Tr. Gunn et Dg. Woodfield, THE PERSISTENCE OF ANTI-HEPATITIS-B SURFACE ANTIBODIES TO 3 YEARS OF AGE - IS A HEPATITIS-B VACCINE BOOSTER REQUIRED, New Zealand medical journal, 106(968), 1993, pp. 499-501
(A)ims. To evaluate the persistence of hepatitis B surface antibodies
(anti-HBs) after immunisation in early infancy. Methods. The infants w
ere born to low risk European mothers negative for hepatitis B surface
antigen (HBsAg). All the children had received 3 doses of 20 mu g of
recombinant DNA hepatitis B vaccine. Results. One month after the thir
d dose all 92 infants were seropositive. The GMT was 1190 mIU/mL and a
ll but one infant had seroprotective titres above 10 mIU/mL. Three yea
rs after the vaccination 91% (59 of 65) children who returned for test
ing still had measurable anti-HBs titres. The GMT was 32 mIU/mL but 26
% (17 of 65) had titres less than 10 mIU/ml. Only one child had serolo
gic evidence of contact with the hepatitis B virus but did not develop
the disease. Conclusion. This vaccine is safe and effective for at le
ast 3 years. The long term duration of protection from vaccination in
early infancy requires further studies.