We've learned a lot about COVID-19 over the last few years. "If you have enough virus in your system to be turning one of these tests positive, that means your body probably hasn't yet fully cleared the infection," says Hay. The CDC guidance published online doesnt address this specific scenario, making it confusing for someone whose symptoms may have been gone for days, but is still testing positive at the end of the isolation period. So, to work out if positive tests mean people are infectious, scientists culture samples from these tests in petri dishes to see if more virus can grow, indicating that it's still alive and contagious. We're entering our third year of the COVID-19 pandemic and some people continue to test positive for coronavirus late into their infection. That includes wearing a mask when around others, avoiding travel and avoiding being around people who are high-risk for severe COVID-19. Read on to learn more. That means a friend or family member could spread COVID19 even if they don't show signs of being sick. This online tool can help you determine how many days to stay in isolation. All rights reserved. In some cases, we will recommend that it is not necessary to seek a PCR confirmatory test, she says. I feel like we somehow forgot that part, she said. Some researchers have criticized these rules pointing to research that shows some people may remain infectious after day five. Therefore, a positive result tends to mean the person has a high viral load, especially if symptoms appeared. But if you feel fine, it can be frustrating to wait, especially if you're in the subset of those who test positive past 10 days. Know My Rights About Surprise Medical Bills, This online tool can help you determine how many days to stay in isolation, Read the CDC's instructions for isolation and quarantine, Learn about CHOPs COVID-19 Vaccine Program here, 2022 The Childrens Hospital of Philadelphia. "We don't have anything that says definitely you are contagious or definitely you're not," says Dr. Emily Landon, an infectious disease specialist at UChicago Medicine. KHN (Kaiser Health News) is a national newsroom that produces in-depth journalism about health issues.