J Korean Med Sci.  2010 Jul;25(7):999-1004. 10.3346/jkms.2010.25.7.999.

Nosocomial Outbreak of Carbapenem-Resistant Acinetobacter baumannii in Intensive Care Units and Successful Outbreak Control Program

• Choi WS
• Kim SH
• Jeon EG
• Son MH
• Yoon YK
• Kim JY
• Kim MJ
• Sohn JW
• Kim MJ
• Park DW

• KMID: 1792947
• DOI: http://doi.org/10.3346/jkms.2010.25.7.999

Abstract

Acinetobacter baumannii has been increasingly reported as a significant causative organism of various nosocomial infections. Here we describe an outbreak of carbapenem-resistant A. baumannii (CRAB) in the ICUs of a Korean university hospital, along with a successful outbreak control program. From October 2007 through July 2008, CRAB was isolated from 57 ICU patients. Nineteen patients were diagnosed as being truly infected with CRAB, four of whom were presumed to have died due to CRAB infection, producing a case-fatality rate of 21.1%. In surveillance of the environment and the healthcare workers (HCWs), CRAB was isolated from 24 (17.9%) of 135 environmental samples and seven (10.9%) of 65 HCWs. The pulsed field gel electrophoresis patterns showed that the isolates from patients, HCWs, and the environment were genetically related. Control of the outbreak was achieved by enforcing contact precautions, reducing environmental contamination through massive cleaning, and use of a closed-suctioning system. By August 2008 there were no new cases of CRAB in the ICUs. This study shows that the extensive spread of CRAB can happen through HCWs and the environmental contamination, and that proper strategies including strict contact precautions, massive environmental decontamination, and a closed-suctioning system can be effective for controlling CRAB outbreaks.

Keyword

Acinetobacter baumannii; Disease Outbreaks; Infection Control

MeSH Terms

*Acinetobacter Infections/drug therapy/epidemiology/prevention & control
Acinetobacter baumannii/isolation & purification/metabolism/*pathogenicity
Adolescent
Adult
Aged
Aged, 80 and over
Anti-Bacterial Agents/*therapeutic use
Child
Child, Preschool
*Cross Infection/drug therapy/epidemiology/prevention & control
*Drug Resistance, Multiple, Bacterial
Hospitals, University
Humans
Infant
Infection Control/*methods
*Intensive Care Units
Korea/epidemiology
Male
Middle Aged
Young Adult

Figure

• 

  Fig. 1 Time course of the outbreak of colonization/infection with carbapenem-resistant A. baumannii (CRAB) in two intensive care units (ICUs). The graph displays the number of new cases of CRAB infection and colonization and the number of new patients admitted to ICUs. Infection control measures were introduced from April 2008.

• 

  Fig. 2 Banding patterns determined by pulsed field gel electrophoresis. The patterns show the genetic relatedness of the isolates of carbapanem-resistant Acinetobacter baumannii recovered from patients, health care workers, and the environment. Lanes 1-5 are from patients, 6-11 are from environmental samples, and 12 and 13 are from the hands of HCWs. Electrokaryotypes were compared and classified using the band difference criteria described in the Methods section.

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