title: Emergence of a Multidrug-Resistant Shiga Toxin-Producing Enterotoxigenic Escherichia coli Lineage in Diseased Swine in Japan.
abstract: EnterotoxigenicEscherichia coli(ETEC) and Shiga toxin-producingE. coli(STEC) are important causes of diarrhea and edema disease in swine. The majority of swine-pathogenicE. colistrains belong to a limited range of O serogroups, including O8, O138, O139, O141, O147, O149, and O157, which are the most frequently reported strains worldwide. However, the circumstances of ETEC and STEC infections in Japan remain unknown; there have been few reports on the prevalence or characterization of swine-pathogenicE. coli In the present study, we determined the O serogroups of 967E. coliisolates collected between 1991 and 2014 from diseased swine in Japan, and we found that O139, O149, O116, and OSB9 (O serogroup ofShigella boydiitype 9) were the predominant serogroups. We further analyzed these four O serogroups using pulsed-field gel electrophoresis (PFGE), multilocus sequence typing, and virulence factor profiling. Most of the O139 and O149 strains formed serogroup-specific PFGE clusters (clusters I and II, respectively), whereas the O116 and OSB9 strains were grouped together in the same cluster (cluster III). All of the cluster III strains belonged to a single sequence type (ST88) and carried genes encoding both enterotoxin and Shiga toxin. This PFGE cluster III/ST88 lineage exhibited a high level of multidrug resistance (to a median of 10 antimicrobials). Notably, these bacteria were resistant to fluoroquinolones. Thus, this lineage should be considered a significant risk to animal production due to the toxigenicity and antimicrobial resistance of these bacteria.
authors: Bacterial and Parasitic Disease Research Division, National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan kusu555@affrc.go.jp.
authors: Masahiro
authors: M
authors: Kusumoto
authors: Ehime Livestock Hygiene Service Center, Iyogun Masakicho, Ehime, Japan.
authors: Yuna
authors: Y
authors: Hikoda
authors: Ibaraki Kenhoku Livestock Hygiene Service Center, Mito, Ibaraki, Japan.
authors: Yuki
authors: Y
authors: Fujii
authors: Kumamoto Chuo Livestock Hygiene Service Center, Kumamoto, Japan.
authors: Misato
authors: M
authors: Murata
authors: Saga Chubu Livestock Hygiene Service Center, Saga, Japan.
authors: Hirotsugu
authors: H
authors: Miyoshi
authors: Department of Bacteriology, Faculty of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors: Yoshitoshi
authors: Y
authors: Ogura
authors: Division of Microbiology, Department of Infectious Diseases, Faculty of Medicine, University of Miyazaki, Kiyotake, Miyazaki, Japan.
authors: Yasuhiro
authors: Y
authors: Gotoh
authors: Bacterial and Parasitic Disease Research Division, National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan.
authors: Taketoshi
authors: T
authors: Iwata
authors: Department of Bacteriology, Faculty of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors: Tetsuya
authors: T
authors: Hayashi
authors: Bacterial and Parasitic Disease Research Division, National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Izumisano, Osaka, Japan.
authors: Masato
authors: M
authors: Akiba
mesh_terms: D000818:Animals; D016000:Cluster Analysis; D024901:Drug Resistance, Multiple, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D054307:Enterotoxigenic Escherichia coli / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D004927:Escherichia coli Infections / Q000382:microbiology / Q000662:veterinary*; D005838:Genotype; D007564:Japan; D058885:Multilocus Sequence Typing; D065288:Serogroup; D022621:Shiga Toxin / Q000096:biosynthesis*; D013552:Swine; D013553:Swine Diseases / Q000382:microbiology*; D037521:Virulence Factors / Q000032:analysis
chemical_list: D037521:Virulence Factors; D022621:Shiga Toxin