Role of infected parents in transmission of Helicobacter pylori to their children

Aim. Infected parents, especially infected mothers, may play a key role in transmission of Helicobacter pylori within the family. The aim of this population-based study was to determine the role of parental infection status in transmission of H. pylori to the child by taking into consideration the infection status of both parents simultaneously. Methods. Study subjects were a sample of preschool children in the city of Ulm, located in Southern Germany, who were screened for school fitness between January and July, 1998. The infection status of the children was determined by the C-13-urea breath test (UBT). Parental infection status was determined by measurement of specific H. pylori IgG antibodies in saliva using a modified immunoassay (Milenia H. pylori IgG; DPC, Biermann, Germany). The parents provided additional information through a standardized questionnaire. Results. We included 305 children ages 5 to 7 years (mean age, 5.8 years) and their parents in the analysis. Prevalence of H. pylori infection in children by means of UBT was 10.2% [95% confidence interval (CI) 7.0-14.1%]. The prevalence of infection was 5.1% if the mother showed no salivary antibody response against H. pylori and 17.3% if she did. Prevalence of infection in children was 6.8% if the father showed no salivary antibody response and 19.1% if he did. After adjustment for potential confounders (including infection of the spouse), the odds ratio for H. pylori infection of the child was 3.9 (95% CI 1.4 to 10.6) when the mother was saliva-positive and 2.0 (95% CI 0.8 to 5.3) when the father was saliva-positive. Conclusion. This study strengthens previous evidence that in the population studied infected parents, in particular mothers may play a key role in transmission of H. pylori to the child.