Seroprevalence and risk factors of hepatitis A virus infection in Iran: a population based study.

BACKGROUND In older studies, the seroprevalence of hepatitis A virus infection has been reported to be over 95% in Iranians. Most of these studies were performed on volunteer blood donors. Studies on the general population are sparse. The purpose of this study was to determine the current seroprevalence of hepatitis A virus infection in the general population of Iran. METHODS During 2006, 1869 subjects between 18 and 65 years of age were randomly selected from the general population of three Iranian provinces (Tehran, Golestan, and Hormozgan). Subjects were interviewed and a plasma sample was obtained for serologic testing for anti-hepatitis A virus. Univariate and multivariate analysis was performed to identify risk factors. RESULTS The seroprevalence of hepatitis A virus in Tehran, Golestan and Hormozgan was 85%, 99%, and 96%, respectively. The overall seroprevalence of hepatitis A virus in the general population of the three provinces studied was 86% and did not differ between the two genders. The prevalence in younger subjects and in urban populations was under 70%. In multivariate analysis, older age, being married, and level of the father's education was associated with hepatitis A virus seropositivity. CONCLUSION The seroprevalence of hepatitis A virus still appears to be too elevated for recommending routine vaccination in the general population. However, the trend towards a lower prevalence in younger age groups and people from urban areas points towards the possible benefit of vaccination in these subgroups.