Seroprevalence of Helicobacter pylori and associated risk factors in Zakho City: a population-based study

Introduction and aims Helicobacter pylori ( H. pylori) is a major contributor to gastrointestinal diseases and gastric cancer worldwide. Despite reports indicating a high seroprevalence of H. pylori in the Kurdistan Region of Iraq, data specific to Zakho City remain limited. This study aimed to determine the seroprevalence of H. pylori infection and to assess associated risk factors in a representative population sample from Zakho City. Methods A community-based cross-sectional study was conducted between 1 February and 1 March 2025. A total of 391 individuals were recruited using a multi-stage random sampling technique of households in the community. Data were collected using a structured self-administered questionnaire that assessed demographic characteristics, hygiene practices, gastrointestinal symptoms, and family history of H. pylori infection. Venous blood samples were obtained from all participants and analyzed for the presence of H. pylori IgG antibodies using standard serological methods. Results The overall seroprevalence of H. pylori was 52.9% (95% CI: 48%–58%). Multivariate logistic regression analysis demonstrated a significant association between age and H. pylori seropositivity (adjusted odds ratio = 1.028; p = 0.022), indicating a 2.8% increase in the odds of infection with each additional year of age. No significant associations were observed with gender, marital status, employment status, household size, source of drinking water, or sanitation practices. Conclusions H. pylori seroprevalence remains high in Zakho City, though at a lower rate than earlier national estimates. The age-related pattern, consistent with a cohort birth effect, highlights the importance of targeted screening and prevention strategies. It should be noted that IgG seropositivity reflects prior exposure and does not indicate the exact age at infection, and the association with age is based on cross-sectional data.