Antibiotic Resistance of Escherichia coli Isolated from Healthy Food Animals in Kenya

The antimicrobial resistance profile of 204 Escherichia coli isolates of bovine, swine and poultry origin to eight (8) antimicrobial agents was studied. Antimicrobial susceptibility tests were determined using the disk diffusion technique. Full sensitivity to all the eight antimicrobial agents in the test panel was observed in 46 % of all isolates. Resistance to at least one antimicrobial was observed in 10 % of the isolates while multi-drug resistance (two or more antibiotics) was observed in 26 % of the isolates. Generally, resistance was significantly higher for isolates from swine and poultry than in cattle. The overall prevalence was 22 % for sulfamethoxazole, 21 % for co-trimoxazole, 19 % for ampicillin, 14 % for tetracycline, 9 % for streptomycin, 4.4 % for chloramphenicol and 2.5 % for kanamycin. No resistance was observed for gentamycin. It was concluded from the study that healthy food animals form a reservoir of multiple resistant E. coli which may be transmitted to humans through the food chain. Thus, continued surveillance of E. coli obtained from food production continuum is merited to identify emerging antimicrobial-resistant phenotypes. The Kenya Veterinarian Vol. 30 (1) 2006: pp. 23-2