Feces contain intestinal bacteria and exfoliated epithelial cells that may provide useful information concerning gastrointestinal tract health. For example, bacteria activate or metabolize potential carcinogens (Blaut et al., 2006; Knasmuller et al., 2001; Vanhaecke et al., 2006) or can have anti-tumor effects (Fukui et al., 2001) that may have relevance to colorectal cancer, the second most common cause of cancer deaths in the USA. With the gastrointestinal tract being the largest area of the body that is constantly exposed to ingested/digested food and microorganisms, it is conceivable that luminal exposure may play a significant role in the development of colorectal cancer. Campylobacter species were first recognised as a cause of abortion in cattle and sheep, and a cause of diarrhoea in cattle and pigs. They were first isolated from the faeces of humans in the early 1970s. Campylobacter species are now known to be a major cause of enteritis in the developed world, and are the commonest identifiable bacterial cause of diarrhoea in the UK as identified by the second Infectious Intestinal Disease study (IID2). Campylobacters are Gram-negative bacteria which are important animal and human pathogens. Campylobacter is the most commonly identified food-borne bacterial infection encountered in the world. In 2000, approximately 56,000 cases were formally recorded in UK laboratory reports, with as many as 400,000 expected to occur in total.
