Objective. To study spectrum of pathogens and the time to colonization of respiratory samples in patients with severe and critical COVID-19 as well as to analyze incidence of nosocomial infections and structure of prescribed antibacterial drugs.
Materials and Methods. The prospective observational study included patients aged 18 years and older with confirmed severe and critical COVID-19 from December 2021 to February 2022. During the first 48 hours and then every 2–3 days of hospitalization, a respiratory sample was collected: sputum, tracheal aspirate (if intubated), bronchoalveolar lavage (if bronchoscopy was performed) for microscopy and microbiological examination.