Campylobacter (Greek campylo, curved; bacter, rod) are motile, non–spore-forming gram-negative rods. They are a very common cause of gastrointestinal (GI) infection in humans in many parts of the world. Campylobacter organisms were first isolated in the early 1900s from aborted sheep fetuses. However, it was many years later and not until the 1970s that Campylobacter were isolated from stool. There are many members of the genus Campylobacter; the major enteric pathogen for humans is Campylobacter jejuni, although Campylobacter coli, Campylobacter fetus, Campylobacter upsaliensis, and Campylobacter lari are also pathogenic to humans. Campylobacter jejuni is most frequently associated with GI disease, and C. fetus usually causes systemic infection, often in debilitated patients. Campylobacter is microaerophilic, and although all will grow at 37°C (98.6°F), C. jejuni grows best at 42°C (107.6°F). A number of selective media are in use, including Skirrows, Butzler's, and Campy-BAP. Although several serotypes of C. jejuni have been reported, there are few data regarding the relative virulence of these different types, although some appear to be more closely associated with the development of Guillain–Barré syndrome (GBS) than others.

EPIDEMIOLOGY

Campylobacter is one of the most commonly diagnosed enteric bacterial infection in many parts of the United States and Europe. It is estimated that there are more than 2 million cases per year in the United States. It is especially common in children younger than 1 year of age and in young adults, and it occurs most often in the summer.