Low Prevalence and Incidence of Helicobacter pylori Infection in Children: A Population-Based Study in Japan

BackgroundInfection of Helicobacter pylori mainly occurs in childhood. In Japan, incidence of gastric cancer is still high in the senior citizen population, but little is known about the current H.pylori infection status among children or their family members. MethodsAs a population-based study, the prevalence of H.pylori infection and change in infection status over a 1-year interval in children were determined. Family members of some participants were also invited to participate in the study to determine their infection status. All children of specific ages attending 16 schools in Sasayama, Hyogo Prefecture, were invited to participate. H.pylori infection was determined by the stool antigen test and diagnosis confirmed by polymerase chain reaction and the urea breath test. ResultsHelicobacter pylori prevalence was 1.9% among 689 children aged 0-8years in 2010 and 1.8% among 835 children aged 0-11 in 2011. No feco-conversion was observed in 430 children aged 0-8years (170 were aged 0-4years) who provided follow-up stool samples after 1year. The prevalence of infection was 6% (2 of 33) and 38% (6 of 16) in mothers of negative and positive probands (p=.04), respectively, and 12% (3 of 25) and 50% (8 of 16) (p=.01), respectively, in fathers. ConclusionHelicobacter pylori prevalence in Japanese children is approximately 1.8%, which is much lower than that reported in Japanese adults. New infection may be rare. Parent-to-child infection is thought to be the main infection route of the infrequent infection for children in Japan.