RESUMO
BACKGROUND: Campylobacter is the most common food-borne pathogen in the European Union. In 2018, the crude incidence rate in Ireland was 63.6 per 100,000 population. Chicken is considered an important source of infection for humans. In 2015, the Campylobacter Stakeholders' Group (CSG) was established to reduce Campylobacter contamination levels in Irish broiler flocks. AIMS: This work aimed to describe the Campylobacter monitoring programme that was established by the CSG, to analyse the results of this testing between 2019 and 2022, and to assess progress. METHODS AND RESULTS: This paper describes the monitoring programme that was established by the CSG, which harmonized Campylobacter enumeration testing across all Irish broiler processors and allowed comparability of results for trend analysis. An analysis of the 2019-2022 data is presented here and compared to previous studies of Campylobacter levels in Irish broilers. An analysis of the 2019-2022 data showed a significant reduction in levels in both caeca and neck skin when the results from 2022 were compared to those from 2019 to 2020. Campylobacter spp. were detected in 37% of caecal samples from first depopulation (pre-thin) broilers and 30% of neck skin samples in 2022, with just 4% of carcases (in neck skin samples) with ≥1000 colony-forming units per gram detected in 2022. Campylobacter levels detected in Irish broilers, in the present monitoring programme were less than those reported in previous studies in both caecal and carcase samples, although not directly comparable for statistical significance because of differences in study methods. CONCLUSIONS: The cooperation between stakeholders and regulators of the Irish broiler chicken industry over the past decade has facilitated a coordinated approach to monitoring of Campylobacter levels in broilers, and implementation of control measures. This has enabled a steady reduction in the levels of Campylobacter in Irish chicken.
RESUMO
In 2008, an EU wide baseline survey of broilers revealed a high Campylobacter prevalence. To assist with industry-wide controls, updated data were required. The primary objective of this study was to establish up-to-date data on Campylobacter carriage and carcass contamination in Irish broilers. Monthly samples were collected from the three largest broiler processing plants in Ireland over a twelve-month period. Samples were taken from both first and final thin birds (partial and full depopulation) from 358 batches of broilers. From each batch, a composite sample of 10 caecal contents (n = 358) and 5 neck skins (n = 1790) were collected and numbers of Campylobacter in each sample were determined. Of the 1790 neck skin samples tested, 53% were Campylobacter positive. Campylobacter was detected in the caecal contents of 66% of all batches tested. Depopulation and/or age had a significant effect on Campylobacter prevalence with 67% of final thin broilers yielding Campylobacter-positive neck skin samples in contrast to 38% of first thin broilers that yielded positive neck skin samples (P ≤ 0.002). A significant seasonal variation was observed in the rate of Campylobacter-positive caecal samples with higher prevalence seen in July (85%) than the colder months of November (61%), December (50%), January (61%) March (57%) and April (59%). Neck skin samples were 7 times more likely to be Campylobacter positive if the caecal contents from the same batch were positive (odds ratio = 7.1; P ≤ 0.0001). The decrease in Campylobacter prevalence observed in neck skin and caecal contents demonstrates the improvements and progress made in reducing prevalences of this important enteropathogen in the Irish poultry industry since the 2008 EU baseline survey. It also provides further supporting data on the impact of thinning, the processing environment and season on Campylobacter prevalence.