Infectious disease specialist and study senior investigator Dr. Trish Perl said some 6,350 patient admissions to The Johns Hopkins University Hospital in Baltimore were closely tracked as part of the two-and-a-half-year analysis, as patients moved into and out of 180 private hospital rooms.
The paired robot-like devices, each about the size of a washing machine and weighing nearly 60 pounds, are brought into a room after it has been cleaned.
The room is sealed and the larger of the two devices disperses hydrogen peroxide into the room, leaving a very tiny, almost invisible layer on all exposed surfaces, including keyboards and monitors, as well as tables and chairs.
Hydrogen peroxide can be toxic to humans if ingested or corrosive if left on the skin for too long. The second, smaller device is activated to break down the bleach into its component water and oxygen parts. The combined operation takes the devices about an hour and a half to complete, Perl said.
The study, published in the journal Clinical Infectious Diseases, found the enhanced cleaning reduced by 64 percent the number of patients who later became contaminated with any of the most common drug-resistant organisms.
"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," Perl said.