Article ID: JJID.2021.232
The detection of other pathogens in hospitalized coronavirus disease (COVID-19) patients are reported to be infrequent. Considering that the data from Japan is limited, we conducted an observational study including hospitalized COVID-19 patients at the National Center for Global Health and Medicine from January to September 2020. In total, 247 COVID-19 patients were studied. Rapid diagnostic tests such as immunochromatography were performed in 31 (12.6%). Filmarray Respiratory Panel was performed in 18 (7.3%) patients, and none of the tests were positive for pathogens other than severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Respiratory bacterial culture was performed in 66 (26.7%) patients, gram-positive bacteria were identified in 8 (12.1%) patients; gram-negative bacteria, 7 (10.6%) patients, and normal flora, 63 (95.5%) patients. Patients for whom culture was performed were older, more severely ill, and more likely to have radiological evidence of pneumonia on admission. Culture was more frequently performed in the early period of the epidemic than in the later period, without differences in bacterial detection rates. The proportion of viral and bacterial detections among hospitalized COVID-19 patients in tertiary care hospitals in Japan was low. A larger cohort study is necessary to evaluate the effects of each pathogen on the clinical course of COVID-19.