21.
A March 2021 study looked at the impact of New York City’s April 2020 executive order mandating mask wearing for all in public. At that time, NYC was the epicenter of infections in the U.S., the study published in
Journal of Urban Health explains. Results showed that NYC’s mask mandate prevented 99,517 infections and 7,978 COVID-19 deaths. Additionally, researchers say if the order had been implemented just one week earlier than that, 111,475 infections and 9,017 deaths would have been prevented.
22.
This
Hong Kong study published in The International Journal of Tuberculosis and Lung Disease laments the lack of support for masking in Western countries, as many Asian countries accept and have normalized mask wearing for decades. The researchers point to a previous study cited to dispute benefits of face masks — particularly cloth masks — because they’re considered far less effective than surgical masks. The authors argue that while cloth masks are less effective than surgical masks, the difference is about 70% versus 90%, which they say is still a “very meaningful benefit.”
23.
Authors of a December 2020 study published in
Future Microbiology felt strongly about their findings on mask fit, which found they significantly reduce particle transmission when worn properly. They write:
“Quantitative analysis of the most efficient and effective face masks (in terms of both fit and fabric) will undoubtedly help to stem the spread of not just SAR-CoV-2 but also any illness spread through respiratory particles.”24.
Researchers in this study of efficacy of different materials used for homemade masks found, as expected, different materials have different capabilities in preventing transmission. The laboratory study was performed in
West China Hospital of Sichuan University in Chengdu, China and published in October 2020 by the PLOS One scientific journal community. The lab tested various materials and layering for filtration. The study found that while homemade masks did not meet surgical mask standards, the filtration efficiency and pressure difference inside did. They write:
“…homemade masks using available materials, based on the results of this study, can minimize the chance of infection to the maximum extent.”25.
This
BMJ-published study from New South Wales, Australia, used simulation scenarios to deduce that when used together, masking, high community testing and contact tracing are effective at controlling COVID-19 transmission. The researchers predictions and models lined up pretty closely with how case numbers played out in New South Wales.
26.
Mathematical models were generated based on huge swaths of data for this study published in
Nature Communications. These models found: 1) Even limited distribution of masks offering only 25% protection and containment would result in significant drop in death rates, 2) Even if only 10% of people used the masks offering 25% protection, the death rate would drop 5%, 3) If people used homemade masks that offered even 5% protection and containment, death rates would drop from 2.5 to 2.26 percentage points. Places requiring public masking could also expect a 3-5% reduction in deaths, researchers write.
27.
In this study published in the
European Respiratory Journal, researchers examined information from several countries to determine the differences in spread among those who masked and those who largely didn’t. They urge lawmakers and residents to heed mask guidelines, as it’s a favorable alternative to shutdowns and prolonged social distancing. The authors write:
“… We strongly support the use of cloth masks as a simple, economic and sustainable alternative to surgical masks as a means of source control for general community use, so that disposable surgical masks and N95 respirators can be reserved for use in healthcare facilities.” 28.
A September 2020 study published by the
Association for Psychological Science reviewed several previous studies to determine why many people refuse or resist doing so when, they believe, face masks and social distancing have been proven to help slow disease spread. Researchers of the study, which centered on empathy, reviewed many previous studies to come to the
what before examining the
why.
29.
Using data from 15 previous studies, researchers in this
The Lancet-published study write:
“This study supports universal face mask use, because masks were equally effective in both health-care and community settings when adjusted for type of mask use.” While the authors acknowledge that surgical and N95 masks are more effective than cloth masks, data indicate universal mask wearing can reduce the rate of infection, even with moderately effective ones. Additionally, researchers cite data showing mask wearing in Beijing homes prevented secondary transmission, if worn before symptoms appear.
30.
The Beijing study cited in #38 was published in May 2020 by
BMJ Global Health — it followed 335 people in 124 families that had at least one family member with a confirmed COVID-19 case. Authors found that after nearly a month in the same household, face mask use by all parties before symptom development was 79% effective in transmission reduction.
31.
