Introduction: Medical Significance of H. pylori

Until the discovery of Helicobacter pylori in 1982, the normal human stomach was generally considered to be sterile, or transiently populated by oropharyngeal bacteria carried there by peristalsis. However, we now know that from one-third to one-half of the human population carries H. pylori , and that once infected, most persons remain infected for decades, if not for life (1 ).