Disinfection efficacy of high-intensity ultraviolet disinfection robot on multidrug-resistant organisms

Abstract:

Objective To evaluate the disinfection efficacy of an autonomous mobile direct-radiation high-intensity ultraviolet disinfection robot on multidrug-resistant organisms (MDROs) on environmental object surface. Methods Slides smeared with 0.5×10⁶ CFU/mL carbapenem-resistant Klebsiella pneumoniae (CRKP) and methicillin-resistant Staphylococcus aureus (MRSA) were prepared and disinfected by irradiation of disinfection robot at diffe-rent duration, distances, angles, shielding and moving status. After disinfection, bacterial slides were scraped with sterile cotton swabs and smeared on blood agar plates, plates were then cultured at 35℃ for 48 hours. Bacteria count as well as killing rate and killing logarithm value under different conditions were calculated. Results Under static status, the killing rates of both CRKP and MRSA at an irradiation distance of 1 m for 5 minutes and 10 minutes were 100%, and all killing logarithms were ≥ 3. With irradiation at a distance of 1 m for 5 minutes and 10 minutes respectively, the killing rates of both CRKP and MRSA with and without plastic wrap were 100%, and all killing logarithms were ≥ 3, disinfection efficacy reached the standard. In moving state, the killing rates of CRKP and MRSA at all detected angles were 100%, all killing logarithm value were ≥ 3, and the disinfection efficacy reached standard. Conclusion High-intensity ultraviolet disinfection robot can achieve good disinfection efficacy on MDROs in a short time, the disinfection efficacy remains in case of materials with high penetration rate.