President Joe Biden, 79, tested positive for COVID-19 and is experiencing “mild symptoms,” according to White House press secretary Karine Jean-Pierre.

According to CNN, this is the first time Biden has tested positive for COVID-19, and he last tested negative on Tuesday, per Jean-Pierre.

Vice President Kamala Harris and first lady Jill Biden have tested negative on Thursday, CNN reported.

“This morning, President Biden tested positive for Covid-19. He is fully vaccinated and twice boosted and experiencing very mild symptoms. He has begun taking Paxlovid,” she said, referring to Pfizer’s antiviral drug, which is available via emergency use authorization from the US Food and Drug Administration for treatment of mild to moderate Covid-19 in people 12 and older who are at high risk of severe illness. It requires a doctor’s prescription.