title: Shiga toxin-producing Escherichia coli O157 in beef and chicken burgers, and chicken carcasses in Buenos Aires, Argentina.
abstract: We describe the isolation and characterization of Shiga toxin (Stx)-producing Escherichia coli (STEC) O157:H7 from cooked and uncooked beef and chicken burgers and from chicken carcasses collected during sampling procedures in 2001 and 2002 in Buenos Aires City, Argentina. Of the 24 STEC O157:H7 strains isolated, 20 were recovered from 19 (6.8%) out of 279 samples of beef and chicken burgers, and 4 strains from 4 (10.3%) out of 39 chicken carcasses. The samples were analyzed following the USDA/FSIS 2002 method. The prevalent stx genotype was stx(2) and stx(2c) (12 strains, 50%). All strains were characterized as eae and ehxA-positive. By XbaI-PFGE, the strains yielded 10 different patterns. Eighteen out of 24 strains were grouped in four clusters: #1 (4 strains, AREXHX01.0043), #2 (4 strains, AREXHX01.0022), #3 (8 strains, AREXHX01.0139), and #4 (2 strains, AREXHX01.0200). Identical strains by phage typing, stx genotyping and PFGE were detected in uncooked and cooked beef and chicken burgers in different restaurants, which had been collected on the same or different sampling dates. These findings help to underline the importance of STEC O157 detection in meat products, to improve active surveillance, and to define control strategies in order to prevent new cases of STEC infection.
authors.affiliation: Servicio Fisiopatogenia, Departamento de Bacteriología, Instituto Nacional de Enfermedades Infecciosas, ANLIS Dr. Carlos G. Malbrán, Av. Vélez Sarsfield 563, (1281) Buenos Aires, Argentina. ichinen@anlis.gov.ar
authors.forename: Isabel
authors.initials: I
authors.lastname: Chinen
authors.forename: Sergio
authors.initials: S
authors.lastname: Epszteyn
authors.forename: Celia L
authors.initials: CL
authors.lastname: Melamed
authors.forename: Lorena
authors.initials: L
authors.lastname: Aguerre
authors.forename: Estela
authors.initials: E
authors.lastname: Martínez Espinosa
authors.forename: Mariana M
authors.initials: MM
authors.lastname: Motter
authors.forename: Ariela
authors.initials: A
authors.lastname: Baschkier
authors.forename: Eduardo
authors.initials: E
authors.lastname: Manfredi
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Miliwebsky
authors.forename: Marta
authors.initials: M
authors.lastname: Rivas
mesh_terms: D000818:Animals; D001118:Argentina; D002417:Cattle; D002645:Chickens / Q000382:microbiology*; D016000:Cluster Analysis; D003296:Cooking; D016521:Electrophoresis, Gel, Pulsed-Field; D019453:Escherichia coli O157 / Q000145:classification / Q000302:isolation & purification*; D005506:Food Contamination / Q000032:analysis*; D005511:Food Handling / Q000379:methods; D005838:Genotype; D006801:Humans; D008461:Meat Products / Q000382:microbiology*; D010802:Phylogeny; D011202:Poultry Products / Q000382:microbiology*