VHP Used to Interrupt Acinetobacter Transmission Warrants Further Investigation

Amy Ray, MD, MPH, from the Division of Infectious Diseases and HIV Medicine at University Hospitals Case Medical Center, and colleagues, report that environmental decontamination using vaporized hydrogen peroxide (VHP) combined with comprehensive infection prevention and control measures interrupted nosocomial transmission of multidrug-resistant Acinetobacter baumannii in an LTACH.

Ray, et al. (2010) conducted a case-control study as well as before-after intervention trial in a 54-bed LTACH affiliated with a tertiary-care center in northeastern Ohio. The methods used in their investigation included antimicrobial susceptibility testing, polymerase chain reaction assay of repetitive chromosomal elements to type strains, and case-control study, as well as an intervention consisting of comprehensive infection control measures and VHP environmental decontamination.

The researchers report that 13 patients infected or colonized with MDR A. baumannii were identified from January 2008 through June 2008. By susceptibility testing, 10 (77 percent) of the 13 isolates were carbapenemresistant. MDR A. baumannii was found in wound samples, blood, sputum, and urine. Wounds were identified as a risk factor for MDR A. baumannii colonization. Ventilatorassociated pneumonia was the most common clinical syndrome caused by the pathogen, and the associated mortality was 14 percent (two of the 13 case patients died). MDR A. baumannii was found in eight of 93 environmental samples, including patient rooms and a wound care cart; environmental and clinical cultures were genetically related. Environmental cultures were negative immediately after VHP decontamination and both 24 hours and one week after VHP decontamination. Nosocomial acquisition of the pathogen in the LTACH ceased after VHP intervention. When patients colonized with MDR A. baumannii reoccupied rooms, environmental contamination recurred.

The researchers conclude that the application of this novel approach to halt the transmission of MDR A. baumannii warrants further investigation. Their research was published in Infection Control & Hospital Epidemiology.

Reference: Ray A, Perez F, Beltramini AM, Jakubowycz M, Dimick P, Jacobs MR, Roman K, Bonomo RA and Salata RA. Use of Vaporized Hydrogen Peroxide Decontamination during an Outbreak of Multidrug-Resistant Acinetobacter baumannii Infection at a Long-Term Acute Care Hospital. Infect Control Hosp Epidemiol 2010;31:12361241.