President Biden Tests Negative for COVID-19 One Week After Rebound Diagnosis

President Joe Biden is believed to be through his second bout of COVID-19.

On Saturday afternoon the president's physician, Dr. Kevin O'Connor, announced that Biden had received a negative test, seven days after his second COVID diagnosis.

"In an abundance of caution, the President will continue his strict isolation measures pending a second negative test," O'Connor wrote in a letter.

Biden, 79, first tested positive for COVID on the morning of Thursday, July 21, after feeling under the weather the night prior. Dr. Kevin O'Connor, the president's physician, immediately moved him to isolation and began treating him with Paxlovid.

By the end of Biden's five-day Paxlovid treatment he was feeling back to normal and received a negative test, allowing him to resume his schedule in person with direction that he would need to be closely monitored and keep a tight-fitting mask on around others for at least 10 days.

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O'Connor warned the public in advance that patients treated with Paxlovid sometimes experience a phenomenon called "rebound COVID," in which the virus returns a short while after overcoming it.

Sure enough, Biden experienced a rebound on July 30 — and while he felt okay and his vitals remained "entirely normal," he had to reenter isolation.

Saturday's negative test offers hope that Biden can soon resume regular activities. Though he has continued to work throughout both waves of the virus, the president has been unable to spend time with his family and colleagues in person, a time in which his administration executed a historic airstrike on an al Qaeda leader, his office has been pressured to address escalating overseas conflicts, and his granddaughter turned 18.