First lady Jill Biden has once again tested positive for COVID-19 in a “rebound” case of the virus, her office said in a statement Wednesday.

The statement added that Biden “has experienced no reemergence of symptoms” and will remain in isolation in Delaware.

The White House said that President Biden, who returned to Washington Wednesday morning after spending much of the previous two weeks in South Carolina and Delaware, had tested negative earlier in the day. However, the administration has previously said that the president was considered a close contact of his wife and would wear a mask for 10 days when indoors and around others.

The first lady initially tested positive Aug. 16 after developing “cold-like symptoms” near the end of the first family’s stay on Kiawah Island, S.C. Jill Biden previously received two doses of the COVID-19 vaccine as well as a booster shot.

Joe Biden initially tested positive for COVID on July 21, shortly after returning from a trip to the Middle East. The president tested negative five days after his initial infection, but also experienced a “rebound” case of the coronavirus days later.

The president was cleared to travel again Aug. 7, after another eight days in isolation.