedoms and forced suspension of economic activities, the inconvenience for citizens caused by wearing masks is perfectly acceptable.

Stability of SARS-CoV-2 on critical personal protective equipment

The spread of COVID-19 in healthcare settings is concerning, with healthcare workers representing a disproportionately high percentage of confirmed cases. Although SARS-CoV-2 virus has been found to persist on surfaces for a number of days, the extent and duration of fomites as a mode of transmission, particularly in healthcare settings, has not been fully characterized. To shed light on this critical matter, the present study provides the first comprehensive assessment of SARS-CoV-2 stability on experimentally contaminated personal protective equipment (PPE) widely used by healthcare workers and the general public. Persistence of viable virus was monitored over 21 days on eight different materials, including nitrile medical examination gloves, reinforced chemical resistant gloves, N-95 and N-100 particulate respirator masks, Tyvek, plastic, cotton, and stainless steel. Unlike previous reports, viable SARS-CoV-2 in the presence of a soil load persisted for up to 21 days on experimentally inoculated PPE, including materials from filtering facepiece respirators (N-95 and N-100 masks) and a plastic visor. Conversely, when applied to 100% cotton fabric, the virus underwent rapid degradation and became undetectable by TCID₅₀ assay within 24 h. These findings underline the importance of appropriate handling of contaminated PPE during and following use in high-risk settings and provide interesting insight into the potential utility of cotton in limiting COVID-19 transmission.

Stability of SARS-CoV-2 on critical personal protective equipment

The spread of COVID-19 in healthcare settings is concerning, with healthcare workers representing a disproportionately high percentage of confirmed cases. Although SARS-CoV-2 virus has been found to persist on surfaces for a number of days, the extent and duration of fomites as a mode of transmission, particularly in healthcare settings, has not been fully characterized. To shed light on this critical matter, the present study provides the first comprehensive assessment of SARS-CoV-2 stability on experimentally contaminated personal protective equipment (PPE) widely used by healthcare workers and the general public. Persistence of viable virus was monitored over 21 days on eight different materials, including nitrile medical examination gloves, reinforced chemical resistant gloves, N-95 and N-100 particulate respirator masks, Tyvek, plastic, cotton, and stainless steel. Unlike previous reports, viable SARS-CoV-2 in the presence of a soil load persisted for up to 21 days on experimentally inoculated PPE, including materials from filtering facepiece respirators (N-95 and N-100 masks) and a plastic visor. Conversely, when applied to 100% cotton fabric, the virus underwent rapid degradation and became undetectable by TCID₅₀ assay within 24 h. These findings underline the importance of appropriate handling of contaminated PPE during and following use in high-risk settings and provide interesting insight into the potential utility of cotton in limiting COVID-19 transmission.

Stability of SARS-CoV-2 on critical personal protective equipment

The spread of COVID-19 in healthcare settings is concerning, with healthcare workers representing a disproportionately high percentage of confirmed cases. Although SARS-CoV-2 virus has been found to persist on surfaces for a number of days, the extent and duration of fomites as a mode of transmission, particularly in healthcare settings, has not been fully characterized. To shed light on this critical matter, the present study provides the first comprehensive assessment of SARS-CoV-2 stability on experimentally contaminated personal protective equipment (PPE) widely used by healthcare workers and the general public. Persistence of viable virus was monitored over 21 days on eight different materials, including nitrile medical examination gloves, reinforced chemical resistant gloves, N-95 and N-100 particulate respirator masks, Tyvek, plastic, cotton, and stainless steel. Unlike previous reports, viable SARS-CoV-2 in the presence of a soil load persisted for up to 21 days on experimentally inoculated PPE, including materials from filtering facepiece respirators (N-95 and N-100 masks) and a plastic visor. Conversely, when applied to 100% cotton fabric, the virus underwent rapid degradation and became undetectable by TCID₅₀ assay within 24 h. These findings underline the importance of appropriate handling of contaminated PPE during and following use in high-risk settings and provide interesting insight into the potential utility of cotton in limiting COVID-19 transmission.

