Gunn T R, Woodfield D G
Department of Paediatrics, National Women's Hospital, Auckland.
N Z Med J. 1993 Nov 24;106(968):499-501.
To evaluate the persistence of hepatitis B surface antibodies (anti-HBs) after immunisation in early infancy.
The infants were born to low risk European mothers negative for hepatitis B surface antigen (HBsAg). All the children had received 3 doses of 20 micrograms of recombinant DNA hepatitis B vaccine.
One month after the third dose all 92 infants were seropositive. The GMT was 1190 mIU/mL and all but one infant had seroprotective titres above 10 mIU/mL. Three years after the vaccination 91% (59 of 65) children who returned for testing 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 serologic evidence of contact with the hepatitis B virus but did not develop the disease.
This vaccine is safe and effective for at least 3 years. The long term duration of protection from vaccination in early infancy requires further studies.
