Are cloth masks as effective as surgical masks at reducing the risk of contracting viruses that cause respiratory disease?

Submitted by: MChoi 148

No. The studies in this list for which we have identified answers are unanimous on this conclusion.
NOTE: New research on COVID-19 comes out nearly every day. The state of our knowledge may change quickly so take this answer with a grain of salt.
This short answer was generated by aggregating the answers that each of the 6 studies below gave to the question (as indicated by State of K members) and adjusting for source quality and other factors. If key studies are missing or the answers attributed to individual studies are incorrect, the above answer could be wrong. For medical questions, don't rely on the information here. Consult a medical professional.


Chart summary of 6 studies examining this question

All answers are assigned by State of K users. The label Couldn't Identify means that State of K was not able to determine whether a study answers the question "yes" or "no". This could be due to several factors. One possibility is that a study found some evidence to indicate that the answer to the question is "yes" and some evidence to indicate that the answer is "no". This often happens when a study uses two or more proxies to study the same phenomenon (i.e. firearm sales figures and self-reported firearm ownership rates as proxies for the prevalence of firearms) and the proxies yield different results when looking for correlations with another phenomenon (i.e. firearm-related deaths). Alternatively, the label may be applied if the phenomenon under study (i.e. whether breast milk improves cognitive function) is true for one group, but not another (i.e. true for girls, but not for boys). Yet another possibility is that a study found there was insufficient evidence to reach a conclusion regarding the question. Finally, the full text or abstract of a study may not have been written clearly or was inaccessible. This would make it difficult to determine how a study answered a question.

All labels of Literature Reviews and source quality are assigned by State of K. For academic journals, the label "Q[NUMBER]" is an indication of the quality of the publication. The "NUMBER" refer to the best quartile in which the journal appeared among all the subjects in which the journal was ranked by Scimago Institutions Rankings. For example, if a journal was ranked in the third quartile (Q3) in infectious diseases, but in the second quartile in Ebola studies (Q2), you would see "Q2". The best quartile is "Q1". Publications other than academic journals may be labeled as "Highly Regarded Sources". Government sources receive this label as do NGOs ranked by the TTCSP Global Go To Think Tank Index Reports. The information contained in a source that is labeled "highly regarded" or "Q1" is not necessarily more accurate than information contained in a source without that label, but these are rough guides to source quality.

Additional Recommended Studies Not in this List (yet)

QUESTIONS TO CONSIDER
Do adults get sick from COVID-19 more often than children?
10 studies
Submitted by: JLjilijana 85

Do cloth masks reduce the risk of contracting viruses that cause respiratory disease?
5 studies
Submitted by: JAloni 111

Does air pollution accelerate the spread of COVID-19?
5 studies
Submitted by: JLjilijana 85

Does air pollution increase the severity of symptoms from COVID-19?
6 studies
Submitted by: KKrista 83

Does an N95 mask reduce the risk of contracting viruses that cause respiratory disease better than a surgical mask?
17 studies
Submitted by: ELee 65

Does a surgical (non-N95) mask reduce the risk of contracting viruses that cause respiratory disease?
23 studies
Submitted by: ELee 65

Add question
What additional question do you want someone who searches for "are cloth masks as effective as surgical masks at reducing the risk of contracting viruses that cause respiratory disease" to consider?

