President Joe Biden is making strides in recovering from his Covid-19 infection, as his cough, body aches and other symptoms have “diminished considerably” after three full days of treatment with the Paxlovid antiviral drug, White House Dr. Kevin O’Connor reported.

The president’s main symptom currently is a lingering sore throat, O’Connor said in a statement on Sunday, adding, “This is most likely a result of lymphoid activation as his body clears the virus and is thus encouraging.”

Biden tested positive for Covid-19 on Thursday, despite having been fully vaccinated against the virus and receiving two booster shots. He was infected with the BA.5 variant of the virus, currently the dominant strain in the US, White House Covid-19 response coordinator Dr. Ashish Jha confirmed on Sunday.

Biden hasn’t been seen publicly since Friday, when he participated in a remote meeting with his economic advisors. The president, 79, repeatedly interrupted his comments to cough. He began by saying in a raspy voice, “Let me start by apologizing my voice. I’m feeling much better than I sound.”

“His voice remains a bit deep,” O’Connor said in Sunday’s statement. “His pulse, blood pressure, respiratory rate and temperature all remain normal.”

Jha claimed that Biden is recovering well largely because he was fully vaccinated. None of the 17 people who were determined to have been in close contact with the president around the time he may have been infected, including White House staffers and members of Congress, has tested positive for Covid-19, the doctor added.