Drivers of zoonotic Campylobacter Species transmission in slaughterhouse settings: Insights from Nigeria for global One Health improvement

Slaughterhouse workers (SHWs) face occupational risk of zoonotic <i>Campylobacter</i> infection (ZCI) but exposure data are limited in low- and middle-income countries (LMICs), particularly Nigeria. This study assessed behavioral, educational, and infrastructural factors affecting <i>Campylobacter</i> exposure among 188 SHWs in Enugu, Nigeria. Data on socio-demographics, hygiene practices, knowledge of zoonotic transmission, and self-reported gastroenteritis symptoms were collected via a validated questionnaire. Descriptive statistics and multivariable logistic regression identified determinants of risky practices, knowledge gaps, and symptoms. Overall, 56.4% of SHWs were classified as high-risk for <i>Campylobacter</i> exposure. Unsafe practices included non-use of personal protective equipment (PPE) (77.1%), washing multiple carcasses in the same bowl (54.8%), eating or drinking during processing (45.7%), and consuming raw or undercooked meat (36.7%). Non-potable water was used by 90.4% of respondents, with only 14.1% purifying it. Behavioral practices aiding ZCI were significantly associated with lack of hygiene training (OR = 3.7, 95% CI: 1.7-8.0, <i>p</i> = 0.001), low educational attainment (OR = 2.8, 95% CI: 0.15-0.85, <i>p</i> = 0.020), age ≥ 45 years (OR = 2.1, 95% CI: 0.25-0.92, <i>p</i> = 0.028), and urban slaughterhouse location (OR = 2.4, 95% CI: 1.26-4.57, <i>p</i> = 0.007). Knowledge gaps were common, with 28-57% unaware of transmission risks via meat, water, PPE, or eating during processing. Self-reported gastroenteritis symptoms were documented in 64.4% of SHWs, with 76% continuing work while symptomatic. Having <10 years' work experience (AOR = 2.84, 95% CI: 1.36-5.95, <i>p</i> = 0.006), lack of training (AOR = 2.74, 95% CI: 1.12-6.67, <i>p</i> = 0.027), low knowledge of <i>Campylobacter</i> transmission dynamics (AOR = 4.46, 95% CI: 2.02-9.87, <i>p</i> < 0.001), and high-risk practices (AOR = 6.98, 95% CI: 3.0-16.2, p < 0.001) were independently associated with symptoms. These findings highlight critical occupational exposure, entrenched unsafe practices, and knowledge deficits. Targeted One Health interventions, including provision of potable water, mandatory use of PPE, and context-specific hygiene training are urgently needed to reduce zoonotic <i>Campylobacter</i> transmission risks and enhance food safety in the study area.