Yes that was a prominent theory at one time and helped a lot of the public adopt masks but it is actually both https://www.npr.org/sections/health-shots/2020/11

Yes that was a prominent theory at one time and helped a lot of the public adopt masks but it is actually both https://www.npr.org/sections/health-shots/2020/11/11/933903848/wear-masks-to-protect-yourself-from-the-coronavirus-not-only-others-cdc-stresses https://www.npr.org/sections/health-shots/2020/11/11/9339038...