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.