Tino Deng, from the University of Nairobi’s Department of Veterinary Pathology, and his team recently tested chicken meat from three different sources in Nairobi for the presence of E. coli and its resistance to antibiotics. Their findings revealed that some chicken sold in Nairobi is contaminated with E. coli strains resistant to critical antibiotics, which could pose a health risk if the meat is undercooked or improperly handled.
E. coli, a bacterium commonly found in the intestines of both humans and animals, can cause various illnesses, including pneumonia, urinary tract infections, and diarrhea if ingested. Deng and his colleagues tested chicken from three sources: sick birds from a veterinary clinic, farm chickens, and those from Nairobi’s poultry markets. They collected swabs from the anal openings of the chicken carcasses and tested them for E. coli, as well as for resistance to eight commonly used antibiotics, including ampicillin, tetracycline, and gentamicin.
The results, published in Veterinary Medicine International, showed that 31.4% of the samples were contaminated with E. coli. Resistance levels were highest in chickens from the veterinary clinic, followed by farm chickens, and the lowest in market chickens. The bacteria exhibited significant resistance to multiple antibiotics, with the most common being ampicillin (85.22%), tetracycline (66.7%), co-trimoxazole (57.4%), and streptomycin (40.7%).
Interestingly, resistance was lower for nalidixic acid (24.1%) and chloramphenicol (14.8%), while amoxicillin and gentamicin had the lowest resistance rates, with over 96% susceptibility. The study also highlighted that over 81% of the E. coli isolates were resistant to multiple antibiotics, indicating widespread multidrug resistance. Some isolates were resistant to up to six different antibiotics, with ampicillin being the most common drug found in multidrug-resistant combinations.
The researchers suggest that the overuse of antibiotics in livestock farming, particularly as growth promoters or preventive measures, contributes to the development of antibiotic resistance. This issue is not limited to Kenya, but due to limited surveillance, understanding the full extent of resistance remains challenging.
The study also pointed to potential environmental contamination from human and animal movement, faecal contamination, and improper disposal of medicines as contributing factors to the spread of resistant bacteria.