Face Mask Use in the Community for Reducing the Spread of COVID-19: A Systematic Review

Background: Evidence is needed on the effectiveness of wearing face masks in the community to prevent SARS-CoV-2 transmission. Methods: Systematic review and meta-analysis to investigate the efficacy and effectiveness of face mask use in a community setting and to predict the effectiveness of wearing a mask. We searched MEDLINE, EMBASE, SCISEARCH, The Cochrane Library, and pre-prints from inception to 22 April 2020 without restriction by language. We rated the certainty of evidence according to Cochrane and GRADE approach. Findings: Our search identified 35 studies, including three randomized controlled trials (RCTs) (4,017 patients), 10 comparative studies (18,984 patients), 13 predictive models, nine laboratory experimental studies. For reducing infection rates, the estimates of cluster-RCTs were in favor of wearing face masks vs. no mask, but not at statistically significant levels (adjusted OR 0.90, 95% CI 0.78-1.05). Similar findings were reported in observational studies. Mathematical models indicated an important decrease in mortality when the population mask coverage is near-universal, regardless of mask efficacy. In the best-case scenario, when the mask efficacy is at 95%, the R0 can fall to 0.99 from an initial value of 16.90. Levels of mask filtration efficiency were heterogeneous, depending on the materials used (surgical mask: 45-97%). One laboratory study suggested a viral load reduction of 0.25 (95% CI 0.09-0.67) in favor of mask vs. no mask. Interpretation: The findings of this systematic review and meta-analysis support the use of face masks in a community setting. Robust randomized trials on face mask effectiveness are needed to inform evidence-based policies. PROSPERO registration: CRD42020184963.

The Potential for Cloth Masks to Protect Health Care Clinicians From SARS-CoV-2: A Rapid Review

PURPOSE

The coronavirus disease 2019 (COVID-19) pandemic has led at times to a scarcity of personal protective equipment, including medical masks, for health care clinicians, especially in primary care settings. The objective of this review was to summarize current evidence regarding the use of cloth masks to prevent respiratory viral infections, such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), among health care clinicians.

METHODS

We searched 5 databases, the Centers for Disease Control and Prevention website, and the reference lists of identified articles on April 3, 2020. All identified publications were independently screened by 2 reviewers. Two authors independently extracted data and graded the studies. Randomized control trials (RCTs) were graded using the Consolidated Standards of Reporting Trials (CONSORT) checklist, and observational and nonhuman subject studies were graded using 11 domains common across frequently used critical appraisal tools. All discrepancies were resolved by consensus.

RESULTS

Our search identified 136 original publications. Nine studies met inclusion criteria. We performed a qualitative synthesis of the data from these studies. Four nonrandomized trials, 3 laboratory studies, 1 single-case experiment, and 1 RCT were identified. The laboratory studies found that cloth materials provided measurable levels of particle filtration but were less efficacious at blocking biologic material than medical masks. The RCT found that cloth masks were associated with significantly more viral infections than medical masks.

CONCLUSIONS

The current literature suggests that cloth materials are somewhat efficacious in filtering particulate matter and aerosols but provide a worse fit and inferior protection compared to medical masks in clinical environments. The quality and quantity of literature addressing this question are lacking. Cloth masks lack evidence for adequate protection of health care clinicians against respiratory viral infections.

Management of COVID-19 Infection During Pregnancy, Labor, and Puerperium

This chapter describes the management of pregnant women infected with COVID-19. Management includes measures taken for prevention of infection and the currently available vaccines and possibility of their use during pregnancy. Special care of women during delivery including monitoring and treatment place and plan of treatment is discussed in details. Vaginal delivery measures were discussed including the proper analgesia. Special precautions during cesarean delivery including the anesthetic considerations were discussed. The management of the parturient in her postpartum period and care of the newborn were explained. Current evidences regarding breastfeeding and mother neonatal contact were discussed in detail. All the current available guidelines for management of COVID-19 pregnant patients with different disease severity starting from asymptomatic and passing through those with mild, moderate, and severe disease and reaching the management of critically ill patients were explained.

