Can a Mask Make You Immune to Covid?

Scientists explore an old treatment while we wait for a vaccine

Nurse vaccinates woman against smallpox, diphtheria, and typhoid. (Library of Congress, Public Domain).

In a recent article, published in the New England Journal of Medicine, researchers Monica Ghandi and George Rutherford proposed that wearing a face mask might stimulate an immune response to the Covid-19 virus. The benefits of wearing a face mask are widely acknowledged. The protective barrier…