Molecular epidemiology and genetic relatedness of zoonotic Campylobacter species from human and food-producing animal sources in Enugu State, Nigeria

Food-producing animals are key reservoirs of zoonotic Campylobacter species, mainly C. jejuni and C. coli, causing human gastroenteritis and animal reproductive issues. Epidemiological data on these pathogens in Nigeria are scarce, limiting control efforts. This study reports the first molecular epidemiology and clonal analysis of Campylobacter from humans and animals in Enugu State, Nigeria. Isolates were obtained using standard microbiological methods. Molecular identification employed conventional PCR, while genetic relatedness was assessed via ERIC-PCR. Campylobacter coli (61.1%) was the predominant species isolated in this study. The overall prevalence of Campylobacter species infections (CSI) was 18.5% (224/1,212). The host-specific prevalence were 16.5% (67/406), 20.4% (85/416) and 18.5% (72/390) for slaughtered cattle, poultry, and humans, respectively. In slaughtered cattle, CSI was significantly [χ² (1) = 5, p = 0.032] associated with seasons but not with breed, age, sex and location. The infection was significantly [χ² (1) = 8.9, p = 0.003] higher in broilers (26.2%, 56/214) when compared to other poultry types. Human CSI was higher in those aged ≥ 18 years (19.9%, 48/241), males (20.5%, 34/166) and slaughterhouse workers (25.2%, 26/103). In children, Campylobacter infection was prevalent in males (23.8%) than in females (10.5%). In pregnant women, CSI increased with both age and parity levels. The prevalence of Campylobacter infections was significantly higher (P < 0.05) during the rainy/wet season than in the dry/hot season in all three species studied. The ERIC-PCR fingerprinting provided evidence of inter-species and geospatial genetic relatedness in the 20 C. coli isolates tested. The findings warrant a One Health control approach against CSI in Enugu State, Nigeria, to mitigate the potential public health and socioeconomic consequences.