A study of seroprevalence of Helicobacter pylori determined by ELISA IgG, was conducted in 83 consecutive healthy children. The majority of the children (55%) had the bacterium. Seropositivity was demonstrated in 55% of the age group 0-5 years old, in 47% of 6-10, and in 67%, of the group 11 to 15. Of the children without sanitary inside their homes 86% were seropositive, versus 47% of the children with sanitary in their homes.