title: Investigation of the genetic diversity among isolates of Salmonella enterica serovar Dublin from animals and humans from England, Wales and Ireland.
abstract: OBJECTIVE
  To assess the degree of genetic diversity among animal Salmonella Dublin UK isolates, and to compare it with the genetic diversity found among human isolates from the same time period.
  
  
  RESULTS
  One hundred isolates (50 human and 50 animal) were typed using plasmid profiling, XbaI-pulsed field gel electrophoresis (PFGE) and PstI-SphI ribotyping. Antimicrobial resistance data to 16 antibiotics was presented, and the presence of class-I integrons was investigated by real-time PCR. Seven different plasmid profiles, 19 ribotypes and 21 PFGE types were detected. A combination of the three methods allowed clear differentiation of 43 clones or strains. Eighteen isolates were resistant to at least one antimicrobial; five of them were multi-resistant and of these, only three presented class I integrons.
  
  
  CONCLUSIONS
  Ribotyping data suggest the existence of at least three very different clonal lines; the same distribution in well-defined groups was not evident from the PFGE data. The existence of a variety of clones in both animals and humans has been demonstrated. A few prevalent clones seem to be widely disseminated among different animal species and show a diverse geographical and temporal distribution. The same clones were found in animals and humans, which may infer that both farm and pet animals may act as potential vehicles of infection for humans. Some other clones seem to be less widely distributed. Clustering analysis of genomic fingerprints of Salmonella Dublin and Salm. Enteritidis isolates confirms the existence of a close phylogenetic relationship between both serotypes.
  
  
  CONCLUSIONS
  This paper describes the utility of a multiple genetic typing approach for Salm. Dublin. It gives useful information on clonal diversity among human and animal isolates.
authors.affiliation: Department of Bacterial Diseases, Veterinary Laboratories Agency-Weybridge, Addlestone, UK. E.liebana@VLA.DEFRA.gsi.gov.UK
authors.forename: E
authors.initials: E
authors.lastname: Liebana
authors.forename: L
authors.initials: L
authors.lastname: Garcia-Migura
authors.forename: C
authors.initials: C
authors.lastname: Clouting
authors.forename: C A
authors.initials: CA
authors.lastname: Cassar
authors.forename: F A
authors.initials: FA
authors.lastname: Clifton-Hadley
authors.forename: E A
authors.initials: EA
authors.lastname: Lindsay
authors.forename: E J
authors.initials: EJ
authors.lastname: Threlfall
authors.forename: S A
authors.initials: SA
authors.lastname: Chappell
authors.forename: R H
authors.initials: RH
authors.lastname: Davies
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis / Q000145:classification; D001717:Birds; D002417:Cattle; D002645:Chickens; D016000:Cluster Analysis; D004285:Dogs; D024881:Drug Resistance, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field / Q000379:methods; D014644:Genetic Variation; D006801:Humans; D032023:Integrons / Q000235:genetics; D010802:Phylogeny; D010957:Plasmids / Q000032:analysis / Q000302:isolation & purification; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D021521:Ribotyping / Q000379:methods; D019779:Salmonella enterica / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D012756:Sheep; D013552:Swine
chemical_list: D000900:Anti-Bacterial Agents