Helicobacter pylori is a gram-negativebacterium that lives inside the mucus lining of the stomach. It belongs among the proteobacteria. Many gastric ulcers are caused by H. pylori infection, although most humans are infected and not all infections lead to symptoms. Two strains of H. pylori have been sequenced.
... from 18 to 24, 28.0% from 25 to 44, 25.8% from 45 to 64, and 17.2% who are 65 years of age or older. The median age is 41 years. For every 100 females there are 92.6 ...