Biden still COVID positive but "feels very well," doctor says

President Biden tested positive for COVID-19 again Thursday and is still experiencing "a very occasional cough" which is "improving," his physician said in a letter.

The big picture: Biden had tested negative following his first bout with the virus last week after finishing his five-day course of the treatment Paxlovid. But the president has tested positive for a "rebound" case of COVID since Saturday.

Be smart: "Rebound" cases of COVID are possible for those who take Paxlovid, but it remains relatively rare, a Mayo Clinic study released in June found.

What he's saying: The president "feels very well," Biden's doctor, Kevin O'Connor wrote on Thursday.

• "He is still experiencing a very occasional cough, but the cough is improving," O'Conner added.
• "His temperature, pulse, blood pressure, respiratory rate and oxygen saturation remain entirely normal. His lungs remain clear," O'Conner added, noting that Biden is continuing to follow strict isolation measures.