Efficacy of Hepatitis B Vaccination among Children in Special Region of Yogyakarta, Indonesia: Evaluation of Humoral and Cellular Immunity.

Hepatitis B remains a global burden, with estimated 15 to 40 percents of infected individuals eventually suffer from liver cirrhosis, liver failure, and hepatocellular carcinoma. Vaccination aims to form anti-HBs antibody with protective titer to prevent infection. CD4 T cell lymphocytes are known to play a major role in establishing immunity after vaccination. This study aimed to investigate protective titer rate among Indonesian children in Special Region of Yogyakarta following hepatitis B vaccination and correlation between anti-HBs titer and CD4 count. This is a cross-sectional study with 52 subjects between 8 months to 5 years of age in Bungas Community Health Service, Special Region of Yogyakarta, Indonesia. Anti-HBs titer was examined using enzyme immunoassay and CD4 count was examined using immunocytochemistry method. Of 52 subjects, median anti-HBs titer was 72.965 IU/L (interquartile range 360.98), mean CD4 count was 49.73% ± 29.75. Protective level of antibody was found in 73.1% of subjects. Correlation test was conducted and no correlation was found between anti-HBs titer and CD4 count (r=-0.104, p=0.464). Age was found to have a weak negative correlation with anti-HBs titer (r=-0.367, p=0.007). We found high rate of protective titer among children in Special Region of Yogyakarta who have completed hepatitis B vaccination series. No correlation was established between anti-HBs titer and CD4 count.