Immuneresponse to recombinant hepatitis B vaccination in adults

The present study was conducted to find out the seroconversion following Recombinant Hepatitis B vaccination in healthy adults. Eighty healthy adults (males and females) of age group 18 yrs to 60 yrs were chosen for the study. Their prevaccination blood samples tested negative for HBsAg and Anti HBs antibodies by ELISA test. The subjects were administered 3 doses of recombinant Hepatitis B-(Engerix B) vaccine at 0, 1 and 6 months duration using 20 micrograms of vaccine per dose. Seropositivity (anti HBs titre > or = 10 mIU) after 2 doses was 48.75% and was 91.25% after 3 doses of the vaccine. 8.75% of the vaccinees did not seroconvert. The non responders when further scrutinized did not show evidence of HIV or Hepatitis C infection and they had a normal haemogram and normal immunoglobulins (IgA,IgM,IgG) levels. However 2 such subjects were found to be positive for anti HBc IgG antibodies indicating chances of Hepatitis B infection from a mutant strain of HBV where it is not possible to detect presence of HBs Ag using currently available diagnostic kits.