Inclusion Criteria:  Adult patients (aged ≥18 years) Patients who need non-invasive ventilation (NIV or CPAP) or invasive ventilation (intubation)  Exclusion Criteria:  Previous diagnosis of severe liver or kidney failure. Patients with Human Immunodeficiency Virus (HIV) infection. Patients with previous hematological diseases (Leukemia) that condition alterations in blood counts. Consumption of treatments with any type of immunosuppressants prior to admission that conditions low lymphocytes. Patients with bone marrow depression.