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Updated: Jun 23, 2026
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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
Verocytotoxin-producing Escherichia coli (VTEC).
Mohamed A Karmali1, Victor Gannon, Jan M Sargeant
1Laboratory for Foodborne Zoonoses, Public Health Agency of Canada, Canada. Mohamed_Karmali@phac-aspc.gc.ca
Veterinary Microbiology
|May 5, 2009
Summary
Verocytotoxin-producing Escherichia coli (VTEC) cause global foodborne illnesses, including hemorrhagic colitis and hemolytic uremic syndrome. Controlling these zoonotic pathogens requires multifaceted strategies across the food chain, yet challenges persist.
Area of Science:
- Microbiology
- Food Safety
- Public Health
Background:
- Verocytotoxin-producing Escherichia coli (VTEC), including E. coli O157:H7, are significant zoonotic pathogens causing worldwide food and waterborne illnesses.
- VTEC infections can lead to severe conditions like hemorrhagic colitis and hemolytic uremic syndrome, characterized by thrombotic microangiopathy.
- Ruminants, particularly cattle, serve as natural reservoirs for VTEC, with 'supershedders' contributing significantly to environmental and food contamination.
Purpose of the Study:
- To review the pathogenesis of VTEC infections, focusing on the role of bacterial adhesins and effectors in host cell damage.
- To explore current and novel control strategies for VTEC along the 'farm to fork' continuum.
- To identify persistent scientific, technical, and regulatory challenges in preventing VTEC-associated human illnesses.
Main Methods:
- Literature review of VTEC pathogenesis, reservoirs, and transmission routes.
- Analysis of existing and emerging control measures in animal agriculture and food processing.
- Examination of challenges in VTEC prevention and control.
Main Results:
- VTEC infections damage host endothelial cells, leading to thrombotic microangiopathy.
- Control strategies include cattle vaccination, novel antimicrobials (bacteriocins, bacteriophage), and food processing interventions (pasteurization, irradiation).
- Despite interventions, significant challenges remain in effectively controlling VTEC.
Conclusions:
- Effective VTEC control necessitates a comprehensive approach addressing animal reservoirs, food production, and processing.
- Continued research and innovation are crucial to overcome existing hurdles in preventing VTEC-related human diseases.
- Interdisciplinary collaboration is essential for mitigating the global impact of VTEC infections.
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