How common are Paxlovid rebound cases? Experts weigh in

President Joe Biden’s covid-19 “rebound” case has created concern for people around the world who are wondering if such cases are becoming more common.

Dr. Donald Yealy, UPMC’s chair of emergency medicine, defines a rebound case as having covid and then redeveloping some symptoms after fighting off the infection and feeling better for a few days, or having a positive test after having tested negative.

“This can happen to almost anyone,” Yealy said, “and we’ve known that for two years.”

Dr. Maureen Lichtveld, dean of the University of Pittsburgh Graduate School of Public Health, said a true “rebound” case means being infected with the same variant.

“We know, for example, that with the coronavirus there are a number of variants,” Lichtveld said. “So, if I’m infected with the BA.5 (subvariant), and then when BA.1 comes around and I get infected again, that not necessarily a rebound case.”

Yealy said the coronavirus continues to evolve.

“The virus changes usually in a couple different ways. It either makes itself easier to spread or changes how, once it’s inside your body, it reacts to the other tissues,” Yealy said. “It’s clearly become easier to spread, which is why we hear about re-infection more now than we did in the first year of the pandemic.”

Despite this, Yealy maintains that there is reason for optimism when it comes to covid based on these recent developments.

“Oddly enough (covid’s) effect on the total body does not seem to be getting worse, and in some ways might be getting better.”

Yealy said he’s not surprised at all that President Biden has experienced a “rebound” case.

“Nine times out of 10 it wouldn’t have happened,” Yealy said. “He’s doing all the right things, and he’s having a recovery path that looks very common. I expect that he’ll recover fully.”

Use of the covid-19 treatment Paxlovid, an antiviral pill, has increased in the United States, according to the White House.

But instances of covid cases returning after antiviral treatment have some people wondering about the role of Paxlovid in rebound cases.

“Paxlovid is most effective if it’s used at the earliest possible time,” Lichtveld said. “Since every medication has side effects, some of the side effects of Paxlovid — whether it’s nausea, or fever, or coughing — look just like somebody had covid again. They look just like each other.

“In this case, Paxlovid is behaving like covid and it isn’t. It’s really trying to help you get over that covid infection.”

Yealy said Paxlovid was developed to prevent serious illness, not to guarantee that there wouldn’t be fluctuations.

“The point of the vaccines and Paxlovid and monoclonal antibodies is to make sure you never get to serious illness,” Yealy said. “That your body can occasionally have a hiccup during your recovery and the virus being detected again doesn’t mean failure. That’s what I think we have to remind people.”

Dr. Brian H. Lamb, who specializes in adult internal medicine for the Allegheny Health Network, said people should not avoid using Paxlovid. Still, he still has concerns.

“Each study is a little bit different,” Lamb said, “But some studies are actually saying up to 12% of patients who’ve been treated with Paxlovid are having (rebounds), which is a little more than what they’re initial studies showed.

“Their studies showed that 1% to 2% of patients were at risk of having this second bout. These numbers are a little higher than we thought when we first started prescribing Paxlovid.”

Lamb also said more caution should be exercised when it comes to using Paxlovid.

“This isn’t something that everyone should just automatically ask for,” he said. “It doesn’t necessarily mean that you’re going to feel better faster. It doesn’t necessarily mean that you’re going to be able to come out of quarantine any faster.

“We really need to think about why we’re using it. Clinical trials show that it reduces hospitalization and death by 88% when given in the first five days of symptoms. Most of our younger, healthier people aren’t necessarily at risk for that to begin with.“