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. 2022 Feb 1;149(12 Suppl 2):e2021054268K.
doi: 10.1542/peds.2021-054268K.

Secondary Transmission of COVID-19 in K-12 Schools: Findings From 2 States

Angelique E Boutzoukas  1   2 , Kanecia O Zimmerman  1   2   3 , Daniel K Benjamin  1   2   3 , Gregory P DeMuri  4 , Ibukunoluwa C Kalu  1   2 , Michael J Smith  2 , Kathleen A McGann  2 , Shawn Koval  5 , M Alan Brookhart  6 , Sabrina M Butteris  7
Affiliations

Secondary Transmission of COVID-19 in K-12 Schools: Findings From 2 States

Angelique E Boutzoukas et al. Pediatrics. .

Abstract

Objectives: We evaluated the impact of distancing practices on secondary transmission of severe acute respiratory syndrome coronavirus 2 and the degree of sports-associated secondary transmission across a large diverse cohort of schools during spring 2021.

Methods: Participating districts in North Carolina and Wisconsin and North Carolina charter schools offering in-person instruction between March 15, 2021 and June 25, 2021 reported on distancing policies, community- and school-acquired infections, quarantines, and infections associated with school-sponsored sports. We calculated the ratio of school-acquired to community-acquired infection, secondary attack rates, and the proportion of secondary transmission events associated with sports. To estimate the effect of distancing and bus practices on student secondary transmission, we used a quasi-Poisson regression model with the number of primary student cases as the denominator.

Results: During the study period, 1 102 039 students and staff attended in-person instruction in 100 North Carolina school districts, 13 Wisconsin school districts, and 14 North Carolina charter schools. Students and staff had 7865 primary infections, 386 secondary infections, and 48 313 quarantines. For every 20 community-acquired infections, there was 1 within-school transmission event. Secondary transmissions associated with school sports composed 46% of secondary transmission events in middle and high schools. Relaxed distancing practices (<3 ft, 3 ft) and increased children per bus seat were not associated with increased relative risk of secondary transmission.

Conclusions: With universal masking, in-person education was associated with low rates of secondary transmission, even with less stringent distancing and bus practices. Given the rates of sports-associated secondary transmission, additional mitigation may be warranted.

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Conflict of interest statement

CONFLICT OF INTEREST DISCLOSURES: Dr Boutzoukas receives salary support through the US Government Eunice Kennedy Shriver National Institute of Child Health and Human Development T32 training grant (1T32HD094671). Dr Zimmerman reports funding from the National Institutes of Health and US Food and Drug Administration. Dr Benjamin reports consultancy for Allergan, Melinta Therapeutics, and Sun Pharma Advanced Research Company. Dr Kalu reports funding from the Centers for Disease Control and Prevention’s Prevention Epicenters Program and consultancy for Infection Prevention Education Consultant (IP EC) Experts and Wayfair. Dr Smith reports being a site coinvestigator for Pfizer adult and pediatric vaccine trials. Dr Brookhart serves on scientific advisory committees for AbbVie, Amgen, Atara Biotherapeutics, Brigham and Women’s Hospital, Gilead, and Vertex; he receives consulting fees for and owns equity in NoviSci and TargetRWE; the other authors have indicated they have no financial relationships relevant to this article to disclose.

Figures

FIGURE 1
FIGURE 1
North Carolina reporting counties: representative map of North Carolina counties with at least 1 district reporting. Counties highlighted in purple had at least one school district reporting data to this study; counties in grey did not have any school districts reporting.
See this image and copyright information in PMC

References

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