H-pylori resides in the mouth and intestinal tract of fifty percent of the population, and is a recognized cause of ulcers and stomach cancer. H-pylori is a spiral bacterium which can be transmitted from person-to-person, by saliva, food handling, feces, and poor hygiene; and can be acquired by drinking contaminated water or swimming in contaminated water. H-pylori has many strains, and not all strains and not all modes of transmission have been identified. In addition to humans, cats, pigs, sheep, monkeys, and house flies have been implicated as a reservoir for H-pylori.

H-pylori attacks epithelium, burrows beneath the epithelium, and attaches to collagen; and damage from H-pylori is not limited to the stomach and intestine. H-pylori damaged epithelium allows other pathogens to invade deeper into the tissue. H-pylori can attack other abdominal organs, and the eye. H-pylori can cause chronic disease independently, or work with chlamydia and other co-infections, to increase the infectious burden and risk of developing chronic disease.