ABSTRACT
Background: Further evidence is needed to understand the contribution of schools and daycares to the spread of COVID-19 in the context of diverse transmission dynamics and continually evolving public health interventions. The Enfants et COVID-19: Etude de seroprevalence (EnCORE) study will estimate the seroprevalence and seroconversion of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among school and daycare children and personnel. In addition, the study will examine associations between seroprevalence and socio-demographic characteristics and reported COVID-19 symptoms and tests, and investigates changes in health, lifestyle and well-being outcomes. Methods: This study includes children and personnel from 62 schools and daycares in four neighbourhoods in Montreal, Canada. All children age 2-17 years attending one of the participating schools or daycares and their parents are invited to participate, as well as a sample of personnel members. Participants respond to brief questionnaires and provide blood samples, collected via dried blood spot (DBS), at baseline (October 2020-March 2021) and follow-up (May-June 2021). Questionnaires include socio-demographic and household characteristics, reported COVID-19 symptoms and tests, potential COVID-19 risk factors and prevention efforts, and health and lifestyle information. Logistic regression using generalized estimating equations will be used to estimate seroprevalence and seroconversion, accounting for school-level clustering. Discussion: The results of the EnCORE study will contribute to our knowledge about SARS-CoV-2 transmission in schools and daycares, which is critical for decisions regarding school attendance and the management of school outbreaks through the remainder of this school year and beyond. Keywords SARS-CoV-2; COVID-19; Children; School; Serology; Protocol; Canada