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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: AIMS, METHODS, RESULTS. Meshes: Evaluation Studies as Topic, Female, Hepatitis B Antibodies, Hepatitis B Vaccines, Humans, Immunization Schedule, Immunization, Secondary, Infant, Infant, Newborn, New Zealand, Vaccines, Synthetic.
user
The persistence of anti-hepatitis B surface antibodies to three years of age: is a hepatitis B vaccine booster required? Context: 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.
assistant
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.