SUMMARIES OF STUDIES
Total studies in list: 6
Sorted by publication year
1
Evaluating the efficacy of cloth facemasks in reducing particulate matter exposure.
"Inexpensive cloth masks are widely used in developing countries to protect from particulate pollution albeit limited data on their efficacy exists. This study examined the efficiency of four types of masks (three types of cloth masks and one type of surgical mask) commonly worn in the developing world. Five monodispersed aerosol sphere size (30, 100, and 500 nm, and 1 and 2.5 μm) and diluted whole diesel exhaust was used to assess facemask performance. Among the three cloth mask types, a cloth mask with an exhaust valve performed best with filtration efficiency of 80-90% for the measured polystyrene latex (PSL) particle sizes. Two styles of commercially available fabric masks were the least effective with a filtration efficiency of 39-65% for PSL particles, and they performed better as the particle size increased. When the cloth masks were tested against lab-generated whole diesel particles, the filtration efficiency for three particle sizes (30, 100, and 500 nm) ranged from 15% to 57%. Standard N95 mask performance was used as a control to compare the results with cloth masks, and our results suggest that cloth masks are only marginally beneficial in protecting individuals from particles<2.5 μm. Compared with cloth masks, disposable surgical masks are more effective in reducing particulate exposure."
AUTHORS
Richard E Peltier
Randa Kallin
Alyssa Noyes
Kabindra M Shakya
PUBLISHED
2017 in Journal of exposure science & environmental epidemiology
High quality source
No
No
2
A cluster randomised trial of cloth masks compared with medical masks in healthcare workers.
"Objective: The aim of this study was to compare the efficacy of cloth masks to medical masks in hospital healthcare workers (HCWs). The null hypothesis is that there is no difference between medical masks and cloth masks.Setting: 14 secondary-level/tertiary-level hospitals in Hanoi, Vietnam.Participants: 1607 hospital HCWs aged ≥18 years working full-time in selected high-risk wards.Intervention: Hospital wards were randomised to: medical masks, cloth masks or a control group (usual practice, which included mask wearing). Participants used the mask on every shift for 4 consecutive weeks.Main Outcome Measure: Clinical respiratory illness (CRI), influenza-like illness (ILI) and laboratory-confirmed respiratory virus infection.Results: The rates of all infection outcomes were highest in the cloth mask arm, with the rate of ILI statistically significantly higher in the cloth mask arm (relative risk (RR)=13.00, 95% CI 1.69 to 100.07) compared with the medical mask arm. Cloth masks also had significantly higher rates of ILI compared with the control arm. An analysis by mask use showed ILI (RR=6.64, 95% CI 1.45 to 28.65) and laboratory-confirmed virus (RR=1.72, 95% CI 1.01 to 2.94) were significantly higher in the cloth masks group compared with the medical masks group. Penetration of cloth masks by particles was almost 97% and medical masks 44%.Conclusions: This study is the first RCT of cloth masks, and the results caution against the use of cloth masks. This is an important finding to inform occupational health and safety. Moisture retention, reuse of cloth masks and poor filtration may result in increased risk of infection. Further research is needed to inform the widespread use of cloth masks globally. However, as a precautionary measure, cloth masks should not be recommended for HCWs, particularly in high-risk situations, and guidelines need to be updated.Trial Registration Number: Australian New Zealand Clinical Trials Registry: ACTRN12610000887077."
AUTHORS
C Raina MacIntyre
Holly Seale
Quanyi Wang
Dominic E Dwyer
Nguyen Tran Hien
Phan Thi Nga et al
PUBLISHED
2015 in BMJ Open
High quality source
No
No
3
Use of cloth masks in the practice of infection control – evidence and policy gaps
"Cloth masks are commonly used in low and middle income countries. It is generally believed that the primarypurpose of cloth masks is to prevent spread of infections from the wearer. However, historical evidence showsthat they have previously been used to protect health care workers (HCWs) from respiratory infections. Currentlythere is a lack of evidence on the efficacy of cloth masks. In this paper, we examined the evidence around theefficacy of cloth masks and discuss the use of cloth masks as a mode of protection from infections in HCWs.We also reviewed the various approaches implemented to try and improve the effectiveness of cloth masks; forexample; type of fabric, masks design and face fit.Our results highlight that there is currently no published research on the efficacy of cloth masks. The fewavailable studies on cloth masks are either descriptive or in-vitro. Studies show that some fabrics may providebetter protection than others, and that in-vitro filtration capacity improves with increasing fineness of fabricand number of layers. The presence of moisture, distance traveled by the droplets and the design of mask wereidentified as other important factors related to the in-vitro filtration efficacy. Cloth masks may provide someprotection and reduce exposure to respiratory aerosols, but this is unproven in the absence of a RCT. Giventhat cloth masks are widely used around the world and are not adequately addressed in infection controlguidelines, research is required to test the clinical efficacy of cloth masks. Other future research questionsshould include filtration efficacy, length of use, methods of decontamination and fit testing. The use of clothmasks should be addressed in policy documents to inform best practice in low and middle income countries."
AUTHORS
Chandini Raina MacIntyre
Abrar Ahmad Chughtai
Holly Seale
PUBLISHED
2013 in International Journal of Infection Control
UNRANKED SOURCE
Couldn't Identify
Couldn't Identify
4
Testing the Efficacy of Homemade Masks: Would They Protect in an Influenza Pandemic?
"Objective: This study examined homemade masks as an alternative to commercial face masks.Methods: Several household materials were evaluated for the capacity to block bacterial and viral aerosols. Twenty-one healthy volunteers made their own face masks from cotton t-shirts; the masks were then tested for fit. The number of microorganisms isolated from coughs of healthy volunteers wearing their homemade mask, a surgical mask, or no mask was compared using several air-sampling techniques.Results: The median-fit factor of the homemade masks was one-half that of the surgical masks. Both masks significantly reduced the number of microorganisms expelled by volunteers, although the surgical mask was 3 times more effective in blocking transmission than the homemade mask.Conclusion: Our findings suggest that a homemade mask should only be considered as a last resort to prevent droplet transmission from infected individuals, but it would be better than no protection."
AUTHORS
George Kafatos
Allan Bennett
Anna Davies
Jimmy Walker
Katy-Anne Thompson
Karthika Giri
PUBLISHED
2013 in Disaster Medicine and Public Health Preparedness
Q2
No
No
5
Simple Respiratory Protection—Evaluation of the Filtration Performance of Cloth Masks and Common Fabric Materials Against 20–1000 nm Size Particles
"A shortage of disposable filtering facepiece respirators can be expected during a pandemic respiratory infection such as influenza A. Some individuals may want to use common fabric materials for respiratory protection because of shortage or affordability reasons. To address the filtration performance of common fabric materials against nano-size particles including viruses, five major categories of fabric materials including sweatshirts, T-shirts, towels, scarves, and cloth masks were tested for polydisperse and monodisperse aerosols (20-1000 nm) at two different face velocities (5.5 and 16.5 cm s⁻¹) and compared with the penetration levels for N95 respirator filter media. The results showed that cloth masks and other fabric materials tested in the study had 40-90% instantaneous penetration levels against polydisperse NaCl aerosols employed in the National Institute for Occupational Safety and Health particulate respirator test protocol at 5.5 cm s⁻¹. Similarly, varying levels of penetrations (9-98%) were obtained for different size monodisperse NaCl aerosol particles in the 20-1000 nm range. The penetration levels of these fabric materials against both polydisperse and monodisperse aerosols were much higher than the penetrations for the control N95 respirator filter media. At 16.5 cm s⁻¹ face velocity, monodisperse aerosol penetrations slightly increased, while polydisperse aerosol penetrations showed no significant effect except one fabric mask with an increase. Results obtained in the study show that common fabric materials may provide marginal protection against nanoparticles including those in the size ranges of virus-containing particles in exhaled breath."
PUBLISHED
2010 in The Annals of Occupational Hygiene
UNRANKED SOURCE
No
No
6
Professional and home-made face masks reduce exposure to respiratory infections among the general population.
"Background: Governments are preparing for a potential influenza pandemic. Therefore they need data to assess the possible impact of interventions. Face-masks worn by the general population could be an accessible and affordable intervention, if effective when worn under routine circumstances.Methodology: We assessed transmission reduction potential provided by personal respirators, surgical masks and home-made masks when worn during a variety of activities by healthy volunteers and a simulated patient.Principal Findings: All types of masks reduced aerosol exposure, relatively stable over time, unaffected by duration of wear or type of activity, but with a high degree of individual variation. Personal respirators were more efficient than surgical masks, which were more efficient than home-made masks. Regardless of mask type, children were less well protected. Outward protection (mask wearing by a mechanical head) was less effective than inward protection (mask wearing by healthy volunteers).Conclusions/Significance: Any type of general mask use is likely to decrease viral exposure and infection risk on a population level, in spite of imperfect fit and imperfect adherence, personal respirators providing most protection. Masks worn by patients may not offer as great a degree of protection against aerosol transmission."
AUTHORS
Rob Sabel
Peter Teunis
Marianne van der Sande
PUBLISHED
2008 in PLoS ONE
High quality source
No
No







ADDITIONAL STUDIES TO CONSIDER ADDING TO LIST
Total additional studies: 30
State of K's algorithms generated the list of studies below based on the studies that were added to the above list. Some of these studies may also examine: "Are cloth masks as effective as surgical masks at reducing the risk of contracting viruses that cause respiratory disease?" If a study examines this question, add it to the list by pressing the button.

Only add studies that examine the same question. Do not add studies that are merely on the same topic.

