Biden's latest COVID-19 'rebound' case has researchers evaluating link to anti-viral drug

President Joe Biden has tested positive for COVID-19 again on Sunday. It's the latest example of a rebound case after taking the anti-viral drug Paxlovid. 

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Health experts say during clinical trials, rebound cases happened in only 1 to 2% of people.

However, with more instances of rebound cases happening, researchers now re-evaluating the length of time that the drug Paxlovid is administered.

In a brief Twitter video update Saturday, Biden said, "I’m feeling fine, everything’s good." 

The announcement comes four days after the President tested negative, and was cleared from his first positive test on July 21st.

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In a memo, White House physician Dr. Kevin C. O'Connor said the President will be following strict isolation procedures after testing positive again. 

"The president has experienced no re-emergence of symptoms and continues to feel quite well," the memo read. "This being the case, there is no reason to reinitiate treatment (of Paxlovid) at this time, but we will obviously continue close observation."

"The official policy of the of the US Government is that is still a rare event, but I have a feeling it's probably happening on a much more frequent basis than we currently understand," Dr. Peter Hotez, a vaccine expert with Baylor College of Medicine said.

Similar to President Biden and his chief medical advisor, Dr. Anthony Fauci, vaccine expert Dr. Peter Hotez also experienced a rebound case of COVID-19 after taking the anti-viral drug Paxlovid.


"It seems to be, I think that there's more virus in the cells and there's not enough of the drug getting into the cells, so the question is, would people benefit for a longer quote from a longer, of course, of the drug maybe seven to 10 days, instead of five days," Dr. Hotez added.

Despite the higher anecdotal increase of Paxlovid rebound cases, Dr. Hotez believes the drug has still proven effective in fighting off severe cases of the Omicron sub-variant Ba-5. 

"If you have risk factors - in my case, age, or other factors, then yes, I would still recommend taking Paxlovid," Dr. Hotez said. "It's still worth taking it because that, in combination of being fully vaccinated and double boosted, it means that you're not going to go to the hospital or the intensive care unit because of this virus."