SAPRIS-SERO is a study to estimate the seroprevalence of SARS-CoV-2 infection in the epidemiological cohorts Constances, E3-E4N, NutriNet-Santé and Elfe-Epipage2 in France

Keywords: SARS-CoV2; cohort; containment; serology; prevention

Some results:

Figure 1. Proportion of participants with possible COVID-19 and a positive ELISA-S serological result according to the date of the onset of symptoms
Figure 2. Risk factors of positive ELISA-S by French region

Description of the Study:

  • Title: Seroprevalence of SARS-CoV-2 among adults in three regions of France following the lockdown and associated risk factors: a multicohort study.
  • Principal Investigator:  Fabrice Carrat.
  • Co-Investigators: Marie Zins, Gianluca Severi, Mathilde Touvier, Marie-Aline Charles and Pierre-Yves Ancel.
  • Study Population: 14,600 participants interviewed during the first confinement of the Constances, E3N-E4N, Elfe, Epipage and NutriNet-Santé cohorts.
  • Study Type: Prospective observational study.
  • Design: Firstly, participants were questioned on several occasions about their conditions of confinement, their possible symptoms and medical follow-up. Secondly, participants in a COVID-19 survey of an existing consortium of three general adult population cohorts living in Ile-de-France (IDF) or Grand Est (GE) – two regions with a high rate of COVID-19 – or in Nouvelle-Aquitaine (NA) – with a low rate – were asked to have a dried-blood spot (DBS) to assess anti-SARS-CoV-2 antibodies.
  • Methods:
    – The primary outcome was a positive anti-SARS-CoV-2 IgG ELISA result against the virus spike protein (S-ELISA).
    – Secondary outcomes were a positive IgG ELISA result against nucleocapsid protein (ELISA-NP), anti-SARS-CoV-2 neutralising antibody values ≥40 (SN), and predicted positivity obtained from a multiple imputation (MI) model.
    – Prevalence estimates were adjusted using sampling weights and post-stratification methods.

Objectives of the Study:

Principal Objective: To estimate the seroprevalence of SARS-CoV-2 infection, between May and June 2020 after confinement, in adults living in three regions of France and to identify associated risk factors.

More about this Study:

Scientific Context: At the end of February 2020, the idea arose to ask participants of the E3N-E4N epidemiological study to advance research on the new coronavirus (SARS-CoV-2). These volunteers have been helping health research for the past 30 years to a large extent by regularly answering questionnaires about their health and lifestyle and by giving biological samples (blood, saliva). Used to contributing to research on cancer and major chronic diseases, now it is time to help understand a new infectious disease to which they are called.

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