Non-pharmaceutical interventions for the prevention of respiratory tract infections during Hajj pilgrimage
"Overcrowding during the yearly Hajj mass gatherings is associated with increased risk of spreading infectious diseases, particularly respiratory diseases. Non-pharmaceutical interventions (e.g., hand hygiene, wearing face masks, social distancing) are known to reduce the spread of respiratory viruses from person to person and are therefore recommended to pilgrims by public health agencies. The implementation of effective public health policies and recommendations involves evaluating the adherence to and effectiveness of these measures in the specific context of the Hajj. This review summarizes the evidence related to the effectiveness of non-pharmaceutical interventions in preventing the spread of respiratory infectious diseases during the Hajj. Overall, although hand hygiene compliance is high among pilgrims, face mask use and social distancing remain difficult challenges. Data about the effectiveness of these measures at the Hajj are limited, and results are contradictory, highlighting the need for future large-scale studies. "
AUTHORS
Philippe Brouqui
Samir Benkouiten
Philippe Gautret
PUBLISHED
2014 in Travel Medicine and Infectious Disease

Add to List
In search of feasible interventions for the prevention and cure of novel Coronavirus disease 2019
"COVID-19 (coronavirus disease 2019) is a public health emergency of international concern caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). As of this time, there is no known effective pharmaceutical, phytopharmaceutical or traditional medicine for cure or prevention of COVID-19, although it is urgently needed. Based on the current understanding of the disease molecular mechanisms from the closest relatives of SARS-CoV-2 as well as novel Coronavirus SARS-CoV-2, I attempt to translate this knowledge into identifying some naturally occurring plant based substances and Ayurvedic medicinal herbs that could feasibly be used as preventive as well as treatment options for COVID-19."
AUTHOR
Sunil Verma
PUBLISHED
2020 in Center for Open Science

Add to List
Highly regarded source
An Analysis of 38 Pregnant Women with COVID-19, Their Newborn Infants, and Maternal-Fetal Transmission of SARS-CoV-2: Maternal Coronavirus Infections and Pregnancy Outcomes
" The emergence of a novel coronavirus, termed SARS-CoV-2, and the potentially life-threating respiratory disease that it can produce, COVID-19, has rapidly spread across the globe creating a massive public health problem. Previous epidemics of many emerging viral infections have typically resulted in poor obstetrical outcomes including maternal morbidity and mortality, maternal-fetal transmission of the virus, and perinatal infections and death. This communication reviews the effects of two previous coronavirus infections - severe acute respiratory syndrome (SARS) caused by SARS-CoV and Middle East respiratory syndrome (MERS) caused by MERS-CoV - on pregnancy outcomes. In addition, it analyzes literature describing 38 pregnant women with COVID-19 and their newborns in China to assess the effects of SARS-CoV-2 on the mothers and infants including clinical, laboratory and virologic data, and the transmissibility of the virus from mother to fetus. This analysis reveals that unlike coronavirus infections of pregnant women caused by SARS and MERS, in these 38 pregnant women COVID-19 did not lead to maternal deaths. Importantly, and similar to pregnancies with SARS and MERS, there were no confirmed cases of intrauterine transmission of SARS-CoV-2 from mothers with COVID-19 to their fetuses. All neonatal specimens tested, including in some cases placentas, were negative by rt-PCR for SARS-CoV-2. At this point in the global pandemic of COVID-19 infection there is no evidence that SARS-CoV-2 undergoes intrauterine or transplacental transmission from infected pregnant women to their fetuses. Analysis of additional cases is necessary to determine if this remains true. "
AUTHOR
David A. Schwartz
PUBLISHED
2020 in Archives of Pathology & Laboratory Medicine

Add to List
Systematic Comparison of Two Animal-to-Human Transmitted Human Coronaviruses: SARS-CoV-2 and SARS-CoV
"After the outbreak of the severe acute respiratory syndrome (SARS) in the world in 2003, human coronaviruses (HCoVs) have been reported as pathogens that cause severe symptoms in respiratory tract infections. Recently, a new emerged HCoV isolated from the respiratory epithelium of unexplained pneumonia patients in the Wuhan seafood market caused a major disease outbreak and has been named the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This virus causes acute lung symptoms, leading to a condition that has been named as “coronavirus disease 2019” (COVID-19). The emergence of SARS-CoV-2 and of SARS-CoV caused widespread fear and concern and has threatened global health security. There are some similarities and differences in the epidemiology and clinical features between these two viruses and diseases that are caused by these viruses. The goal of this work is to systematically review and compare between SARS-CoV and SARS-CoV-2 in the context of their virus incubation, originations, diagnosis and treatment methods, genomic and proteomic sequences, and pathogenic mechanisms."
AUTHORS
Jiabao Xu
Yunlong Wang
Xiangqian Guo
Wan Zhu
Longxiang Xie
Tieshan Teng et al
PUBLISHED
2020 in Viruses

Add to List
Potent Antiviral Activities of Type I Interferons to SARS-CoV-2 Infection
"The ongoing historic outbreak of COVID-19 not only constitutes a global public health crisis, but also carries a devastating social and economic impact. The disease is caused by a newly identified coronavirus, Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2). There is an urgent need to identify antivirals to curtail the COVID-19 pandemic. Herein, we report the remarkable sensitivity of SARS-CoV-2 to recombinant human interferons α and β (IFNα/β). Treatment with IFN-α at a concentration of 50 international units (IU) per milliliter drastically reduces viral titers by 3.4 log or over 4 log, respectively, in Vero cells. The EC50 of IFN-α and IFN-β treatment is 1.35 IU/ml and 0.76 IU/ml, respectively, in Vero cells. These results suggest that SARS-CoV-2 is more sensitive than many other human pathogenic viruses, including SARS-CoV. Overall, our results demonstrate the potent efficacy of human Type I IFN in suppressing SARS-CoV-2 infection, a finding which could inform future treatment options for COVID-19."
AUTHORS
Cheng Huang
Slobodan Paessler
Junki Maruyama
Natalya Bukreyeva
Emily K. Mantlo
PUBLISHED
2020 in Cold Spring Harbor Laboratory

Add to List
Highly regarded source
COVID-19 Pandemic, Corona Viruses, and Diabetes Mellitus
" The pandemic of COVID-19, a disease caused by a novel coronavirus (CoV), SARS-CoV-2, is causing substantial morbidity and mortality. Older age and presence of diabetes mellitus, hypertension, and obesity significantly increases the risk for hospitalization and death in COVID-19 patients. In this Perspective, informed by the studies on severe acute respiratory syndrome, SARS-CoV, and Middle East respiratory syndrome, MERS-CoV, and the current literature on SARS-CoV-2, we discuss potential mechanisms by which diabetes modulates the host-viral interactions and host-immune responses. We hope to highlight gaps in knowledge that require further studies pertinent to COVID-19 in patients with diabetes. "
AUTHORS
Ranganath Muniyappa
Sriram Gubbi
PUBLISHED
2020 in American Journal of Physiology-Endocrinology and Metabolism

