title: Predominance of vanA genotype among vancomycin-resistant Enterococcus isolates from poultry and swine in Costa Rica.
abstract: The use of avoparcin as a growth promoter is considered to have selected for vancomycin-resistant enterococci (VRE). In Costa Rica, the use of avoparcin for poultry and swine was intensive until the product was withdrawn from the market in 2000. We evaluated the presence of VRE in poultry, swine, and cattle fecal samples obtained during 1998 and 1999. A total of 185 VRE isolates were recovered from 116 out of 893 samples. Enterococcus faecium was the most frequently isolated species (50.8%), being predominant among poultry (71.6%) and swine (37.7%) isolates, but it was not recovered from the bovine samples. The second-most-frequently-isolated species from poultry and swine, respectively, were E. durans (23.2%) and E. faecalis (21.7%). E. casseliflavus was the only species obtained from bovine samples, but it was not found among the avian isolates. An evident predominance of the vanA determinant among vancomycin-resistant enterococcal species from poultry and swine, but not from cattle, was observed and was similar to the situation in European countries before avoparcin was forbidden. The diversity of the vanA determinant in the isolates was assessed by detection of the IS1251 insertion in the vanSH intergenic region and of the IS1476 insertion in the vanXY intergenic region. However, in none of the 154 vanA+ isolates recovered in this study were those insertions detected.
authors.affiliation: Centro de Investigación en Enfermedades Tropicales, Facultad de Microbiología, Universidad de Costa Rica, San José,Costa Rica.
authors.forename: Warner
authors.initials: W
authors.lastname: Bustamante
authors.forename: Angélica
authors.initials: A
authors.lastname: Alpízar
authors.forename: Silvia
authors.initials: S
authors.lastname: Hernández
authors.forename: Alexandra
authors.initials: A
authors.lastname: Pacheco
authors.forename: Natalia
authors.initials: N
authors.lastname: Vargas
authors.forename: Marco Luis
authors.initials: ML
authors.lastname: Herrera
authors.forename: Alvaro
authors.initials: A
authors.lastname: Vargas
authors.forename: Magaly
authors.initials: M
authors.lastname: Caballero
authors.forename: Fernando
authors.initials: F
authors.lastname: García
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics*; D019729:Carbon-Oxygen Ligases / Q000235:genetics*; D002417:Cattle; D002645:Chickens / Q000382:microbiology*; D003364:Costa Rica; D016983:Enterococcus / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D005243:Feces / Q000382:microbiology; D005838:Genotype; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology / Q000662:veterinary*; D008826:Microbial Sensitivity Tests; D016133:Polymerase Chain Reaction; D011201:Poultry Diseases / Q000382:microbiology; D013552:Swine / Q000382:microbiology*; D013553:Swine Diseases / Q000382:microbiology; D014640:Vancomycin / Q000494:pharmacology; D020713:Vancomycin Resistance
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; C071437:VanA ligase, Bacteria; D014640:Vancomycin; D019729:Carbon-Oxygen Ligases