Washington — President Biden has tested positive for COVID-19, the White House confirmed Wednesday.

White House press secretary Karine Jean-Pierre said in a statement that Mr. Biden tested positive earlier in the day after an event in Las Vegas. He was poised to address the annual conference of the Hispanic civil rights and advocacy group UnidosUs, but its president, Janet Murguía, announced that he would no longer be able to attend.

Jean-Pierre said the president is vaccinated and boosted and is experiencing mild symptoms.

"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," she said. "The White House will provide regular updates on the President's status as he continues to carry out the full duties of the office while in isolation."

Mr. Biden's doctor said in a note distributed by the White House that he had upper respiratory symptoms Wednesday afternoon, including a runny nose and a "non-productive cough." The doctor said Mr. Biden's respiratory rate, temperature and pulse oximetry are all normal, and the president received a first dose of Paxlovid.

Though Mr. Biden "felt okay" for his first event in Nevada, he was tested for COVID after not feeling better, the note read.

The president told reporters before departing Las Vegas, "I feel good." In a social media post, Mr. Biden thanked people for their well wishes and said that he will "continue to work to get the job done for the American people" while recovering.

Speaking to CBS News' John Dickerson Wednesday evening, CBS News chief medical correspondent Dr. Jonathan LaPook noted that he was "very interested" that Mr. Biden had been given a dose of Paxlovid.

"He has been on a blood thinner called apixaban, which is Eliquis," LaPook said. "And Eliquis does have an interaction with Paxlovid, which is why you have to be very careful when you give the two together. The Paxlovid can increase the level of the Eliquis."

The president arrived in Nevada on Monday for a series of events aimed at reaching core constituencies as he battles calls from within the Democratic Party to withdraw from the presidential race following his startling performance at the first presidential debate on June 27. Mr. Biden participated in an interview with BET's Ed Gordon on Tuesday and delivered remarks at the 115th NAACP National Convention in Las Vegas.

His schedule Wednesday included another full slate of events, including a radio interview with Univision and the remarks at the UnidosUS annual conference.

Murguía announced ahead of Mr. Biden's scheduled remarks that she spoke with the president and learned of his COVID diagnosis.

"Regrettably, I was just on the phone with President Biden and he shared his deep disappointment at not being able to join us this afternoon," she said. "The president has been at many events as we all know and he just tested positive for COVID."

Murguía said the president relayed that "we're not going to get rid of him that quickly," and said the group will have a chance to hear from him in the future directly.

The president was set to return to Rehoboth Beach, Delaware, later in the evening, though that return has been moved up.

The U.S. Centers for Disease Control and Prevention recommends people with a respiratory virus stay home and away from others if experiencing symptoms. The agency said patients can resume normal activities when symptoms are improving and they have not had a fever for at least 24 hours.

Several top Biden administration officials have also tested positive for COVID-19 in recent weeks, including second gentleman Doug Emhoff and Health and Human Services Secretary Xavier Becerra. The nation is experiencing a summer surge of COVID, and the CDC reported last week that more than half of states are seeing "high" or "very high" levels of SARS-CoV-2, the virus that causes COVID-19, in wastewater testing.

The agency said the District of Columbia and 26 states are seeing "substantial increases" in COVID-19 emergency room visits, and across the country, the average share of emergency room patients with the virus is the highest its been since February.

— Alex Tin contributed to this report. 

Melissa Quinn

Melissa Quinn is a politics reporter for CBSNews.com. She has written for outlets including the Washington Examiner, Daily Signal and Alexandria Times. Melissa covers U.S. politics, with a focus on the Supreme Court and federal courts.

Twitter