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Published on: December 23, 2022
Vancomycin-resistant enterococci from animal sources in Korea.
Woo Kyung Jung1, Ji Youn Lim, Nam Hoon Kwon
1Department of Microbiology, College of Veterinary Medicine and BK21 Program for Veterinary Science, Seoul National University, Seoul, 151-742, Republic of Korea.
International Journal of Food Microbiology
|October 3, 2006
Summary
Vancomycin-resistant enterococci (VRE) were found in Korean animal products. The vanA gene, conferring vancomycin resistance, was most prevalent in poultry meat, with limited transferability observed.
Area of Science:
- Microbiology
- Food Science
- Veterinary Medicine
Background:
- Enterococci are common bacteria found in various environments, including food products.
- Vancomycin resistance in enterococci (VRE) is a significant public health concern.
- The prevalence and characteristics of VRE in food sources require ongoing investigation.
Purpose of the Study:
- To identify and characterize vancomycin-resistant enterococci (VRE) in meat, feces, and raw milk samples from Korea.
- To determine the prevalence of different vancomycin resistance genes (vanA, vanC1, vanC2) among isolated VRE.
- To assess the antimicrobial resistance patterns and transferability of vancomycin resistance in VRE.
Main Methods:
- Isolation and identification of enterococci from food and fecal samples.
- Minimum Inhibitory Concentration (MIC) testing for vancomycin resistance.
- Detection of vancomycin resistance genes (vanA, vanC1, vanC2) using molecular methods.
- Antimicrobial susceptibility testing for gentamicin and ampicillin.
- Genotyping of Enterococcus faecium isolates using pulsed-field gel electrophoresis (PFGE).
- Vancomycin resistance transferability assays.
Main Results:
- A total of 243 vancomycin-resistant enterococci (VRE) were isolated.
- The vanA gene was identified in 51 Enterococcus faecium isolates and one Enterococcus sp.
- vanC1 and vanC2 genes were found in Enterococcus gallinarum and Enterococcus casseliflavus, respectively.
- Of the vanA-carrying isolates, 4% showed high-level gentamicin resistance and 11% were resistant to ampicillin.
- PFGE revealed extensive genetic diversity among vanA-carrying E. faecium isolates.
- Vancomycin resistance was transferable in only two of the 52 vanA-carrying enterococci.
- VRE were recovered from various animal sources, with a high prevalence of vanA-carrying E. faecium in poultry meat.
Conclusions:
- Vancomycin-resistant enterococci, particularly Enterococcus faecium carrying the vanA gene, are present in the Korean food chain.
- Poultry meat represents a significant source for vanA-carrying E. faecium.
- While vancomycin resistance genes are present, their transferability appears limited in this study population.
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