Interhospital Transmission of Vancomycin-resistant Enterococcus Faecium in Aomori, Japan

Abstract

A series of vancomycin-resistant Enterococcus faecium (VREf) outbreaks caused by clonal propagation due to inter-hospital transmission occurred in six general hospitals in Aomori prefecture, Japan. This was the first multi-jurisdictional outbreak of VREf sequence type 1421 in Japan. It took almost three years for VREf prevalence to return to pre-outbreak levels. The duration and size of outbreaks differed between hospitals according to the countermeasures available at each hospital. Prompt and strong countermeasures including patient isolation and repetitive screening of all inpatients were required to control the outbreaks. In addition to strict infection control measures, continuous monitoring of VREf prevalence in local medical regions and smooth and immediate communication among hospitals are required to prevent VREf outbreaks.