[Effects of antiseptics against methicillin-resistant Staphylococcus aureus]

Various antiseptics, commonly used in hospital, were tested against methicillin-resistant Staphylococcus aureus (MRSA) at high concentrations (approximately 10(9) CFU/ml) and in short time exposures. The antiseptic solutions of 0.05% alkyldiaminoethylglycine hydrochloride, 0.05% benzalkonium chloride, 0.2% povidone-iodine gargle and 0.03% dominophen bromide produced 1,000 to 1/100,000 reduction after a 30 sec exposure. 7.5 % povidone-iodine scrub and 0.2% benzalkonium chloride in 83% ethanol were most effective, reducing MRSA under detection limits. (less than 10 CFU/ml) 0.05% chlorhexidine gluconate was less effective, producing no evident reduction even after 1 min of exposure. Though 0.2% povidone solution reduced MRSA under detection limits at 37, 24 hrs incubation, colonies of several strains were detected after 48 hrs extended incubation. This suggests the existence of strains resistant to the antiseptic solution of povidone-iodine. We recommend that the disinfection for these strains should be repeated short time disinfection, because repeated short time exposure (15 sec 2 times) of antiseptics was more effective than one long time exposure (30 sec once).