[Follow-up on hepatitis B immunized neonates born to HBsAg positive mothers].

OBJECTIVE

To determine the immune persistence in neonates born to hepatitis B surface antigen (HBsAg) positive mothers with different schedules for HB immunization.

METHODS

Two hundred and three neonates born to HBsAg positive mothers were immunized at birth with HB vaccine in different schedules and doses, and followed-up for six years continuously for antibodies against HBs (anti-HBs) and carriage status of HBsAg.

RESULTS

Prevalence of anti-HBs in the neonates kept in more than 90% during the six years since immunization, with a peak at the ages of seven to twelve months and decreasing by 48.82% at the ages of one to two years. Their anti-HBs kept relative stable during two to six years of age. Eight children converted to anti-HBs negative for three to five years still kept uninfected. Fourteen children converted to anti-HBs negative reconverted positive again one to two years later. No single chronic carrier with HBsAg was found in them.

CONCLUSION

A booster dose of HB vaccine seems unnecessary for children in six to ten years after primary immunization.