SARS-CoV-2 and Health Care Worker Protection in Low-Risk Settings: a Review of Modes of Transmission and a Novel Airborne Model Involving Inhalable Particles

Since the beginning of the COVID-19 pandemic, there has been intense debate over SARS-CoV-2's mode of transmission and appropriate personal protective equipment for health care workers in low-risk settings. The objective of this review is to identify and appraise the available evidence (clinical trials and laboratory studies on masks and respirators, epidemiological studies, and air sampling studies), clarify key concepts and necessary conditions for airborne transmission, and shed light on knowledge gaps in the field. We find that, except for aerosol-generating procedures, the overall data in support of airborne transmission-taken in its traditional definition (long-distance and respirable aerosols)-are weak, based predominantly on indirect and experimental rather than clinical or epidemiological evidence. Consequently, we propose a revised and broader definition of "airborne," going beyond the current droplet and aerosol dichotomy and involving short-range inhalable particles, supported by data targeting the nose as the main viral receptor site. This new model better explains clinical observations, especially in the context of close and prolonged contacts between health care workers and patients, and reconciles seemingly contradictory data in the SARS-CoV-2 literature. The model also carries important implications for personal protective equipment and environmental controls, such as ventilation, in health care settings. However, further studies, especially clinical trials, are needed to complete the picture.

The carnage of substandard research during the COVID-19 pandemic: a call for quality

Worldwide there are currently over 1200 research studies being performed on the topic of COVID-19. Many of these involve children and adults over age 65 years. There are also numerous studies testing investigational vaccines on healthy volunteers. No research team is exempt from the pressures and speed at which COVID-19 research is occurring. And this can increase the risk of honest error as well as misconduct. To date, 33 papers have been identified as unsuitable for public use and either retracted, withdrawn, or noted with concern. Asia is the source of most of these manuscripts (n=19; 57.6%) with China the largest Asian subgroup (n=11; 57.9%). This paper explores these findings and offers guidance for responsible research practice during pandemics.

SARS-CoV-2 Pandemic Impact on Pediatric Emergency Rooms: A Multicenter Study

From 9 March to 3 May 2020, lockdown was declared in Italy due to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. Our aim was to evaluate how the SARS-CoV-2 pandemic and related preventive strategies affected pediatric emergency rooms (ERs) during this period. We performed a retrospective cohort multicenter study, comparing the lockdown period to the corresponding period in 2019. We examined 15 Italian pediatric ERs in terms of visit rates, specific diagnoses (grouped as air communicable diseases and non-air communicable diseases), and triage categories. During the lockdown period, ER admissions decreased by 81% compared to 2019 (52,364 vs. 10,112). All ER specific diagnoses decreased in 2020 and this reduction was significantly higher for air communicable diseases (25,462 vs. 2934, p < 0.001). Considering the triage category, red codes remained similar (1% vs. 1%), yellow codes increased (11.2% vs. 22.3%), and green codes decreased (80.3% vs. 69.5%). We can speculate that social distancing and simple hygiene measures drastically reduced the spread of air communicable diseases. The increase in yellow codes may have been related to a delay in primary care and, consequently, in ER admissions.

Electrochemical SARS-CoV-2 Sensing at Point-of-Care and Artificial Intelligence for Intelligent COVID-19 Management

To manage the COVID-19 pandemic, development of rapid, selective, sensitive diagnostic systems for early stage β-coronavirus severe acute respiratory syndrome (SARS-CoV-2) virus protein detection is emerging as a necessary response to generate the bioinformatics needed for efficient smart diagnostics, optimization of therapy, and investigation of therapies of higher efficacy. The urgent need for such diagnostic systems is recommended by experts in order to achieve the mass and targeted SARS-CoV-2 detection required to manage the COVID-19 pandemic through the understanding of infection progression and timely therapy decisions. To achieve these tasks, there is a scope for developing smart sensors to rapidly and selectively detect SARS-CoV-2 protein at the picomolar level. COVID-19 infection, due to human-to-human transmission, demands diagnostics at the point-of-care (POC) without the need of experienced labor and sophisticated laboratories. Keeping the above-mentioned considerations, we propose to explore the compartmentalization approach by designing and developing nanoenabled miniaturized electrochemical biosensors to detect SARS-CoV-2 virus at the site of the epidemic as the best way to manage the pandemic. Such COVID-19 diagnostics approach based on a POC sensing technology can be interfaced with the Internet of things and artificial intelligence (AI) techniques (such as machine learning and deep learning for diagnostics) for investigating useful informatics via data storage, sharing, and analytics. Keeping COVID-19 management related challenges and aspects under consideration, our work in this review presents a collective approach involving electrochemical SARS-CoV-2 biosensing supported by AI to generate the bioinformatics needed for early stage COVID-19 diagnosis, correlation of viral load with pathogenesis, understanding of pandemic progression, therapy optimization, POC diagnostics, and diseases management in a personalized manner.

