Baseline assessment comprises sociodemographic, anamnestic, family history, and live style information. Upon enrollment, Pneumonia Severity Index (PSI) and CURB-65 are determined. For the day of enrollment and up to six subsequent study days routine laboratory and clinical observations and information on therapy are documented as well as data for determining the Sequential Organ Failure Assessment (SOFA) score, Systemic Inflammatory Response Syndrome (SIRS) status, and organ dysfunction. Starting with enrollment, up to six consecutive sets of biomaterials are collected comprising serum, plasma, and materials for extraction of RNA. Blood for extraction of DNA is collected once.