After SARS-CoV-2 exposure, a 14-day quarantine is standard among university athletes. But shorter quarantines for these athletes, along with mid-quarantine testing, may improve their compliance without increasing the risk that they’ll infect others, a new study suggests.

Researchers analyzed data from 620 U.S. college athletes who tested positive for SARS-CoV-2 while in quarantine after exposure to the virus.

Nearly half (49%) tested positive by the second day of quarantine, and 73% did by day 5.

The rate of positive tests declined over the quarantine period.

Among athletes who were still negative at day 5 of quarantine, the estimated probability of having a positive test result was 26.9% after day 5; 14.2% after day 7; and 4.7% after day 10. According to the authors, the probability of receiving positive test results after day 10 of quarantine is low.

Of 29 athletes who tested positive between days 11 and 14, 89.7% had not been tested previously during their quarantine, according to the findings.

More athletes reported exposure to COVID-19 at social gatherings (40.7%) and from roommates (31.7%) than from athletic activities (12.7%), the study found. It was published Jan. 8 in the U.S. Centers for Disease Control and Prevention’s Morbidity and Mortality Weekly Report.

The findings support shortened quarantine options for college athletes, given the low proportion who tested positive after 10 days, according to study author Dr. Catherine O’Neal, an infectious disease specialist at Louisiana State University.

“This data supports the CDC’s new recommendation and highlights the importance of mid-quarantine testing as an effective way to detect asymptomatic infection in this population,” she said in a university news release.

“The revised quarantine guidance from CDC is an important step in reducing the hardship of a 14-day quarantine while maintaining public safety,” said O’Neal, LSU’s representative on the NCAA Southeastern Conference Committee on Return to Activity and Medical Guidance Task Force. The conference includes 14 universities.

“Routine surveillance for COVID-19 in athletes participating in NCAA college athletics provided the opportunity for a critical evaluation of the quarantine period in the 20-year-old population,” O’Neal said.

More information

The U.S. Centers for Disease Control and Prevention has more on COVID-19.

SOURCE: Louisiana State University, news release, Jan. 12, 2021