title: Virulence-associated genes, antimicrobial resistance and molecular typing of Salmonella Typhimurium strains isolated from swine from 2000 to 2012 in Brazil.
abstract: OBJECTIVE
  The aims of this study were to assess the pathogenic potential, antimicrobial resistance and genotypic diversity of Salmonella Typhimurium strains isolated in Brazil from swine (22) and the surrounding swine environment (5) from 2000 to 2012 and compare them to the profiles of 43 human strains isolated from 1983 to 2010, which had been previously studied.
  
  
  RESULTS
  The presence of 12 SPI-1, SPI-2 and plasmid genes was assessed by PCR, the antimicrobial susceptibility to 13 antimicrobials was determined by the disc diffusion assay and genotyping was performed using pulsed-field gel electrophoresis (PFGE), multiple-locus variable-number of tandem repeats analysis (MLVA) and ERIC-PCR. More than 77·8% of the swine strains carried 10 or more of the virulence markers. Ten (37%) strains isolated from swine were multi-drug resistant (MDR). All the molecular typing techniques grouped the strains in two main clusters. Some strains isolated from swine and humans were allocated together in the PFGE-B2, MLVA-A1, MLVA-B and ERIC-A1 clusters.
  
  
  CONCLUSIONS
  The genotyping results suggest that some strains isolated from swine and humans may descend from a common subtype and may indicate a possible risk of MDR S. Typhimurium with high frequency of virulence genes isolated from swine to contaminate humans in Brazil.
  
  
  CONCLUSIONS
  This study provided new information about the pathogenic potential, antimicrobial resistance and genotypic diversity of S. Typhimurium isolates from swine origin in Brazil, the fourth largest producer of pigs worldwide.
authors.affiliation: Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Universidade de São Paulo (USP), Ribeirão Preto, SP, Brazil.
authors.forename: F
authors.initials: F
authors.lastname: Almeida
authors.affiliation: Instituto Adolfo Lutz de Ribeirão Preto, Ribeirão Preto, SP, Brazil.
authors.forename: M I C
authors.initials: MI
authors.lastname: Medeiros
authors.affiliation: Embrapa Suínos e Aves, Concórdia, SC, Brazil.
authors.forename: J D
authors.initials: JD
authors.lastname: Kich
authors.affiliation: Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Universidade de São Paulo (USP), Ribeirão Preto, SP, Brazil.
authors.forename: J P
authors.initials: JP
authors.lastname: Falcão
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001938:Brazil; D024881:Drug Resistance, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D005838:Genotype; D006801:Humans; D008826:Microbial Sensitivity Tests; D058889:Molecular Typing; D010957:Plasmids / Q000235:genetics / Q000378:metabolism; D012481:Salmonella Infections, Animal / Q000382:microbiology*; D012486:Salmonella typhimurium / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D013552:Swine; D013553:Swine Diseases / Q000382:microbiology*; D037521:Virulence Factors / Q000235:genetics* / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D037521:Virulence Factors
keywords: Enterobacterial repetitive intergenic consensus PCR; MLVA; Salmonella Typhimurium; antimicrobial resistance; pulsed-field gel electrophoresis; virulence genes