A regimen that combines serum and recombinant hepatitis B vaccines may not produce as high an antibody level as three doses of the same vaccine. Those who began immunization with serum vaccine and concluded with recombinant vaccine should be monitored for an accelerated drop in serum antibodies.

A regimen that combines serum and recombinant hepatitis B vaccines may not produce as high an antibody level as three doses of the same vaccine. Those who began immunization with serum vaccine and concluded with recombinant vaccine should be monitored for an accelerated drop in serum antibodies.