Immune Response to Hepatitis B Vaccination According to National EPI Schedule among Children Below 2 Years

Background: Hepatitis B virus infection is a public health burden globally. We incorporate Hep-B vaccine in our EPI schedule. There is no comprehensive data regarding the immune response of the HBV vaccine at one year in our country. The study was done to assess the immune response among HBV vaccinated children at this age group. Materials and methods: This cross-sectional study was conducted at EPI outdoor of Chittagong Medical College Hospital from January to December, 2022. Blood sample from 375 vaccinated children were tested for Anti-HBs titre by ELISA technique in between 9 months to 15 months. Statistical analyses were performed with Statistical Package for Social Sciences version 23.0. Results: This study shows that older children and male tend to have better immune responses after vaccination and malnutrition is a significant risk factor for low antibody titers. This study also shows that 79.2% of children had satisfactory or high levels of anti-HBs antibodies (≥10 mIU/mL). However, 20.8% of children had low antibody titers (<10 mIU/mL) indicating inadequate immune protection. Conclusion: Most children vaccinated under the current EPI schedule develop protective immunity against hepatitis B; a small proportion remain vulnerable due to inadequate seroconversion. Key words: Anti HBs; EPI; Hep-B vaccination; One-year><10 mIU/mL) indicating inadequate immune protection. Conclusion: Most children vaccinated under the current EPI schedule develop protective immunity against hepatitis B; a small proportion remain vulnerable due to inadequate seroconversion. Chatt Maa Shi Hosp Med Coll J; Vol.25 (2); July 2026; Page 10-15