[Prevalence of Helicobacter pylori infection in asymptomatic 5-7-year-old children of St. Gallen canton].

The prevalence of Helicobacter pylori infection in asymptomatic Swiss children is not known. The aim of this study was to determine the rate of Helicobacter pylori infection in preschool children of the Canton of St. Gallen, eastern Switzerland. A 13C-urea breath test was performed in 432 randomly selected 5- to 7-year-old children from February to September 1998. A total prevalence of 6.5% was found, with 3.9% for Swiss children and 19.2% for children of parents immigrated from countries or regions with a high prevalence of Helicobacter pylori infection. Children born in these countries and who immigrated later were Helicobacter pylori positive in 70%. In 20/21 brother and sister pairs, the status of Helicobacter pylori infection was concordant. The amount of living space per person and the educational level of parents were comparable for all Helicobacter pylori positive children (Swiss and immigrants). In conclusion, total prevalence of Helicobacter pylori infection in preschool children aged 5 to 7 is low in the eastern part of Switzerland, with a significantly higher rate in children of immigrant parents.