Is one-way masking enough?: CMAJ

ABSTRACT

Face masks work best to prevent the spread of SARS-CoV-2 when everyone wears one. But experts say it is still worth wearing a mask to protect yourself, even if no one else does. While public health messaging has tended to emphasize the importance of wearing a mask to protect others, numerous studies have demonstrated that the right mask protects the wearer, too. Recent data from the US shows that people who always wore a face mask in indoor public settings were less likely to test positive for SARS-CoV-2 than those who never wore a mask. Better quality masks offered greater protection. Wearing an N95 or KN95 respirator lowered the odds of infection by 83%, whereas wearing a surgical mask or cloth mask lowered the odds by 66% and 56%, respectively.