WASHINGTON — President Joe Biden is once again negative for COVID, after a rare rebound case that had him testing positive for the virus again shortly after his first bout with it.
"The president continues to feel very well. Given his rebound positivity which reported last Saturday, we have continued daily monitoring," wrote Dr. Kevin O'Connor, the president's physician, in a letter. "This morning, his SARS-CoV-2 antigen testing was negative."
Last Saturday, days after ending his COVID-19 isolation, Biden tested positive for the virus again.
Biden's treatment for the first round of the illness included a five-day course of Paxlovid, an antiviral drug used to treat COVID-19 that has helped prevent more severe illness. His physician said Biden is one of a small percentage of Paxlovid patients who "rebound" and test positive again.
"After testing negative on Tuesday evening, Wednesday morning, Thursday morning and Friday morning, the President tested positive late Saturday morning, by antigen testing," O'Connor wrote in a letter that weekend. "This in fact represents 'rebound' positivity."
Since then, as with the first time he tested positive last month, the White House has been giving daily briefings on Biden's health as he stays in isolation.
The president will stay isolated from other White House staffers until he receives a second negative antigen test — likely later Saturday or Sunday morning.
Biden's travel has been on hold as he awaited a negative test. He plans to visit Kentucky on Monday to view damage from catastrophic flooding and meet with families.
Regulators are still studying rebound cases, but the CDC in May warned doctors that it has been reported to occur within two days to eight days after initially testing negative for the virus.
“Limited information currently available from case reports suggests that persons treated with Paxlovid who experience COVID-19 rebound have had mild illness; there are no reports of severe disease,” the agency said at the time.
White House COVID-19 coordinator Dr. Ashish Jha told reporters on Monday that “the clinical data suggests that between 5 and 8 percent of people have rebound” after Paxlovid treatment.
U.S. health officials have encouraged those who test positive to consult their doctors or pharmacists to see if they should be prescribed the treatment, despite the rebound risk.
Biden is fully vaccinated and has received two booster doses. He was diagnosed with the highly transmissible BA.5 variant of COVID, but had a mild bout with the virus. O'Connor consistently wrote in his updates that Biden's vital signs remained strong, and his temperature only became briefly elevated. He suffered from a runny nose, cough, sore throat and some body aches.