Bacterial secondary infections were commonly reported in viral respiratory tract infections. However, it is not clear whether there is a difference in the infection rates during the hospitalization in intensive care unit (ICU) caused by COVID-19. The aim of this study was to evaluate the secondary infections in long-term hospitalized patients in the ICU due to COVID-19 and whether COVID-19 increases the tendency to secondary infection in ICU patients.

This is a retrospective case-control study. It was conducted in a tertiary care hospital including 34-bed COVID-19 ICU and 20-bed non–COVID-19 ICU. Adult patients in the ICU hospitalized for ≥10 days were included the study. The results of microbiological cultures of blood, urine, and respiratory samples were evaluated in terms of infections during their hospitalization.

The study group consisted of 51 patients with COVID-19 and the control group consisted of 57 non–COVID-19 patients. There was no significant difference between 2 groups in terms of distribution and frequency of agents isolated from blood culture. The frequency of isolation of Enterobacterales members in urine cultures and nonfermenting bacteria in respiratory samples were significantly higher in non–COVID-19 patients compared with COVID-19 patients (P < 0.05).

This study revealed that there was no difference among the patients with and without COVID-19 in ICU for the secondary infections when the ICU stay was prolonged. We think that prolonged hospitalization, urinary catheterization, and mechanical ventilation are more important risk factors for secondary infections in ICUs and COVID-19 does not occur an additional risk factor in prolonged ICU stay.