Hepatitis B Virus Infection; A Vanishing Disease in Iranian Children

Abstract

Hepatitis B virus (HBV) infection is the main cause of chronic liver disease (1) and at least 2 billion people are infected worldwide, while 350 million are chronic HBV carriers (1). The prevalence rate of HBV infection differs in various countries. In areas with a high prevalence (8% or more), the lifetime risk of exposure to the infection is around 60 and it typically occurs in infancy or childhood periods. China, South-East Asia, most of Africa and some parts of the Middle East have a high prevalence of HBV infection and the rate ranges from 8% to 15% (1, 2). Inter-mediate prevalence areas (2-7%) of infection occur across all age groups and most areas of Middle East countries, Eastern and Southern parts of Europe are in this category. There are also areas with low endemicity, i.e. lower than 2% prevalence in adults. These areas include North Amer-ica and Western Europe (1).HBV infection is still the main cause of chronic liver dis-ease in Iran (3), although the seroprevalence of HBV in-fection in Iran has decreased during the last two decades (4). The main risk factor for HBV transmission was pre-viously related to maternal-infantile transmission and high coverage infantile vaccination is the main cause for changes in the epidemiology of HBV infection (5). Given the importance of this interruption to HBV transmission in Iran, the HBV vaccination has been included in the ex-tended program of immunization (EPI) since 1993 (6, 7).Adibi