ABSTRACT
Based on RNA sequence studies, the family Campylobacteriaceae is comprised of 16 species and six subspecies of Campylobacter, six species of Helicobacter and three of Arcobacter species. All are enjoined by being microaerophilic, Gram-negative, motile, curved rods. C. jejuni, C. coli, and C. fetus are the most common Campylobacter isolates associated with diarrheal illness and septicemia, while H. pylori has been solidly linked to peptic ulcer disease and gastric carcinoma. The primary reservoirs for campylobacters are animals (cattle, pigs), especially poultry, from which human infections occur through contaminated food or water, or by ingestion of unpasteurized milk. Outbreaks have occurred in association with consumption of chicken or raw milk as well as from contact with infected cats and dogs. Drinking untreated water from rivers and streams in rural areas where animal contamination occurs is also a major route of acquisition.
