Demographic changes of hepatitis B virus infection in Iran for the last two decades

Aim The objective of this study was to evaluate the impact of the hepatitis B virus (HBV) vaccination program, 24 years after its implementation, by analyzing patients with hepatitis B surface antigen (HBsAg) infection based on gender and age group. Background Since the launch of the first universal vaccination program against HBV in Iran in 1993, the epidemiological pattern of HBV prevalence may have changed in our country. Methods All data for this cross-sectional study were collected from medical records of HBsAg positive patients, who were referred to the Golhak and Armin private laboratories and also to the Gastrointestinal Department of Tehran's Taleghani Hospital and Day Hospital in Iran over a period of 5 years (2011-2016). In total, 8,606 HBsAg positive subjects were assessed according to gender and age group. Results The rates of HBsAg carriage were 0.8%, 7.8%, 49.3%, 27.9% and 14.1% among subjects under 14 years old, 15-24 years, 25-44 years, 45-59 years and those older than 60 years, respectively. According to the age subgroup analyses; the highest (26.2%) and lowest (0.6%) rate of HBsAg positivity was seen in the 31-40 age group and younger than 10 year old children, respectively. Conclusion Global vaccination against hepatitis B has significantly reduced carrier rates among children and teenagers under 20 years old in this country. Nevertheless, HBsAg carriers still remain highly prevalent among 25-35-year age group. Therefore, the decline is limited to the younger population born after 1993, and it remains high in the middle-aged individuals.