Q-234. Plasmid Profile and Antibiotic Susceptibility Pattern of E. coli 0157:H7 Isolated from Human and Environmental Sources in Lagos Area of Nigeria

O. O. Aboaba1, S. I. Smith2, H. T. Goodluck2, P. G. Odeigha1;
1Univ. of Lagos, Lagos, NIGERIA, 2Nigerian Inst. of Med. Res., Lagos, NIGERIA.

BACKGROUND: Previous work indicated the prevalence of E. coli 0157:H7 in apparently healthy farm animals in Southern Nigeria. The most common routes of infection caused by this organism are person to person, animal to man as well as through water. The unavailability of portable water and indiscriminate disposal of human and animal waste in most part of the metropolis predispose the masses to infection. Antibiotic therapy is used mainly in our medicare system. It was therefore necessary to examine the antibiotic sensitivity pattern of the most commonly abused antibiotics to this pathogen of emerging significance and the plasmid profile. METHOD: Escherichia coli 0157:H7 strains were isolated from clinical specimens, cattle and commonly used water sources. They were identified using biochemical and serological methods. Antibiotic susceptibility pattern of the strains was done using the disc diffusion method. Plasmids were detected, extracted and the profile assessed. RESULTS: One hundred and twenty one strains of the E.coli 0157:H7 were isolated from all samples. Eighty six strains (75.44%) were from clinical samples, 7 (17.5%) from cattle and 28 (24.56%) from river and stream water. They showed multiple antibiotic resistance to tetracycline, amoxicillin and vancomycin. They were however sensitive to ofloxacin and ciprofloxacin. Plasmids were detected in twenty strains (16.5%) and the sizes ranged from 0.564 kb to > 23.13 kb. CONCLUSIONS: The presence of a large number of antibiotic resistant strains of this pathogen in our environment poses serious health risks. It is important that further work is on-going to find out if the antibiotic resistance is plasmid mediated. The development of antibiotic resistant strains amongst these animals poses serious health risks most especially because of the problems of resistance transfer to humans.