biostudies-literatureCarrat FANR (Agence Nationale de la Recherche)Agence Nationale de la RechercheInserm (Institut National de la Santé et de la Recherche Médicale) [#C20-26]ANRInserm (Institut National de la Santé et de la Recherche Médicale) [#C20–26]Fondation pour la Recherche MédicaleFondation pour la Recherche Médicale [#20RR052-00], Inserm (Institut National de la Santé et de la Recherche Médicale) [#C20-26]1458-1472https://www.ebi.ac.uk/biostudies/studies/S-EPMC8344948biostudies-literatureUnknown50(5)<h4>Background</h4>We aimed to estimate the seropositivity to anti-SARS-CoV-2 antibodies in May-June 2020 after the first lockdown period in adults living in three regions in France and to identify the associated risk factors.<h4>Methods</h4>Between 4 May 2020 and 23 June 2020, 16 000 participants in a survey on COVID-19 from an existing consortium of three general adult population cohorts living in the Ile-de-France (IDF) or Grand Est (GE) (two regions with high rate of COVID-19) or in the Nouvelle-Aquitaine (NA) (with a low rate) were randomly selected to take a dried-blood spot for anti-SARS-CoV-2 antibodies assessment with three different serological methods (ClinicalTrial Identifier #NCT04392388). The primary outcome was a positive anti-SARS-CoV-2 ELISA IgG result against the spike prInternational journal of epidemiologyAntibody status and cumulative incidence of SARS-CoV-2 infection among adults in three regions of France following the first lockdown and associated risk factors: a multicohort study.PMC8344948#ANR-10-COHO-06#ANR-20-COVI-000, #ANR-10-COHO-06#20RR052-00#ANR-20-COVI-000Artaud FSeveri GLai Cfor the SAPRIS and SAPRIS-SERO study groupsZins Mde Lamballerie XJusot FKab SFourie TLegot SNicol JBajos NSaba Villarroel PMRahib DDruesne-Pecollo NPriet SRenuy AGagliolo JMLusivika-Nzinga CLapidus NTouvier MSzabo de Edelenyi FAncel PYEsseddik YLydie NBlanche HMeyer LRouquette ACarrat FDeleuze JFCharles MAfalseAntibody status and cumulative incidence of SARS-CoV-2 infection among adults in three regions of France following the first lockdown and associated risk factors: a multicohort study.<h4>Background</h4>We aimed to estimate the seropositivity to anti-SARS-CoV-2 antibodies in May-June 2020 after the first lockdown period in adults living in three regions in France and to identify the associated risk factors.<h4>Methods</h4>Between 4 May 2020 and 23 June 2020, 16 000 participants in a survey on COVID-19 from an existing consortium of three general adult population cohorts living in the Ile-de-France (IDF) or Grand Est (GE) (two regions with high rate of COVID-19) or in the Nouvelle-Aquitaine (NA) (with a low rate) were randomly selected to take a dried-blood spot for anti-SARS-CoV-2 antibodies assessment with three different serological methods (ClinicalTrial Identifier #NCT04392388). The primary outcome was a positive anti-SARS-CoV-2 ELISA IgG result against the spike pr2021-01-01T00:00:00Z2021 Nov2026-07-16T09:09:20.261Z2022-02-11T16:10:12.159ZS-EPMC83449483429314110.1093/ije/dyab110