Rapid detection of Campylobacter spp. in chickens before slaughter

Campylobacter continues to be the number one cause of bacterial gastroenteritis in Europe. Poultry, and especially broiler chickens, is considered an important reservoir for Campylobacter spp. Poultry producers prioritize to identify and reduce the number of Campylobacter contaminated chicken flocks by tightening biosecurity and mitigation actions at slaughter. Campylobacter-positive flocks must therefore be identified as close to slaughter as possible, and rapid detection methods are needed. Here we evaluated the applicability, sensitivity, and specificity of four commercially available rapid methods to detect Campylobacter in naturally contaminated chicken cecal droppings on-farm before slaughter against an established qPCR method. The Biofire (R) FilmArray (R) Gastrointestinal Panel assay, the VIDAS Campylobacter assay, the Singlepath (R) Campylobacter test, and OptiGenes' Genie Campylobacter isothermal DNA amplification were assessed in a pilot-study. The OptiGenes' Genie Campylobacter isothermal DNA amplification was also tested under field conditions. The Biofire (R) FilmArray (R) showed superior sensitivity and specificity compared to the three other rapid tests but had a lower throughput and a higher cost. While the VIDAS Campylobacter, Singlepath (R) Campylobacter and the isothermal DNA amplification were affordable, their unsatisfactory sensitivity (10%-71%) left these unsuitable to monitor Campylobacter carriage in chickens. An additional finding of this study is that 38% of flocks positive for Campylobacter at slaughter became contaminated during the last week of rearing. Therefore, increased efforts to develop suitable methods to detect Campylobacter rapidly and reliably in chickens close to slaughter are needed.