Evaluation of Post-vaccination Anti-SARS-CoV-2 Serological Response in Health Care Workers With a History of COVID-19.

Study Overview
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Brief Summary
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Since the beginning of 2020, a major pandemic due to the new emerging coronavirus (SARS-CoV-2) has been spreading around the world. Today, the hope to contain this pandemic lies in the development and use of vaccines directed against this virus. Different strategies aim to maximize the early impact of vaccination in a context where few doses are available. In early January 2021, large-scale vaccination began in France, first for populations at risk of severe COVID-19, but also for healthcare workers over 50 years of age or with an underlying pathology, and then for all voluntary healthcare workers.

Detailed Description
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The question of vaccination of patients with a history of recent or late SARS-CoV-2 infection has rapidly become a major issue. Currently, French recommendations call for a single dose in the cohort that has been cured of COVID-19 for six months. In addition, the use of anti-SARS-Cov2 serology may be of interest because the presence of antibodies indicates recent or past contact with SARS-CoV-2. However, serological testing is not included in the vaccination decision strategy. The goal of the investigators is to provide data on the immune response induced by SARS-CoV-2 vaccines in a real-world setting to support this choice. Given the absence of recommendations concerning the realization of the anti-SARS-CoV-2 serology, it will be proposed to all the nursing staff of the Groupe Hospitalier Paris Saint Joseph at the time of their vaccination, a serological screening. The investigators will evaluate the dynamics of antibody production against the SARS-CoV-2 Spike protein after the first and second dose of vaccine (conventional prime-boost strategy recommended) in healthcare workers with or without a history of COVID-19.

Official Title
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Evaluation of Post-vaccination Anti-SARS-CoV-2 Serological Response in Health Care Workers With a History of COVID-19.

Conditions
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SARS CoV 2 Infection, Vaccination Reaction

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Health care workers of the Paris Saint Joseph Hospital Group whose age ≥ 18 years French-speaking Health care workers who have received the BNT162b2 mRNA vaccine (COMIRNATY, Pfizer/BioNTech). Exclusion Criteria: Health care workers under guardianship or curatorship Health care workers under court protection Health care workers who object to the use of their data for this research

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To evaluate the level of serological response after the first and second vaccine doses in health care workers with and without a history of COVID-19. | Evolution of of anti-SARS-CoV-2 antibody level at D21-28 post-first dose and at D21-28 post-second dose in healthcare workers with and without a history of COVID-19. | Day 28 |