Add to List
Highly regarded source
An Analysis of 38 Pregnant Women with COVID-19, Their Newborn Infants, and Maternal-Fetal Transmission of SARS-CoV-2: Maternal Coronavirus Infections and Pregnancy Outcomes
"The emergence of a novel coronavirus, termed SARS-CoV-2, and the potentially life-threatening respiratory disease that it can produce, COVID-19, has rapidly spread across the globe creating a massive public health problem. Previous epidemics of many emerging viral infections have typically resulted in poor obstetrical outcomes including maternal morbidity and mortality, maternal-fetal transmission of the virus, and perinatal infections and death. This communication reviews the effects of two previous coronavirus infections - severe acute respiratory syndrome (SARS) caused by SARS-CoV and Middle East respiratory syndrome (MERS) caused by MERS-CoV - on pregnancy outcomes. In addition, it analyzes literature describing 38 pregnant women with COVID-19 and their newborns in China to assess the effects of SARS-CoV-2 on the mothers and infants including clinical, laboratory and virologic data, and the transmissibility of the virus from mother to fetus. This analysis reveals that unlike coronavirus infections of pregnant women caused by SARS and MERS, in these 38 pregnant women COVID-19 did not lead to maternal deaths. Importantly, and similar to pregnancies with SARS and MERS, there were no confirmed cases of intrauterine transmission of SARS-CoV-2 from mothers with COVID-19 to their fetuses. All neonatal specimens tested, including in some cases placentas, were negative by rt-PCR for SARS-CoV-2. At this point in the global pandemic of COVID-19 infection there is no evidence that SARS-CoV-2 undergoes intrauterine or transplacental transmission from infected pregnant women to their fetuses. Analysis of additional cases is necessary to determine if this remains true."
AUTHOR
Schwartz DA
PUBLISHED
2020 in Archives of Pathology & Laboratory Medicine

Add to List
Literature review
Highly regarded source
Physical interventions to interrupt or reduce the spread of respiratory viruses: systematic review.
"Objective: To review systematically the evidence of effectiveness of physical interventions to interrupt or reduce the spread of respiratory viruses.

Data Sources: Cochrane Library, Medline, OldMedline, Embase, and CINAHL, without restrictions on language or publication. Data selection Studies of any intervention to prevent the transmission of respiratory viruses (isolation, quarantine, social distancing, barriers, personal protection, and hygiene). A search of study designs included randomised trials, cohort, case-control, crossover, before and after, and time series studies. After scanning of the titles, abstracts and full text articles as a first filter, a standardised form was used to assess the eligibility of the remainder. Risk of bias of randomised studies was assessed for generation of the allocation sequence, allocation concealment, blinding, and follow-up. Non-randomised studies were assessed for the presence of potential confounders and classified as being at low, medium, or high risk of bias.

Data Synthesis: 58 papers of 59 studies were included. The quality of the studies was poor for all four randomised controlled trials and most cluster randomised controlled trials; the observational studies were of mixed quality. Meta-analysis of six case-control studies suggested that physical measures are highly effective in preventing the spread of severe acute respiratory syndrome: handwashing more than 10 times daily (odds ratio 0.45, 95% confidence interval 0.36 to 0.57; number needed to treat=4, 95% confidence interval 3.65 to 5.52), wearing masks (0.32, 0.25 to 0.40; NNT=6, 4.54 to 8.03), wearing N95 masks (0.09, 0.03 to 0.30; NNT=3, 2.37 to 4.06), wearing gloves (0.43, 0.29 to 0.65; NNT=5, 4.15 to 15.41), wearing gowns (0.23, 0.14 to 0.37; NNT=5, 3.37 to 7.12), and handwashing, masks, gloves, and gowns combined (0.09, 0.02 to 0.35; NNT=3, 2.66 to 4.97). The combination was also effective in interrupting the spread of influenza within households. The highest quality cluster randomised trials suggested that spread of respiratory viruses can be prevented by hygienic measures in younger children and within households. Evidence that the more uncomfortable and expensive N95 masks were superior to simple surgical masks was limited, but they caused skin irritation. The incremental effect of adding virucidals or antiseptics to normal handwashing to reduce respiratory disease remains uncertain. Global measures, such as screening at entry ports, were not properly evaluated. Evidence was limited for social distancing being effective, especially if related to risk of exposure-that is, the higher the risk the longer the distancing period.

Conclusion: Routine long term implementation of some of the measures to interrupt or reduce the spread of respiratory viruses might be difficult. However, many simple and low cost interventions reduce the transmission of epidemic respiratory viruses. More resources should be invested into studying which physical interventions are the most effective, flexible, and cost effective means of minimising the impact of acute respiratory tract infections."
AUTHORS
Ghada A Bawazeer
Lubna A Al-Ansary
Eliana Ferroni
Liz Dooley
Chris Del Mar
Tom Jefferson et al
PUBLISHED
2009 in BMJ : British Medical Journal

Add to List
Textile Masks and Surface Covers - A 'Universal Droplet Reduction Model' Against Respiratory Pandemics
"The main form of COVID-19 transmission is via oral-respiratory droplet contamination (droplet; very small drop of liquid) produced when individuals talk, sneeze or cough. In hospitals, health-care workers wear facemasks as a minimum medical droplet precaution to protect themselves. Due to the shortage of masks during the pandemic, priority is given to hospitals for their distribution. As a result, the availability/use of medical masks is discouraged for the public. However, given that asymptomatic individuals, not wearing masks within the public, can be highly contagious for COVID-19, prevention of environmental droplet contamination (EnDC) from coughing/sneezing/speech is fundamental to reducing transmission. As an immediate solution to promote public droplet safety, we assessed household textiles to quantify their potential as effective environmental droplet barriers (EDBs). The synchronized implementation of a universal community droplet reduction solution is discussed as a model against COVID-19. Using a bacterial-suspension spray simulation model of droplet ejection (mimicking a sneeze), we quantified the extent by which widely available clothing fabrics reduce the dispersion of droplets onto surfaces within 1.8m, the minimum distance recommended for COVID-19 social distancing. All textiles reduced the number of droplets reaching surfaces, restricting their dispersion to &lt;30cm, when used as single layers. When used as double-layers, textiles were as effective as medical mask/surgical-cloth materials, reducing droplet dispersion to &lt;10cm, and the area of circumferential contamination to ~0.3%. The synchronized implementation of EDBs as a community droplet reduction solution (i.e., face covers/scarfs/masks &amp; surface covers) could reduce EnDC and the risk of transmitting or acquiring infectious respiratory pathogens, including COVID-19."
AUTHORS
Theresa Pizarro
Fabio Cominelli
Abigail Basson
Sanja Ilic
Alexander Rodriguez-Palacios
PUBLISHED
2020 in Cold Spring Harbor Laboratory

Add to List
Literature review
Physical interventions to interrupt or reduce the spread of respiratory viruses. Part 1 - Face masks, eye protection and person distancing: systematic review and meta-analysis
"Abstract

OBJECTIVE: To examine the effectiveness of eye protection, face masks, or person distancing on
interrupting or reducing the spread of respiratory viruses.

DESIGN: Update of a Cochrane review that included a meta-analysis of observational studies during the SARS outbreak of 2003.

DATA SOURCES: Eligible trials from the previous review; search of Cochrane Central Register of
Controlled Trials, PubMed, Embase and CINAHL from October 2010 up to 1 April 2020; and forward
and backward citation analysis.

DATA SELECTION: Randomised and cluster-randomised trials of people of any age, testing the use of
eye protection, face masks, or person distancing against standard practice, or a similar physical
barrier. Outcomes included any acute respiratory illness and its related consequences.

