Campylobacter contamination of chicken meat in Japan: Geographical and Seasonal variations

Chicken is a potent source of human Campylobacter infections. Hence, we investigated the prevalence and antimicrobial resistance of Campylobacter in 440 vacuum-packed chicken breast products during April-December 2021. Campylobacter was isolated from 174 samples (39.5%), in which the mean concentration of Campylobacter was 1.42 +/- 0.65 log(10) CFU/g, and 19.0% of the positive samples contained > 2.0 log(10) CFU/g of Campylobacter. Campylobacter prevalence was significantly (P < 0.01) higher in Western Japan (64.2%) than in Eastern Japan (26.6%). The highest prevalence of Campylobacter in Western and Eastern Japan was observed in August (74.1%) and October (47.8%), respectively. A total of 149 Campylobacter jejuni and 37 C. coli isolates were obtained. C. coli was more frequent among Campylobacter isolated from Western Japan (29.1%) than those obtained from Eastern Japan (6.6%). Among all C. coli isolates, 73.0% and 37.8% were ciprofloxacin- and erythromycin-resistant, respectively. All C. jejuni isolates were susceptible to erythromycin. However, 42.3% of them were ciprofloxacin-resistant. Ciprofloxacin-resistant C. jejuni was significantly (P < 0.01) more frequently in isolates collected from Western Japan than in isolates obtained from Eastern Japan. This study revealed the geographical and seasonal variations in the prevalence of Campylobacter in chicken products. Chicken meat becomes contaminated with Campylobacter while slaughtering Campylobacter-infected broiler flocks in processing plants. Therefore, the development of efficient strategies for decreasing Campylobacter infection in broiler flocks in Western Japan should be prioritized to reduce human Campylobacter infections.