Prevalence of <i>Helicobacter pylori</i> Infection in Children From Households With Members' History of Successful <i>H. pylori</i> Eradication

ABSTRACT Aims This study investigated the prevalence of H elicobacter pylori infection and associated factors in children from households with members' history of successful H. pylori eradication. Methods A cross‐sectional study was conducted from February to December 2024 in Hanoi, Vietnam. Eligible households were those having lived together for at least 12 months, including at least one child under 16 years old and at least one member with successful H. pylori eradication. H. pylori infection status among family members was assessed using stool antigen testing. Data on household demographic characteristics, childcare practices, and infection status of family members were collected. Multivariable logistic regression was used to identify factors associated with infection in children. Results A total of 193 households with 877 members were included, including 338 children under 16 years old. The prevalence of H. pylori infection was 59% overall and 53% among children. Children living with both infected parents had a higher infection prevalence than those with only one infected parent (58% vs. 38.2%, p &lt; 0.001), with a similar trend observed among infected siblings. After adjustment, parental infection status remained the strongest predictor of infection (aOR = 3.18; 95% CI: 1.83–5.52), while larger household size was inversely associated (aOR = 0.74; 95% CI: 0.58–0.93). Conclusions Children's infection risk increased according to the infection status of parents and siblings, while a higher number of family members was associated with a lower likelihood of infection, although this finding should be interpreted with caution, supporting the importance of household‐level transmission and family‐based prevention strategies in high‐prevalence settings.