DATA EXTRACTION AND ANALYSIS: Six authors independently assessed risk of bias using the Cochrane tool and extracted data. We used a generalised inverse variance method for pooling using a random-effects model and reported results with risk ratios and 95% Confidence Intervals (CI).

RESULTS: We included 15 randomised trials investigating the effect of masks (14 trials) in healthcare workers and the general population and of quarantine (1 trial). We found no trials testing eye protection. Compared to no masks there was no reduction of influenza-like illness (ILI) cases (Risk Ratio 0.93, 95%CI 0.83 to 1.05) or influenza (Risk Ratio 0.84, 95%CI 0.61-1.17) for masks in the general population, nor in healthcare workers (Risk Ratio 0.37, 95%CI 0.05 to 2.50). There was no difference between surgical masks and N95 respirators: for ILI (Risk Ratio 0.83, 95%CI 0.63 to 1.08), for influenza (Risk Ratio 1.02, 95%CI 0.73 to 1.43). Harms were poorly reported and limited to discomfort with lower compliance. The only trial testing quarantining workers with household ILI contacts found a reduction in ILI cases, but increased risk of quarantined workers contracting influenza. All trials were conducted during seasonal ILI activity.

CONCLUSIONS: Most included trials had poor design, reporting and sparse events. There was insufficient evidence to provide a recommendation on the use of facial barriers without other measures. We found insufficient evidence for a difference between surgical masks and N95 respirators and limited evidence to support effectiveness of quarantine. Based on observational evidence from the previous SARS epidemic included in the previous version of our Cochrane review we recommend the use of masks combined with other measures."
AUTHORS
Ghada Bawazeer
Lubna A Al Ansari
Elaine Beller
Tom Jefferson
Justin Clark
Mark Jones et al
PUBLISHED
2020 in Cold Spring Harbor Laboratory

Add to List
Masks for prevention of respiratory viruses on the BMT unit: results of a quality initiative
"Respiratory viral infections (RVI) cause significant morbidity and mortality in hospitalized oncology patients. These viruses are easily spread from asymptomatic and/or symptomatic healthcare workers and visitors to immunocompromised patients, and literature review of facemasks for prevention of infection revealed mixed results. The Bone Marrow Transplant (BMT) Quality Assurance (QA) Committee at Mount Sinai began a surgical mask initiative on the BMT unit. The purpose of our initiative was to assess the impact of surgical mask implementation for healthcare workers and visitors on nosocomial RVI in all patients hospitalized on the BMT unit. We hypothesized that implementing surgical masks would reduce the number of hospital-acquired RVI. We performed a retrospective study involving all patients with malignancy hospitalized on the BMT unit for 4 years. During the latter 2 years, all healthcare workers and visitors were required to wear a surgical mask in every patient room on the BMT unit. Primary endpoint was incidence of RVI after implementation of surgical masks. The 2-year incidence of RVI in the pre-mask period was 14 out of a total of 15 001 patient days on the unit vs 2 out of 15 608 patient days after mask implementation. The difference in incidence of RVI within the two time intervals was noted to be statistically significant (P<.05, 2-proportion z-test). Our quality initiative demonstrated that surgical masks are an infection control modality that may provide benefit to oncology/BMT units by decreasing the risk for hospital-acquired RVI."
AUTHORS
Amir Steinberg
Kathleen Edmondson-Martin
Imelda De la Vega-Diaz
Sharon Tindle
Fran Wallach
Kelsey A. Sokol et al
PUBLISHED
2016 in Transplant Infectious Disease

Add to List
[Pandemic influenza: rapid sanitary-hygienic measures for initial containment of diffusion].
"Viral respiratory diseases may be characterized by rapid diffusion in population, that often cause epidemic outbreaks or pandemic. Besides, typical high mutations of involved virus (almost always influenza virus) can reduce the validity of the up to date available vaccine. The achievement of new vaccines can require prolonged period. In addition, the availability and efficacy of antiviral drugs against new viruses should be evaluated before their uses. Influenza virus replication occurs in the epithelial cells of the respiratory system, and viruses, present in contaminated secretions, spread mainly by aerosols generated during sneezing, coughing, and speaking. Direct and indirect contacts with contaminated fomites play a role, in transmission of viral infection, even if they are less relevant than aerosol transmission. In the absence of ready for use vaccines and active drugs, some "non-pharmaceutical" strategies can be considered decisive factors to reduce the diffusion of pandemic influenza. Hand washing and disinfection procedures, isolation of ill persons, different indication for use of surgical masks and respiratory masks have to be carefully considered."
AUTHORS
V Puro
M Vitali
M Clementi
C Protano
A Raitano
M Biondi et al
PUBLISHED
2008 in Annali di igiene : medicina preventiva e di comunita

Add to List
Universal and reusable virus deactivation system for respiratory protection.
"Aerosolized pathogens are a leading cause of respiratory infection and transmission. Currently used protective measures pose potential risk of primary/secondary infection and transmission. Here, we report the development of a universal, reusable virus deactivation system by functionalization of the main fibrous filtration unit of surgical mask with sodium chloride salt. The salt coating on the fiber surface dissolves upon exposure to virus aerosols and recrystallizes during drying, destroying the pathogens. When tested with tightly sealed sides, salt-coated filters showed remarkably higher filtration efficiency than conventional mask filtration layer, and 100% survival rate was observed in mice infected with virus penetrated through salt-coated filters. Viruses captured on salt-coated filters exhibited rapid infectivity loss compared to gradual decrease on bare filters. Salt-coated filters proved highly effective in deactivating influenza viruses regardless of subtypes and following storage in harsh environmental conditions. Our results can be applied in obtaining a broad-spectrum, airborne pathogen prevention device in preparation for epidemic and pandemic of respiratory diseases."
AUTHORS
Hyo-Jick Choi
Ilaria Rubino
Su-Hwa Lee
Fu-Shi Quan
Brendan Koch
PUBLISHED
2017 in Scientific Reports

Add to List
Highly regarded source
Compliance with the Use of Medical and Cloth Masks Among Healthcare Workers in Vietnam
FUNDERS
Australian Research Council
"Background: Masks are often worn in healthcare settings to prevent the spread of infection from healthcare workers (HCWs) to patients. Masks are also used to protect the employee from patient-generated infectious organisms but poor compliance can reduce efficacy. The aim of this study was to examine the factors influencing compliance with the use of medical and cloth masks amongst hospital HCWs.

Methods: HCWs compliance with the use of medical and cloth masks was measured over a 4-week period in a randomized controlled trial in Vietnam. HCWs were instructed to record their daily activities in diary cards. Demographic, clinical, and diary card data were used to determine the predictors of compliance and the relationship of compliance with infection outcomes.

