biostudies-literatureUnknown5(4)Lachassinne EAssistance Publique - Hôpitaux de Paris<h4>Background</h4>The extent to which very young children contribute to the transmission of SARS-CoV-2 is unclear. We aimed to estimate the seroprevalence of antibodies against SARS-CoV-2 in daycare centres that remained open for key workers' children during a nationwide lockdown in France.<h4>Methods</h4>Children and staff who attended one of 22 daycare centres during a nationwide lockdown in France (between March 15 and May 9, 2020) were included in this cross-sectional, multicentre, seroprevalence study. Hospital staff not occupationally exposed to patients with COVID-19, or to children, were enrolled in a comparator group. The primary outcome was SARS-CoV-2 seroprevalence in children, daycare centre staff, and the comparator group. The presence of antibodies against SARS-CoV-2 in capiThe Lancet. Child & adolescent health256-264https://www.ebi.ac.uk/biostudies/studies/S-EPMC9180428biostudies-literatureSARS-CoV-2 transmission among children and staff in daycare centres during a nationwide lockdown in France: a cross-sectional, multicentre, seroprevalence study.PMC9180428Caseris MWannepain ELorrot MPinquier DLescano OGajdos VBrichler SBasmaci RHentgen VMasson RZahar JRCharbonnier LMestre NRabehi BCohen RLachassinne EGuilluy CNaud ABloch-Queyrat CRomain ASDommergues MAJung CVuillaume XHausherr EBoelle PYPinto Cardoso Gde Pontual LCOVIDOCRECHE collaboratorsAupiais CChosidow AVie le Sage FfalseSARS-CoV-2 transmission among children and staff in daycare centres during a nationwide lockdown in France: a cross-sectional, multicentre, seroprevalence study.<h4>Background</h4>The extent to which very young children contribute to the transmission of SARS-CoV-2 is unclear. We aimed to estimate the seroprevalence of antibodies against SARS-CoV-2 in daycare centres that remained open for key workers' children during a nationwide lockdown in France.<h4>Methods</h4>Children and staff who attended one of 22 daycare centres during a nationwide lockdown in France (between March 15 and May 9, 2020) were included in this cross-sectional, multicentre, seroprevalence study. Hospital staff not occupationally exposed to patients with COVID-19, or to children, were enrolled in a comparator group. The primary outcome was SARS-CoV-2 seroprevalence in children, daycare centre staff, and the comparator group. The presence of antibodies against SARS-CoV-2 in capi2021-01-01T00:00:00Z2021 Apr2026-05-09T18:57:13.554Z2025-04-05T19:57:52.788ZS-EPMC91804283357145010.1016/S2352-4642(21)00024-9