[The long-term efficacy of a recombinant hepatitis B vaccine in newborns].

A prospective evaluation of the immunogenicity, protective efficacy and safety of the recombinant hepatitis B vaccine associated to the immunoglobulin (IG) in newborns with high risk of infection by the hepatitis B virus was carried out. Two groups of newborns were used. The first group was formed by children with HBsAG carrier mothers (56 children) and the second group consisted of newborns of mothers negative for HBsAG, but having a high risk of infection (21 children). Within the first few hours of life, all of the newborns received a dose (20 mcg) or recombinant vaccine and 0.5 ml of IG. New doses of vaccine were administered at one and six months of life. At eight months of age, the anti-HBs seroconversion rate in children belonging to groups 1 and 2 was 100%, with an elevated anti-HBs titer and with no detected cases of positive HBsAG. On a long term basis (39 +/- 5 months), only 5.6% of the children present an anti-HBs titer < 10 mUI/ml. The recombinant hepatitis B vaccine associated to IG is immunogenic and provides efficient protection in newborns. Important side effects were not observed.