Objective: There are 5.1-6.5% of people with positive anti-HBc in Iran. The aim of this study was to assess the predicting factors of response to hepatitis B vaccination in anti-HBc positive subjects.
Results: Total response rate to vaccination was 79.8% (75 cases) and 67.9% (38 cases) in cases and controls, respectively. Nineteen persons (20.2%) in cases and 18 persons (32.1%) of controls had negative anti-HBs even after three doses of HB vaccination. Factor associated with decreased response to vaccination was prior history of being HBsAg positive (OR = 1.3, p = 0.01).
Methods: In a quasi-experimental study, 94 people with negative HBsAg, negative anti-HBs and positive anti-HBc (cases) and 56 persons with negative HBsAg, anti-HBs and anti-HBc (controls) were vaccinated at zero, one and six months with recombinant hepatitis B vaccine. Successful immunization was defined by anti-HBs antibody titer > or =10 mIU/mL.
Conclusion: The rate of response to hepatitis B vaccination is nearly like other studies but somewhat different. Higher percent of married cases together with higher percent of positive HBsAg in spouses may explain the slight difference in the response to vaccination in cases in comparison with controls as a result of booster like effect that seldom happens because of recurrent contacts between the subjects and the HBsAg positive spouses spontaneously.