ARS | Publication request: EVALUATION OF RESISTANCE TO THE DISINFECTANT CHLORHEXIDINE GLUCONATE AMONG ENTEROTOXIGENIC SWINE ESCHERICHIA COLI

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: February 21, 2003
Publication Date: N/A

Technical Abstract: Background: The emergence of bacterial antimicrobial resistance has become a serious problem worldwide to both animal and human health. There is evidence that use of biocides (e.g. disinfectants) may contribute to the development of antibiotic resistance; however, information is limited among veterinary bacterial pathogens. The work shown here focuses on bacterial isolates obtained from a veterinary diagnostic laboratory and their evaluation against a disinfectant used for cleaning and disinfecting equipment, on animal husbandry premises, and on non-food producing animals. Methods: Eighty-nine enterotoxigenic Escherichia coli isolates originally obtained from neonatal pigs with diarrhea on five farms in Oklahoma were susceptibility tested using broth microdilution methods to chlorhexidine gluconate. Results: Of the 89 E. coli isolates tested, 43.8% showed low resistance in comparison to the laboratory control strain, JM-109. These isolates showed MICs of 2, 4, and 8 times that of the control, JM-109, with 5.6%, 25.8%, and 12.4% of the 89 isolates tested, respectively. Conclusion: The decreased susceptibility shown by these field isolates to the disinfectant chlorhexidine is interesting. Chlorhexidine is commonly used in clinical practice as a skin and mucous membrane antiseptic and as a disinfectant. Further surveillance is needed to detect bacteria that demonstrate decreased susceptibilities to this and other disinfectants used in animal production that are routinely used in clinical settings.