Abstract:ObjectiveTo explore resistance of extendedspectrum βlactamase (ESBLs)and AmpCproducing Klebsiella pneumoniae (double positive K. pneumonia) to commonly used disinfectants, so as to provide reference for the control of bacterial transmission. MethodsFour different disinfectants: 75% ethanol, 2% glutaraldehyde, 500 mg/L available chlorine solution and compound iodine solution were used to test their efficacy on K. pneumoniae with suspension quantitative germicidal test and biofilm germicidal test, the killing rates of each disinfectant was calculated. ResultsIn suspension quantitative germicidal test, the killing rate of 4 kinds of disinfectants to the double positive strains was 5.0%-10.0%, 0.5%-3.5% lower than the double negative strains with a 1min and 3 min contact time respectively, the killing rates were all ≥99% with a 5min and 10 min contact time.The killing rate of 4 kinds of disinfectants to double positive strains in biofilm germicidal test was 10.0%-15.0%, 5.5%-19.0% and 0.1%-5.5% lower than that in suspension quantitative germicidal test with a 1 min, 5min and 10 min contact time respectively,the killing rates were all ≥99% with a 30 min contact time. ConclusionWhen contact time is short, the resistance of ESBLs and AmpCproducing K.pneumoniae to disinfectants are stronger than nonESBLs and nonAmpCproducing K.pneumoniae; when contact time is prolonged, commonly used disinfectants can kill ESBLs and AmpCproducing K. pneumoniae.