O’Connor said in a letter that Biden symptoms have not recurred and the president “continues to feel quite well.”
“That being the case, there is no reason to restart treatment at this time, but we will obviously continue to watch closely,” O’Connor wrote. Biden will return to isolation at the White House, O’Connor added.
Biden was scheduled to travel to Wilmington, Del., on Sunday and Hemlock, Mich., on Tuesday, but both trips have been canceled, the White House said.
The trip to Michigan was for an event in support of a $52 billion bill to subsidize computer chip manufacturing and research and counter China’s influence, known as the CHIPS and Science Act. The legislation passed both houses of Congress this week and is awaiting Biden’s signature. It was unclear whether Biden would attend Tuesday’s event remotely.
Biden likely was infected with the BA.5 variant, O’Connor said last week, an omicron subvariant that has become dominant in the United States and is the most transmissible version of the virus so far. BA.5 has shown a remarkable ability to escape the immune protection provided by vaccines and previous coronavirus infection.
Biden emerged from his five-day self-isolation on Wednesday and gave a speech from the Rose Garden about how his mild Covid infection was a reflection of the administration’s pandemic response and the tools it has made widely available, including antivirals , home tests and reinforcers.
He held a series of public events this week in support of the CHIPS bill and the economy. Biden did not hold any public events on Friday.
While it is possible that Biden may have shed the virus during the days he tested negative, it is unlikely that he would have been able to transmit the virus given his negative antigen tests, said Abraar Karan, an infectious disease physician. and researcher at Stanford University.
Biden took off his mask for some of the events. White House press secretary Karine Jean-Pierre said Biden was still in compliance with guidelines from the Centers for Disease Control and Prevention because he was more than six feet away from others.
CDC guidance recommends that people self-isolate for five days after testing positive for the coronavirus and wear a mask for another five days when around others. Some experts have said the guidance could prompt people to return to work or leave isolation when they are still potentially contagious.
In addition to Biden, notable figures who experienced rebound infections include 81-year-old Anthony S. Fauci, the president’s top medical adviser, who contracted the coronavirus earlier this summer. Recurrent infection can also lead to further complications, as with the initial infection, but many people describe their symptoms as mild.
Paxlovid, which is taken in a five-day course, suppresses the amount of virus in a person’s system during treatment. Some experts theorize that rebound infections occur because the five-day course is too short and should be extended by a few days to make sure the virus is eradicated.
The CDC in late May noted that patients may test positive again after completing the five-day course of Paxlovid and advised such people to go back into isolation for at least five days.
Experts are divided on whether patients should start another course of Paxlovid if they withdraw. Fauci later revealed that he received a second course of Paxlovid after getting a rebound infection.
Biden addressed his recovery on Twitter on Saturday, but assured people that he was still working and would resume traveling soon.
“People, today I tested positive for COVID again. It happens to a small minority of people,” Biden wrote on Twitter. “I have no symptoms, but I will isolate myself for the safety of everyone around me. I’m still at work and will be back on the road soon.”
Dan Diamond contributed to this report.
