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Prevalence of Positive Rapid Antigen Tests After 7-Day Isolation Following SARS-CoV-2 Infection in College Athletes During Omicron Variant Predominance. JAMA network open Tsao, J., Kussman, A., Segovia, N. A., Abrams, G. D., Boehm, A. B., Hwang, C. E. 2022; 5 (10): e2237149

Abstract

Importance: The US Centers for Disease Control and Prevention shortened the recommended isolation period for SARS-CoV-2 infection from 10 days to 5 days in December 2021. It is unknown whether an individual with the infection may still have a positive result to a rapid antigen test and potentially be contagious at the end of this shortened isolation period.Objective: To estimate the proportion of individuals with SARS-CoV-2 infection whose rapid antigen test is still positive starting 7 days postdiagnosis.Design, Setting, and Participants: This case series analyzed student athletes at a National Collegiate Athletic Association Division I university campus who tested positive for SARS-CoV-2 between January 3 and May 6, 2022. Individuals underwent rapid antigen testing starting 7 days postdiagnosis to determine whether they could end their isolation period.Exposures: Rapid antigen testing 7 days after testing positive for SARS-CoV-2.Main Outcomes and Measures: Rapid antigen test results, symptom status, and SARS-CoV-2 variant identification via campus wastewater analysis.Results: A total of 264 student athletes (140 [53%] female; mean [SD] age, 20.1 [1.2] years; range, 18-25 years) representing 268 infections (177 [66%] symptomatic, 91 [34%] asymptomatic) were included in the study. Of the 248 infections in individuals who did a day 7 test, 67 (27%; 95% CI, 21%-33%) tests were still positive. Patients with symptomatic infections were significantly more likely to test positive on day 7 vs those who were asymptomatic (35%; 95% CI, 28%-43% vs 11%; 95% CI, 5%-18%; P<.001). Patients with the BA.2 variant were also significantly more likely to test positive on day 7 compared with those with the BA.1 variant (40%; 95% CI, 29%-51% vs 21%; 95% CI, 15%-27%; P=.007).Conclusions and Relevance: In this case series, rapid antigen tests remained positive in 27% of the individuals after 7 days of isolation, suggesting that the Centers for Disease Control and Prevention-recommended 5-day isolation period may be insufficient in preventing ongoing spread of disease. Further studies are needed to determine whether these findings are present in a more heterogeneous population and in subsequent variants.

View details for DOI 10.1001/jamanetworkopen.2022.37149

View details for PubMedID 36255722