Estimating the prevalence of hepatitis B virus infection and exposure among general population in Iran

Abstract

Context: Accurate and updated data describing hepatitis B virus (HBV) epidemiology is crucial for development of national policies to control HBV infection in each country. This study was conducted to estimate the prevalence of HBV infection and exposure in Iran, using the available provincial data. Methods: MEDLINE, Web of Science, Scopus, Google Scholar, and Scientific Information Database were searched for studies assessing the prevalence of hepatitis B surface antigen (HBs Ag) or hepatitis B core antibody (anti-HBc Ab) among the general population between 2006 and 2016 in at least one city of Iran. National prevalence was estimated by two methods. Method 1 used only prevalence estimates of provinces with available survey data. In method 2, all provinces were classified based on the risk of HBV infection among blood donors. HBV prevalence in provinces with missing data was extrapolated from the provinces with available data, and with comparable risk of HBV infection among blood donors. In both methods, national prevalence was estimated using pooled provincial prevalence estimates, weighted by the province population size. Results: Thirteen studies from 12 provinces were included. The prevalence of HBs Ag and anti-HBc Ab varied markedly across provinces. Provincial HBs Ag prevalence ranged from 0.76% to 5.10% (I-square = 91.7%) and provincial anti-HBc Ab prevalence ranged from 4.17% to 36.90% (I-square = 99.3%). Using method 1, the national prevalence of HBs Ag and anti-HBc Ab was estimated as 1.84% (95%CI: 1.61%, 2.09%), and 13.59% (95%CI: 12.92%, 14.29%), respectively. Using method 2, the national prevalence of HBs Ag was estimated as 1.79% (95% uncertainty range: 1.67%, 1.91%), equating to 1,347,000 (1,253,000 - 1,434,000) individuals living with chronic HBV infection in Iran. The prevalence of HBs Ag and anti-HBc Ab was higher among men compared to women. Conclusions: HBV prevalence in Iran is low, and has decreased over past decades. However, the risk of HBV infection varies across provinces with some provinces having high HBV prevalence. More detailed data of the HBV epidemiology and transmission in provinces where HBV infection is endemic could support designing the appropriate interventions to control HBV epidemics.