Background Campylobacter is a leading foodborne pathogen posing a significant One Health challenge due to its broad animal reservoirs and serious antibiotic resistance issues. Despite frequent human-animal-environment interactions in Ethiopia, One Health studies on the occurrence and transmission of Campylobacter are crucial but lacking.

Methodology/Principal Findings A cross-sectional study from March 2021 to March 2022 in and around Debre Berhan, Ethiopia, examined Campylobacter occurrence, resistance, and risk factors in poultry and humans using a One Health approach. A total of 366 samples from 122 poultry farms were collected, including cloacal swabs, human stools, and poultry house floor sock samples. Epidemiological data on risk factors and respondents awareness were gathered through face-to-face interviews. Campylobacter spp. were isolated following ISO 10272 and confirmed with multiplex PCR, with antimicrobial susceptibility tested by disc diffusion according EUCAST guidelines. Campylobacter spp. were found in 12.5% of samples, highest in poultry (19.6%), followed by human stools (13.1%) and floor socks (4.9%). Campylobacter jejuni was the dominant species (80.4%), followed by C. coli (19.6%). In poultry, mixed farming with cattle increased Campylobacter colonization odds (adjusted odds ratio; AOR=9.5), while all-in/all-out management decreased it (AOR=8.4). In humans, Campylobacter infection was linked to raw milk consumption (AOR=5.5), poultry access to living areas (AOR=6.3), not using personal protective equipment working with poultry (AOR=8.3) and not washing hands after handling poultry and cleaning barn (AOR=5.6). Farm workers had a significant knowledge gap on zoonotic risks, including Campylobacter and One Health. High antibiotic resistance was observed, especially to erythromycin (63.0%), ciprofloxacin (69.5%), tetracycline (89.1%), and oxytetracycline (73.9%), with 69.5% of isolates showing multi-drug resistance.

Conclusions/Significance The study revealed widespread occurrence of resistant Campylobacter spp. in poultry, workers, and the environment, highlighting the need for One Health interventions, including better biosecurity, hygiene, education, and stricter antimicrobial use to safeguard animal and human health.

Author summary A study conducted in and around Debre Berhan, central Ethiopia, analyzed samples from poultry farms for Campylobacter spp. and their antimicrobial resistance. The highest prevalence of Campylobacter was found in poultry, followed by human and poultry house floor samples. Poor farm biosecurity and management practices were linked to Campylobacter in poultry, while human infections were associated with raw milk consumption and inadequate hygiene practices in poultry farm. The study emphasizes the zoonotic risks of Campylobacter and the need for a One Health approach to address its spread. Campylobacter isolates showed high resistance to common antimicrobials, with many classified as multidrug-resistant. Co-occurrence of C. jejuni in poultry, farm workers, and the environment, all with similar multidrug-resistant patterns, suggests possible transmission between them. These findings underline the widespread antimicrobial resistance in Campylobacter from poultry farms and the urgent need for responsible antibiotic use to control resistant strains. Given the serious implications of antimicrobial resistance, the zoonotic importance of Campylobacter, and the frequent human-animal-environment interactions in Ethiopia, it is crucial to implement a national plan for surveillance, prevention, and control, and along with promoting rational antimicrobial use through a One Health approach

The authors have declared no competing interest.

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Addis Ababa University, Institute of Biotechnology Institutional Review Board.

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