Diverse genetic markers concordantly identify bovine origin Escherichia coli O157 genotypes underrepresented in human disease.
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ABSTRACT:
SUBMITTER: Whitworth J
PROVIDER: S-EPMC2798624 | biostudies-literature | 2010 Jan
REPOSITORIES: biostudies-literature
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Diverse genetic markers concordantly identify bovine origin Escherichia coli O157 genotypes underrepresented in human disease.
Whitworth Joshua J Zhang Yubei Y Bono James J Pleydell Eve E French Nigel N Besser Thomas T
Applied and environmental microbiology 20091030 1
Genetic markers previously reported to occur at significantly different frequencies in isolates of Escherichia coli O157:H7 obtained from cattle and from clinically affected humans concordantly delineate at least five genetic groups. Isolates in three of these groups consistently carry one or more markers rarely found among clinical isolates. ...[more]
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Project description:Shiga toxin-producing Escherichia coli (STEC)O157:H7 is a zoonotic pathogen of public health concern worldwide. To compare the local and large-scale geographic distributions of genotypes of STEC O157:H7 isolates obtained from various bovine and human sources during 2008–2011, we used pulsed-field gel electrophoresis and Shiga toxin–encoding bacteriophage insertion (SBI) typing. Using multivariate methods, we compared isolates from the North and South Islands of New Zealand with isolates from Australia and the United States. The STEC O157:H7 population structure differed substantially between the 2 islands and showed evidence of finer scale spatial structuring, which is consistent with highly localized transmission rather than disseminated foodborne outbreaks. The distribution of SBI types differed markedly among isolates from New Zealand, Australia, and the United States. Our findings also provide evidence for the historic introduction into New Zealand of a subset of globally circulating STEC O157:H7 strains that have continued to evolve and be transmitted locally between cattle and humans.
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