Varying antibody response in dental health care workers vaccinated with recombinant hepatitis B vaccine.

Significance of the antibody levels to hepatitis B surface antigen (anti-HBs) as an indicator of protective immunity has recently been stressed. The aim of this study was to quantitatively evaluate the immune response in dental personnel vaccinated with Engerix B recombinant DNA vaccine (SK&F). The vaccine was administered to staff at the MEDUNSA Dental Hospital with either no immunity to HBV or with anti-HBs levels below 10 mIU/ml (n = 43). Anti-HBs was determined by AUSAB (Abbott) one, six and seven months after the start of vaccination and expressed in mIU/ml by comparison with a WHO standard. Only 29 per cent of seronegative subjects developed anti-HBs titers of greater than or equal to 10 mIU/ml after the first dose, while 94 per cent reached this level after the third dose. Results indicated that individuals with naturally acquired low anti-HBs were not protected against HBV before vaccination. All subjects previously vaccinated, but with anti-HBs below 10 mIU/ml, reacted with an anamnestic response and were therefore still immune. The overall antibody response after the third inoculation was good, with 95 per cent (41/43) acquiring a protective anti-HBs titer. However 6/43 were low responders with peak anti-HBs levels between 10-100 mIU/ml. Post-vaccination testing and quantitation of the immune response seems strongly advisable, both to identify non- and low responders and to give each vaccine a guideline to further vaccination.