Prevalence of Multidrug-Resistant Escherichia coli O157:H7 in Poultry Faeces from Live Bird Markets in Lagos, Nigeria

Escherichia coli (E. coli), a gram-negative bacterium, is a major concern for human and animal health. While most E. coli strains are commensal, some can become dangerous pathogens causing intestinal and systemic illnesses. Poultry meat is a potential source of infection; as resistant E. coli can be transmitted to humans through the food chain. This study aimed to determine the prevalence and antibiotic resistance patterns of E. coli O157:H7 in poultry faeces from a live bird market in Lagos, Nigeria. Samples were enriched in TSB (9 mL) at 37 °C for 18–24 h, plated onto EMB and SMAC agar, and presumptive E. coli O157 isolates (non-sorbitol fermenters) were confirmed by latex agglutination, following the manufacturer’s instructions. Antimicrobial susceptibility testing was performed on confirmed E. coli O157 isolates using the Kirby-Bauer disc diffusion method. A total of 180 poultry fecal samples were analyzed. Out of these, 105 (58.33%) were identified as Escherichia coli isolates. The isolation process further revealed that 74 (41.11%) of the isolates were non-sorbitol fermenters, and 26 (14.44%) were confirmed as Escherichia coli O157:H7 using the latex agglutination test. The isolates showed high resistance to most of the tested antibiotics. The findings indicate a high prevalence and a high level of multidrug resistance in E. coli O157:H7 from indigenous chickens in Lagos' live bird markets. The presence of these pathogenic and resistant organisms poses a significant public health risk to individuals with direct contact with the birds and to consumers in Nigeria.