Vaccination against hepatitis B in renal dialysis units: short or normal vaccination schedule?

Three I.M. injections of hepatitis B vaccine (Merck Sharp & Dohme) were administered, according to the recommended schedule (0, 1, 6 mos), to seronegative individuals of one renal dialysis unit (33 patients, 58 health care personnel) and, according to a shorter regimen (0, 1, 3 mos), in another unit of similar characteristics (30 patients, 53 health care personnel). Staff members and renal patients received, respectively, 20 y 40 mcg of vaccine per injection. In the early vaccination phase, the two regimens did not lead to a difference in seroconversion rates nor in anti-HBs titers. After a 9-month surveillance, lower seroconversion rates, although not significant, were observed with the accelerated regimen among staff members (84.2%) and renal patients (79.2%) as compared with 93% and 87.5%, respectively, following the normal schedule. At the same time, anti-HBs titers were significantly lower (p less than 0.001) in the staff (316 RIA U) and patients (93 U) vaccinated according to the short regimen than in their respective counterparts (4196 and 1047 U) assigned to the normal schedule. A fourth dose of vaccine given to subjects with low and no anti-HBs titers significantly increased seroconversion and anti-HBs levels, although with little success among the former non-responders.