TY - JOUR
T1 - Antibody status and cumulative incidence of SARS-CoV-2 infection among adults in three regions of France following the first lockdown and associated risk factors
T2 - A multicohort study
AU - Carrat, Fabrice
AU - De Lamballerie, Xavier
AU - Rahib, Delphine
AU - Blanché, Hélène
AU - Lapidus, Nathanael
AU - Artaud, Fanny
AU - Kab, Sofiane
AU - Renuy, Adeline
AU - Szabo De Edelenyi, Fabien
AU - Meyer, Laurence
AU - Lydié, Nathalie
AU - Charles, Marie Aline
AU - Ancel, Pierre Yves
AU - Jusot, Florence
AU - Rouquette, Alexandra
AU - Priet, Stéphane
AU - Villarroel, Paola Mariela Saba
AU - Fourié, Toscane
AU - Lusivika-Nzinga, Clovis
AU - Nicol, Jérôme
AU - Legot, Stephane
AU - Druesne-Pecollo, Nathalie
AU - Esseddik, Younes
AU - Lai, Cindy
AU - Gagliolo, Jean Marie
AU - Deleuze, Jean François
AU - Bajos, Nathalie
AU - Severi, Gianluca
AU - Touvier, Mathilde
AU - Zins, Marie
N1 - Publisher Copyright:
© 2021 The Author(s) 2021; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.
PY - 2021/10/1
Y1 - 2021/10/1
N2 - Background: 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. Methods: 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 protein of the virus (ELISA-S). Estimates were adjusted using sampling weights and post-stratification methods. Multiple imputation was used to infer the cumulative incidence of SARS-CoV-2 infection with adjustments for imperfect tests accuracies. Results: The analysis included 14 628 participants, 983 with a positive ELISA-S. The weighted estimates of seropositivity and cumulative incidence were 10.0% [95% confidence interval (CI): 9.1%, 10.9%] and 11.4% (95% CI: 10.1%, 12.8%) in IDF, 9.0% (95% CI: 7.7%, 10.2%) and 9.8% (95% CI: 8.1%, 11.8%) in GE and 3.1% (95% CI: 2.4%, 3.7%) and 2.9% (95% CI: 2.1%, 3.8%) in NA, respectively. Seropositivity was higher in younger participants [odds ratio (OR) = 1.84 (95% CI: 1.79, 6.09) in <40 vs 50-60 years old and OR = 0.56 (95% CI: 0.42, 0.74) in ≥70 vs 50-60 years old)] and when at least one child or adolescent lived in the same household [OR = 1.30 (95% CI: 1.11, 1.53)] and was lower in smokers compared with non-smokers [OR = 0.71 (95% CI: 0.57, 0.89)]. Conclusions: Seropositivity to anti-SARS-CoV-2 antibodies in the French adult population was ≤10% after the first wave. Modifiable and non-modifiable risk factors were identified.
AB - Background: 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. Methods: 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 protein of the virus (ELISA-S). Estimates were adjusted using sampling weights and post-stratification methods. Multiple imputation was used to infer the cumulative incidence of SARS-CoV-2 infection with adjustments for imperfect tests accuracies. Results: The analysis included 14 628 participants, 983 with a positive ELISA-S. The weighted estimates of seropositivity and cumulative incidence were 10.0% [95% confidence interval (CI): 9.1%, 10.9%] and 11.4% (95% CI: 10.1%, 12.8%) in IDF, 9.0% (95% CI: 7.7%, 10.2%) and 9.8% (95% CI: 8.1%, 11.8%) in GE and 3.1% (95% CI: 2.4%, 3.7%) and 2.9% (95% CI: 2.1%, 3.8%) in NA, respectively. Seropositivity was higher in younger participants [odds ratio (OR) = 1.84 (95% CI: 1.79, 6.09) in <40 vs 50-60 years old and OR = 0.56 (95% CI: 0.42, 0.74) in ≥70 vs 50-60 years old)] and when at least one child or adolescent lived in the same household [OR = 1.30 (95% CI: 1.11, 1.53)] and was lower in smokers compared with non-smokers [OR = 0.71 (95% CI: 0.57, 0.89)]. Conclusions: Seropositivity to anti-SARS-CoV-2 antibodies in the French adult population was ≤10% after the first wave. Modifiable and non-modifiable risk factors were identified.
KW - COVID-19
KW - Cohort
KW - General population
KW - Risk factors
KW - SARS-CoV-2
KW - Seroprevalence
UR - http://www.scopus.com/inward/record.url?scp=85114599729&partnerID=8YFLogxK
U2 - 10.1093/ije/dyab110
DO - 10.1093/ije/dyab110
M3 - Article
C2 - 34293141
AN - SCOPUS:85114599729
SN - 0300-5771
VL - 50
SP - 1458
EP - 1472
JO - International Journal of Epidemiology
JF - International Journal of Epidemiology
IS - 5
ER -