Risk assessment of selected bacterial infections acquired in intensive care units in Poland in the years 2019-2023-analysis with the application of the standardized infection ratio.

BACKGROUND: Socioeconomic development as well as medical progress has led to a reduction in infectious diseases. The currently observed reappearance of alarming pathogens and the increasing microbial resistance indicate alarming infectious disease resurgence. OBJECTIVE: The aim of this study was to evaluate the risk of infections with methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus faecalis and Enterococcus faecium (VRE), Klebsiella spp. producing extended-spectrum β-lactamases (ESBL), and Klebsiella pneumoniae producing metallo-β-lactamases (MBL) as well as New Delhi metallo-β-lactamase (NDM) in intensive care units (ICUs) in Poland in the years 2020-2023 in comparison to the baseline year of 2019, using the standardized infection ratio (SIR). METHODS: The research material comprised aggregated annual epidemiological data gathered by the Chief Sanitary Inspectorate, which covered all ICUs in Poland in the period from 2019 to 2023, including the number of infections diagnosed after 72 h of hospitalization and the number of ICU person-days. SIR was subjected to an analysis relative to the reference year 2019, and the incidence rate was compared between years and voivodeships with application of the Kruskal-Wallis test and post hoc analyses. RESULTS: In the case of MRSA, elevated SIR values were observed in the Lublin, Subcarpathian, and Silesian Voivodeships. In the Lodz Voivodeship, compared to 2019, a sustained risk reduction was detected. The multiple increase in the risk of E. faecalis VRE infections in the Lublin Voivodeship was particularly alarming, with SIR values exceeding the reference level several times between 2020 and 2023. With respect to E. faecium VRE, the highest and long-term exceedances were noted in the Holy Cross Voivodeship. The most dynamic growth concerned MBL/NDM-producing K. pneumoniae on account of the fact that in the Lower Silesian and Silesian Voivodeships, SIR values reached levels several dozen times higher than those noted in the baseline year. The incidence analysis confirmed material differences between voivodeships, albeit the differences between years were significant primarily in the case of MBL/NDM-producing K. pneumoniae. CONCLUSIONS: In the years 2020-2023, significant changes in the risk of infection were observed in ICUs in Poland as well as clear regional variations compared to 2019. The largest and most alarming increases concerned infections caused by MBL/NDM-producing K. pneumoniae, indicating the need to strengthen epidemiological surveillance and infection control measures.