Molecular Detection of Virulence Genes and Antibiotic Resistance Patterns of Escherichia coli O157:H7 Isolated from Raw Beef Sold in Abeokuta, South-West Nigeria

Escherichia coli O157:H7 is an important food-borne pathogen that can cause diarrhea, haemorrhagic colitis and haemolytic uremic syndrome. This study was conducted to investigate the prevalence, virulence genes and antibiotic resistance patterns of E. coli O157:H7 in raw beef meat sold in Abeokuta, South west Nigeria. One hundred and twenty samples of raw beef meat were collected from four abattoirs and examined for the presence of E. coli O157:H7. The virulence genes (stx1, stx2, eaeA and hlyA) were detected in E. coli O157:H7 isolates by polymerase chain reactions. The antibiotic resistance patterns of the isolates were determined using Kirby-Bauer disc diffusion method. Of 120 samples analyzed, 8 (6.67%) were contaminated with E. coli O157:H7, with highest prevalence rate (2.5%) found in beef samples collected from Rounder abattoir. The virulence genes (stx 1 and stx 2 genes) were detected in 7 (87.5%) of E. coli O157:H7 isolates while no eaeA and hlyA genes were found. All the E. coli O157:H7 isolates were highly resistant to tetracycline, ampicillin, erythromycin and chloramphenicol and sensitive to ciprofloxacin and streptomycin. The results of this study revealed that raw beef meat could be potential vehicles of transmitting multi-drug resistant, shiga toxin-producing E. coli O157:H7 to humans.Keywords: Pathogen, E. coli O157:H7, virulence genes, antibiotic-resistance, beef mea

Effect of Wrapping Materials on the Microbial Quality of some Street Vended Ready- to - Eat Rice

In many parts of Africa especially in Nigeria, ready-to-eat rice is commonly sold in several locations within the big cities and villages. In this study, one hundred samples of ready-to-eat rice were analyzed in some selected areas in Abeokuta, Ogun State, Nigeria. The effects of wrapping materials on the microbial quality of the rice samples were determined from seven different locations. The total bacterial counts ranged from 5.66 to 7.30 log10 cfu/g ,total coliform counts ranged from 5.07 to 7.33 log10 cfu/g and total fungal counts ranged from 5.19 to 6.03 log10 cfu/g. The b acterial species isolated from these samples were Bacillus subtilis, Klebsiella pneumonia and Staphylococcus aureus while the fungal species isolated include Aspergillus fumigatus, Mucor spp., and Penicillium sp. Factors such as improper storage as well as handling of the wrapping-materials of the food coupled with the attitude and practices of the vendors are likely to be responsible for the growth of these microorganisms. It was also discovered that improper cooking may contribute to microbial growth. Provision and enforcement of strict hygienic practices would go a long way in improving the quality of the ready-to-eat foods