Biden again positive for coronavirus

WASHINGTON — President Biden tested positive for coronavirus again Saturday, slightly more than three days after he was cleared to exit coronavirus isolation, the White House said, in a rare case of “rebound” after treatment with an antiviral drug.

White House physician Dr. Kevin O’Connor said in a letter that Biden “has experienced no reemergence of symptoms, and continues to feel quite well.”

In accordance with Centers for Disease Control and Prevention guidelines, Biden will resume isolation for least five days. The agency says most rebound cases remain mild and that severe disease during that period has not been reported.

Biden, 79, was treated with the drug Paxlovid after he first tested positive on July 21. He tested negative last Tuesday and Wednesday. He was then cleared to leave isolation while wearing a mask indoors. His positive tests puts him among the minority of those prescribed the drug to experience a rebound case of the virus.

Regulators are still studying the prevalence and virulence of rebound cases, but the CDC in May warned doctors that it has been reported to occur within two 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.

When Biden was released from isolation on Wednesday, O’Connor said the president would “increase his testing cadence” to catch any potential rebound of the virus.