A-251 Comparison of Antimicrobial Susceptibility Profiles of Enterobacteriaceae spp. Isolates from Retail Meat Products Imported from USA and Brazil or Domestically Produced on Caribbean Islands of St. Kitts and Grenada

Abstract

Abstract Background Enterobacteriaceae species, including Escherichia coli, Klebsiella and Salmonella, are endogenous colonizers of gastrointestinal tract of livestock animals, which pose potential health threats to humans, particularly for individuals with compromised immune systems (Guentzel 1996). The emergence of drug-resistant strains due to the overuse of antibiotics in agricultural practices have increased the urgency to evaluate zoonotic bacteria and to assess potential impact on human and animal health (Llor 2014). Project Aim and Methods The aim of this study is to compare the microbial prevalence and antimicrobial resistance profiles of Enterobacteriaceae isolates present on pork and poultry products domestically produced in the Caribbean Islands, St. Kitts and Grenada as compared to poultry imported from USA and Brazil. This study was conducted over a 4-year time period at University of Medicine and Health Sciences (UMHS) in St Kitts and at St. George’s University (SGU), Grenada. Microbial colonies were isolated on MacConkey agar after 24-hour incubation at 36°C in Buffered Peptone Water and identified using standard biochemical assays and API-20E test kit. Antimicrobial susceptibility was evaluated using the Kirby-Bauer disc diffusion on Mueller-Hinton plates. Results A total of 44 meat products from Caribbean Islands and 49 meat samples from Brazil and USA were processed to yield 64 and 60 bacterial isolates, respectively. Bacterial colonies isolated from imported meat products displayed higher incidence of antibiotic susceptibility to multiple classes of drugs (MDR = Multiple Drug Resistant) as compared to domestically produced meats. The prevalence of MDR bacteria was 45% MDR isolates from USA-imported chicken as compared to 13% MDR bacteria isolated from chicken domestically raised. Conclusions Imported meats exhibit a higher prevalence of antimicrobial resistance, particularly in the beta-lactam class of antibiotics, including amoxicillin and cephalosporins and fluroquinolones. The overuse of subtherapeutic antibiotics in mass scale livestock production is likely creating selective pressure for the overabundance of MDR strains in the gastrointestinal tract of animals. The findings of this study will be communicated to relevant community leaders and organizations in order to inform the development of strategies aimed at reducing the prevalence of antimicrobial resistance and identifying appropriate treatment options for associated infections.