Meat-Associated Pathogens of Recent Concern

At one time only recognized as a pathogen of animals, C. iejuni is now known as a leading cause of acute bacterial gastroenteritis in humans throughout the world. A recent study in the United States revealed that C. jejuni was isolated from fecal specimens of patients more often than Salmonella and Shigella combined. Foods of animal origin are a source of many campylobacter infections, with raw milk, undercooked poultry and raw hamburger being implicated as vehicles of transmission in outbreaks of campylobacter enteritis. C. jejuni is a common part of the intestinal flora of many mammalian and avian species, having been isolated from feces of healthy cattle, swine, sheep, goats and poultry. Often, greater than l o 6 C. jejuni are present per gram of animal feces. Surveys of retail meats indicate C. jejuni is present in about 3.5% to 8% of red meat and 30% to 85% of poultry meat. Interestingly, C. jejuni does not survive well outside of its host's environment nor is the organism likely to grow well in foods. However, studies done to determine infectious dose revealed that ingestion of relatively small numbers (a few hundred cells) of C. jejuni can produce illness. The organism's apparent high degree of virulence and its widespread prevalence in animal-derived foods are important factors in explaining why this sensitive bacterium is a leading cause of human enteric infections.