Why do some people who take Paxlovid for COVID get ‘rebound’ symptoms?

Or why do they test positive again, like President Biden? asks Lara Herrero, Griffith University For many people with COVID, their recovery isn’t linear. United States President Joe Biden is one such person – he continues to test positive for SARS-CoV-2, the virus that causes COVID, and has experienced the return of a “loose cough”.