Objective: The hepatitis B vaccine was first introduced into the routine immunization program in Henan Province, China in 1992. In 2012, a survey was conducted to evaluate the protective effects of hepatitis B vaccination for the populations born during the preceding 15 years.
Methods: A multistage stratified random cluster sampling method was used to collect samples. The participants were interviewed and relevant information was obtained for the population aged 1 to 14 years using a standardized questionnaire; a 2- or 3-ml serum sample was taken from each participant to measure hepatitis B surface antigen (HBsAg) and hepatitis B core antibody (anti-HBc). Association and logistic regression analyses were conducted to determine relationships between these parameters.
Results: A total of 13,207 residents aged 1 to 14 years residing in 60 villages or communities in Henan, China were surveyed and had their blood collected. Serological analysis revealed that the HBsAg and anti-HBc prevalences were 0.8% and 2.6%, respectively. The HBsAg prevalence among children under 5 years of age was 0.5%, showing a decline of 96% compared to the average national HBsAg prevalence in 1992. Children had a higher likelihood of HBsAg positivity if they had an HBsAg-positive family member (odds ratio (OR) 4.26), no history of vaccination (OR 2.06), were born in a smaller township hospital or at home (OR 1.61), were aged 10-14 years (OR 2.07), or were living in a rural area (OR 2.01).
Conclusions: The HBsAg prevalence rate in persons under 15 years of age has dropped significantly in Henan Province after two decades of vaccination. Thus millions of chronic HBV infections have been prevented.
Keywords: Henan; Hepatitis B; Immunization; Serosurvey.
Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.