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Characterization of a Pathogenic Escherichia coli Strain Derived from Oreochromis spp. Farms Using Whole-Genome Sequencing
Published on: December 23, 2022
Shiga toxin-producing Escherichia coli: an overview
1Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada, N1G 2W1. cgyles@uoguelph.ca
Journal of Animal Science
|November 7, 2006
Summary
Cattle carry Shiga toxin-producing Escherichia coli (STEC), a pathogen causing severe human illness like bloody diarrhea and hemolytic uremic syndrome. Understanding STEC in cattle is crucial for preventing human infections.
Area of Science:
- Veterinary Medicine
- Microbiology
- Public Health
Background:
- Healthy cattle (dairy and beef) are significant reservoirs for diverse Shiga toxin-producing Escherichia coli (STEC) strains.
- STEC transmission to humans occurs via contaminated food/water or direct contact, leading to gastrointestinal illnesses and hemolytic uremic syndrome.
Purpose of the Study:
- To emphasize the role of cattle in human STEC infections.
- To detail STEC characteristics relevant to human disease pathogenesis.
Main Methods:
- Review of STEC epidemiology, diagnosis, and pathogenesis studies.
- Analysis of STEC virulence factors, including Shiga toxin (Stx) and the attaching and effacing (A/E) lesion.
- Examination of STEC serotyping, subtyping, and virulence typing systems.
Main Results:
- Serotype O157:H7 is frequently associated with severe human disease and outbreaks.
- The A/E lesion, induced by a type III secretion system, facilitates bacterial colonization.
- Shiga toxins (Stx1 and Stx2), encoded by bacteriophages, are critical for severe disease manifestations.
Conclusions:
- Preventing STEC-induced human disease requires understanding cattle carriage and shedding dynamics.
- Further research into factors influencing STEC virulence and host-pathogen interactions is essential for public health.
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