How long after the COVID-19 booster is it effective?
How long after the COVID-19 booster is it effective?
The first COVID-19 booster shot is now in the rearview mirror for millions of Americans — for the 28% who got it, at least — but new data finds it’s less effective after about 4 months. The CDC has already recommended a second booster for immunocompromised people. < Feb 18, 2022
