Campylobacter in poultry: An elusive pathogen.

Campylobacter in poultry: An elusive pathogen. Campylobacter — primarily Campylobacter jejuni and Campylobacter coli — frequently colonize the intestinal tract of domestic poultry at high levels. The bacterium is well adapted to the avian host and, despite extensive colonization, it produces little or no overt disease in poultry. That makes it difficult to detect and control in live birds. Despite its insignificance for poultry health, Campylobacter is a leading cause of foodborne gastroenteritis in humans worldwide.The poultry reservoir, especially broiler meat, is the most commonly recognized source for human Campylobacter. Campylobacter is, in general, highly prevalent on poultry farms, but the prevalence varies by region, seasons and production types, with reported Campylobacter-positive flocks ranging from 2% to 100%. Once a broiler flock is infected with Campylobacter, the majority of birds become colonized within a few days, and the overall within-flock prevalence reaches very high levels by processing age, leading to increased carcass contamination. A unique feature of Campylobacter ecology in poultry is that birds younger than 2 to 3 weeks of age are almost never colonized by the organism in commercial production settings, which implies that young birds have a biological mechanism for colonization resistance. If the reasons for this colonization resistance are revealed, they could be used to design effective strategies to prevent birds from getting infected.