Dr. Sanjay Gupta: The complicated calculus of mask-wearing

9:55am PDT - May 9th, 2021    cdc guidelines - CNN

It's not easy right now to know when to wear a mask, but there are objective ways to figure this out. To start, ask yourself, what is the likelihood that I'm going to breathe in someone else's air and that air could have enough virus to infect me?