The impact of school-based mitigation measures on the transmission of respiratory pathogens: the case of SARS-CoV-2.

BACKGROUND

School-based mitigation measures can curb transmission of severe respiratory pathogens but may also impose high societal costs. Understanding their impact at the population level is key for pandemic preparedness evaluations.

METHODS

We developed an individual-based model of SARS-CoV-2 transmission in households, schools, and the general community, calibrated to epidemiological estimates from complete contact tracing data collected in the province of Reggio Emilia, Italy, during March-April 2021 (a period characterized by the dominance of the Alpha variant and strict community restrictions). We quantified the impact of school-based mitigation measures, including distance-learning mandates, reactive class quarantines, and periodic screening.

RESULTS

Unmitigated transmission in schools would increase the population-level SARS-CoV-2 reproduction number from 0.94 (95% confidence interval [CI]: 0.84-1.03) to 1.38 (95% CI: 1.29-1.47), substantially amplifying COVID-19 morbidity and mortality. Intensive contact tracing with reactive class quarantines would reduce disease burden but would be insufficient to prevent widespread epidemic growth. Weekly universal screening of students and teachers with highly specific rapid tests, on top of contact tracing and reactive class quarantines, could effectively reduce the spread of infections and maintain a high level of in-person education.

CONCLUSIONS

For highly transmissible severe respiratory infection with significant cryptic transmission, distance learning mandates may be necessary to protect vulnerable populations. However, weekly screening in schools may offer a viable strategy to preserve in-person education.