Review – Epidemiology of Helicobacter pylori infection

Abstract

We encompassed recent data related to Helicobacter pylori epidemiology. Infection prevalence was low (50%) in other countries, such as Cameroon, Chile and Bangladesh. Among positive subjects, CagA frequency ranged from ≤33.3% in Japan and Italy to >90% in Chile. In Bulgaria, the infection was frequent (>76%) in children with anemia and weight loss. Huge racial differences in infection prevalence were observed. In the USA, African Americans were 2- and 3-fold more likely to be H. pylori- and CagA-positive than the Caucasians, respectively. Canadian endoscopy patients of Asian/South American origin were 3.8-fold more often infected than the Caucasians. Overall, the infection affected ≥62.0% of diabetics in studies from Europe and Africa and was also more frequent in patients with autoimmune thyroid diseases, arteriosclerosis, glaucoma, osteoporosis and various neurological and skin diseases than in controls. Recent data concerning infection transmission, including H. pylori DNA in oral samples, food, animals, and yeasts were added. H. pylori DNA was found in one-half of vaginal yeasts and one-third of oral yeasts. In addition to the well-known risk factors for the infection, contact with dogs and sheep was reported. Annual recurrence rate of the infection was 0.2-4.8%, although the rate was higher (>18%) in Chinese children. Preservation and variegation of H. pylori genes in numerous American countries were revealed by whole genome sequencing. Briefly, H. pylori infection remains a concern in several countries and in certain subpopulations, as well as in patient groups with some non-gastric diseases.

Keywords

• h. pylori
• epidemiology
• prevalence
• recurrence
• risk factors
• transmission.