Findings: In this cohort study of 10 Massachusetts school districts, the secondary attack rate of SARS-CoV-2 in schools was 2.2% during the 2020-2021 school year and 2.8% in the fall of 2021. Factors associated with transmission in schools changed over time, although a greater social vulnerability index was associated with transmission in both periods.
AbstractImportance: School-associated SARS-CoV-2 transmission is described as uncommon, although the true transmission rate is unknown.
Objective: To identify the SARS-CoV-2 secondary attack rate (SAR) in schools and factors associated with transmission.
Design, Setting, and Participants: This cohort study examined the risk of school-based transmission of SARS-CoV-2 among kindergarten through grade 12 students and staff in 10 Massachusetts school districts during 2 periods: fall 2020/spring 2021 (F20/S21) and fall 2021 (F21)...
Main Outcomes and Measures: Potential factors associated with transmission, including grade level, masking, exposure location, vaccination history, and Social Vulnerability Index (SVI), were analyzed using univariable and multivariable logistic regression models...
Conclusions
The findings of this longitudinal cohort study of K-12 schools in Massachusetts, based on detailed school-based contact tracing during the 2020-2021 school year and fall semester of 2021, indicate that the SAR of SARS-CoV-2 among school-based contacts was low."
Open Access: This is an open access article distributed under the terms of the CC-BY License. © 2023 Nelson SB et al. JAMA Health Forum.