Prevalence of Shiga Toxin-Producing Escherichia coli (STEC) and Risk Characterization Based on Virulence Genes in Retail Raw Ground Meat of Beef, Veal, and Lamb in Canada

IF 2.1 4区农林科学 Q3 BIOTECHNOLOGY & APPLIED MICROBIOLOGY

Journal of food protection Pub Date : 2025-03-11 DOI:10.1016/j.jfp.2025.100483

Helen Zhang , Etsuko Yamamoto , Austin Markell , Catherine Carrillo , Annie Locas

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引用次数: 0

Abstract

Shiga toxin-producing Escherichia coli (STEC) are potentially pathogenic E. coli that may cause mild to severe gastrointestinal illnesses. STEC-contaminated foods of animal origin have been the most frequently implicated sources of foodborne outbreaks. A multiyear (2016 to 2021) targeted survey was conducted to investigate the prevalence of STEC in retail ground meats (beef, veal, and lamb). Samples were screened for the presence of Shiga toxin genes (stx) to identify presumptive samples, followed by culture and molecular confirmation of isolates to confirm the presence of stx genes and subsequent characterization by whole-genome-sequencing (WGS) for O serogroup and virulence genes (e.g., stx, eae, aggR). A total of 175 STEC strains were isolated from a total of 148 samples where the presence of viable STEC was confirmed out of 2,398 ground meat samples. This represented 1.2% (7/589 positive, 8 unique strains) of the beef samples, 4.7% (58/1,241 positive, 67 unique strains) of the veal samples, and 14.6% (83/568 positive, 100 unique strains) of the lamb samples. The intimin virulence gene, eae, was identified in the STEC strains of veal origin (9/67, 13.4%) only and were classified as belonging to risk level 1 (1/67), level 3 (2/67), and level 4 (6/67) according to the FAO/WHO risk categories. Risk level 2 STEC strains were of beef (2/8, 25.0%), veal (8/67, 11.9%), and lamb (1/100, 1.0%) origin. The majority of the STEC strains, 75.0% (6/8) of the beef, 67.2% (45/67) of the veal, and 94.0% (94/100) of the lamb STEC strains were classified as risk level 5 (lowest level) of the FAO/WHO risk categories. This study’s findings indicate that the current food safety control measures implemented for ground meats in Canada are effective at maintaining an acceptable level of possible contamination with STEC strains associated with severe clinical outcomes. Continued application of effective control measures and safe food handling practices by consumers will minimize the potential risk of foodborne infections from raw ground meats.

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来源期刊

Journal of food protection 工程技术-生物工程与应用微生物

CiteScore

4.20

自引率

5.00%

发文量

296

审稿时长

2.5 months

期刊介绍： The Journal of Food Protection® (JFP) is an international, monthly scientific journal in the English language published by the International Association for Food Protection (IAFP). JFP publishes research and review articles on all aspects of food protection and safety. Major emphases of JFP are placed on studies dealing with: Tracking, detecting (including traditional, molecular, and real-time), inactivating, and controlling food-related hazards, including microorganisms (including antibiotic resistance), microbial (mycotoxins, seafood toxins) and non-microbial toxins (heavy metals, pesticides, veterinary drug residues, migrants from food packaging, and processing contaminants), allergens and pests (insects, rodents) in human food, pet food and animal feed throughout the food chain; Microbiological food quality and traditional/novel methods to assay microbiological food quality; Prevention of food-related hazards and food spoilage through food preservatives and thermal/non-thermal processes, including process validation; Food fermentations and food-related probiotics; Safe food handling practices during pre-harvest, harvest, post-harvest, distribution and consumption, including food safety education for retailers, foodservice, and consumers; Risk assessments for food-related hazards; Economic impact of food-related hazards, foodborne illness, food loss, food spoilage, and adulterated foods; Food fraud, food authentication, food defense, and foodborne disease outbreak investigations.