Helicobacter pylori (H. pylori) is a type of bacteria that infects your stomach. It can cause sores and inflammation in the lining of your stomach or the upper part of your small intestine (the. H. pylori infections occur across the world due to exposure to saliva or stool in contaminated water or food. Learn how the bacterium is spread and treated with antibiotics. If you're concerned about an H. pylori infection, talk with your healthcare professional. Together you can decide whether H. pylori testing might be right for you. Helicobacter pylori (H. pylori) is a common bacterium that can infect the stomach lining. Most people with H. pylori have no symptoms, but it can cause gastritis or stomach ulcers. Common symptoms can include upper abdominal pain, nausea, and frequent burping. Helicobacter pylori, also known as H. Pylori, is a bacteria that can live in your stomach lining and the first part of your intestine. Nearly half the world’s population has the H. pylori bacteria, though it doesn’t cause problems for most people. Helicobacter infection of the stomach You have been diagnosed with an infection in the stomach caused by bacterium (bug) called Helicobacter pylori (H. pylori). More than half the people in the world may have an H. pylori infection at some point in their lives. These infections often happen during childhood, especially in developing countries. Helicobacter pylori, previously known as Campylobacter pylori, is a gram-negative bacterium best known for its role in infecting the human stomach, often causing gastric ulcers and sometimes stomach cancer. H. pylori (Heliobacter pylori) is a type of bacteria that infects your stomach. It can damage the tissue in your stomach and the first part of your small intestine (the duodenum). In some cases it can also cause painful sores called peptic ulcers in your upper digestive tract. Overview What is an H. pylori infection? H. pylori (Helicobacter pylori) is a type of bacteria that infects your stomach. It’s the most common chronic bacterial infection in humans. It affects more than half of the world’s population. But it doesn’t cause illness in most people.