(FILES) In this file photo taken on July 27, 2022, US President Joe Biden removes his protective mask while arriving to deliver remarks in the Rose Garden of the White House in Washington, DC. - US President Joe Biden on August 6, 2022, tested negative for Covid-19, days after coming down with a second bout of the illness. (Photo by Brendan Smialowski / AFP)

US President Joe Biden has tested negative for the corona virus. But he will remain in isolation until there is a second negative antigen test, his doctor Kevin O’Connor said on Saturday, according to a White House statement. “The President continues to feel very good,” O’Connor said.

The 79-year-old Biden tested positive for the first time on July 21. He was treated with the Covid drug Paxlovid and came negative a few days later.

But on Saturday a week ago, the US President tested positive again – as a result of the so-called rebound effect that can occur after treatment with Paxlovid.

Biden is fully vaccinated against the coronavirus and boosted twice. He is the oldest president the United States has ever had.