Bactericidal efficacy of five disinfectants against mycobacterium chelonei subsp.abscessus

  Objective   To compare the bactericidal efficacy of 5 disinfectants against a clinical isolate and standard strain of M.chelonei subsp.abscessus.

  Methods   Culture of clinical isolate of M.chelonei subsp.abscessus inoculated on mycobacter ia media slant for 7 days was transfer red to a sterile flask containing with glass beads, shake for 5 to 10 minutes, dilute to 10 ⁸ cfu/ml.0.1 ml of this suspension was added to 5 ml of disinfectant solution, after a certain contact time, 0.5 ml of this mixture was added to 4.5 ml neutralizer solution to inactivate the disinfectantcs effect, than 0.2 ml of the neutralized solution was inoculated on surface of L-Jmedia plate, cultured at 37℃ for 7 days to recover the viable bacteria.To evaluate the mycobactericidal efficacy of each disinfectant, killing rates of three disinfectant concentrations and four contact times were calculated.

  Results   ERIC solution with 40 mg/L available iodine, TC-191 solution with 40 mg/Lavailable chorine or 0.2% peracertic acid can kill the tested mycobacteria by more than 99.90% after 5-minute-contact time, GA-50 solution with 1% glutaraldehyde or 60% ethanol can also kill more than 99.90% of tested my cobacteria after 1-minute-contact time.

  Conclusion   These 5 disinfectants can kill the tested strain of M.chelonei subsp.abscessus to an acceptable level.