Helicobacter pylori bacteria

Helicobacter pylori bacteria are spiral-shaped organisms that colonise the mucus layer of the stomach and cause a chronic gastric infection. Infection is common worldwide, especially where income is low, and is usually acquired in childhood through contact with faeces, saliva or vomit, or through contaminated food and water; crowding, poverty and poor sanitation raise the likelihood. Most carriers have no symptoms, but persistent infection can inflame the stomach lining and lead to gastritis, peptic ulcer, and less often gastric cancer or a rare stomach lymphoma. Ulcer symptoms include burning stomach pain, bloating, nausea and weight loss. Blood, breath and stool tests detect the organism, and endoscopy may be added. Treatment combines antibiotics with acid-reducing medicines, followed by repeat testing to confirm eradication; no vaccine exists.

Seek urgent care for vomiting blood, black or bloody stools, severe abdominal pain, or difficulty swallowing. See a doctor for heartburn more than twice a week, a change in bowel habit lasting more than three weeks, or unexplained weight loss. Call the local emergency number for any symptom that is sudden and severe. This page is a reference for healthcare professionals and does not replace an assessment.