Recommendations for the management of patients with systemic rheumatic diseases during the coronavirus disease pandemic

Patients with systemic rheumatic diseases (SRD) are vulnerable for coronavirus disease (COVID-19). The Korean College of Rheumatology recognized the urgent need to develop recommendations for rheumatologists and other physicians to manage patients with SRD during the COVID-19 pandemic. The working group was organized and was responsible for selecting key health questions, searching and reviewing the available literature, and formulating statements. The appropriateness of the statements was evaluated by voting panels using the modified Delphi method. Four general principles and thirteen individual recommendations were finalized through expert consensus based on the available evidence. The recommendations included preventive measures against COVID-19, medicinal treatment for stable or active SRD patients without COVID-19, medicinal treatment for SRD patients with COVID-19, and patient evaluation and monitoring. Medicinal treatments were categorized according to the status with respect to both COVID-19 and SRD. These recommendations should serve as a reference for individualized treatment for patients with SRD. As new evidence is emerging, an immediate update will be required.

What should we prepare for the next coronavirus disease 2019 outbreak? A survey on the opinions of infectious diseases specialists in South Korea

BACKGROUND/AIMS

This study aimed to collect information on the opinions of Korean infectious disease (ID) experts on coronavirus disease 2019 (COVID-19) and related issues in preparation for a future outbreak.

METHODS

A survey was conducted over the course of 5 days (from April 21 to 25, 2020), targeting all adult ID specialists currently in the medical field in South Korea (n = 265). An online-based survey was forwarded via text message and e-mail. Only one response was accepted from each participant.

RESULTS

Of these 265 ID specialists gotten to, 132 (49.8%) responded. The highest proportion of the respondents envisaged the current COVID-19 outbreak to end after December 2020 (47.7% for the domestic Korean outbreak and 70.5% for the global pandemic); moreover, 60.7% of them stated that a second nationwide wave is likely to occur between September and December 2020 in South Korea. N95 respirators were considered to be the most important item in hospitals in preparation for a second wave. The most important policy to be implemented at the national level was securing national hospitals designated for the treatment of ID (67.4%).

CONCLUSION

ID experts in South Korea believe that the COVID-19 pandemic may not be easily controlled and that a second nationwide wave is likely to occur in South Korea. Our results indicate that Korean ID specialists believe that a high level of preparation is needed in various aspects, including the procurement of personal protective equipment, to respond efficiently to a second outbreak.

Are cloth masks a substitute to medical masks in reducing transmission and contamination? A systematic review

During the COVID-19 pandemic the use of cloth masks has increased dramatically due to the shortage of medical masks. However, the efficiency of this material is controversial. We aimed to investigate the efficiency of cloth masks in reducing transmission and contamination by droplets and aerosols for the general population and healthcare workers. Electronic databases were searched without year or language restrictions. Clinical and laboratorial studies were included. The risk of bias (RoB) was assessed using an adapted quality checklist for laboratory-based studies. ROBINS-I tool and Cochrane RoB 2.0 were used to evaluate non-randomized (n-RCT) and randomized clinical trials (RCT), respectively. The quality of the evidence was assessed through GRADE tool. From the eleven studies selected, eight were laboratory-based studies, one non-randomized and one RCT supported by laboratory data. Between the evaluated fabrics only three presented a filtration efficiency > 90%. Hybrid of cotton/chiffon (95%CI 95.2 to 98.8), hybrid of cotton/silk (95%CI 92.2 to 95.8) and cotton quilt (95%CI 94.2 to 97.8). However, cloth masks are not recommended for healthcare workers. A meta-analysis was not feasible due to a high methodological heterogeneity. The overall quality of evidence ranged from very low to moderate. Despite the lower efficiency compared to medical masks, laboratorial results may underestimate the efficiency of cloth masks in real life. Cloth mask efficiency is higher when made of hybrid fabrics (cotton/chiffon, cotton/silk) and cotton quilt, mainly with multiple layers.