Low-dose hepatitis B vaccination with recombinant vaccine in Iranian health care workers

Background – Hepatitis B and its sequelae are among the most important public health hazards in Iran and other developing countries. Although effective vaccines are available, the high cost of the vaccines has remained an obstacle to their use. The present study was designed in order to evaluate modification of vaccination schemes as a cost-reduction strategy. Methods – The study was a randomized clinical trial in which 182 healthy adults occupied in health care services with no previous exposure to hepatitis B virus volunteered to be enrolled. The subjects were vaccinated with a recombinant HB vaccine using four different vaccination schemes. The rates of seroconversion as well as the levels of anti-HBs titers in the four schemes were compared. Results – Although the seroconversion rate and nonresponsiveness were the same in all of the 4 groups (97.6%, 97.8%, 96%, and 97.2%; p > 0.5), the concentration of anti-HBs was significantly lower in the groups vaccinated intradermally compared to the groups vaccinated intramuscularly (means: 675 vs 3,200 IU/L, p < 0.01). Conclusion – Replacing the second and third injections in the regular scheme of recombinant HB vaccine with two intradermal injections of 2 µg (one-tenth of the regular dose) results in the same seroconversion rates and the same level of anti-HBs as the regular scheme.