Long term impact of the SARS-CoV2 pandemic on the acquisition rate of extended-spectrum beta-lactamase-producing Enterobacteriaceae in a medical intensive care unit.

Background: The COVID-19 pandemic led to major changes in patient care, with enhanced hygiene possibly reducing MDR bacteria transmission, while increased nursing workload and antibiotic use may have raised the risk of MDR acquisition.

Methods: A 5-year retrospective study compared ESBL-E acquisition rates in a single ICU between the pre-COVID and COVID periods.

Results: Between January 2018 and December 2022, 1736 ICU patients (mean age 64 [49-79] years) were included. Admission severity was similar across periods, but ICU stay was longer during COVID (19±19 vs. 14±13 days, p<0.001), with more patients requiring mechanical ventilation (81% vs. 73%, p<0.001) for a longer duration (17±19 vs. 10±10 days, p<0.001). ESBL-E acquisition increased by 57.3% during the COVID period (14% [CI95 11.6-16.7] vs. 8.9% [CI95 7.1-11.0], p=0.001), while admission carriage rates were similar (6% vs. 8%, p=0.57). In multivariate analysis, ICU stay duration (OR=1.01 per day), mechanical ventilation >10 days, ESBL-E prevalence, and hemodialysis were associated with acquisition; noninvasive ventilation was protective.

Conclusions: In our ICU, ESBL-E acquisition increased during the COVID period. Multivariate analysis linked it to length of stay, ESBL-E prevalence, mechanical ventilation >10 days, and hemodialysis. Further studies are needed to assess post-COVID trends.