Results: Compliance rates for both medical and cloth masks decreased during the 4 weeks: medical mask use decreased from 77 to 68% (P < 0.001) and cloth masks from 78 to 69% (P < 0.001). The presence of adverse events (adjusted RR 0.90, 95% CI 0.85-0.95), and performing aerosol-generating procedures (adjusted RR 0.78, 95% CI 0.73-0.82) were negatively associated with compliance, while contact with febrile respiratory illness patients was positively associated (adjusted RR 1.14, 95% CI 1.07-1.20). Being compliant with medical or cloth masks use (average use ≥70% of working time) was not associated with clinical respiratory illness, influenza-like illness, and laboratory-confirmed viral infection.

Conclusion: Understanding the factors that affect compliance is important for the occupational health and safety of HCWs. New strategies and tools should be developed to increase compliance of HCWs. The presence of adverse events such as discomfort and breathing problems may be the main reasons for the low compliance with mask use and further studies should be conducted to improve the design/material of masks to improve comfort for the wearer.

"
AUTHORS
Tham Chi Dung
Abrar Ahmad Chughtai
C. Raina MacIntyre
Bayzidur Rahman
Andrew Hayen
Holly Seale
PUBLISHED
2016 in Annals Of Occupational Hygiene

Add to List
A human monoclonal antibody blocking SARS-CoV-2 infection
"AbstractThe emergence of the novel human coronavirus SARS-CoV-2 in Wuhan, China has caused a worldwide epidemic of respiratory disease (COVID-19). Vaccines and targeted therapeutics for treatment of this disease are currently lacking. Here we report a human monoclonal antibody that neutralizes SARS-CoV-2 (and SARS-CoV). This cross-neutralizing antibody targets a communal epitope on these viruses and offers potential for prevention and treatment of COVID-19."
AUTHORS
Dubravka Drabek
Frank J.M. van Kuppeveld
Berend-Jan Bosch
Wentao Li
Chunyan Wang
Bart L. Haagmans et al
PUBLISHED
2020 in Cold Spring Harbor Laboratory

Add to List
Protecting healthcare workers from SARS-CoV-2 infection: practical indications
"The World Health Organization has recently defined the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection a pandemic. The infection, that may cause a potentially very severe respiratory disease, now called coronavirus disease 2019 (COVID-19), has airborne transmission via droplets. The rate of transmission is quite high, higher than common influenza. Healthcare workers are at high risk of contracting the infection particularly when applying respiratory devices such as oxygen cannulas or noninvasive ventilation. The aim of this article is to provide evidence-based recommendations for the correct use of “respiratory devices” in the COVID-19 emergency and protect healthcare workers from contracting the SARS-CoV-2 infection."
AUTHORS
Stefano Nava
Paolo Palange
Lara Pisani
Valentina Leo
Cecilia Cisternino
Martina Ferioli
PUBLISHED
2020 in European Respiratory Review

Add to List
COVID-19 infection: Origin, transmission, and characteristics of human coronaviruses
"The coronavirus disease 19 (COVID-19) is a highly transmittable and pathogenic viral infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which emerged in Wuhan, China and spread around the world. Genomic analysis revealed that SARS-CoV-2 is phylogenetically related to severe acute respiratory syndrome-like (SARS-like) bat viruses, therefore bats could be the possible primary reservoir. The intermediate source of origin and transfer to humans is not known, however, the rapid human to human transfer has been confirmed widely. There is no clinically approved antiviral drug or vaccine available to be used against COVID-19. However, few broad-spectrum antiviral drugs have been evaluated against COVID-19 in clinical trials, resulted in clinical recovery. In the current review, we summarize and comparatively analyze the emergence and pathogenicity of COVID-19 infection and previous human coronaviruses severe acute respiratory syndrome coronavirus (SARS-CoV) and middle east respiratory syndrome coronavirus (MERS-CoV). We also discuss the approaches for developing effective vaccines and therapeutic combinations to cope with this viral outbreak."
AUTHORS
Nadia Bashir
Muhammad Adnan Shereen
Abeer Kazmi
Rabeea Siddique
Suliman Khan
PUBLISHED
2020 in Journal of Advanced Research

Add to List
Human monoclonal antibodies block the binding of SARS-CoV-2 spike protein to angiotensin converting enzyme 2 receptor
"The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic of novel corona virus disease (COVID-19). To date, no prophylactic vaccines or approved therapeutic agents are available for preventing and treating this highly transmittable disease. Here we report two monoclonal antibodies (mAbs) cloned from memory B cells of patients recently recovered from COVID-19, and both mAbs specifically bind to the spike (S) protein of SARS-CoV-2, block the binding of receptor binding domain (RBD) of SARS-CoV-2 to human angiotensin converting enzyme 2 (hACE2), and effectively neutralize S protein-pseudotyped virus infection. These human mAbs hold the promise for the prevention and treatment of the ongoing pandemic of COVID-19."
AUTHORS
Lilin Ye
Zhirong Li
Jianfang Tang
Xiangyu Chen
Zhaohui Qian
Yang Yang et al
PUBLISHED
2020 in Cold Spring Harbor Laboratory

Add to List
Literature review
COVID-19 Drug Discovery Using Intensive Approaches
FUNDERS
Japan Agency for Medical Research and Development , Japan Society for the Promotion of Science London , Princess Takamatsu Cancer Research Fund
"Since the infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was reported in China during December 2019, the coronavirus disease 2019 (COVID-19) has spread on a global scale, causing the World Health Organization (WHO) to issue a warning. While novel vaccines and drugs that target SARS-CoV-2 are under development, this review provides information on therapeutics which are under clinical trials or are proposed to antagonize SARS-CoV-2. Based on the information gained from the responses to other RNA coronaviruses, including the strains that cause severe acute respiratory syndrome (SARS)-coronaviruses and Middle East respiratory syndrome (MERS), drug repurposing might be a viable strategy. Since several antiviral therapies can inhibit viral replication cycles or relieve symptoms, mechanisms unique to RNA viruses will be important for the clinical development of antivirals against SARS-CoV-2. Given that several currently marketed drugs may be efficient therapeutic agents for severe COVID-19 cases, they may be beneficial for future viral pandemics and other infections caused by RNA viruses when standard treatments are unavailable."
AUTHORS
Takaaki Hirotsu
Toru Kitagawa
Andrea Vecchione
Ayumu Asai
Masamitsu Konno
Hidetoshi Eguchi et al
PUBLISHED
2020 in International Journal of Molecular Sciences

