The association of hepatitis A and Helicobacter pylori with sensitization to common allergens, asthma and hay fever in a population of young British adults.

A negative association of oro-faecally spread infection with serological markers of sensitization and allergic disease has been reported. Previous infection with hepatitis A and Helicobacter pylori was assessed in a community-based sample of young British adults and associations with serum-specific IgE to environmental allergens, asthma-like symptoms and hay fever were examined. There was no association of previous infection with hepatitis A or H. pylori with wheeze or hay fever. There was no evidence of an association of infection with either agent and sensitization except for the isolated finding of a lower prevalence of sensitization to grass in those with IgG antibodies to H. pylori (OR 0.65, 95% CI 0.43-0.99). This association did not explain the negative association of family size with sensitization to grass. In this population, there was no evidence that infection with hepatitis A or H. pylori was associated with lower levels of IgE sensitization, asthma or hay fever except for an isolated finding of a negative association of H. pylori infection with sensitization to grass.