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If we’ve learned anything over the past two and a half years, it’s that Covid-19 is one strange disease. The latest case in point: the coronavirus rebound.
The condition grabbed international attention last week when US President Joe Biden tested positive for the virus six days after testing negative following his first bout of the illness.
The White House said Biden, who is back in isolation, was experiencing a bit of a “loose cough” but did not have a fever and his lungs were “clear.”
The President tested positive again after being treated with the antiviral Paxlovid. White House officials had previously suggested a rebound case of Covid was unlikely, based on reports of cases around the country, but Biden’s doctors continued to monitor his health and test him.
Dr. Ashish Jha, the White House Covid response coordinator, said clinical data shows the rate of rebound infections is low and noted that even those who suffer them are still generally protected from serious illness.
Biden is not the only high-profile patient to develop the condition. National Institute of Allergy and Infectious Diseases Director Dr. Anthony Fauci also experienced rebound Covid-19. Unlike Biden’s, his symptoms got worse when they returned after treatment with Paxlovid, and his doctors prescribed another course of the drug.
Experts have been calling for more systematic research into the instances of rebound to understand who is most at risk and whether the standard five-day course of Paxlovid should be lengthened to prevent it.
Studies have shown that people can pass the infection to others during a rebound, which is another reason to try to understand it better.
The United States’ Centers for Disease Control and Prevention (CDC) issued a health alert to doctors in May about the potential for Covid-19 rebound, saying symptoms sometimes come back, and that may just be how the infection plays out in some people, regardless of whether they’re vaccinated or treated with medications like Paxlovid.
The CDC said most cases of rebound involve mild disease and that Paxlovid “continues to be recommended for early-stage treatment of mild to moderate COVID-19 among persons at high risk for progression to severe disease.”
Pfizer, the company that makes Paxlovid, has said its studies showed rebounds were rare, and that they happened in both people who took the drug and those who took a placebo pill. Because investigators noted the phenomenon in both groups, the company doesn’t believe it is tied to the medication.
YOU ASKED. WE ANSWERED.
Q: How does Paxlovid work?
A: Considered a game-changer when it was authorized in December because of its strong performance in lowering the risk of severe Covid-19, Paxlovid – in combination with vaccines and boosters – is thought to be one of the best ways to protect people at high risk for severe illness.
The drug suppresses the coronavirus, blocking an enzyme that helps it reproduce inside the body.
As with all antivirals, the treatment is thought to work best if started within five days of the first symptoms appearing.
Clinical trials of Paxlovid showed that it …