Hepatitis B vaccine trial in neonates

Abstract

AbstractIn an attempt to interrupt perinatal and postnatal transmission of hepatitis B virus (HBV) infection, hepatitis B vaccine trials were initiated in October 1981 in Taiwan, starting in neonates of hepatitis B e antigen (HBeAg)‐positive hepatitis B surface antigen (HBsAg) carrier mothers and extending to neonates of non‐carrier mothers. All neonates had received a four‐dose schedule of Pasteur plasma‐derived hepatitis B vaccine. Among neonates of HBeAg‐positive HBsAg carrier mothers, the protective efficacy rate of vaccination was 75% in those who received vaccine alone and 90% in those who received vaccine plus hepatitis B immunoglobulin (HBIG) at birth. Among neonates of HBeAg‐negative HBsAg carrier mothers, the protective efficacy rate was 100% whether they had received vaccine alone or vaccine plus HBIG at birth. The protective efficacy rate was also 100% in neonates of non‐carrier mothers. During 6–9 years of long‐term follow‐up, 12 (6%) responsive vaccinees of HBeAg‐positive carrier mothers, one (2%) child of HBeAg‐negative carrier mothers and one child (0.4%) of non‐carrier mothers had seroconverted to antibody to hepatitis B core antigen (anti‐HBc) positivity. ‘Natural booster’ phenomenon, defined as a spontaneous sharp rise in serum antibody to HBsAg (anti‐HBs) titres in the absence of anti‐HBc and HBsAg, was observed in 7% of vaccinees whose mothers were HBeAg‐positive, 6% of vaccinees whose mothers were HBeAg‐negative HBV carriers, and 8% in vaccinees of non‐HBV carrier mothers. None of the responsive vaccinees had seroconverted to HBsAg. Thus, in the first decade of life, the protective efficacy in neonates who responded to plasma‐derived hepatitis B vaccine was 100%.