Outbreak of multidrug-resistant Acinetobacter baumannii in a Belgian university hospital after transfer of patients from Greece.

Multidrug-resistant (MDR) Acinetobacter baumannii are emerging as important
nosocomial pathogens. These organisms have a capacity for long-term survival in
the hospital environment. The purpose of this study was to describe the course
and control of an outbreak with MDR A. baumannii in a Belgian university hospital
after transfer of two trauma patients from Greece. Wounds in both patients were
colonised with MDR A. baumannii. Over an 11 month period from September 2004 to
July 2005, carbapenem-non-susceptible A. baumannii (producing
carbapenem-hydrolysing oxacillinase OXA-58) were isolated from 28 patients,
despite early implementation of contact precautions. MDR A. baumannii was
detected in routine clinical diagnostic samples from 26 patients and in screening
specimens from an additional two patients. Twenty patients (71.4%) were colonised
or infected during their stay in intensive care. Twenty-four (85.7%) respiratory
samples were positive for MDR A. baumannii. Careful review of all procedures
related to the respiratory tract did not identify a common route of transmission.
Outbreak control required multiple interventions, including contact isolation of
colonised and infected patients, monitoring the practice of personnel, screening
of asymptomatic patients, use of isolation rooms and enhanced environmental
disinfection. Introduction of single-use ventilator circuits was considered but
the outbreak was controlled before implementation.