A, H. pylori is the culprit of gastric disease A large number of studies have confirmed that H. pylori is the highest human infection bacteria, the infection rate in the population of gastric disease up to 70% to 90%. H. pylori is the main cause of ulcer disease and gastritis, but also a class of gastric cancer carcinogenic factors, timely diagnosis and eradication of H. pylori is a prerequisite for the cure of gastric disease, and the onset of halitosis, lymphoma, allergic diseases, etc.. Second, the transmission of H. pylori infection H. pylori infection is the main source of infection. The main transmission routes are: oral-oral transmission, fecal-oral transmission, medical transmission and close contact. It has been reported that H. pylori infection is aggregated in kindergartens, nurseries, troops and family clusters.