Abstract
The effects of hot water and ozonized solution used for disinfection were evaluated in antiseptic-resistant strains of methicillin-resistant Staphylococcus aureus (MRSA). The viable counts of the antiseptic-sensitive and -low level-resistant strains were decreased to ≤102 cfu/ml by exposure to 60°C water within 2 minutes. However, the viable counts of the high levelresistant strain were not decreased to ≤102 cfu/ml by more than 5 minutes exposure to 65°C water.
The viable counts of the antiseptic-sensitive, -low level-resistant, and -high level-resistant strains were decreased to ≤102 cfu/ml by exposure to 70°C water within 30 seconds, 30 seconds, and 2 minutes, respectively. Sensitivity to hot water of antiseptic-sensitive derivatives, eliminated the antiseptic-resistant gene ebr, was higher than that of the original antiseptic-resistant strain. Sensitivity to ozonized solution of antiseptic-resistant strain was also lower than that of the antiseptic-sensitive strain. The viable counts of the antiseptic-high level-resistant strain were decreased to ≤102 cfu/ml by exposure to 1.5 ppm ozonized solution within 30 seconds.
These results clearly confirm that the antiseptic-resistant gene ebr was relative to a decline in the sensitivity to hot water and ozonized solution in antiseptic-resistant strains, and that 70°C water and 1.5 ppm ozonized solution are a useful means of disinfecting instruments and devices contaminated with antiseptic-resistant strains of MRSA.
