The 79-year-old Biden, who is fully vaccinated and double boosted, is "experiencing very mild symptoms," the White House says.
Biden tested posted after a trip to Somerset, Massachusetts on Wednesday, July 20.
Biden has begun taking the therapeutic Paxlovid, the White House said.
"Consistent with CDC guidelines, he will isolate at the White House and will continue to carry out all of his duties fully during that time," the White House said. "He has been in contact with members of the White House staff by phone this morning, and will participate in his planned meetings at the White House this morning via phone and Zoom from the residence."
CNN reported that White House COVID advisor Dr. Ashish Shah said Biden did not have a fever on Thursday morning, but was experiencing fatigue and a runny nose.
"Consistent with White House protocol for positive COVID cases, which goes above and beyond CDC guidance, he will continue to work in isolation until he tests negative," the White House said. "Once he tests negative, he will return to in-person work.
"Per standard protocol for any positive case at the White House, the White House Medical Unit will inform all close contacts of the President during the day today, including any members of Congress and any members of the press who interacted with the President during yesterday’s travel."
Prior to Thursday, Biden's previous test for COVID was Tuesday, July 19 when he had a negative test result, the White House said.
First Lady Jill Biden, who is visiting Detroit on Thursday, tested negative on Thursday. She had visited New Haven, Connecticut on Wednesday.
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