BACKGROUND: Elizabethkingia species are ubiquitous bacteria but uncommonly cause human infection. An outbreak of Elizabethkingia anophelis bacteremia was observed in a respiratory care center of a tertiary hospital in Taiwan from 2015 to 2018. METHODS: Clinical and environmental isolates were collected for the outbreak investigation. Pulsed-field gel electrophoresis (PFGE) and complete genome sequencing were conducted to elucidate the mechanism of transmission. FINDINGS: The three-year outbreak involved 26 patients with E. anophelis bacteremia and the incidence significantly increased during the outbreak period compared to that observed from 2010 to 2014 (p<0.05). All 26 clinical isolates during outbreak period belonged to a cluster by PFGE analysis. In contrast, the PFGE pattern was heterogeneous among comparative historical strains. Hospital tap water was highly contaminated by Elizabethkingia species (18/34, 52.9%); among that, five E. anophelis were belonged to the outbreak cluster (5/18, 27.8%). As for the inanimate surface survey, 3.4% sites (4/117) revealed positive growth of E. anophelis including 2 from feeding tubes/bags and 2 from sputum suction regulators. All four isolates were belonged to the outbreak clone. The outbreak strain has no apparent relationship to currently known E. anophelis strains worldwide through complete genome sequencing analysis. Specific infection control strategies aiming water source control and environmental disinfection were implemented subsequently and the outbreak ended since mid-2018. CONCLUSIONS: A specific E. anophelis strain was identified from a three-year outbreak. The elucidation of the mechanism of dominance and intra-hospital transmission is crucial for development of corresponsive infection control policies and outbreak control.
Date:
2021-02
Relation:
Journal of Hospital Infection. 2021 Feb;108:43-51.