The Role of Helicobacter spp. Infection in Domestic Animals

The discovery of the association of Helicobacter pylori with chronic gastritis, peptic ulcers and gastric neoplasia, mucosa-associated lymphoid tissue-type lymphoma and carcinoma, has led to fundamental changes in the understanding of gastric disease in humans. Some hu‐ mans with H. pylori infection develop only mild, asymptomatic gastritis. Whether more se‐ vere disease develops thought to be influenced by individual host factors and pathogenicity of the bacteria involved. The odd of developing symptomatic H. pylori infection varies by geographic location and age. Different strains of H. pylori have recently been identified. Therefore, H. pylori should be considered a population of closely related but genetically het‐ erogenous bacteria of different genotypes and virulence.