Microbial Flora and Food Borne Pathogens on Minced Meat and their Susceptibility to Antimicrobial Agents

Abstract

BACKGROUND: Food-borne pathogens are the leading cause of illness and death in developing countries. Changes in eating habits, mass catering, unsafe food storage conditions and poor hygiene practices are major contributing factors to food associated illnesses. In Ethiopia, the widespread habit of raw beef consumption is potential cause for food borne illnesses. The present study aimed at investigating the microbial quality of meat available in common retail shops, restaurants and abattoir of Jimma City and determining susceptibility pattern of bacterial isolates. METHOD: A total of 165 samples from food establishments, butcher shops and a slaughter houses were processed and analyzed for the presence of indicator bacterial and potential food pathogens using standards methods. Antimicrobial susceptibility test was performed for Salmonella, Shigella and Staphylococcus aureus isolates using Kirby-Bauer disk diffusion method. RESULTS: A total of 165 samples were collected from twenty four hotels and five butchers and an abattoir. Various food borne pathogens were isolated in 13 (43.3%) and indicator organisms in 29 (96.7%) out of the thirty food establishments (hotels, butchery and abattoir). Overall, ten different bacterial species were isolated which included, proteus spp 89 (53.9%), E. coli 44 (26.6%), Providencia spp 23 (13.9%) Citrobacter spp 15(9%), Pseudomonas spp 9 (5.5%), Klebsiella spp 2 (1.2%), Enterobacter spp 2 (1.2%), Salmonella spp 2(1.2%), and Shigella species 1 (0.6%). Out of the 44 E. coli isolates 37 (84%) were thermo tolerant E. coli and out of the gram positive organisms identified 20 (12.1%) were Staphylococcus aureus isolates. From the two Salmonella isolates one was susceptible against all 12 tested antimicrobials, while the other to all the 11 except cephalexin. Shigella dysentery was resistant only to co-trimoxazole and tetracycline. Out of the 20 S. aureus isolates, 90% showed resistance to oxacillin, 85% to ampicillin, 65% to erythromycin, 60% to amoxicillin, 35% to streptomycin, and 20% to vancomycin and all isolates were sensitive to co-trimoxazole (100%). In this study, 90% (18/20) of the S. aureus isolates were Methicillin Resistant Staphylococcus aureus. CONCLUSION: In this study high percentage of indicator organisms as well as food borne pathogens were identified, which shows unhygienic condition of handling and processing in the food establishments. Our data also confirmed the presence of resistant food pathogens; particularly Staphylococcus aureus isolates which are Methicillin Resistant Staphylococcus aureus and multidrug resistant that emphasizes close follow up in the utilization of antibiotics. Therefore, meat handlers and sellers should be educated on the adverse effect of lack of proper personal, environmental hygiene and sanitation. In addition, consumers should be made aware of the risk of consuming raw and inadequately cooked meat.