Evaluation of a pulsed-xenon ultraviolet room disinfection device for impact on contamination levels of methicillin-resistant Staphylococcus aureus

Abstract

BackgroundHealthcare-acquired infections with methicillin-resistant Staphylococcus aureus (MRSA) are a significant cause of increased mortality, morbidity and additional health care costs in United States. Surface decontamination technologies that utilize pulsed xenon ultraviolet light (PPX-UV) may be effective at reducing microbial burden. The purpose of this study was to compare standard manual room-cleaning to PPX-UV disinfection technology for MRSA and bacterial heterotrophic plate counts (HPC) on high-touch surfaces in patient rooms.MethodsRooms vacated by patients that had a MRSA-positive polymerase chain reaction or culture during the current hospitalization and at least a 2-day stay were studied. 20 rooms were then treated according to one of two protocols: standard manual cleaning or PPX-UV. This study evaluated the reduction of MRSA and HPC taken from five high-touch surfaces in rooms vacated by MRSA-positive patients, as a function of cleaning by standard manual methods vs a PPX-UV area disinfection device.ResultsColony counts in 20 rooms (10 per arm) prior to cleaning varied by cleaning protocol: for HPC, manual (mean = 255, median = 278, q1-q3 132–304) vs PPX-UV (mean = 449, median = 365, q1-q3 332–530), and for MRSA, manual (mean = 127; median = 28.5; q1-q3 8–143) vs PPX-UV (mean = 108; median = 123; q1-q3 14–183). PPX-UV was superior to manual cleaning for MRSA (adjusted incident rate ratio [IRR] = 7; 95% CI <1-41) and for HPC (IRR = 13; 95% CI 4–48).ConclusionPPX-UV technology appears to be superior to manual cleaning alone for MRSA and HPC. Incorporating 15 minutes of PPX-UV exposure time to current hospital room cleaning practice can improve the overall cleanliness of patient rooms with respect to selected micro-organisms.

Effect of Variation in Test Methods on Performance of Ultraviolet-C Radiation Room Decontamination

“…4,9 The finding that interrupted and uninterrupted UV-C exposures were similarly effective suggests that the practice of running 2 cycles in different locations in the room will not adversely affect performance. [11][12] Finally, positioning of objects such as call buttons or tables in close proximity to UV-C devices has been recommended to take advantage of the fact that efficacy is reduced as distance from the device increases. [3][4][5][6][7][8] Our results suggest that orientation of objects such that the largest surface area is in parallel with the UV-C lamps may enhance efficacy.…”

“…[2][3][4][5][6][7][8][9][10] In hospital rooms, use of the devices has been shown to reduce the burden of pathogens on surfaces. [2][3][4][6][7][8][11][12][13] There have also been some reports of use of UV-C devices associated with reductions in healthcare-associated infections. [14][15][16] In addition to factors such as cost and ease of use, healthcare facilities considering the purchase of a UV-C room decontamination device must weigh claims regarding the effectiveness of different devices.…”

Evaluation of a Pulsed Xenon Ultraviolet Disinfection System for Reduction of Healthcare-Associated Pathogens in Hospital Rooms

“…8,11 In addition, our study provides 2 assessments not included in previous publications on PX-UV (ie, log reductions achieved by PX-UV on carriers and a comparison with continuous UV). Although the log reductions achieved by PX-UV on carriers at 10 minutes were relatively modest, this exposure time was sufficient to reduce contamination on real-world surfaces.…”

“…[1][2][3][4][5][6][7] Mercury gas bulbs primarily emit UV-C at 254 nm, whereas xenon gas bulbs produce a broad spectrum of radiation that encompasses the UV (100-280 nm) and visible (380-700 nm) spectra. [8][9][10][11][12] The UV-C radiation emitted by low pressure mercury bulbs is delivered in a continuous stream that gradually accumulates to lethal doses depending on duration of exposure and distance from the primary field of radiation. [1][2][3][4][5][6][7] The broad-range UV delivered by xenon bulbs is emitted in short, high-intensity pulses, possibly requiring a shorter duration of exposure to achieve lethal doses.…”

“…[1][2][3][4][5][6][7] The broad-range UV delivered by xenon bulbs is emitted in short, high-intensity pulses, possibly requiring a shorter duration of exposure to achieve lethal doses. [8][9][10][11][12] Given the increasing use of UV devices and variations in recommended cycle times, there is a need for evaluations of the real-world performance and comparative effectiveness of different devices. We previously demonstrated that a mobile, automated room disinfection device that utilizes mercury bulbs for emitting UV-C radiation is effective for reducing the frequency of positive methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), and Clostridium difficile culture results on high-touch surfaces in hospital rooms (Tru-D Rapid Room Disinfection device; Lumalier).…”