SuperbugsHydrogen peroxide vapor kill superbugs dead

Infection control experts at the Johns Hopkins Hospital have found that a combination of robot-like devices that disperse a bleaching agent into the air and then detoxify the disinfecting chemical are highly effective at killing and preventing the spread of multiple-drug-resistant bacteria, or so-called hospital superbugs.

A study report on the use of hydrogen peroxide vaporizers — first deployed in several Singapore hospitals during the 2002 outbreak of severe acute respiratory syndrome, or SARS, and later stocked by several U.S. government agencies in case of an anthrax attack — was published 1 January in the journal Clinical Infectious Diseases.

A Johns Hopkins University release reports that in the study, the Johns Hopkins team placed the devices in single hospital rooms after routine cleaning to disperse a thin film of the bleaching hydrogen peroxide across all exposed hospital equipment surfaces, as well as on room floors and walls. Results showed that the enhanced cleaning reduced by 64 percent the number of patients who later became contaminated with any of the most common drug-resistant organisms. Moreover, researchers found that protection from infection was conferred on patients regardless of whether the previous room occupant was infected with drug-resistant bacteria or not.

“Hydrogen peroxide vapor, as spread around patients’ rooms by these devices, represents a major technological advance in preventing the spread of dangerous bacteria inside hospitals and, especially, from one patient occupant to the next, even though sick patients were never in the same room at the same time,” says infectious disease specialist and study senior investigator Trish Perl, M.D., M.Sc.

Of special note, researchers say, was that enhanced cleaning with the vapor reduced by 80 percent a patient’s chances of becoming colonized by a particularly aggressive and hard-to-treat bacterium, vancomycin-resistant enterococci (VRE).

In what is believed to be the first head-to-head comparison between traditional hand-cleaning and mopping with bleaching agents and robotic vaporizers, researchers routinely tested patients and their surroundings not only for VRE, but also for the more common methicillin-resistant Staphylococcus aureus, or MRSA, and lesser-known bacteria, including Clostridium difficile and Acinetobacter baumannii.

The release notes that some 6,350 patient admissions to JHH were closely tracked as part of the two-and-a-half-year analysis, as patients moved into and out of 180 private hospital rooms. Almost half the rooms received enhanced cleaning with hydrogen peroxide vapor in between patients, while the rest did not. Overall, multiple-drug-resistant organisms were found on room surfaces in 21 percent of rooms tested, but