ABSTRACT
OBJECTIVE To study the disinfectant resistance of multi-drug resistant Escherichia coli strains isolated clinically,and to find out the efficacy of disinfectants commonly used in killing multi-drug resistant E.coli strains.METHODS Minimal inhibitory concentration(MIC) and suspension quantitative germicidal test were used.Compared with standard strains,strains of multi-drug resistant E.coli isolated clinically were determined the resistance to four kinds of disinfectants including benzalkonium bromide etc.RESULTS A higher MIC of benzalkonium bromide compared with standard strains was observed in 61.9% of all 21 multi-drug resistant E.coli strains,and as for povidone iodine and NaClO,the ratio was 71.4% and 14.3%,respectively.All multi-drug resistant E.coli strains had the same MICs of peroxyacetic acid with standard strains.The above-mentioned 4 disinfectants commonly used at the routine concentrations killed 100% of the resistant strains of E.coli within 5 minutes.CONCLUSIONS The resistance to benzalkonium bromide and povidone iodine of multi-drug resistant E.coli isolated clinically is higher than standard strains;and 4 kinds of disinfectants commonly used are effective for multi-drug resistant E.coli strains isolated clinically.