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Quarantine Elimination for K-12 Students With Mask-on-Mask Exposure to SARS-CoV-2
Angelique E Boutzoukas1,2, Kanecia O Zimmerman1,2,3, Daniel K Benjamin1,2,3
1Duke Clinical Research Institute.
Objectives:
With layered mitigation strategies, there are low rates of secondary transmission of severe acute respiratory syndrome coronavirus 2; therefore, quarantine after close-contact exposure to severe acute respiratory syndrome coronavirus 2 in the kindergarten through 12th grade (K-12) setting further disrupts in-person learning with uncertain benefit. We explored the impact of eliminating quarantine for students with mask-on-mask exposures to coronavirus disease 2019 (COVID-19) on associated secondary transmission in schools.
Methods:
This observational study was conducted in a large K-12 public school district in Omaha, Nebraska (August 1, 2020, to March 15, 2021). We assessed primary and secondary COVID-19 infections in teachers and staff, frequency of quarantine for students and staff, and the impact of eliminating quarantine on secondary transmission in mask-on-mask exposure settings.
Results:
A total of 18 632 and 19 604 students and 2855 staff attended in-person learning in the fall and spring semesters, respectively; 1856 primary infections were among students and staff. Despite 3947 student quarantines in the fall and 1689 student quarantines in the first 10 weeks of spring semester instruction, there were only 2 cases of secondary transmission. A local policy change removed quarantine requirements for students with mask-on-mask exposure to COVID-19. Required quarantines in the spring semester reduced by 41% per primary infection compared with the fall; no student who qualified to avoid quarantine developed a secondary infection.
Conclusions:
School-based COVID-19 transmission was exceptionally low in this large K-12 Nebraska school district. Elimination of student quarantine after masked exposure to COVID-19 within school was not associated with secondary transmission. Elimination of unnecessary quarantine elimination may help maximize in-person learning in the 2021-2022 school year.
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