Control of multidrug-resistant Acinetobacter baumannii in Hong Kong: Role of environmental surveillance in communal areas after a hospital outbreak

Am J Infect Control. 2018 Jan;46(1):60-66. doi: 10.1016/j.ajic.2017.07.010. Epub 2017 Sep 8.

Abstract

Background: Environmental reservoir is an important source of multidrug-resistant Acinetobacter baumannii (MRAB) outbreaks. The role of postoutbreak environmental surveillance for guiding sustained infection control effort has not been examined.

Methods: Enhanced environmental disinfection and regular environmental surveillance of ward communal areas after an outbreak were performed in a university-affiliated hospital. To assess the usefulness of environmental culture in predicting patients with MRAB, weekly surveillance of communal areas was continued for 3 months after the outbreak in intervention wards. The incidence of MRAB in intervention and nonintervention wards (control) was compared, whereas the other infection control measures remained identical.

Results: Postoutbreak weekly surveillance of communal areas showed that identification of newly diagnosed MRAB patients was significantly correlated with preceding environmental contamination with MRAB (P = .001). The incidence of nosocomial MRAB infection was significantly lower in the intervention compared with nonintervention wards (0.55 vs 2.28 per 1,000 patient days, respectively; P = .04). All MRAB isolated from the environmental and patients' samples belonged to multilocus sequence typing ST457 and were blaOXA23-like positive.

Conclusions: Environmental surveillance may serve as a surrogate marker for the presence of MRAB carriers. Implementation of timely infection control measures should be guided by environmental culture for MRAB to minimize the risk of MRAB outbreak.

Keywords: Environmental surveillance; Multidrug-resistant Acinetobacter baumannii; Outbreak.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acinetobacter Infections / epidemiology
  • Acinetobacter Infections / microbiology*
  • Acinetobacter Infections / prevention & control
  • Acinetobacter baumannii / drug effects*
  • Adult
  • Aged
  • Aged, 80 and over
  • Anti-Bacterial Agents / pharmacology*
  • Disease Outbreaks*
  • Drug Resistance, Multiple, Bacterial*
  • Environmental Microbiology*
  • Female
  • Hong Kong / epidemiology
  • Hospitals
  • Humans
  • Male
  • Middle Aged
  • Risk Factors

Substances

  • Anti-Bacterial Agents