This study published in the
Emerging Infectious Diseases medical journal concluded that while cloth masks are inferior to surgical masks and shouldn’t be used by healthcare workers, they are a suitable option for community use. Fit and material are key, researchers write, indicating that fabrics with high thread count and fine weave should be used — in addition to several layers of the material.
32.
These
New York University Abu Dhabi researchers examined the resistance of mask wearing in Spain during the early stages of the pandemic. Here, while exploring how attitudes and biases affect decisions to wear masks, explain that many still resist
“despite growing evidence of the effectiveness of face mask use against transmission of respiratory viruses.” Based on their research, the authors urged governments to create programs to improve mask-wearing compliance
33.
A Vietnamese study published in the
Journal of Community Health this year took a look at mask use among university students. Researchers noted Vietnam’s strict mitigation policies during the pandemic, especially given its proximity to China, helped keep case numbers low (about 28 cases per 10 million people). Measures including mandatory masking in public places — and a monetary fine of about $13 US — led to the successful containment of the coronavirus, researchers write. Again, while surgical masking is the preferred method, researchers urge mask use and community education on their importance.
34.
This January 2021 study published in
Journal of Econometrics used robust models, experiments and data sets to review how further masking during the pandemic’s onset may have prevented infections and deaths. They conclude that their analysis “robustly indicates” face mask mandates have reduced the spread of COVID-19. They explain that if all U.S. states had implemented mandatory masking policies on March 14, 2020, the cumulative death toll by the end of May would have been about 19% to 45% smaller — or about 19,000 to 47,000 saved lives.
35.
Just last month, research published on scholarly site
PLOS One examined the “substantial” decline in new COVID-19 cases when mask mandates began amid a surge in Melbourne, Australia. Using models and logarithm data analysis, it’s estimated that mask usage in public spaces rose from around 43% to 97% — resulting in a plunge in virus reproduction and new cases. The authors say they strongly support mask usage in communities.
36.
“Of Masks and Methods,” published in March in
Annals of Internal Medicine, explored how the way masks are worn and implemented affect how effective they are. Researchers examined observational studies and other experiments to conclude that community mask use, especially if widespread, correlates to reduced risk for COVID-19. They write:
“Across all analyses odds ratios were approximately 0.8, consistent with a 20% reduction in incident SARS-CoV-2 infection if masks are recommended… Multiple observational studies have documented an association between mask mandates and reduced COVID-19 incidence.” 37.
This Irish study appearing in scientific journal publisher
MDPI observed the transmission of particles through various mask materials to determine filtration, how porous they were and how much they resist airflow (among other factors). Using mathematical models, statistical data and historical data, they found masks to be an overall effective and necessary tool for the foreseeable future. They explain that as advancements in material occur — including many existing antimicrobial fabrics — masks will prove even more effective. They write:
“Current materials used in production including non-woven fibrous substances have been in use since the beginning of the 20th century and have been shown to be still sufficiently viable in their use.” 38.
A February 2021 study from Ethiopia and published in
Risk Management and Healthcare Policy medical journal combed through databases and other COVID-19 writings to conclude that universal face mask use can contribute to community containment if properly used and available as needed.
39.
This February 2021
JAMA-published study examined several other studies and created a table of different populations around the globe and how their masking use affected spread. They found:
“When masks are worn and combined with other recommended mitigation measures, they protect not only the wearer but also the greater community.” Further, they explain that as mutations emerge, masking will be even more important.
40.
Echoing other findings, the doctor/researcher behind this December 2020
Wisconsin Medical Journal review used over 88 scholarly references to aggregate his ultimate conclusion that the bulk of mask wearing works to control community spread. The author notes that while a mask can only protect wearers from infection to a certain extent, they can help control the viral load they’re exposed to and thus, the severity of their infection.
41.
This May 2021
Medical Decision Making analysis used models to test the ability of masks to slow the spread of COVID-19 during an initial outbreak and an insurgence. The authors used over 50 sources to determine that even with moderately effective masking
“it is evident that mask effectiveness significantly affects transmission.” The researchers recommend masking until at least widespread vaccination occurs.
