Summary of Workshop
The frequent isolation of gastric helicobacters from many species of animals is of great interest for different reasons: Firstly, isolating a strain of Helicobacter from the stomach can be of clinical significance for the affected animal, if these organisms are able to cause gastritis. Secondly, animal helicobacters may be able to infect humans under selected circumstances, acting as a potential reservoir of human pathogens. Thirdly, gastric helicobacters in animals may represent a viable model for H. pylori-mediated human disease, allowing an understanding of the pathogenesis and possible prevention strategies, e.g. vaccines to be developed. The stage was set by K. A. Eaton, who summarized current knowledge of the field. Three types of helicobacters can be differentiated on the basis of their morphology: H. pylori-like organisms (e.g. H. acinonyx), helicobacters with periplasmic fibrils (e.g. H. felis), and tightly coiled, non-culturable organisms like ‘H. heilmanii’. These organisms may be localized either in the surface mucus layer, or near the parietal cells in the stomach. Histological evidence of chronic gastritis in animals has been found to be almost invariably associated with the carriage of helicobacters, irrespective of the morphological variety or species of organisms present. However, the association with ulcers or clinically significant symptoms in animal hosts is equivocal at best. Therefore, none of these infections may represent a viable model for human disease associated with H. pylori. Two important aspects emerged from the subsequent presentation by G. Cattoli (2–14). Firstly, H. fells can be cultured from a sizeable fraction of dogs but human infections with H. fells are probably rare, therefore pet animals acting as a reservoir for this infection seem rather unlikely.
KeywordsChronic Gastritis Frequent Isolation Viable Model Necrotic Enteritis Surface Mucus Layer
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