title: Nationwide investigation of Shiga toxin-producing Escherichia coli among cattle in Japan revealed the risk factors and potentially virulent subgroups.
abstract: A nationwide study of Shiga toxin-producing Escherichia coli (STEC) was performed to determine the prevalence, characteristics and risk factors for fecal shedding of STEC among cattle in Japan. Information on rearing practices was also collected to identify risk factors for fecal shedding of STEC. STEC was isolated from 24·1% of samples (133/551) collected from 59·1% of farms (65/110). Bayesian clustering using the virulence marker profiles of the isolates subdivided the isolates into four genetically distinct groups, two of which corresponded to eae- or saa-positive STEC, which can cause severe disease in human. Both STEC groups exhibited characteristic phylogeny and virulence marker profiles. It is noteworthy that the tellurite resistance gene was not detected in all saa-positive STEC isolates, suggesting that the standard isolation method using tellurite might lead to an underestimation of the prevalence of saa-positive STEC. A multivariate logistic regression model using epidemiological information revealed a significantly (P < 0·01) high odds ratio on STEC fecal shedding in tie-stall housing and a low odds ratio in flat feed box and mechanical ventilation. Information on isolate characteristics of the two major pathotypes and risk factors in rearing practices will facilitate the development of preventative measures for STEC fecal shedding from cattle.
authors.affiliation: Division of Bacterial and Parasitic Disease Research,National Institute of Animal Health, National Agriculture and Food Research Organization,Tsukuba,Ibaraki,Japan.
authors.forename: K
authors.initials: K
authors.lastname: Lee
authors.affiliation: Division of Bacterial and Parasitic Disease Research,National Institute of Animal Health, National Agriculture and Food Research Organization,Tsukuba,Ibaraki,Japan.
authors.forename: M
authors.initials: M
authors.lastname: Kusumoto
authors.affiliation: Division of Bacterial and Parasitic Disease Research,National Institute of Animal Health, National Agriculture and Food Research Organization,Tsukuba,Ibaraki,Japan.
authors.forename: T
authors.initials: T
authors.lastname: Iwata
authors.affiliation: Department of Bacteriology I,National Institute of Infectious Diseases,Shinjuku,Tokyo,Japan.
authors.forename: S
authors.initials: S
authors.lastname: Iyoda
authors.affiliation: Division of Bacterial and Parasitic Disease Research,National Institute of Animal Health, National Agriculture and Food Research Organization,Tsukuba,Ibaraki,Japan.
authors.forename: M
authors.initials: M
authors.lastname: Akiba
mesh_terms: D000822:Animal Husbandry / Q000592:standards; D000818:Animals; D057138:Bacterial Shedding; D001499:Bayes Theorem; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000382:microbiology*; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D005243:Feces / Q000382:microbiology; D005260:Female; D007564:Japan / Q000453:epidemiology; D008297:Male; D010802:Phylogeny; D015995:Prevalence; D012307:Risk Factors; D054323:Shiga-Toxigenic Escherichia coli / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology*; D037521:Virulence Factors / Q000302:isolation & purification*
chemical_list: D037521:Virulence Factors
keywords: Cattle; Japan; Shiga toxin-producing E. coli
              ; prevalence; virulence factor