An infection with Helicobacter pylori is the main cause of the development of gastric and duodenal ulcers, which was wrongly explained with "stomach acidity" before the discovery of the microbe.
Around 50% of all people worldwide are infected with Helicobacter pylori, whereby this microbe colonization can trigger gastritis, which is the case with about 10% of all people with "Helicobacter pyrolis present in the stomach".
Pathways of infection are bacterially infected objects, water, food, etc., whereby protection is only possible through appropriate hygiene.
In China, 60% of all adults and approximately 30% of all children are said to be infected with Helicobacter pylori. The longer an infection persists, the more likely it is that an appropriate gastric disease will break out.