Antimicrobial resistance of E. coli strains in ready-to-eat red meat products in Nakuru County, Kenya

Abstract

The demand for Ready-To-Eat (RTE) meat products is rising especially to the busy urban dwellers. Handling, processing, and selling methods of RTE contaminate them with pathogens. However, there is lack of evidence of the risk of antimicrobial resistance (AMR) of the pathogens. In this study, 105 RTE meat products were sampled across Nakuru County and assessed for Escherichia coli load, antimicrobial resistance (AMR), and presence of AMR genes. All the sampled meat products were contaminated with coliforms and E. coli but levels differed significantly (p < 0.05) with location of sample collection and type of RTE. Antimicrobial susceptibility test results of 30 E. coli isolates indicated high prevalence of the isolates’ resistance to co-trimoxazole, tetracycline, streptomycin, and ampicillin at 80%, 73%, 67%, and 67%, respectively. Antibiotic susceptibility of the isolates was highest towards ciprofloxacin and amikacin at 100% and 80%, respectively. All the 30 E. coli isolates showed 14 different AMR patterns, where each isolate was resistant to at least 2 antibiotics; a multiple antibiotic resistance (MAR) index of greater than 0.2. Meat samples collected from one sampling location, Salgaa had the highest number of multi-drug resistant E. coli isolates (88.9%). Molecular identification of AMR genes in four MAR isolates showed that tetA (for tetracycline resistance) and sul1 (for co-trimoxazole resistance) genes were present in all (100.0%) the isolates, while blaTEM (for ampicillin resistance) and strA (for streptomycin) genes were both present in two isolates. The four isolates were not E. coli O157 as confirmed by PCR for the O157 lipopolysaccharide O-antigen synthesis gene rfbE-O157. This study demonstrated the presence of MAR E. coli in RTE red meat products sold in Nakuru County, which is a human and animal public health concern, hence a need to urgently regulate and monitor the use of antimicrobials in animals.