Low-dose intradermal vaccination of medical and dental students.

In 454 medical and dental students who were vaccinated against hepatitis B by means of a low dose (0.1 mL) of serum-derived vaccine, seroconversion rates of 27%, 70% and 89% were obtained after the first, second and third doses, respectively. These figures are comparable with the results that have been reported for the conventional intramuscular schedule, as were the final antibody titres. A fourth intradermal dose boosted the percentage of students who were protected from 82% to 87%. There was a significant variation in the response to different batches of vaccine. This study shows that the low-dose intradermal method is practicable and effective and can be used to achieve great economy in hepatitis B vaccination programmes. The possibility of adding hepatitis B to the present formula of triple antigen should be investigated as a way of extending hepatitis B vaccination to all infants in our community.