President Joe Biden tested negative for Covid on Saturday but will continue to self-isolate until he tests negative a second time, his doctor said in a letter.
“The President is feeling great,” wrote White House physician Dr. Kevin O’Connor a week after 79-year-old Biden tested positive in a “rebound” case of Covid. “This morning, his SARS-CoV-2 antigen test was negative.”
“He will continue his strict isolation measures as described earlier pending a second negative test,” O’Connor said.
Biden, who has been fully vaccinated and boosted twice, first tested positive for Covid during a routine test on July 21 and was treated with the antiviral PaxLovid. The president tested negative for several days before testing positive again last Saturday in what O’Connor described as a “rebound” case.
O’Connor said in a letter last week that Biden was doing well and would not start treatment.
A small proportion of people taking paxlovid to treat covid experience a relapse. About 1% to 2% of people taking Paxlovid in Pfizer’s clinical trials tested positive for the coronavirus after testing negative. Dr. Ashish Jha, the White House’s COVID Response Coordinator, said the rebound rate is about 5% among the thousands of people taking the drug in real life.
Biden’s chief medical adviser, Dr. Anthony Fauci, who was diagnosed with COVID in June, said he also experienced a PaxLovid rebound.
The Centers for Disease Control and Prevention warned of a possible recurrence in May, and said people who test positive again may still be infectious and should resume isolation for at least five days.