SARS-CoV-2 infection prevention and control measures in Belgian schools between December 2020 and June 2021 and their association with seroprevalence: a cross-sectional analysis of a prospective cohort study, Callies, Milena, Kabouche Ines, Desombere I, Merckx Joanna, Roelants Mathieu, Vermeulen Melissa, and Duysburgh Els , BMC Public Health, Jan-12-2023, Volume 23, Issue 1, (2023)