Helicobacter pylori, musings from the epidemiologic armchair.

The literature on Helicobacter pylori has become enormous, but the epidemiology of the infection remains an enigma. Guided by epidemiologic principles we have tried to interpret the available data on the epidemiologic aspects of H. pylori. We conclude that conflicting results on familial clustering and seroprevalence curves might have logical explanations. However, the exact way this organism spreads among humans remains to be solved.