COVID-19 infections can rebound for some people. It’s unclear why
Seemingly recovered people can have symptoms return or get another positive test
![Pink and white Paxlovid pills on a Paxlovid box with the Pfizer logo](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2022/08/081022_eg_paxlovid-rebound_feat.jpg?fit=1030%2C580&ssl=1)
Researchers aren’t sure why some coronavirus infections can rebound, including cases after people stop taking the antiviral drug Paxlovid (shown).
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