Study: UV-C light effectively disinfects non-sterile, high-touch surfaces

Editor's Note

Although many studies have focused on infection transmission within the operating room, authors of research published in the March issue of the Journal of Infection Control focused their study of UV-C light disinfection on non-sterile hubs of patient care—in this case, high-touch surfaces within an academic endoscopy unit. Findings show bioburden was reduced by an average of more than 91% at high-touch surfaces and within procedure rooms.

Approximately 1 in 31 hospitalized patients suffer a hospital-acquired infection (HAI) annually, the authors note, mostly due to medical devices such as catheters and ventilators. However, shared equipment—pens, counters, and so forth—has also been implicated in pathogen transmission. Thus, nonsterile hubs of patient care could serve as sites of “silent” HAI transmission.

For this study, conducted in an inpatient/outpatient endoscopy unit at a tertiary care academic medial center, researchers tested automated cycles with UV-C lights on the top 3 high-touch surfaces identified by monitoring with motion sensors: anesthesiologist, endoscospist, and nursing computer keyboards. The lights were programmed turn on 90 seconds after the last user input and remain on for 18-minute cycles (a time based on previous analysis of UV-C inactivating clostridium difficile spores). Bioburden was swabbed throughout the study (although only for colony counting, not identifying or culturing specific bacteria).   

Across all endoscopy rooms analyzed for baseline bioburden, anesthesiologist keyboards showed an average of 50 colony forming units (CFU), with 80% of samples exhibiting detectable bacterial contamination. Endscopist keyboards showed an average of 78.99 CFU, with 88.9% of samples exhibiting detectable contamination. For nursing keyboards, the figures were 41.67 CFU and 83.3% of collected samples.

“Nonsterile hubs of patient care could serve as sites of “silent” HAI transmission,” the researchers write. “We have identified high-touch surfaces within an endoscopy unit that have a high bioburden of bacterial contamination and demonstrated that the installation of passive, automated UV-C light disinfection devices can reduce bioburden significantly, possibly mitigating HAI transmission between patients.”