The Bidens have been vacationing in South Carolina since August 10, and the 71-year-old first lady began experiencing symptoms on Monday.

Jill Biden, like her husband, has been twice-vaccinated and twice-boosted with the Pfizer vaccine. She has been prescribed the antiviral drug Paxlovid and will isolate at the vacation home for at least five days.

"Close contacts of the First Lady have been notified," her communications director, Elizabeth Alexander, said in a statement on Tuesday.

"She is currently staying at a private residence in South Carolina and will return home after she receives two consecutive negative COVID tests."

President Joe Biden tested negative on Tuesday morning, the White House said, but would be wearing a mask indoors for 10 days. He recovered from a rebound case of the virus on August 7.

"Consistent with CDC guidance because he is a close contact of the first lady, he will mask for 10 days when indoors and in close proximity to others," the White House said.

It said it would increase the president's testing cadence and report those results.

Australian Associated Press