Intrafamilial transmission of Helicobacter pylori: the association between a parent and an offspring with respect to the presence of anti-CagA antibody.

Abstract

In this study, we examined whether the transmission of Helicobacter pylori occurred in married couples. We also examined whether a correlation existed between H. pylori seropositivity in a parent and an offspring, which may be related to H. pylori transmission. A cross-sectional study of residents living in a rural area in Japan was conducted in 1998. The study population consisted of 1910 volunteers, aged from 22 to 79 years, residing in this area. We serologically confirmed the presence of the antigen, CagA (cytotoxin-associated gene A), of H. pylori, using a recombinant CagA antigen, in addition to examining for antibodies to H. pylori, as determined by an IgG-specific enzyme immunoassay. The data were analyzed using logistic regression models. A significant association of H. pylori seropositivity was observed ( P < 0.001) in married couples, but no significant difference with respect to the presence of anti-CagA antibodies was observed in the married couples with H. pylori seropositive results ( P = 0.053). The odds ratio was 8.08 (95% confidence interval [CI], 1.39-40.05) for infection in offspring with seropositive mothers and 2.93 (95% CI, 0.25-33.85) for infection in offspring with seropositive fathers when compared with seronegative fathers or mothers as the reference. There was a concordance between the presence or absence of anti-CagA antibodies in 11 of 13 groups of mothers and offspring (84.6%) compared with concordance in 6 of 14 groups of fathers and offspring (42.9%; P < 0.05). Our results suggest that maternal influence is likely to be more powerful than paternal influence in the transmission of H. pylori.