Prevalence of intrafamiliar diffusion of H-Pylori infection: an epidemiological study

Aim. To investigate the relationship between the prevalence of Helicobacter pylori (Hp) among families of infected children and risk factors within the families, i.e. gastrointestinal diseases, as well as hygienic habits, lifestyles, and behaviour. Methods. The family members (n = 292) of 67 infected children were examined for activeHpinfection through 13C-urea breath test or stool antigen test (HpSA). They were interviewed by questionnaire to obtain information about their living conditions, household habits and clinical history of gastrointestinal diseases. Fisher exact test was used to compare proportions between positive and negative family. Results. Forty-eight families out of the 67 observed (71.6%) showed at least one other infected member. 49.3% of mothers, 54% of siblings and 35% of fathers turned out to be infected. Father’s bed sharing and toothbrush sharing were observed only in “positive family”, respectively, in 31.8% and 20.8% of those family. The factors associated with a significantly increased risk for intrafamilial infection were: being ≤8 years old (p = 0.04); sharing the toothbrushes (p = 0.026) or placing the toothbrushes in the same container (p = 0.057); mother’s low schooling (p = 0.038); sharing the bed with mother (p = 0.014) and with father (p = 0.011). Female sex shows a higher risk of infection (p = 0.036). No significant difference has been detected concerning factors such as nationality, day nursery attendance, crowding, frequent vomiting, smoking, gastrointestinal diseases, and tasting the child’s meal with the same piece of cutlery. Summary. The intrafamilial diffusion of Hp infection in children is related with family lifestyles, age, and mother’s schooling. Conclusions. The Hp infection within the same family is closely linked to family lifestyles and the parent’s role is of primary importance in the matter. The role played by the use to share the toothbrush or to preserve it in the same container may provide helpful guidelines for future prevention strategies, not to mention the increased knowledge concerning transmission of the bacterium.