RIA evaluation of antibody levels in neonates from HBsAg-positive mothers after active, passive, and combined immunoprophylaxis.
We evaluated the anti-HBs titers in 20 babies born to HBsAg-positive mothers and receiving different programs designed to prevent hepatitis B. Passive prophylaxis by HBIG for 6 months assured detectable antibody levels in the same period. 3 months after the last injection we could detect antibodies in 5 out of 9 cases. In no case could we detect antibodies 6 months after the last dose. Active prophylaxis by hepatitis B vaccine was able to raise anti-HBs response in 8 out of 12 babies after two or three very small doses (1.25 micrograms of antigen). 2 of these babies were given the first dose at birth. Small doses of vaccine were immunogenic in the presence of passive antibodies.
D000914:Antibodies, Viral / Q000032:analysis*; D002353:Carrier State; D005260:Female; D006509:Hepatitis B / Q000276:immunology* / Q000517:prevention & control; D006514:Hepatitis B Surface Antigens / Q000032:analysis; D017325:Hepatitis B Vaccines; D006801:Humans; D007114:Immunization; D007116:Immunization, Passive; D007231:Infant, Newborn; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000276:immunology; D011863:Radioimmunoassay; D014765:Viral Vaccines / Q000008:administration & dosage
D000914:Antibodies, Viral; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines; D014765:Viral Vaccines