Transmission and acquisition of Helicobacter pylori infection: evidences and hypothesis

The role of Helicobacter pylori in gastroduodenal diseases has been established, but many ecological and epidemiological features remain unclear. Although H pylori infection is one of the most common infections in the world, the mode of transmission remains unknown. Uncommon extra-endoscopic isolation raises obstacles to a good understanding of epidemiological patterns, and no rational basis exists for a prophylaxis strategy. This work reviews the data on the reservoir of the bacteria and its ecological niche, the method of excretion from the site of infection and the possible circumstances of acquisition. Many features are completely unknown or still controversial, and interpretation is often speculative. At the present time, it can be assumed that the most likely mode of spread would be from saliva in childhood. However, further works are required to establish, whether or not, fecal transmission co-occurs in low hygiene conditions.