A letter issued by presidential physician Dr. Kevin O'Connor confirmed that President Joe Biden has tested positive for COVID-19 again. O’Connor described the case as a “rebound” positivity which is “observed in a small percentage of patients treated with Paxlovid." The letter was written by O’Connor and addressed to Karine Jean-Pierre, the White House Press Secretary. In it, the doctor notes that the president has experienced “no reemergence of symptoms, and continues to feel quite well.” Jean-Pierre also confirmed that the President is “asymptomatic, feeling fine, and working in isolation from the Residence to protect others." O’Connor also noted that Biden had tested negative in a series of tests since Tuesday evening before this positive result on Saturday.

In a tweet, Biden confirmed the result saying, “Folks, today I tested positive for COVID again. This happens with a small minority of folks. I’ve got no symptoms but I am going to isolate for the safety of everyone around me,” he added, “I’m still at work, and will be back on the road soon.” Biden first tested positive for COVID-19 on July 21 where he noted that he had been vaccinated and double-boosted, yet, was experiencing mild symptoms, including — per CNN, a “runny nose, fatigue, high temperature and a cough.” He was treated with a five-day course of Paxlovid which is used to treat mild to moderate cases of the virus.

The president had resumed events this week, although he wore a mask more frequently than in the past and the White House staff emphasized social distancing. Per CNN, Pfizer which makes Paxlovid has said that rebound cases are rare and there is no clear link to the medication and such cases.