A newly released study in the academic journal Annals of Internal Medicine casts more doubt on policies that force healthy individuals to wear face coverings.
To conduct the study, which ran from early April to early June, scientists at the University of Copenhagen recruited more than 6,000 participants who had tested negative for COVID-19 immediately prior to the experiment.
Half the participants were given surgical masks and instructed to wear them outside the home; the other half were instructed to not wear a mask outside the home.
Roughly 4,860 participants finished the experiment. 42 people in the mask group, or 1.8 percent, got infected, compared with 53 in the unmasked group, or 2.1 percent, a difference not regarded as statistically significant.
Dr. Henning Bundgaard, lead author of the experiment and a physician at the University of Copenhagen, told media. “Our study gives an indication of how much you gain from wearing a mask,” Bundgaard said. “Not a lot.”
The study’s findings are at odds with the Centers for Disease Control and Prevention (CDC), which just last week (November 11) endorsed the view that face coverings protect individuals from contracting the virus.
The results of the Danish study undermine the assertion from public health officials that wearing a surgical mask can protect individuals from COVID-19 infection, but that’s unlikely to end the mask debate, which has become one of the most vitriolic issues in America today.
As for the quality of the study. As reported by Leah Rosenbaum in Forbes.
Dr. Christine Laine, an internal medicine physician and Editor-in-Chief of Annals of Internal Medicine, says that the study did a good job of answering a very specific question: whether or not face masks protect wearers from SARS-CoV-2 infection in areas with low infection rates and high levels of social distancing. “It did not answer the question about whether widespread masking mitigates SARS-CoV-2 infection,” she says, adding that while there were concerns over misinterpretation, the editors agreed publishing this study was important because it is “the only randomized control trial of masks for SARS-CoV-2 infection that has been done to date…this was an important, well-designed study.”
Sources.
- New York Times. https://www.nytimes.com/2020/11/18/health/coronavirus-masks-denmark.html
- According to Wikipedia Annals of Internal Medicine has been published since 1922 and is highly regarded. https://en.wikipedia.org/wiki/Annals_of_Internal_Medicine
- FEE. New Danish Study Finds Masks Don’t Protect Wearers From COVID Infection – Foundation for Economic Education (fee.org)