Evaluation of Process Control to Prevent Contamination of Beef with Non-O157 Shiga Toxin-producing Escherichia coli (STEC) in U.S. Export Abattoirs in Honduras and Nicaragua

The objectives of this project were to determine (1) the prevalence of non-O157 STEC on beef hides and carcasses in export abattoirs in Honduras (Plant A) and Nicaragua (Plant B) and (2) whether current practices and interventions controlled final carcass contamination. Samples were collected on the foreshanks from the hides, at pre-evisceration and after application of an antimicrobial treatment. In Plant A, 23.3% (7/30) of hides contained at least one STEC serogroup, whereas in Plant B, 90.0% (45/50) tested positive. Pre-evisceration samples had a prevalence of 6.7% (2/30) for Plant A and of 0% for Plant B. No STEC were detected after antimicrobial intervention. Serogroups O26, O45, and O121 were the most prevalent in plant A, with frequencies of 27/75 (36.0%), 24/75 (32.0%), and 18/75 (24.0%), respectively. In Plant B, O26 and O121 were predominant, with 47.5% (38/80) and 46.3% (37/80), respectively. STEC were present on the hides, but current hygienic practices and interventions effectively controlled them and reduced final carcass contamination.