Add to List
Sitagliptin: a potential drug for the treatment of SARS-CoV-2?
"Recently, an outbreak of fatal coronavirus, SARS-CoV-2, has emerged from China and is rapidly spreading worldwide. As the coronavirus pandemic rages, drug discovery and development become even more challenging. Drug repurposing of the antimalarial drug chloroquine and its hydroxylated form had demonstrated apparent effectiveness in the treatment of COVID-19 associated pneumonia in clinical trials. SARS-CoV-2 spike protein shares 31.9% sequence identity with the spike protein presents in the Middle East Respiratory Syndrome Corona Virus (MERS-CoV), which infects cells through the interaction of its spike protein with the DPP4 receptor found on macrophages. Sitagliptin, a DPP4 inhibitor, that is known for its antidiabetic, immunoregulatory, anti-inflammatory, and beneficial cardiometabolic effects has been shown to reverse macrophage responses in MERS-CoV infection and reduce CXCL10 chemokine production in AIDS patients. We suggest that Sitagliptin may be beneficial alternative for the treatment of COVID-19 disease especially in diabetic patients and patients with preexisting cardiovascular conditions who are already at higher risk of COVID-19 infection."
AUTHOR
Sanaa Bardaweel
PUBLISHED
2020 in Center for Open Science

Add to List
Sitagliptin: a potential drug for the treatment of SARS-CoV-2?
"Recently, an outbreak of fatal coronavirus, SARS-CoV-2, has emerged from China and is rapidly spreading worldwide. As the coronavirus pandemic rages, drug discovery and development become even more challenging. Drug repurposing of the antimalarial drug chloroquine and its hydroxylated form had demonstrated apparent effectiveness in the treatment of COVID-19 associated pneumonia in clinical trials. SARS-CoV-2 spike protein shares 31.9% sequence identity with the spike protein presents in the Middle East Respiratory Syndrome Corona Virus (MERS-CoV), which infects cells through the interaction of its spike protein with the DPP4 receptor found on macrophages. Sitagliptin, a DPP4 inhibitor, that is known for its antidiabetic, immunoregulatory, anti-inflammatory, and beneficial cardiometabolic effects has been shown to reverse macrophage responses in MERS-CoV infection and reduce CXCL10 chemokine production in AIDS patients. We suggest that Sitagliptin may be beneficial alternative for the treatment of COVID-19 disease especially in diabetic patients and patients with preexisting cardiovascular conditions who are already at higher risk of COVID-19 infection."
AUTHOR
Sanaa Bardaweel
PUBLISHED
2020 in Center for Open Science

Add to List
Targeting the Endocytic Pathway and Autophagy Process as a Novel Therapeutic Strategy in COVID-19
"Coronaviruses (CoVs) are a group of enveloped, single-stranded positive genomic RNA viruses and some of them are known to cause severe respiratory diseases in human, including Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome (MERS) and the ongoing coronavirus disease-19 (COVID-19). One key element in viral infection is the process of viral entry into the host cells. In the last two decades, there is increasing understanding on the importance of the endocytic pathway and the autophagy process in viral entry and replication. As a result, the endocytic pathway including endosome and lysosome has become important targets for development of therapeutic strategies in combating diseases caused by CoVs. In this mini-review, we will focus on the importance of the endocytic pathway as well as the autophagy process in viral infection of several pathogenic CoVs inclusive of SARS-CoV, MERS-CoV and the new CoV named as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and discuss the development of therapeutic agents by targeting these processes. Such knowledge will provide important clues for control of the ongoing epidemic of SARS-CoV-2 infection and treatment of COVID-19."
AUTHORS
Han-Ming Shen
Naidi Yang
PUBLISHED
2020 in International Journal of Biological Sciences

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

Add to List
Literature review
Novel Coronavirus: Current Understanding of Clinical Features, Diagnosis, Pathogenesis, and Treatment Options
FUNDERS
American University of Sharjah
"Since December 2019, coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in devastating consequences worldwide and infected more than 350,000 individuals and killed more than 16,000 people. SARS-CoV-2 is the seventh member of the coronavirus family to affect humans. Symptoms of COVID-19 include fever (88%), cough (68%), vomiting (5%) and diarrhoea (3.7%), and transmission of SARS-CoV-2 is thought to occur from human to human via respiratory secretions released by the infected individuals when coughing and sneezing. COVID-19 can be detected through computed tomography scans and confirmed through molecular diagnostics tools such as polymerase chain reaction. Currently, there are no effective treatments against SARS-CoV-2, hence antiviral drugs have been used to reduce the development of respiratory complications by reducing viral load. The purpose of this review is to provide a comprehensive update on the pathogenesis, clinical aspects, diagnosis, challenges and treatment of SARS-CoV-2 infections."
AUTHORS
Naveed Ahmed Khan
Mohammad Ridwane Mungroo
Ruqaiyyah Siddiqui
PUBLISHED
2020 in Pathogens

Add to List
Performance of materials used for biological personal protective equipment against blood splash penetration.
"For occupational safety, healthcare workers must select and wear appropriate personal protective equipment (PPE), protective clothing, and masks as countermeasures against exposure to infectious body fluids and blood splash. It is important for healthcare workers to ensure the protective performance of each PPE against penetration of pathogens. The International Standards Organization (ISO) 22609 test evaluates the effectiveness of medical facemasks to protect against penetration of splashed synthetic blood. However, in this method, the protective performance is determined only visually, without quantification of leaked liquid volume. Therefore, in this study, we modified the ISO 22609 test method to quantify the volume of leaked liquid and obtain a more accurate assessment of the protection performance. We tested non-woven and woven materials used for masks or protective clothing, and the performance of each material was classified using this new method. We found that the quantity of leaked synthetic blood was dependent on the structural characteristics of each material. These findings will allow healthcare workers to select the most appropriate PPE for a given situation or task."
AUTHORS
Hideki Morikawa
Katsuaki Shinohara
Noriko Shimasaki
PUBLISHED
2017 in Industrial Health

Add to List
The effects of two kinds of mask (with or without exhaust valve) on clothing microclimates inside the mask in participants wearing protective clothing for spraying pesticides.
"Aim: The study aimed at discovering the effects of wearing two types of protective mask on the clothing microclimate (temperature, humidity) inside the mask, physiological parameters and subjective sensations.

Method: Five healthy female students performed intermittent step exercise while wearing the protective clothing in a climate chamber at 28 degrees C and 60% relative humidity (RH). One mask was made of non-woven fabric and had no exhaust valve (mask A), and the other had an exhaust valve (mask B).

Results: (1) Clothing microclimate temperature inside the mask was significantly lower in mask B than in mask A. The final values were 35.5 +/- 0.3 degrees C in mask A and 34.6 +/- 0.8 degrees C in mask B. (2) Clothing microclimate humidity inside the mask was significantly lower in mask B than in mask A. The final values were 37.9 +/- 0.9 g/m3 in mask A and 35.7 +/- 2.0 g/m3 in mask B. (3) Cheek skin temperature inside the mask was kept significantly lower in mask B than in mask A. (4) Clothing microclimate humidity at trunk level increased more slowly with mask B than with mask A for four participants. (5) Rectal temperature increased more slowly with mask B than with mask A for three participants. (6) Tympanic temperature increased more slowly with mask B than with mask A for two out of four participants.

Discussion: We discussed these findings from the viewpoint that the dry and wet heat loss was accelerated through the nose under the influence of a reduced level of clothing microclimate inside mask B, having probably helped selective brain cooling by cooling more effectively the vein circulating blood through the nose.

