Understanding Covid rebound cases: UW Health expert explains Paxlovid connection

 

MILWAUKEE (CBS 58) -- An update Monday from President Joe Biden's doctor says he is still testing positive for Covid, but doing well.

The President tested negative last Tuesday after his initial case, only to rebound Saturday with another positive test.

The President's news raised some questions about how rebound cases happen and who is at risk.

Dr. Jeff Pothof, the chief quality officer and an emergency medical physician at UW Health, tells CBS 58 rebound cases are currently rare and not severe.

Dr. Pothof said a small percentage of people who take Paxlovid for a Covid infection and test negative could test positive again 2-8 days later.

Pothof explained that new positive test is not a reinfection.

"It's a reactivation or a rebound, it's the same exact Covid you had, just trying to make a bit of a comeback at the end there," Pothof said.

Right now, rebound cases are only emerging for some people who took the anti-Covid medication Paxlovid to fight the virus.

"When you take Paxlovid, it really significantly disrupts the virus' ability to replicate. That gives your immune system a chance to kind of catch up and turn the tides on the virus," Pothof said.

For a very small percentage of people, all traces of the infection aren't eliminated during the treatment.

"For folks whose immune systems are a little bit slower or aren't quite as quick, the virus after taking the Paxlovid has a little bit left, enough where it can replicate enough to turn a test positive," Pothof said.

That positive test is considered the "rebound" case. The upside is that rebound symptoms are usually mild or non-existent, like in President Biden's case.

"There's been zero cases of severe disease or death or anyone getting too ill from these rebound cases," Pothof said.

The downside to a rebound infection is that you will be considered contagious again.

"You go back into isolation for five days. So, it's more of an inconvenience than a health problem," Pothof said.

Dr. Pothof stresses that people should not let the possibility of a rebound case discourage eligible people from taking Paxlovid after testing positive the first time.

The medication reduces the likelihood of being admitted for COVID by 80%.