Active surveillance of vancomycin-resistant Enterococcus faecium after its outbreak at patient admission.

Vancomycin-resistant Enterococcus faecium (VRE) causes high mortality and has been increasingly detected worldwide in recent years; however, its screening effectiveness at admission remains controversial. We aimed to evaluate the effectiveness of active surveillance culture (ASC) for VRE at admission following a nosocomial outbreak. A VRE outbreak occurred at Shizuoka General Hospital in 2022, and ASC for VRE was performed upon admission for high-risk cases after the outbreak between January 2023 and December 2023. ASC was conducted in 2941 patients at admission, with 13 of them testing positive (0.44 %). The highest cumulative incidence and odds ratios (ORs) of ASC positivity at admission were detected among patients with a VRE detection history (5/18, cumulative incidence: 27.78 %, OR: 140.14, p < 0.001). The second highest cumulative incidence and OR occurred in patients hospitalized within the past 3 months in VRE-endemic areas (5/85, cumulative incidence: 5.88 %, OR: 22.25, p < 0.001). Hospitalization at SGH within the past 3 months showed a low cumulative incidence and OR (1/2,034, cumulative incidence: 0.05 %, OR: 0.037, p = 0.002). Among patients with urinary catheters, three of 132 patients tested ASC-positive (cumulative incidence: 2.27 %, OR: 6.51, p = 0.05), and six out of 403 individuals requiring toilet assistance were ASC-positive (cumulative incidence: 1.49 %, OR: 5.46, p = 0.02). None of the ASC-positive patients had a history of nursing home admissions or diarrhea. Our findings suggest that following a VRE nosocomial outbreak, ASC at admission should be prioritized for patients with a history of VRE detection or recent hospitalization in VRE-endemic areas.