Epidemiology of Helicobacter pylori infection in the People's Republic of China.

This paper presents a general review of the studies on the epidemiology of H. pylori infection in China. Among 3,519 dyspeptic individuals presenting for endoscopy, H. pylori detectable rate was 61.2%. A higher prevalence of infection was found in patients with peptic ulcer. The prevalence of gastric metaplasia was 82.5% in patients with duodenal ulcer, 53.1% in duodenitis and 34.5% in normal duodenal mucosa. H. pylori infection is significantly more common in gastric cancer patients (58.9%) than in the matched controls (42.5%). Endoscopic studies performed on asymptomatic volunteers aged 10-25 showed that the prevalence of gastritis and H. pylori was 45%-84% and 42%-67% respectively. Large scale prospective studies of the possible role of H. pylori in gastric cancer in populations with various gastric cancer mortality rates using ELISA assays showed a significant geographical association between gastric cancer mortality and the prevalence of H. pylori infection. H. pylori infection is acquired at an earlier age and has a higher prevalence in the high gastric cancer risk areas than in the low risk areas. H. pylori was detected in human saliva and dental plaque by PCR. H. pylori-like organisms were successfully isolated by culture and detected by nested PCR in the gastric mucosa of pigs and cats. Intrafamilial clustering of H. pylori infection was observed.