ABSTRACT
OBJECTIVE: To assess the immune response of preterm and low birth weight babies (LBW) to hepatitis B (HB) vaccine. SETTING: Neonatal Intensive Care Unit (NICU), postnatal ward and follow up clinics of KEM Hospital, Pune. DESIGN: Open trial. METHODS: 100 babies were enrolled in four study groups. Group I - preterm, gestational age (GA) < 34 weeks; Group II - GA 34 to 36 weeks; Group III full term <2.5 kg (LBW babies); and Group IV full term >2.5 kg (controls). A recombinant DNA HB vaccine was given at 0, 1, 2 and 12 month schedule. The first injection was administered as soon as the neonate was stabilized. Immune response in terms of anti HBs titres (AUSAB EIA Diagnostic kit) was measured one month after each of the first three injections and at the time of one year booster. Adverse events were monitored. RESULTS: 88 and 62 babies completed the study till the third dose and one year booster dose respectively. Immune response of HB vaccine was uniformly good in all the study groups with 100 % sero-conversion after the second dose itself. By one year (i.e. before the booster dose), very high titres were recorded in all 100%, with 85% demonstrating titres >1000 mIU/ml. Preterm and LBW babies had higher GMT as compared to full term babies till one month after third dose. By one year (before booster), full term babies had higher GMT than preterm and LBW babies. However, these differences were not statistically significant. The vaccine was well tolerated and safe and there were no adverse reactions. CONCLUSION: Immune response of preterm, LBW and full term babies to the new generation recombinant DNA HB vaccine was uniformly good. High and long term seroprotective levels were achieved after the second dose itself.