Bactericidal activity of skin disinfectants on methicillin-resistant Staphylococcus aureus.
We studied bactericidal activity of 10% povidone-iodine, 0.5% chlorhexidine gluconate, and 0.5% chlorhexidine in 80% ethanol on four strains of methicillin-resistant and two strains of methicillin-susceptible Staphylococcus aureus. The pathogen was exposed to each of the disinfectants for 15, 30, 60, 120, and 240 s at room temperature. The inocula from these suspensions were cultured 72 h at 37 degrees C after the antimicrobial activity of the disinfectants in the suspensions was inactivated by 1:1000 dilution with neutralizer. No organism grew in any of the strains after exposure to 0.5% chlorhexidine in 80% ethanol. The 15-, 30-, and 60-s exposure to 10% povidone-iodine reduced the mean colony count by 55.2%, 91.2%, and 96.7%, respectively, and the exposures to 0.5% chlorhexidine gluconate reduced the mean colony count by 37.2%, 77.1%, and 93.3%, respectively. The difference in colony count between disinfectants was significant at 15- and 30-s exposures (P < 0.01 and 0.05, respectively). The results suggest that bactericidal activity of 0.5% chlorhexidine in 80% ethanol is more potent and more rapid against methicillin-susceptible and methicillin-resistant strains of S. aureus.
Sakuragi
T
T
Department of Anesthesiology, School of Medicine, Fukuoka University, Japan.
Yanagisawa
K
K
Dan
K
K
D002710:Chlorhexidine / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D004202:Disinfectants / Q000494:pharmacology*; D004347:Drug Interactions; D016106:Methicillin Resistance; D008826:Microbial Sensitivity Tests; D011206:Povidone-Iodine / Q000494:pharmacology*; D012867:Skin / Q000187:drug effects; D013211:Staphylococcus aureus / Q000187:drug effects*
D004202:Disinfectants; D011206:Povidone-Iodine; D002710:Chlorhexidine