Helicobacter pylori is a type of bacteria that can live in the stomach lining. It is known to cause various digestive issues, including gastritis and peptic ulcers. Many people infected with H. pylori may not experience symptoms, but it can lead to more serious conditions if left untreated. This bacterium is typically transmitted through contaminated food or water. Diagnosis often involves breath, stool, or endoscopic tests. Treatment usually includes a combination of antibiotics and acid-reducing medications to eliminate the bacteria and promote healing of the stomach lining.