Antimicrobial Resistance Determinants in E. coli Isolated from Poultry and Humans at the Poultry-Human Interface in Kano State

This study characterises antimicrobial resistance (AMR) determinants in Escherichia coli isolated from poultry and their human handlers at the poultry-human interface in Kano State, located in Nigeria's North West geopolitical zone. The poultry-human interface, encompassing farm workers, slaughter operators, and live bird market traders, represents a high-risk setting for bidirectional AMR transfer between poultry and human populations. Using a cross-sectional One Health study design, cloacal swabs from 250 poultry birds and rectal swabs from 150 occupationally exposed humans were collected from five live bird markets and three poultry processing facilities in Kano. E. coli was isolated and characterised by antimicrobial susceptibility testing using disc diffusion and MIC determination. Extended-spectrum beta-lactamase (ESBL) production was confirmed phenotypically and genotypically by CTX-M, SHV, and TEM gene PCR. Plasmid-mediated colistin resistance (mcr-1 gene) was screened by PCR. The study provides the first comparative ESBL and colistin resistance data from the poultry-human interface in North West Nigeria. Findings revealed ESBL-producing E. coli in 38 percent of poultry and 22 percent of human isolates, with mcr-1 detected in 14 and 9 percent respectively. Whole genome sequencing showed shared sequence types between poultry and human isolates, suggesting direct resistance element transfer. The study recommends stricter biosafety at live bird markets, antibiotic use reduction in poultry production, and integrated AMR surveillance at poultry-human interfaces. Keywords: antimicrobial resistance, E. coli, ESBL, poultry-human interface, Kano State.