A high-resolution investigation of multi-strain Campylobacter infection of European broiler flocks with parallel sequencing.

Abstract T10

Presenter: Frances M Colles (University of Oxford)

Authors: Frances M Colles, Sophie J Hedges, Robert Dixon, Stephen G Preston, Phoebe Thornhill, Kenneth K Barfod, Sabine G Gebhardt-Henrich, Pauline Creach, Ivan Rychlik, Martin CJ Maiden, Marian S Dawkins and Adrian L Smith.

Contaminated chicken meat remains the most common source of human Campylobacter infection in many countries. More detailed knowledge of Campylobacter transmission on-farm is essential to provide better focused interventions for the industry. A total of 54 production flocks in the UK, France, or Switzerland were examined at early (< 8 days of age) or late (> 28 days of age) time points in the production cycle, with up to 16 faecal samples per flock taken. Campylobacter was detected amongst these samples using standard culture or qPCR, 16S bacterial profiling and parallel sequencing of the Campylobacter porA locus. Variants of porA were detected in 34 flocks tested <8 days of age, including samples that were Campylobacter negative by standard culture/qPCR. The percent Campylobacter DNA amongst total bacterial 16S profile was often very small (<0.01%), even amongst samples from older birds that were culture/qPCR positive for Campylobacter. One or two porA variants predominated amongst all samples from a flock that were culture/qPCR positive at slaughter. In contrast, porA variants were more diverse and evenly spread amongst samples/birds that were culture/qPCR negative at slaughter. Parallel sequencing of the porA locus provides a sensitive method of detection for Campylobacter infection. Campylobacter is rarely cultured from commercial flocks < 3 weeks of age, but these results suggest that attention should be focused on younger chicks in order to reduce contamination. Further research is needed to determine why porA variants become dominant in some flocks that become culture/qPCR positive and not others that remain culture/qPCR negative.

About the presenter

I am a professionally qualified microbiologist, having previously worked in NHS microbiology and veterinary diagnostic laboratories. My interest in zoonotic disease lead me pursue a career researching the epidemiology of Campylobacter on farms, and in the human food chain. I work as part of a larger multidisciplinary team in Oxford exploring the interaction between animal health, welfare and behaviour, and the prevalence of infectious disease.

Presenting in Speaking session 3 - Epidemiology and public health