title: Virulence characteristics of Yersinia pseudotuberculosis isolated from breeding monkeys in Japan.
abstract: Between April 2001 and 2007, 18 Yersinia pseudotuberculosis outbreaks occurred in breeding monkeys at 12 zoological gardens in Japan, and 28 monkeys of 8 species died. A total of 18 Y. pseudotuberculosis strains from the dead monkeys, comprising one strain per outbreak, were examined for serotype and the presence of the virulence genes virF, inv, ypm (ypmA, ypmB and ypmC) and irp2. Of the 18 Y. pseudotuberculosis strains, 7 (38.9%) were serotype 4b, 7 (38.9%) were serotype 1b, and there was one each of serotypes 2b, 3, 6 and 7. All the 18 strains examined harbored virF and inv. Sixteen (88.9%) strains, including the strain of serotype 7, harbored ypmA. However, no strain harbored ypmB, ypmC and irp2. This study demonstrated that among other pathogenic factors, almost all the Y. pseudotuberculosis isolated from the outbreaks had the ypm gene encoding the superantigenic toxin, YPM. As most of the monkeys who died in those outbreaks originated from South America and other regions, where the presence of the ypm gene have not been reported, YPM might be the cause, or at least the most important factor for, the high mortality of the breeding monkeys infected by Y. pseudotuberculosis in Japan. This is also the first report of a fatal case due to Y. pseudotuberculosis serotype 7 infection in the world.
authors.affiliation: Division of Animal Science, Institute of Symbiotic Science and Technology, Tokyo University of Agriculture and Technology, Fuchu, Tokyo, Japan.
authors.forename: Taketoshi
authors.initials: T
authors.lastname: Iwata
authors.forename: Yumi
authors.initials: Y
authors.lastname: Une
authors.forename: Alexandre Tomomitsu
authors.initials: AT
authors.lastname: Okatani
authors.forename: Yukio
authors.initials: Y
authors.lastname: Kato
authors.forename: Aya
authors.initials: A
authors.lastname: Nakadai
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Lee
authors.forename: Maiko
authors.initials: M
authors.lastname: Watanabe
authors.forename: Takahide
authors.initials: T
authors.lastname: Taniguchi
authors.forename: AbdelAzim Elsayed
authors.initials: AE
authors.lastname: Elhelaly
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Hirota
authors.forename: Hideki
authors.initials: H
authors.lastname: Hayashidani
mesh_terms: D000818:Animals; D000836:Animals, Zoo; D001426:Bacterial Proteins / Q000235:genetics*; D004196:Disease Outbreaks / Q000662:veterinary*; D005260:Female; D000882:Haplorhini; D007564:Japan / Q000453:epidemiology; D008297:Male; D008992:Monkey Diseases / Q000453:epidemiology / Q000382:microbiology*; D012703:Serotyping; D013045:Species Specificity; D014774:Virulence / Q000235:genetics; D037521:Virulence Factors / Q000235:genetics; D015011:Yersinia pseudotuberculosis / Q000145:classification / Q000235:genetics / Q000472:pathogenicity*; D015012:Yersinia pseudotuberculosis Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*
chemical_list: D001426:Bacterial Proteins; D037521:Virulence Factors; C093313:Yersinia pseudotuberculosis-derived mitogen