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Updated: Jun 20, 2026
05:02
A 1.5 Hour Procedure for Identification of Enterococcus Species Directly from Blood Cultures
Published on: February 10, 2011
vanA in Enterococcus faecium, Enterococcus faecalis, and Enterococcus casseliflavus detected in French cattle
Marisa Haenni1, Estelle Saras, Pierre Châtre
1Agence Française de Sécurité Sanitaire des Aliments (AFSSA), Unité Bactériologie Bovine et Hygiène des Viandes, Lyon, France.
Foodborne Pathogens and Disease
|August 22, 2009
Summary
Vancomycin resistance in enterococci was found in French cattle, specifically in E. faecalis, E. faecium, and E. casseliflavus strains carrying the vanA gene. This highlights the potential re-emergence of glycopeptide resistance in food-producing animals.
Area of Science:
- Veterinary Microbiology
- Antimicrobial Resistance
- Food Safety
Background:
- Glycopeptide resistance in enterococci is a significant public health concern.
- The ban on avoparcin, a glycopeptide antibiotic, aimed to reduce resistance in food-producing animals.
- Monitoring resistance in livestock remains crucial despite regulatory measures.
Purpose of the Study:
- To investigate the prevalence of van-mediated glycopeptide resistance in enterococci from French cattle.
- To characterize the genetic elements responsible for resistance.
- To assess the potential for transfer and co-selection of resistance genes.
Main Methods:
- Fecal sample collection from healthy and sick cattle.
- Screening of enterococci for vancomycin resistance.
- Molecular characterization of resistance genes (vanA, vanB, vanC).
- Phenotypic and genotypic analysis of resistance mechanisms.
Main Results:
- Vancomycin resistance was detected in Enterococcus gallinarum, Enterococcus casseliflavus, Enterococcus faecalis, and Enterococcus faecium.
- The prototypic VanA element was identified in all resistant strains.
- One E. casseliflavus strain exhibited a VanB phenotype with a vanA-vanC genotype.
- Acquired vanA genes were detected more than a decade after the avoparcin ban.
Conclusions:
- Acquired vanA genes persist in French cattle populations.
- Antibiotic use in calves may facilitate the re-emergence of glycopeptide resistance via co-selection.
- The findings raise concerns for human health due to potential transmission pathways.
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