TOPLINE:

Installing germicidal ultraviolet (UV) air purification devices that run 24/7 in an endoscopy room alongside standard cleaning protocols substantially reduced bacterial colony-forming units (CFU) of airborne and surface bacteria and decreased levels of particulate matter.

METHODOLOGY:

• Many aerosol-generating procedures are conducted in endoscopy rooms, where the air typically is cleaned by standard heating, ventilation, and air conditioning (HVAC) systems and the occasional use of UV light, and surfaces receive routine cleaning. This study evaluated whether installing a UV-based air purification system could further reduce contamination.
• Researchers at Stanford Hospital had four units of the UV air purification system installed in one endoscopy room (the mitigation room) and compared findings from that room with a control room without the units. Both rooms were used for similar endoscopic procedures, including upper endoscopies and colonoscopies; had properly functioning HVAC systems; and were cleaned according to standard protocols.
• The air purification system units operate 24/7 and feature ceiling-mounted light boxes for room lighting and germicidal UV chambers. The units continuously draw room air through internal filtration and use UV exposure to reduce the burden of airborne bacteria.
• Airborne and settled surface bacterial samples were collected, and particle counts of 0.3 and 2.5 µm in size were measured in both rooms before and several weeks after the units were installed in the mitigation room.

TAKEAWAY:

• Airborne bacterial counts in the mitigation room fell from 130.8 CFU per m³ before installation of the UV air purification units to 27.2 CFU per m³after installation, reflecting a 79% reduction (P < .0001). There was no significant reduction in control room, which had a similar bacterial load when samples were first collected.
• The surface bacterial load in the mitigation room dropped 44%, from 10.2 to 5.7 CFUs per 25-cm²area (P = .016). It increased in the control room, but the difference didn’t reach statistical significance.
• Particle counts per liter of air in the mitigation room fell by 47% for particles sized 0.3 µm and by 75% for those sized 2.5 µm (both P < .01), while particle counts for both sizes increased significantly in the control room over the same period.

IN PRACTICE:

"By demonstrating significant reductions in airborne bacteria, surface bacteria, and particulate matter, this research supports the integration of in-room supplemental air treatment systems into infection control strategies and indoor air quality management," the authors wrote. "Given the relative simplicity of design and implementation of these wall-mounted devices, we anticipate that these findings may also be applicable to other environments in which endoscopic (and potentially other) procedures are performed, including intensive care units, operating rooms, and outpatient clinics."

SOURCE:

This study, led by Monique T. Barakat, MD, PhD, Stanford University School of Medicine, California, was published online in Digestive Diseases and Sciences.

LIMITATIONS: 

The high cost of identifying specific microbes prevented researchers from performing such studies, which limits the clinical interpretability of the results. This study included only two endoscopy rooms due to financial constraints, which may limit generalizability.

DISCLOSURES:

This study was funded by UV Partners Inc., which manufactures the air purification units used in the research. The authors declared having no competing interests.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.