COVID-19: Testing & Quarantine Duration? / College Campuses

First, a study examined the time from quarantine to positive SARS-CoV-2 test in college athletes. More of the 1800 quarantined athletes had exposures from social gatherings (41%) or roommates (32%) than from their respective sports (13%). Of the 25% who tested positive during quarantine, the mean time until positive test result was 3.8 days from the start of quarantine. The probability of having a positive test fell to less than 5% after day 10. The authors say the results support current CDC guidance for testing options to shorten quarantine.

MMWR article on athlete quarantines

Along these same lines — though not in a college setting — another MMWR study noted that in Vermont, a third of contacts who tested positive on PCR 7 days after exposure were asymptomatic. (Vermont’s policy is to shorten quarantine time for asymptomatic contacts who test negative on day 7.) None of the people who were negative on day 7 tested positive during days 8–14. The authors write: “Allowing asymptomatic persons to shorten quarantine with a negative test at day 7 or later has not been demonstrated to result in transmission of SARS-CoV-2, indicating that the policy has been effective.”

MMWR article on Vermont quarantine 

MMWR article on in-person instruction at colleges