Question: A friend of mine got a Covid test after experiencing mild cold symptoms because he is 70 and has RA. His test was positive. He took a second test a week later (around 4-5 days ago after no longer having symptoms and his test was positive again (got results 2-3 days ago). He is thinking he can leave quarantine because his symptoms have been gone for over 10 days. Is this correct, even though he tested positive again?

Answer: Your friend is correct!  CDC recommends using a symptoms-based strategy to end self-isolation (Table 1).  From your description, it sounds like your friend meets all the criteria– his illness was not severe and he is not severely immunocompromised, it’s been at least 10 days since symptoms began, he’s gone at least 24 hours fever-free without fever-reducing medication, and his symptoms have improved (he doesn’t even have symptoms anymore!).  The reason that we don’t rely on tests to end isolation is that PCR tests in particular can pick up virus remnants for a long time, much longer than a person is infectious.  If we relied on a test-based strategy to end isolation, folks would be isolating for much longer than necessary.  For more background on this testing issue, check out our Q&A of 10/24. 

Table 1. Symptoms-based Strategy to End Isolation (from CDC)