Cleaning protocols ineffective against <i>A. baumannii</i>

Persisten room contamination can serve as a reservoir for disease transmission.

Ridding hospitals of multidrug-resistant Acinetobacter baumannii may require new cleaning protocols, according to a research study published in the December 2012 issue of the American Journal of Infection Control.

The study, conducted by researchers from the University of Maryland, found that more than half the rooms positive for the A. baumannii bacteria prior to cleaning remained contaminated after terminal cleaning had been performed.

The research team collected 487 cultures from 32 hospital rooms occupied by just-discharged patients with a known history of A. baumannii before cleaning. After cleaning, eight rooms (25 percent) and 12 sites (5.5 percent) still tested positive for the pathogen. Sites with post-cleaning contamination included the floor (12.5 percent), call button (10 percent), door handle (9.4 percent), bedside table (7.4 percent) and supply cart (3.8 percent).

"Persistent room contamination serves as a potential reservoir for transmission and colonization of future room occupants," the authors note in the study. "Current cleaning techniques in terms of products used or thoroughness of cleaning may not be adequate in the decontamination of this pathogen."

A. baumannii has become increasingly prevalent in health care facilities and is resistant to most antibiotics. Infections from this pathogen primarily occur in very ill, wounded or immunocompromised patients. The germ can remain on wet or dry surfaces for longer than most other organisms, making it harder to eradicate.

"This study shows how difficult it is to ensure the removal of particularly resistant organisms from the environment even upon thorough discharge cleaning," says Anthony D. Harris, M.D., MPH, lead study author and professor of epidemiology and public health at the University of Maryland School of Medicine. "With new, innovative means of monitoring cleaning processes that we have incorporated since the study, coupled with other infection control efforts, we are seeing lower rates of A. baumannii at our hospital."