An Evaluation of the Responses to the Standard Hepatitis B Vaccination among 8-18-Month-old Children in North East of Iran

Background: Vaccination of children against hepatitis B virus (HBV) is the most effective strategy to prevent infections in their future life. However, the real response to HBV vaccination in infancy is still unclear. The aim of this study was to evaluate the status of immune response to HBV vaccine among children aged 8 to 18 months in east coast of the Caspian Sea, Bandar-e Turkmen, Golestan, Iran. Methods: In this cross-sectional study, 565 children from Bandar-e Turkmen ranging from 8 to 18 months of age, vaccinated in a routine vaccination program were included. The serum samples were collected from all children and HBsAb titers were measured using ELISA. Results: Out of 565 children, 12 (2.12%) had anti-HBs titers <10 IU/L (non-responder) while 553 (97.88%) had anti-HBs titers >10 IU/L (responder) (p<0.05). Among these responder children, 92 (16.3%) had anti-FIBs titers 10-100 IU/L (poor responder) and 461(81.6%) had anti-HBs titers >100 IU/L (good responder). The negative children were revaccinated (3-doses) and 11 of them became protected against HBV infection (anti-HBs titers >10 IU/L). Only 1 of the included children was non-responder, after routine vaccination and 3 doses revaccination. Conclusion: The results of this study indicated that the HBV vaccination program in this region of Iran is effective and most of the children showed positive immune responses after three doses of vaccination. Importantly, revaccination of non-protected individuals is recommended.