The Effect of Leukocyte Dna mEthylation and micRoBIOME Diversity on Host Defense Mechanisms During Community-acquired Pneumonia (ELDER-BIOME)

Inclusion Criteria: * Clinical suspicion of a new episode of acute respiratory tract infection * Primary reason for presentation is clinical suspicion of a new episode of acute respiratory infection; admission to the hospital is NOT a requirement * Evident new or progressive infiltrate, consolidation, cavitation, or pleural effusion on the chest X ray or CT scan made for diagnostic (non-research) purposes * Onset of the following symptoms within the last 7 days: * At least one respiratory symptom (cough, sore throat, runny or congested nose, dyspnea) * At least one systemic symptom (fever, headache, muscle ache, sweats or chills or tiredness). Exclusion Criteria: * Patient lacks capacity to provide informed consent * No informed consent is provided by patient * Patient has been transferred from another hospital * Patient is enrolled in an interventional clinical study of an anti-infective or immunomodulatory therapy * Patient has received any type of oral or systemic antibiotics for more than 48 hours prior to hospital presentation.