title: Outbreak with clonally related isolates of Corynebacterium ulcerans in a group of water rats.
abstract: BACKGROUND
  The zoonotic bacterium Corynebacterium ulcerans may be pathogenic both in humans and animals: toxigenic strains can cause diphtheria or diphtheria-like disease in humans via diphtheria toxin, while strains producing the dermonecrotic exotoxin phospholipase D may lead to caseous lymphadenitis primarily in wild animals. Diphtheria toxin-positive Corynebacterium ulcerans strains have been isolated mainly from cattle, dogs and cats.
  
  
  RESULTS
  Here, we report a series of ten isolations of Corynebacterium ulcerans from a group of water rats (Hydromys chrysogaster) with ulcerative skin lesions, which were kept in a zoo. The isolates were clearly assigned to species level by biochemical identification systems, Fourier-transform infrared-spectroscopy, Matrix-assisted laser desorption/ionization-time of flight mass spectrometry and partial rpoB sequencing, respectively. All ten isolates turned out to represent the same sequence type, strongly indicating a cluster of infections by clonally-related isolates as could be demonstrated for the first time for this species using multilocus sequence typing. Unequivocal demonstration of high relatedness of the isolates could also be demonstrated by Fourier-transform infrared-spectroscopy. All isolates were lacking the diphtheria toxin encoding tox-gene, but were phospholipase D-positive.
  
  
  CONCLUSIONS
  Our results indicate that water rats represent a suitable new host species that is prone to infection and must be regarded as a reservoir for potentially zoonotic Corynebacterium ulcerans. Furthermore, the applied methods demonstrated persistent infection as well as a very close relationship between all ten isolates.
authors.affiliation: Landesbetrieb Hessisches Landeslabor, Schubertstr. 60, 35392, Gießen, Germany. tobias.eisenberg@lhl.hessen.de.
authors.forename: Tobias
authors.initials: T
authors.lastname: Eisenberg
authors.affiliation: Chemisches und Veterinäruntersuchungsamt Stuttgart, Schaflandstr. 3/2, 70736, Fellbach, Germany. norman.mauder@cvuas.bwl.de.
authors.forename: Norman
authors.initials: N
authors.lastname: Mauder
authors.affiliation: Chemisches und Veterinäruntersuchungsamt Stuttgart, Schaflandstr. 3/2, 70736, Fellbach, Germany. matthias.contzen@cvuas.bwl.de.
authors.forename: Matthias
authors.initials: M
authors.lastname: Contzen
authors.affiliation: Chemisches und Veterinäruntersuchungsamt Stuttgart, Schaflandstr. 3/2, 70736, Fellbach, Germany. joerg.rau@cvuas.bwl.de.
authors.forename: Jörg
authors.initials: J
authors.lastname: Rau
authors.affiliation: Institute of Hygiene and Infectious Diseases of Animals, Justus Liebig University Giessen, Frankfurter Strasse 85-89, 35392, Giessen, Germany. christa.ewers@vetmed.uni-giessen.de.
authors.forename: Christa
authors.initials: C
authors.lastname: Ewers
authors.affiliation: Landesbetrieb Hessisches Landeslabor, Schubertstr. 60, 35392, Gießen, Germany. karen.schlez@lhl.hessen.de.
authors.forename: Karen
authors.initials: K
authors.lastname: Schlez
authors.affiliation: Landesbetrieb Hessisches Landeslabor, Schubertstr. 60, 35392, Gießen, Germany. gisa.althoff@lhl.hessen.de.
authors.forename: Gisa
authors.initials: G
authors.lastname: Althoff
authors.affiliation: Zoo Frankfurt, Bernhard-Grzimek-Allee 1, 60316, Frankfurt, Germany. nicole.schauerte@stadt-frankfurt.de.
authors.forename: Nicole
authors.initials: N
authors.lastname: Schauerte
authors.affiliation: Zoo Frankfurt, Bernhard-Grzimek-Allee 1, 60316, Frankfurt, Germany. christina.geiger@stadt-frankfurt.de.
authors.forename: Christina
authors.initials: C
authors.lastname: Geiger
authors.affiliation: National Consiliary Laboratory on Diphtheria, Bayerisches Landesamt für Gesundheit und Lebensmittelsicherheit, Veterinärstraße 2, 85764, Oberschleißheim, Germany. gabriele.margos@lgl.bayern.de.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Margos
authors.affiliation: National Consiliary Laboratory on Diphtheria, Bayerisches Landesamt für Gesundheit und Lebensmittelsicherheit, Veterinärstraße 2, 85764, Oberschleißheim, Germany. regina.konrad@lgl.bayern.de.
authors.forename: Regina
authors.initials: R
authors.lastname: Konrad
authors.affiliation: National Consiliary Laboratory on Diphtheria, Bayerisches Landesamt für Gesundheit und Lebensmittelsicherheit, Veterinärstraße 2, 85764, Oberschleißheim, Germany. andreas.sing@lgl.bayern.de.
authors.forename: Andreas
authors.initials: A
authors.lastname: Sing
mesh_terms: D000818:Animals; D000836:Animals, Zoo; D015373:Bacterial Typing Techniques; D016000:Cluster Analysis; D003352:Corynebacterium / Q000737:chemistry / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D003354:Corynebacterium Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D012321:DNA-Directed RNA Polymerases / Q000235:genetics; D004167:Diphtheria Toxin / Q000235:genetics; D004196:Disease Outbreaks; D005838:Genotype; D008297:Male; D008969:Molecular Sequence Data; D058885:Multilocus Sequence Typing; D051189:Murinae; D010739:Phospholipase D / Q000235:genetics; D012376:Rodent Diseases / Q000453:epidemiology* / Q000382:microbiology*; D017422:Sequence Analysis, DNA; D017192:Skin Diseases, Bacterial / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D013057:Spectrum Analysis; D037521:Virulence Factors / Q000235:genetics
chemical_list: D004167:Diphtheria Toxin; D037521:Virulence Factors; D012321:DNA-Directed RNA Polymerases; C105078:RNA polymerase beta subunit; D010739:Phospholipase D