11/18/2020
Beaumont study shows how well masks work at stopping COVID-19 virus transmission
Kristen Jordan Shamus
Detroit Free Press
Wearing a mask protects people from contracting the novel coronavirus, according to a new study by the Beaumont Research Institute of employees, which was published earlier this month in Clinical Infectious Diseases.
The study showed that of the 20,614 Beaumont health care workers who took part in the research, 1,818 — or 8.8% — had developed SARS-CoV-2 antibodies on serology blood tests.
That means 91.2% did not contract the virus despite working in health care-related jobs through the first COVID-19 surge in Michigan, when more than 1,200 COVID-19 inpatients were admitted in the health system's eight hospitals.
Among those who reported known direct exposure to a COVID-19-virus positive person, those wearing an N95 mask had a significantly lower rate of developing antibodies (10.2%) compared with workers who wore surgical masks or other masks (13.1%) or no mask at all (17.5%).
And for those who did wear masks, but still got infected with the virus, nearly 30% were asymptomatic. Of the workers who contracted the virus while wearing N95 masks, 40% were asymptomatic. The blood tests were conducted April 13-May 28.
“It’s nice to have proof masking really works,” said Dr. Matthew Sims, director of Infectious Diseases Research at Beaumont Health and lead author of the research paper. “Masks play a vital role in protecting people and can dramatically reduce the risk of contracting COVID-19.”