Risk factors for Helicobacter pylori infection in children: an examination of the role played by intrafamilial bed sharing

BACKGROUND: The exact mode of transmission of Helicobacter pylori is yet to be established. Close personal contact among family members appears to be a key factor. The aim of this study was to establish whether sharing a bed or bedroom with an infected family member is an important risk factor for primary childhood H. pylori infection. METHODS: Fifty-two families with at least 1 child (the index case) with H. pylori infection were recruited. The resultant study population comprised 126 siblings of the index cases. H. pylori infection was established by culture or by histology and urease testing on antral biopsies in index cases and by C-urea breath testing in family members. Data regarding sleeping arrangements within the family were collected. RESULTS: Sharing a bed or bedroom with an infected sibling at the age of 3 years significantly increased the risk of childhood H. pylori infection [odds ratio, 4.84; 95% confidence intervals, 1.54-15.20; P < 0.01 and 3.68 (1.26-10.75), P = 0.017, respectively]. In addition, a child was at significantly increased risk of being infected if his/her mother or father was H. pylori-positive [odds ratio, 2.52; 95% confidence intervals, 1.03-6.13], P = 0.042 and 2.99 (1.04-8.61), P = 0.042, respectively). CONCLUSIONS: Sharing a bed or bedroom with an infected sibling in early childhood increases significantly the risk of childhood H. pylori infection. This provides evidence to support horizontal transmission of H. pylori among siblings.