Carbapenem-Resistant Enterobacteriaceae in Korean Elderly Nursing Hospitals in 2023: Prevalence, Mortality, and Resistance Patterns

Infections caused by Carbapenem-Resistant Enterobacteriaceae (CRE) represent a critical threat in healthcare settings owing to limited therapeutic options and high associated mortality. However, the epidemiological patterns and dynamics of CRE transmission in geriatric care hospitals remain poorly characterized. We elucidated the monthly incidence, bacterial species distribution, resistance genotypes, and patient demographics of CRE infections among inpatients at a senior care hospital in Gyeonggi-do, South Korea, between January and December 2023. In this retrospective cohort study, we analyzed 41,374 culture tests performed weekly throughout 2023 on 2,500 patients hospitalized at a specialized infectious disease geriatric care hospital in Korea. The distribution and prevalence of CRE infections were categorized according to months, sample type, sex, and age. In total, 4,636 CRE cases (1,913 men and 2,723 women) were detected, a majority of which (3,962) were diagnosed from rectal swab samples, with Klebsiella pneumoniae accounting for the highest number of cases (3,606). The most affected age group was < 70 years (3,336 cases). The peak months for CRE detection were August and November, whereas the highest number of deaths was recorded in December, indicating an increase throughout the year. A pre-emptive microbiological culture test was conducted on 2,500 inpatients in 2023, with a detection rate of 11.2% from 41,374 tests. These findings indicate that continuous monitoring and robust prevention strategies are essential for controlling the spread of CRE and protecting vulnerable inpatient populations. Our findings highlight the efficacy of pre-emptive microbiological culture tests, and show that enhanced monitoring and stringent isolation practices can prevent CRE infections in medical settings.