Efficacy of pulsed-xenon ultraviolet light for disinfection of high-touch surfaces in an Ecuadorian hospital

Abstract

Background: Hospital environment in patient care has been linked on healthcare-associated infections (HAI). No touch disinfection technologies that utilize pulsed xenon ultraviolet light has been recognized to prevent infection in contaminated environments. The purpose of this study was: 1) to evaluate the effectiveness of pulsed-xenon ultraviolet light (PX-UV) disinfection for the reduction of bacteria on environmental surfaces of Hospital General Enrique Garcés, and 2) to evaluate the in-vitro efficacy against multi-drug resistance microorganisms.

Methods: This was a quality-improvement study looking at cleaning and disinfection of patient areas. During the study, a total of 146 surfaces from 17 rooms were sampled in a secondary 329-bed public medical center. Microbiological samples of high-touch surfaces were taken after terminal manual cleaning and after pulsed xenon ultraviolet disinfection. Cleaning staff were blinded to the study purpose and told clean following their usual protocols. For positive cultures PCR identification for carbapenemase-resistance genes (blaKPC, blaIMP, blaVIM, and blaNDM) were analyzed and confirmed by sequencing. The total number of colony forming units (CFU) were obtained and statistical analyses were conducted using Wilcoxon Rank Sum tests to evaluate the difference in CFU between terminal manual cleaning and after pulsed xenon ultraviolet disinfection.

Results: After manual disinfection of 124 surfaces showed a total of 3569 CFU which dropped to 889 CFU in 80 surfaces after pulsed xenon disinfection (p < 0.001). Overall, the surface and environmental contamination was reduced by 75% after PX-UV compared to manual cleaning and disinfection. There were statistically significant decreases in CFU counts of high touch surfaces in OR 87% (p < 0.001) and patient rooms 76% (p < 0.001). Four rooms presented serine carbapenemases blaKPC, and metallo beta-lactamases blaNDM, blaVIM, blaIMP. confirmed by PCR and sequencing. The in-vitro testing with endemic strains found that after five minutes of pulsed xenon ultraviolet exposure an 8-log reduction was achieved in all cases.

Conclusion: This study is one of the first of its kind in an Ecuador Hospital. We found that pulsed-xenon ultraviolet disinfection technology is an efficacious complement to the established manual cleaning protocols and guidelines in the significant reduction of MDRO.

Keywords: Carbapenemase; Disinfection; Environmental surfaces; HAIs; UV-C light.

Fig. 1

Average in CFU of High Touch Surfaces of patient rooms. On the horizontal axis are the surfaces sampled, and the vertical axis is expressed average of Colony counts units (CFU). °Other surfaces: external air duct, workbench, curtain, sink, door handle, soap dispenser, bath rail, bathroom sink, shower faucet, bathroom switch, bedside table, table

Fig. 2

Total CFU on High Touch Surfaces of OR. On the horizontal axis are the surfaces sampled, and the vertical axis is expressed number of Colony counts units (CFU)