Wearing face masks in public can reduce the prevalence of the novel coronavirus disease (COVID-19) by reducing the spread of respiratory droplets. An April 22 analysis of mortality rates in 169 countries indicates that wearing face masks may also save lives.
The study, “Country-wide Coronavirus Mortality and Use of Masks by the Public,” found that the per-capita mortality tended to increase by 43% weekly in countries where people were not wearing masks, compared with a 2.8% increase in countries where people were wearing masks. The analysis looked at COVID-19 testing, deaths and mask-wearing practices for the three weeks beginning March 30.
“Our research supports the universal wearing of masks by the public to suppress the spread of the coronavirus,” said co-author Craig McKeown, M.D., professor of clinical ophthalmology at the Bascom Palmer Eye Institute, part of the University of Miami Miller School of Medicine. “Mask-wearing should be adopted immediately, based on the precautionary principle.”
The analysis was submitted to an academic journal as a letter, with Christopher T. Leffler, M.D., M.P.H., associate professor of ophthalmology at Virginia Commonwealth University (VCU) as first author. Co-authors included Dr. McKeown and contributors from VCU, the University of Toronto and the University of Warmia and Mazury in Poland.
“We posted our analysis on researchgate.net, prior to a peer review, because of the urgency of the COVID-19 threat to public health,” Dr. Leffler said. He launched the collaborative research initiative in March, reaching out to former VCU assistant professor Stephen Schwartz, M.D., M.B.A., who is currently professor of clinical ophthalmology and medical director at Bascom Palmer Eye Institute at Naples, who connected him with Dr. McKeown.
On April 5, the researchers posted an initial analysis, “Country-wide Mortality from the Novel Coronavirus (COVID-19) Pandemic and Notes Regarding Mask Usage by the Public.” For example, that comparative analysis found the mortality curve in the Czech Republic had flattened following a mandate for public mask usage on March 19, while COVID-19 deaths continued to rise in Italy and Spain.
“Public health authorities and governments have varied in their policies regarding the use of face masks by the public,” said Dr. Leffler, who noted that the U.S. Centers for Disease Control and Prevention on April 13 issued a recommendation for individuals to wear cloth face masks in public settings.
“Our international analysis indicates that wearing face masks in public can flatten the mortality curve,” Dr. McKeown said. “All of us should wear masks in public, because almost anyone could be unknowingly spreading the virus.”