Face masks protect the person wearing them, leading to less severe disease if exposure does occur, infectious disease experts say.

Investigators reviewed research on COVID-19 outbreaks in healthcare and other communal settings as well as animal studies of disease transmission. The data suggest that various masks, regardless of total protection level, will all block at least some SARS-CoV-2, the virus that causes COVID-19, they reported. 

Exposure to fewer virus particles can lead to milder disease, argued lead researcher Monica Gandhi, M.D. This indicates that masks not only protect the people nearby, but safeguard the user as well, she proposed. This “will allow for the preservation of life and less severe illness, along with other COVID-19 control measures, as society re-opens,” Gandhi and her colleagues wrote.

It also is possible that mask wearing can stave off the most severe infections while allowing just enough disease exposure to provide immunity, added Gandhi, from the University of California, San Francisco.

“Exposing society to SARS-CoV-2 without the unacceptable consequences of severe illness with public masking could lead to greater community-level immunity and slower spread as we await a vaccine,” she concluded.

The study is an article in press, to be published in the August issue of the Journal of General Internal Medicine.