inoculum - a substance (a virus or toxin or immune serum) that is introduced into the body to produce or increase immunity to a particular disease The idea is

inoculum - a substance (a virus or toxin or immune serum) that is introduced into the body to produce or increase immunity to a particular disease The idea is w/o the mask, inoculum dose probably puts the D in COVID. With the mask, you might get SARS-CoV-2–specific T-cell immunity without getting COVID.