Abstract
Sixty-six patients with laboratory-confirmed severe acute respiratory syndrome coronavirus 2 and pneumonia on chest computer tomography were prospectively recruited. A combined respiratory swab for polymerase chain reaction (PCR), urine sample for pneumococcal and Legionella antigen, and sputum or endotracheal aspirate were collected. Urinary antigen and blood culture tests were negative in all cases as well as the PCR tests for other respiratory viruses and atypical bacterial pathogens. In total, 5 patients (7.5%) had co-infection. By PCR a high prevalence of colonization with bacterial pathogens was found. In conclusion, co-infection is rare in coronavirus disease 2019 patients, and additional examination to identify other pathogens should be performed only in selected cases.