A virus is so small, it sails right through cloth masks, not to mention around the sides of masks, not to mention into your eyes. The only good a mask can do, if you are highly symptomatic, is to stop your own cootie boogies from flying out of your face onto other people. Which is why sick people should stay home.
Here is the straight skinny, from an article first published last month, that is miraculously still available online. Thank you, Michael Klompas, M.D., M.P.H., Charles A. Morris, M.D., M.P.H., Julia Sinclair, M.B.A., Madelyn Pearson, D.N.P., R.N., and Erica S. Shenoy, M.D., Ph.D.
“We know that wearing a mask outside health care facilities offers little, if any, protection from infection. Public health authorities define a significant exposure to Covid-19 as face-to-face contact within 6 feet with a patient with symptomatic Covid-19 that is sustained for at least a few minutes (and some say more than 10 minutes or even 30 minutes). The chance of catching Covid-19 from a passing interaction in a public space is therefore minimal. In many cases, the desire for widespread masking is a reflexive reaction to anxiety over the pandemic.”