The effect of pulsed-xenon ultraviolet disinfection on surfaces contaminated with vancomycin-resistant Enterococci in a Japanese hospital.

INTRODUCTION

Recently, a worldwide outbreak of vancomycin-resistant Enterococci (VRE) was reported. However, due to the low incidence of VRE infection and colonization, VRE contamination of hospital environments has not been fully investigated in Japan.

METHODS

Surfaces were swabbed, before and after manual cleaning and after pulsed xenon ultraviolet (PX-UV) disinfection, in five patient rooms that had been occupied by patients colonized with VRE. Difference in the number of VRE-positive samples and VRE colony forming units (CFUs), before and after disinfection, for each cleaning method was estimated.

RESULTS

We detected VRE contamination in 22/60 (37%) and 14/60 (23%) samples collected before and after manual cleaning, respectively. In contrast, VRE contamination was not detected in the samples collected after PX-UV disinfection. In addition, 3/5 (60%) spray nozzles of electric warm-water bidet toilet seats were found to be contaminated with VRE before terminal cleaning. Manual cleaning caused a significant decrease in the number of VRE CFUs compared with that before cleaning (P = 0.031). PX-UV disinfection also caused a significant decrease in the number of VRE CFUs compared to that of manual cleaning (P < 0.001).

CONCLUSION

We identified hot spots of severe contamination, such as private bathrooms in patient rooms and areas around the bed of patients using diapers and required assistance. VRE contamination persisted even after terminal disinfection; PX-UV disinfection in addition to terminal disinfection was effective at eliminating VRE contamination. These results can be useful in controlling the spread of VRE infections in Japanese hospitals.