How It Spreads
H. pylori passes from person to person, most often within families and households, through saliva, vomit, or stool, and through contaminated food or water. Infection rates are higher where sanitation is limited, and most infections are picked up in childhood and persist silently for decades unless treated. There is no vaccine, but good hand washing and careful food and water handling reduce spread within a household, and reinfection after successful treatment is uncommon in adults.Symptoms and Related Conditions
Most people with H. pylori have no symptoms at all. When the infection causes trouble, it does so mainly through inflammation and ulcers:- Gastritis: H. pylori is the most common cause of chronic gastritis, inflammation of the stomach lining.
- Peptic ulcers: Together with NSAID use, H. pylori accounts for the great majority of peptic ulcer disease. Typical symptoms include gnawing or burning upper abdominal pain that may change with eating, bloating, nausea, early fullness, and loss of appetite.
- Iron and B12 problems: Long-standing infection can contribute to iron-deficiency anemia and reduced vitamin B12 absorption.
- Stomach cancer risk: Decades of untreated infection modestly increase the risk of stomach cancer, which is one reason confirmed infections are treated even when symptoms are mild.
Diagnosis
Testing is recommended for people with ulcers, ongoing dyspepsia, unexplained iron-deficiency anemia, or a family history of stomach cancer. Accurate, noninvasive options include:- Urea breath test: You drink a special solution and breathe into a collection device; the bacterium's enzyme activity is detected in your breath.
- Stool antigen test: Detects H. pylori proteins in a stool sample.
- Endoscopic biopsy: When an upper endoscopy is being done anyway, small samples of the stomach lining can be tested directly.
Treatment
H. pylori is curable, but no single drug eliminates it — treatment always combines medications for about two weeks:- Combination therapy: A proton pump inhibitor such as omeprazole plus two or more antibiotics — commonly amoxicillin with clarithromycin, or regimens using metronidazole; bismuth-based four-drug regimens are another first-line choice, especially where antibiotic resistance is a concern.
- Finish every dose: Stopping early is the main reason treatment fails and encourages resistant bacteria. Side effects such as a metallic taste or loose stools are common but usually mild and temporary.
- Confirm the cure: A repeat breath or stool test at least four weeks after finishing antibiotics verifies the infection is gone; persistent infection is retreated with a different regimen.