Nosocomial infections amongst critically ill COVID-19 patients in Australia.

Purpose: To determine the frequency of nosocomial infections including hospital-acquired pneumonia (HAP) and bloodstream infection (BSI), amongst critically ill patients with COVID-19 infection in Australian ICUs and to evaluate associations with mortality and length of stay (LOS).

Methods: The effect of nosocomial infections on hospital mortality was evaluated using hierarchical logistic regression models to adjust for illness severity and mechanical ventilation.

Results: There were 490 patients admitted to 55 ICUs during the study period. Adjusted odds ratio (OR) for hospital mortality was 1.61 (95% confidence interval (CI) 0.61-4.27,  = 0.3) when considering BSI, and 1.76 (95% CI 0.73-4.21,  = 0.2) for HAP. The average adjusted ICU LOS was significantly longer for patients with BSI (geometric mean 9.0 days vs 6.3 days,  = 0.04) and HAP (geometric mean 13.9 days vs 6.0 days <0.001).

Conclusion: Nosocomial infection rates amongst patients with COVID-19 were low and their development was associated with a significantly longer ICU LOS.