H. pylori often infect your stomach during childhood. While infections with this strain of bacteria typically don’t cause symptoms, they can lead to diseases in some people, including peptic ulcers, and an inflammatory condition inside your stomach known as gastritis.
H. pylori are adapted to live in the harsh, acidic environment of the stomach. These bacteria can change the environment around them and reduce its acidity so they can survive. The spiral shape of H. pylori allows them to penetrate your stomach lining, where they’re protected by mucus and your body’s immune cells are not able to reach them. The bacteria can interfere with your immune response and ensure that they’re not destroyed. This can lead to stomach problems.