illness can also be caused by C. coli (also found in cattle, swine, and birds), C. upsaliensis (found in cats and dogs) and C. lari (present in seabirds in particular). One effect of campylobacteriosis is tissue injury in the gut. The sites of tissue injury include the jejunum, the ileum, and the colon. C jejuni appears to achieve this by invading and destroying epithelial cells. C. jejuni can also cause a latent autoimmune effect on the nerves of the legs, which is usually seen several weeks after a surgical procedure of the abdomen. The effect is known as an acute idiopathic demyelinating polyneuropathy (AIDP), i.e. Guillain–Barré syndrome, in which one sees symptoms of ascending paralysis, dysaesthesias usually below the waist, and, in the later stages, respiratory failure. Some strains of C jejuni produce a cholera-like enterotoxin, which is important in watery diarrhea observed in infections. The organism produces diffuse, bloody, edematous, and exudative enteritis. In a small number of cases, the infection may be associated with hemolytic uremic syndrome and thrombotic thrombocytopenic purpura through a poorly understood mechanism. Transmission The common routes of transmission for the disease-causing bacteria are fecal-oral, person-to-person sexual contact, ingestion of contaminated food (generally unpasteurized (raw) milk and undercooked or poorly handled poultry), and waterborne (i.e., through contaminated drinking water). Contact with contaminated poultry, livestock, or household pets, especially puppies, can also cause disease. Animals farmed for meat are the main source of campylobacteriosis. A study published in PLoS Genetics (26 September 2008) by researchers from Lancashire, England, and Chicago, Illinois, found that 97 percent of campylobacteriosis cases sampled in Lancashire were caused by bacteria typically found in chicken and livestock. In 57 percent of cases, the bacteria could be traced to chicken, and in 35 percent to cattle. Wild animal and environmental sources were accountable for just three percent of disease. The infectious dose is 1000–10,000 bacteria (although ten to five hundred bacteria can be enough to infect humans). Campylobacter species are sensitive to hydrochloric acid in the stomach, and acid reduction treatment can reduce the amount of inoculum needed to cause disease. Exposure to bacteria is often more common during travelling, and therefore campylobacteriosis is a common form of travelers' diarrhea. Diagnosis Campylobacter organisms can be detected by performing a Gram stain of a stool sample with high specificity and a sensitivity of ~60%, but are most often diagnosed by stool culture. Fecal leukocytes