Study of the Innate Immune Response to the Acute Phase of Human Leptospirosis - IMMUNOLEPTO

Inclusion Criteria: * Age ≥ 4 years; * Weight ≥ 11 kg; * with ongoing symptoms compatible with a clinical diagnosis of leptospirosis. * AND having a diagnosis of leptospirosis confirmed according to standard care procedures: preferably by Polymerase Chain Reaction (PCR) (blood or urine) or, failing that, serology indicating a recent infection (positive Immunoglobulin M (IgM) or Microscopic Agglutination Test (MAT) technique with titer \>1/400 for a pathogenic serogroup) * AND affiliated to a Social Security scheme Exclusion Criteria: * Refusal of participation by the patient or his entourage if the patient is physically unable to give his opinion (coma, resuscitation, etc.). * Not affiliated with social security * Immunosuppression that may interfere with the interpretation of the results: chemotherapy in progress, immunosuppressants in progress for organ transplantation or autoimmune disease * Patient under legal protection (Guardianship, Curators)