The Presence and Antibiotic Resistance of Non-O157 STEC on Lamb Carcasses

Abstract

There is an increasing trend in the prevalence of Hemolytic Uremic Syndrome (HUS) both in Türkiye and in the world. HUS might be caused by Shiga toxin (Stx)-producing Escherichia coli (STEC) O157 and strains of non-O157 STEC. The feces and fleece of lambs, and non-hygienic conditions present in the lamb slaughtering process are the main sources for STEC contaminations of lamb carcasses. In this study, the prevalence of STEC on lamb carcasses and, as an important global public health issue, the antibiotic resistance profiles of STEC strains isolated were aimed to be determined. The presence of stx was considered as STEC indicator. 16% of the carcasses (8/50) were found to be contaminated by E. coli. The analysis showed that none of the strains isolated were O157 serotype. But, 5 out of 8 strains isolated carried stx1 and stx2 genes so they were identified as non-O157 cytotoxigenic E. coli. Antibiotic resistance profiles of the isolates were determined by using Kirby Bauer method. All of the isolates were found to be resistant at least one antibiotics investigated, and as the most resistance rate found 87.5% of the isolates were resistant to both gentamycin and pefloxacine. In addition, 75% of the isolates were multidrug resistant (MDR), and overall MAR (Multi Antimicrobial Resistant) index of isolates was 0.4. As a result, STEC contamination on lamb carcasses was considered to be a risk for both children and adults for HUS, and high antibiotic resistance of the isolates observed also increased the public health hesitations. Reassessment of the slaughtering process based on the HACCP (Hazard Analysis and Critical Control Points) requirements and taking necessary actions/measures to control cross contaminations are thought to be crucial steps to reduce pathogenic bacteria incidence in food chain.