What is COVID rebound? Paxlovid treatment could present positive test results days later

Dr. Unnasch says about 5% of the people who take the drug see COVID Rebound two or three days later. President Joe Biden is now isolated after COVID rebound. https://www.abcactionnews.com/news/coronavirus/what-is-covid-rebound-paxlovid-treatment-could-present-positive-test-results-days-later