Nosocomial infections rate in an ICU COVID population compared to an ICU population admitted in the pre COVID era

The outcome of critically ill COVID-19 patients is well described, it is suggested that patients admitted to ICU had more exposure to antibiotics and a higher rate of nosocomial infections during the pandemic. <bold>Objective:</bold> to test this hypothesis we compared the overall nosocomial infection rate in 3 sites : sterile body fluids, respiratory tract and urinary tract in the period just before COVID and during COVID period. <bold>Design:</bold> All patients admitted to our adult ICUs between 2017 and 2019 for > 24h were considered the control population and all COVID patients admitted for respiratory failure were the studied population up to the end of 2021. <bold>Outcomes and measures:</bold> In the pre-COVID period 1456 patients were admitted to ICUs, 181 developed a nosocomial infection (12,4%). During COVID 164 patients were admitted for respiratory failure, 64 acquired a nosocomial infection (42,1%). Sterile site infections were more common during the COVID period compared to the control period 29,3% vs 6,1 % (p < 0,001), rate for nosocomial respiratory tract infections was 27,4% in COVID patients vs 6,9% in the pre COVID patients (p < 0,001), urinary tract infection CAUTI related or not were almost double in the COVID period 5,5% vs 2,3% (p=0,028). Length of stay in the ICU during COVID compared to pre-COVID was 29,9 days vs 22,2 days (p = 0,015), 28 and 90-days mortality were not significantly different between the 2 groups. MDR were more common during the pre COVID period (25,2% vs 10,5%); while wild type stenotrophomonas was more common during COVID (22,8% vs 8,1%). <bold>Conclusion:</bold> Nosocomial infections were more common during COVID period compared to pre-COVID.