The PACAAP study aims to report the seroprevalence of SARS-CoV-2 IgG antibodies among HCWs testing during the massive campaign screening set up in France by French ministry of Health and national authorities in four hospital of the Alpine region.

In France during the first wave of the pandemic, 30,230 symptomatic healthcare workers had been reported positive. Yet, the prevalence of the infection in French healthcare workers remains unknown as it mostly reflect symptomatic infections.

Also, the prevalence of infection was reported being higher in male healthcare workers, and in those having patients' facing roles. However, the impact of the level of exposure to SARS-CoV-2, the use of personal protective equipment and hospital organization to prevent infection and spread remains unclear.

Our study aims to report the seroprevalence of SARS-CoV-2 infection among French healthcare workers after the first wave of the pandemic. It also aims to explore the impact of the type of occupations and the level of exposure to the viruses on the seroprevalence of infection.

Inclusion Criteria:

• Hospital staff employee
• Employed in one of the participating centers
• Volunteers to perform SARS-CoV-2 serology
• Permanent or occasional staff (temporary workers, short contracts)
• Caregivers or not (medical, paramedical, administrative, technical staff)

Exclusion Criteria:

• Staff who are not working at a participating center while participating in the study
• Person under guardianship or curatorship
• Opposition to data collection

The study will be proposed to all the staff of participating hospitals, who have been tested for SARS-CoV-2 (serology) and who have not objected to the use of their health data.