This is a prospective observational cohort study that will define the prevalence and incidence of CA-SARS-Cov2 infection using serological and PCR tests in a group of subjects during deconfinement. The team wishes to include approximately 1000 subjects in this study.

The health crisis through containment has also created unprecedented environmental conditions with the very clear decrease in economic activities and a consequent decrease in exposure to the main air pollutants. The aim is therefore to carry out a case-control study in which each subject will be his or her own control in unexposed condition (to PM2.5, PM10, NO...) then exposed (after the recovery of economic activity and the usual levels of air pollutants) and to measure the impact of these pollutants on the immune system and epigenetic markers taking into account seasonality.

The occurrence of infectious, cardiovascular, allergic and autoimmune events will then be measured according to the immunological profiles measured at inclusion.

Inclusion Criteria:

• Any major subject, voluntary, exposed to the public from 11 May 2020 informed of the study by partner institutions (Departmental Council 06), affiliated to a social security scheme,

Exclusion Criteria:

• Subject protected by law under tutorship or guardianship, or who cannot participate in a clinical study under the terms of Article L. 1121-16 of the French Public Health Code