title: Pork contaminated with Salmonella enterica serovar 4,[5],12:i:-, an emerging health risk for humans.
abstract: Salmonella enterica subsp. enterica serovar 4,[5],12:i:- is a monophasic variant of S. enterica serovar Typhimurium (antigenic formula 4,[5],12:i:1,2). Worldwide, especially in several European countries and the United States, it has been reported among the 10 most frequently isolated serovars in pigs and humans. In the study reported here, 148 strains of the monophasic serovar isolated from pigs, pork, and humans in 2006 and 2007 in Germany were characterized by various phenotypic and genotypic methods. This characterization was done in order to investigate their clonality, the prevalence of identical subtypes in pigs, pork, and humans, and the genetic relatedness to other S. enterica serovar Typhimurium subtypes in respect to the pathogenic and resistance gene repertoire. Two major clonal lineages of the monophasic serovar were detected which can be differentiated by their phage types and pulsed-field gel electrophoresis (PFGE) profiles. Seventy percent of the strains tested belonged to definite phage type DT193, and those strains were mainly assigned to PFGE cluster B. Nineteen percent of the strains were typed to phage type DT120 and of these 86% belonged to PFGE cluster A. Sixty-five percent of the isolates of both lineages carried core multiresistance to ampicillin, streptomycin, tetracycline, and sulfamethoxazole encoded by the genes bla(TEM1-like), strA-strB, tet(B), and sul2. No correlation to the source of isolation was observed in either lineage. Microarray analysis of 61 S. enterica serovar 4,[5],12:i:- and 20 S. enterica serovar Typhimurium isolates tested determining the presence or absence of 102 representative pathogenicity genes in Salmonella revealed no differences except minor variations in single strains within and between the serovars, e.g., by presence of the virulence plasmid in four strains. Overall the study indicates that in Germany S. enterica serovar 4,[5],12:i:- strains isolated from pig, pork, and human are highly related, showing their transmission along the food chain. Since the pathogenicity gene repertoire is highly similar to that of S. enterica serovar Typhimurium, it is essential that interventions are introduced at the farm level in order to limit human infection.
authors.affiliation: Federal Institute for Risk Assessment, National Reference Laboratory for Salmonella, Diedersdorfer Weg 1, Berlin, Germany.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Hauser
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: Kathrin
authors.initials: K
authors.lastname: Blank
authors.forename: Rita
authors.initials: R
authors.lastname: Prager
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Rabsch
authors.forename: Bernd
authors.initials: B
authors.lastname: Appel
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; D001426:Bacterial Proteins / Q000235:genetics; D001434:Bacteriophage Typing; D016000:Cluster Analysis; D016172:DNA Fingerprinting; D024901:Drug Resistance, Multiple, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D005516:Food Microbiology; D005838:Genotype; D005858:Germany / Q000453:epidemiology; D006801:Humans; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D012480:Salmonella Infections / Q000453:epidemiology* / Q000382:microbiology; D012481:Salmonella Infections, Animal / Q000453:epidemiology* / Q000382:microbiology; D012486:Salmonella typhimurium / Q000145:classification* / Q000302:isolation & purification*; D012703:Serotyping; D013552:Swine; D013553:Swine Diseases / Q000453:epidemiology* / Q000382:microbiology; D037521:Virulence Factors / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D037521:Virulence Factors
references.citation: J Clin Microbiol. 1999 Oct;37(10):3425
references.pmid: 10488227
references.citation: Appl Environ Microbiol. 2009 Feb;75(4):1011-20
references.pmid: 19114530
references.citation: J Clin Microbiol. 2001 Aug;39(8):2981-3
references.pmid: 11474028
references.citation: J Bacteriol. 2004 Sep;186(17):5883-98
references.pmid: 15317794
references.citation: Jpn J Infect Dis. 2003 Aug;56(4):151-5
references.pmid: 14583637
references.citation: J Clin Microbiol. 2002 Jun;40(6):2074-8
references.pmid: 12037067
references.citation: J Clin Microbiol. 2005 Jun;43(6):2736-40
references.pmid: 15956391
references.citation: J Bacteriol. 1981 Mar;145(3):1365-73
references.pmid: 7009583
references.citation: Foodborne Pathog Dis. 2009 May;6(4):407-15
references.pmid: 19292687
references.citation: Rev Inst Med Trop Sao Paulo. 2004 Mar-Apr;46(2):115-7
references.pmid: 15141285
references.citation: Euro Surveill. 2009 Apr 16;14(15):
references.pmid: 19371515
references.citation: J Clin Microbiol. 2009 Nov;47(11):3546-56
references.pmid: 19741087
references.citation: J Vet Med B Infect Dis Vet Public Health. 2004 Oct-Nov;51(8-9):389-92
references.pmid: 15525371
references.citation: Euro Surveill. 2007 Jun 01;12(6):E11-2
references.pmid: 17991400
references.citation: J Clin Microbiol. 2003 Jun;41(6):2395-400
references.pmid: 12791855
references.citation: Foodborne Pathog Dis. 2009 Jul-Aug;6(6):711-7
references.pmid: 19580448
references.citation: J Microbiol Methods. 2004 Nov;59(2):163-72
references.pmid: 15369852
references.citation: J Hyg (Lond). 1977 Apr;78(2):297-300
references.pmid: 321679
references.citation: J Clin Microbiol. 1998 Oct;36(10):2835-43
references.pmid: 9738029
references.citation: J Hyg (Lond). 1959 Sep;57:346-59
references.pmid: 13807011
references.citation: Avian Dis. 2007 Dec;51(4):958-64
references.pmid: 18251408
references.citation: Foodborne Pathog Dis. 2006 Spring;3(1):59-67
references.pmid: 16602980