> Masks don’t keep you from getting COVID. They only help prevent you from spreading it. ??? Most masks don't have a one-way valve that only filters your exha

> Masks don’t keep you from getting COVID. They only help prevent you from spreading it. ??? Most masks don't have a one-way valve that only filters your exhalation, leaving inhaled air unfiltered. Any given mask is going to be roughly as good at filtering incoming air as it is at filtering outgoing air.