U.S President Joe Biden has tested positive for COVID-19.

White House says that Biden tested positive for COVID following his first campaign event in Las Vegas.

“He is vaccinated and boosted and he is experiencing mild symptoms,” White House Press Secretary Karine Jean-Pierre says. “He will be returning to Delaware where he will self-isolate and will continue to carry out all of his duties fully during that time.”

His doctor, Kevin O’Connor, says he had upper respiratory symptoms, to include rhinorhea (runny nose) and non-productive cough, with general mailaise.

“He felt okay for his first event of the day, but given that he was not feeling better, point of care testing for COVID-19 was conducted, and the results were positive for the COVID-19 virus. Given this, the President will be self-isolating in accordance with CDC guidance for symptomatic individuals,” O’Connor says.

Biden’s symptoms remain mild. “His respiratory rate is normal at 16, his temperature is normal at 97.8 and his pulse oximetry is normal at 97%. The President has received his first dose of Paxlovid. He will be self-isolating at his home in Rehoboth.”

Biden, 81, had on Wednesday spent his time visiting supporters in Las Vegas and speaking at an event. He cancelled a campaign speech later in the night.

In a tweet, Biden confirmed his illness, but said that he was feeling good.

“I tested positive for COVID-19 this afternoon, but I am feeling good and thank everyone for the well wishes. I will be isolating as I recover, and during this time I will continue to work to get the job done for the American people.”

The illness comes at a time when Biden is facing increasing pressure from a section of Democrats to end his bid for re-election and step aside in favour of a younger contender.

The ABC reports that both Senate Majority Leader Chuck Schumer and House Majority Leader Hakeem Jefferies – the top two Democrats in the US Congress – separately met Biden privately to convince him into dropping out of the race,