Use of atmospheric non-thermal plasma as a disinfectant for objects contaminated with methicillin-resistant Staphylococcus aureus

BackgroundHealth care-associated infections because of methicillin-resistant strains of Staphylococcus aureus (MRSA) are increasing worldwide despite current infection control measures. Novel methods for disinfection of MRSA would be useful.MethodsWe tested the effectiveness of atmospheric, non-thermal plasma discharge at killing S aureus, including USA300 strains, and at disinfecting experimentally contaminated hospital pagers.ResultsExposure of S aureus to plasma at different concentrations and for varying lengths of time resulted in up to a 4- to 5-log10 kill on tryptic soy agar plates within 10 minutes and was not toxic to epithelial cells. USA300 strains of MRSA were more resistant to plasma-based killing than other tested strains. Disinfection of hospital pagers experimentally coated with clinically relevant amounts of MRSA could be achieved in as little as 30 seconds.ConclusionGeneration of plasma is a promising method for disinfection of objects or surfaces that warrants further study in hospital settings. The USA300 strains of S aureus may be more resistant to disinfection than other strains.