title: Diversity of Salmonella enterica serovar Derby isolated from pig, pork and humans in Germany.
abstract: Salmonella enterica serovar Derby (S. Derby) is one of the most prevalent serovars in pigs in Europe and in the U.S. and ranks among the 10 most frequently isolated serovars in humans. Therefore, a set of 82 epidemiologically unrelated S. Derby strains isolated between 2006 and 2008 from pigs, pork and humans in Germany was selected and investigated in respect to the transmission of clonal groups of the serovar along the food chain. Various phenotypic and genotypic methods were applied and the pathogenicity and resistance gene repertoire was determined. Phenotypically 72% of the strains were susceptible to all 17 antimicrobials tested while the others were monoresistant to tetracycline or multi-resistant with different resistance profiles. Four major clonal groups were identified based on PFGE, sequence data of the virulence genes sopA, sopB and sopD, VNTR-locus STTR5 and MLST revealing also the new sequence type ST774. Thirty different PFGE profiles were detected resulting in four clusters representing the four groups. The pathogenicity gene repertoire of 32 representative S. Derby strains analyzed by microarray showed six types with differences in the Salmonella pathogenicity islands, pathogenicity genes on smaller islets or prophages and fimbriae coding genes. The pathogenicity gene repertoire of the predominant types PAT DE1 and DE2 were most similar to the ones of S. Paratyphi B (dT+, O5-) and to a minor degree to S. Infantis and S. Virchow PATs. Overall this study showed that in Germany currently one major S. Derby clone is frequently isolated from pigs and humans. Contaminated pork was identified as one vehicle and consequently is a risk for human health. To prevent this serovar from entering the food chain, control measurements should be applied at the farm level.
authors.affiliation: National Reference Laboratory for Salmonella, Federal Institute for Risk Assessment, Diedersdorfer Weg 1, D-12277 Berlin, Germany.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Hauser
authors.forename: Franka
authors.initials: F
authors.lastname: Hebner
authors.forename: Erhard
authors.initials: E
authors.lastname: Tietze
authors.forename: Reiner
authors.initials: R
authors.lastname: Helmuth
authors.forename: Ernst
authors.initials: E
authors.lastname: Junker
authors.forename: Rita
authors.initials: R
authors.lastname: Prager
authors.forename: Andreas
authors.initials: A
authors.lastname: Schroeter
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Rabsch
authors.forename: Angelika
authors.initials: A
authors.lastname: Fruth
authors.forename: Burkhard
authors.initials: B
authors.lastname: Malorny
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D015373:Bacterial Typing Techniques; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field / Q000662:veterinary; D044404:Genomic Islands; D005838:Genotype; D005858:Germany; D006801:Humans; D008460:Meat / Q000382:microbiology*; D008826:Microbial Sensitivity Tests / Q000662:veterinary; D018598:Minisatellite Repeats; D058885:Multilocus Sequence Typing; D020411:Oligonucleotide Array Sequence Analysis; D012480:Salmonella Infections / Q000382:microbiology; D012481:Salmonella Infections, Animal / Q000382:microbiology; D019779:Salmonella enterica / Q000145:classification / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D013552:Swine / Q000382:microbiology*; D013553:Swine Diseases / Q000382:microbiology; D014774:Virulence; D037521:Virulence Factors / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D037521:Virulence Factors