Elevated antibiotic resistance gene abundance of ICU healthcare workers, a multicentre, cross-sectional study

Studies suggest that the colonization of multidrug-resistant organism in the gut of healthcare workers is similar to that of healthy individuals. However, due to exposure to medical environments, is the abundance of antibiotic resistance genes (ARG) in the gut of ICU healthcare workers higher than that of healthy individuals? Prospective, multicentre, cross-sectional study. Eight medical centers in China, recruiting from January 2024 to February 2024. 303 Healthy people (201 ICU healthcare workers and 103 healthy controls) were screened and 290 Healthy people (191 ICU healthcare workers and 99 healthy controls) were included in analysis. Fecal samples were collected and subjected to metagenomic sequencing. We compared the total ARG abundance, ARG diversity, and gut microbiome composition between the two groups. After adjusting for age, sex, and body mass index, ICU healthcare workers exhibited a significantly higher total ARG abundance compared to healthy controls (fold change = 1.22, 95% CI: 1.12–1.34, p < 0.001). The β-diversity of ARG between the two groups differed significantly (p = 0.001). No significant linear or nonlinear relationship was observed between the duration of ICU occupational exposure and ARG abundance (p for overall = 0.96, p for nonlinear = 0.84). In this prospective, multicenter study, we found that ICU healthcare workers exhibit significantly higher gut ARGs abundance compared to healthy controls. Meanwhile, ICU healthcare workers, including physicians, nurses, and nursing assistants, have a different composition of gut ARGs compared to healthy individuals. Trial registration: NCT06228248.