Detection, Prevalence, and Pathogenicity of Non-O157 Shiga Toxin-ProducingEscherichia colifrom Cattle Hides and Carcasses

Abstract

Cattle are a major reservoir for Shiga toxin-producing Escherichia coli (STEC) and harbor these bacteria in the intestinal tract. The prevalence, concentration, and STEC serogroup isolated in cattle varies between individuals. Hide removal at slaughter serves as a major point of carcass contamination and ultimately beef products. Certain STEC serogroups, such as O26, O45, O103, O111, O121, O145, and O157, containing the intestinal adherence factor intimin, pose a large economic burden to food producers because of testing and recalls. Human infection with STEC can cause illnesses ranging from diarrhea to hemorrhagic colitis and hemolytic uremic syndrome, and is commonly acquired through ingestion of contaminated foods, often beef products. Previously, most studies focused on O157 STEC, but there is growing recognition of the importance of non-O157 STEC serogroups. This review summarizes detection methods, prevalence, and methods for prediction of pathogenicity of non-O157 STEC from cattle hides and carcasses. A synthesis of procedures is outlined for general non-O157 STEC and targeted detection of specific STEC serogroups. Standardization of sample collection and processing procedures would allow for more robust comparisons among studies. Presence of non-O157 STEC isolated from cattle hides and carcasses and specific factors, such as point of sample collection and season, are summarized. Also, factors that might influence STEC survival on these surfaces, such as the microbial population on hides and microbial adherence genes, are raised as topics for future investigation. Finally, this review gives an overview on studies that have used genetic and cell-based methods to identify specific phenotypes of non-O157 STEC strains isolated from cattle to assess their risk to human health.

Detection and isolation of Shiga toxin-producing Escherichia coli and microbial population counts on Argentinean Kosher beef for export to Israel

“…The stx detection rate on forequarters reported in this study was lower than described in the European Union (EU) and the US, and similar to other reports from Argentina. In the EU and the US, stx detection was in the range of 13.4-60.6 % on carcasses from abattoirs (Barkocy-Gallagher et al, 2003;Cobbold et al, 2008;Stromberg et al, 2018). In Argentina, previous studies have determined stx prevalence on carcasses from export abattoirs (Brusa et al, 2019(Brusa et al, , 2022Signorini et al, 2018).…”

“…In the present study, Top 7 STEC was not recovered from forequarters and primal cuts. The Top 7 STEC isolation rate on carcasses from the United States (US) (Barkocy-Gallagher et al, 2003;Cobbold et al 2008;Stromberg et al, 2018) and Canada (Bohaychuk et al, 2011) was 0.09-57.0 %. In Argentina, Masana et al (2010; reported 7.02 % of Top 7 STEC isolated from carcasses, and Brusa et al (2017) isolated Top 7 STEC from 0.02 % of primal cuts in Argentinean export abattoirs.…”

Isolation of Shiga toxin-producing strains of Escherichia coli from beef and swine carcasses and the characterization of their genes

“…(Ray & Bhunia, 2014;Bonardi et al, 2015;Bardasi et al, 2017). During processing, beef or swine carcasses can be contaminated with STEC directly by feces or from contaminated hides, which threatens food safety as carcasses are further processed into meat products (Stromberg et al, 2018). The contaminated raw meat and meat products are identified as major sources of STEC strains for humans.…”

“…Two types of Shiga toxin, stx1 and stx2 (encoded by stx1 and stx2 genes) are bacterial virulence STEC determinants that are associated with human disease and they are used as a markers for multiplex PCR (Puttalingamma et al, 2012;Rantsiou et al, 2012;Haugum et al, 2014;Hara-Kudo et al, 2016). STEC strains producing Stx2 are considered more virulent than Stx1 producers (Kavaliauskiene et al, 2017;Stromberg et al, 2018). Besides Shiga toxin production, another virulence factor of STEC is known.…”

Effects of Antimicrobial Interventions on Indicator Organisms during Beef Carcass Dressing

“…Food-producing animals often carry microorganisms such as pathogenic Escherichia coli (E. coli) and Salmonella asymptomatically (9,37). Unfortunately, carcasses can be contaminated with such pathogens by improper dressing procedures, making the final food product potentially contaminated if consumed or handled incorrectly (19,28).…”