COMPArative Study of the Consequence on innaTe Immune Response du to Bacterial or Viral Infection in Patients Admitted to Intensive Care Unit

Inclusion Criteria: * Bacterial infection: * Adult patient hospitalized for less than 24 hours in ICU for community documented sepsis * Vasopressor support * SOFA score \> 4 * Viral infection: * Adult patient hospitalized for less than 24 hours in ICU for confirmed viral acute infection. * High flow oxygen, non-invasive or invasive ventilation since less than 24 hours * Moderate to severe ARDS with PaO2/FiO2 \< 200mmHg and a FiO2 ≥ 0.6. Exclusion Criteria: * Bacterial infection: * Antibiotics or hospitalized in ICU in the previous 3 months * Immunocompromized patient * Ongoing acute or chronic viral infection * Viral infection: * Antibiotics or hospitalized in ICU in the previous 3 months * Immunocompromized patient * Current antibiotics * Ongoing chronic viral infection.