Campylobacter jejuni Across the Food Chain: Integrating Pathogenesis, Persistence, Antimicrobial Resistance, and Emerging One Health Control Strategies.

Campylobacter jejuni continues to be a globally important foodborne pathogen and is one of the most common bacterial causes of gastroenteritis in humans. This fastidious microaerophilic organism is seldom cultured outside of animal hosts, yet it repeatedly populates poultry, livestock, water, processing environments, retail foods, domestic kitchens, and humans. Here, we critically integrate the evidence in a transmission-connected, farm-to-fork pathway spanning colonization of animal reservoirs and carcass contamination to environmental persistence, human exposure, and disease (including antimicrobial resistance), detection, and intervention. In many systems, asymptomatic, high-density colonization of poultry is the main amplification reservoir and carcass cross-contamination, mixed-species biofilms, aerotolerance, oxidative-stress defense, cold survival, and viable-but-nonculturable cells support persistence through processing and distribution. Coordinated motility, chemotaxis, adhesion, disruption of epithelial barrier functions, invasion, and cytolethal distending toxin activity contribute to epithelial injury and inflammation, whereas lipooligosaccharide-mediated molecular mimicry contributes to postinfectious complications. Factors such as persistent target-site mutations, CmeABC efflux, acquired determinants, and antimicrobial selection within One Health compartments continue to sustain resistance to fluoroquinolones, tetracyclines, and macrolides in certain settings. Because no single point intervention can sufficiently control transmission across the food chain, effective risk reduction relies on a portfolio of components such as whole-farm biosecurity, biological control, hygienic processing and handling, cold-chain management, consumer hygiene interventions at home, antimicrobial stewardship, viability-sensitive detection and genomic surveillance. These findings are consistent with multihurdle control strategies and integrated One Health surveillance linking both animal, food, environmental, and human health sectors. Consequently, future policy and research initiatives should ideally focus on harmonized sampling and surveillance protocols, standardized outcomes of intervention studies, validation at the commercial scale and evidence directly relating C. jejuni reductions to risk of human disease.