Campylobacter jejuni is a Gram-negative bacterium. It is one of the most common causes of food poisoning in Europe and in the United States. The vast majority of cases occur as isolated events, not as part of recognized outbreaks.
C. jejuni is commonly associated with poultry, and it naturally colonises the digestive tract of many bird species. All types of poultry and wild birds can become colonized with Campylobacter. It is also common in cattle, and although it is normally a harmless commensal of the gastrointestinal tract in these animals, it can cause campylobacteriosis in calves. It has also been isolated from wombat and kangaroo feces, being a cause of bushwalkers’ diarrhea.
Contaminated drinking water and unpasteurized milk provide an efficient means for distribution. Contaminated food is a major source of isolated infections, with incorrectly prepared meat and poultry as the primary source of the bacteria. Surveys show that 20 to 100% of retail chickens are contaminated.
In contrast to Salmonella, humans do not get infected by consuming eggs.
In most people who become ill with campylobacteriosis, symptoms develop within two to five days of exposure to the organism and illness typically lasts seven days following onset. Infection with C. jejuni usually results in enteritis, which is characterised by abdominal pain, diarrhea, fever, and malaise. Diarrhea itself can vary in severity from loose to bloody stools. The disease is usually self-limiting.
Possible complications of campylobacteriosis can include cholecystitis, pancreatitis, peritonitis, and massive gastrointestinal hemorrhage. Extraintestinal manifestations of Campylobacter infection are quite rare and may include meningitis, endocarditis, septic arthritis, osteomyelitis, and neonatal sepsis. Serious systemic illness caused by Campylobacter infection rarely occurs. Most often, the symptoms of reactive arthritis will occur up to several weeks after infection.