Helicobacters of possible zoonotic origin: a review

Since the isolation of Helicobacter pylori, many new Helicobacter species have been identified from the gastrointestinal tract in humans and animals. In humans, a spiral organism different from H. pylori and provisionally named "Helicobacter heilmannii", has been associated with gastritis, gastric ulceration and to a lesser degree, gastric cancer. In addition Helicobacter cinaedi, Helicobacter fennelliae, Helicobacter pullorum and "Flexispira rappini" have been isolated from cases of enteric disease, bacteremia and pneumonic illness. In the biliary tract, the presence of Helicobacter bilis, Helicobacter pullorum and "Flexispira rappini" has been demonstrated. Morphological, epidemiological and genotypic data suggest the involvement of animal helicobacters in these infections. In this paper, a review of the literature addressing the current knowledge about epidemiology, diagnosis, pathogenesis and therapy of these infections is given.