COMPARISON OF 3 DIFFERENT SCHEDULES OF VACCINATION AGAINST HEPATITIS-B IN HEALTH-CARE WORKERS

Health cave workers (HCW) are a group at risk for hepatitis B virus (H BV) infection; as a result, vaccination is recommended. However, eleva ted cost of the vaccination schedule is one of the limiting factors to this approach. Our aim in this study was to evaluate alternative sche dules for vaccination against hepatitis B, in order to obtain safe imm unization with reduced costs. We studied 300 HCW, randomized to be sub mitted to one of three vaccination schedules against hepatitis B: Grou p A-three doses of 20 mu g i. m. (n=103); Group B-first dose i.d. (2 m u g), second and third doses im. (20 mu g) (n=97), Group C-first and s econd doses i.d. (2 mu g), third dose i.m. (20 mu g) (n=100). All indi viduals received recombinant vaccine at 0, 1 and 6 months. After the f irst dose, there was no difference among the three schedules, either i n terms of anamnestic response or in seroconversion rate. After the se cond dose, there was statistical difference among the three schedules (A>B>C), in terms of seroconversion rates. After the third dose, seroc onversion rates were 92.2% in Group A and 92.8% in group B; geometric mean titers (GMT) in Group B (789.6 UI l(-1) were similar to group A ( 1248.0 UI l(-1)). Group C presented a seroconversion rate of 78% and a GMT of 323.0 UI l(-1), both statistically inferior to other schedules . We concluded that the schedule applied in Group B had similar result s when compared to schedule A, with estimated savings of 30% in vaccin e costs. However, a long-term follow-up is necessary to evaluate its c ost-effectiveness.