"
AUTHORS
C Hayashi
H Tokura
PUBLISHED
2004 in International Archives of Occupational and Environmental Health

Add to List
Common Materials for Emergency Respiratory Protection: Leakage Tests with a Manikin
"In areas where respirators are not routinely used, emergencies (such as fires) may occur in which protection from airborne particles is necessary. The following readily available materials were tested on a manikin connected to a breathing simulator to determine the fraction of an approximately 2-micron diameter aerosol that would leak around the seal between the materials and the manikin's face: cotton/polyester shirt material, cotton handkerchief material, toweling (a wash cloth), a surgical mask (Johnson & Johnson Co., Model HRI 8137), and a NIOSH-approved disposable face mask (3M Corp., Model #8710). The leakage tests were done to supplement the measurements of penetration through the materials reported previously. Leakage fractions were determined by comparing the penetration of the same aerosol for the materials held to the face versus being fully taped to the face. At a breathing rate of 37 liters per minute, mean leakages for the materials ranged from 0.0 percent to 63 percent, depending on the material. Mean penetrations exclusive of leakage ranged from 0.6 percent to 39 percent. Use of nylon hosiery material ("panty hose") to hold the handkerchief material or the disposable face mask to the face was found to be very effective in preventing leakage. Such a combination could be expected to reduce leakage around the handkerchief to about 10 percent or less in practice, and around the mask to less than one percent, which suggests the adaptation and use of such an approach for industrial hygiene."
AUTHORS
WILLIAM C. HINDS
JOHN M. PRICE
DOUGLAS W. COOPER
HOWELL S. YEE
ROBERT WEKER
PUBLISHED
1983 in American Industrial Hygiene Association Journal

Add to List
Energy cost of wearing chemical protective clothing during progressive treadmill walking.
"While chemical protective (CP) clothing is known to adversely affect physical performance, few data exist regarding the physiological response of wearing US military CP clothing during incremental, dynamic exercise. To quantify the effects of CP clothing on energy cost and to test the hypothesis that the mask contributes little to this effect, oxygen uptake (VO2) and ventilation (VE) were determined in 14 male soldiers who walked on a treadmill at 1.56 m.s-1 for 20 min each at 0, 5, and 10% grades in three clothing conditions: BDU (battledress uniform only), MASK (BDU + M-17 protective mask), and CP clothing (MASK + overgarment, gloves and boots). In BDU's, exercise intensities expressed as %VO2max were 29, 42, and 59% at the three grades, respectively. VO2 was significantly (p < 0.01) greater at all grades (range 13 to 18%) in CP clothing compared to BDU. However, no differences in VO2 were seen between BDU and MASK at any level of exercise. VE was significantly higher at the two highest grades in CP clothing compared to BDU but when expressed relative to VO2 (VE/VO2) was significantly lower at 0% and 5% grades but not at 10%. In the MASK condition, VE was significantly lower at the 10% grade and VE/VO2 was significantly lower at all grades compared to BDU. The results show that despite the mask induced hypoventilation, VO2 is unaffected at exercise intensities up to 60% of VO2max.(ABSTRACT TRUNCATED AT 250 WORDS)"
AUTHORS
J F Patton
M M Murphy
M E Harp
T E Bidwell
R P Mello
PUBLISHED
1995 in Aviation, Space, and Environmental Medicine

Add to List
Forces Required for a Knife to Penetrate a Variety of Clothing Types
"In stabbing incidents, it is usual for the victim to be clothed and therefore a knife penetrates both clothes and skin. Clothes (other than leather) have been thought to make little difference to the penetration force. However, there is little quantitative data in the literature. In this study, a range of clothes have been tested, either singly or in layers of, for example, T-shirt and shirt, to quantify the additional force required when clothes are present. A materials testing system has been used to test the penetration force required to stab through clothes into a foam-silicone rubber skin simulant. The results show that the force required can be significantly different, particularly when layers of clothing are penetrated. A cotton t-shirt adds c. 8 N to the penetration force, while a T-shirt and jacket can add an additional 21 N. The results allow a more quantitative assessment of forces required in stabbing. "
AUTHORS
Guy N. Rutty
Sarah V. Hainsworth
Gary Nolan
PUBLISHED
2012 in Journal of Forensic Sciences

Add to List
Evaluation of Nano- and Submicron Particle Penetration through Ten Nonwoven Fabrics Using a Wind-Driven Approach
"Existing face mask and respirator test methods draw particles through materials under vacuum to measure particle penetration. However, these filtration-based methods may not simulate conditions under which protective clothing operates in the workplace, where airborne particles are primarily driven by wind and other factors instead of being limited to a downstream vacuum. This study was focused on the design and characterization of a method simulating typical wind-driven conditions for evaluating the performance of materials used in the construction of protective clothing. Ten nonwoven fabrics were selected, and physical properties including fiber diameter, fabric thickness, air permeability, porosity, pore volume, and pore size were determined. Each fabric was sealed flat across the wide opening of a cone-shaped penetration cell that was then housed in a recirculation aerosol wind tunnel. The flow rate naturally driven by wind through the fabric was measured, and the sampling flow rate of the Scanning Mobility Particle Sizer used to measure the downstream particle size distribution and concentrations was then adjusted to minimize filtration effects. Particle penetration levels were measured under different face velocities by the wind-driven method and compared with a filtration-based method using the TSI 3160 automated filter tester. The experimental results show that particle penetration increased with increasing face velocity, and penetration also increased with increasing particle size up to about 300 to 500 nm. Penetrations measured by the wind-driven method were lower than those obtained with the filtration method for most of the fabrics selected, and the relative penetration performances of the fabrics were very different due to the vastly different pore structures."
AUTHORS
Bhupender Gupta
Pengfei Gao
Mengshi Yang
Ronald Shaffer
Adam Miller
Peter A. Jaques et al
PUBLISHED
2011 in Journal of Occupational and Environmental Hygiene

Add to List

QUESTIONS TO CONSIDER
Do adults get sick from COVID-19 more often than children?
10 studies
Submitted by: JLjilijana 85

Do cloth masks reduce the risk of contracting viruses that cause respiratory disease?
5 studies
Submitted by: JAloni 111

Does air pollution accelerate the spread of COVID-19?
5 studies
Submitted by: JLjilijana 85

Does air pollution increase the severity of symptoms from COVID-19?
6 studies
Submitted by: KKrista 83

Does an N95 mask reduce the risk of contracting viruses that cause respiratory disease better than a surgical mask?
17 studies
Submitted by: ELee 65

Does a surgical (non-N95) mask reduce the risk of contracting viruses that cause respiratory disease?
23 studies
Submitted by: ELee 65

Add question
What additional question do you want someone who searches for "are cloth masks as effective as surgical masks at reducing the risk of contracting viruses that cause respiratory disease" to consider?