Objective   To evaluate long-term efficacy of hepatitis B revaccination in non-and hypo-responders.

  Methods   40 non-and hypo-responders diagnosed with severe screening were given three 2-fold-dose boosters(10Lg or 2 μg per dose) randomly by intramuscular or intradermal route, and 80 normal responders diagnosed from the same screening were selected as the controls.A 30-month follow-up was finished after the first booster.

  Results   39 non-and hypo-responders produced protective level anti-HBs, and 64.7% of intramuscular vaccinees and 34.8% of intradermal vaccinees still kept anti-HBs positive at the 30th month.However, the anti-HBs positive rate and the GMT of the antibody positive subjects in non-and hypo-responders were significantly lower than those in normal responders(P < 0.01), and the cumulative HBV infection rate(isolated anti-HBc positiveconversion as infection marker)in non-and hypo-responders was 25.0% (17.6% for intramuscular and 30.4% for intradermal), dramatically higher than 2.6% in normal responders(P < 0.01).

  Conclusion   Intramuscular route was more effective than intradermal route.It is undoubted that revaccination in non-and hypo-responders can improve response to the vaccine and keep protective anti-HBs within a relatively long time, but the efficacy was limited.The final conclusion needed further research with observation on immune memory.