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Background: Hepatitis B infection is a major public health problem worldwide. Given that immune response towards the vaccine is not perfect, we aimed to evaluate circumstances of immune response in vaccinated students.
Materials and Methods: In this study, 219 medical students of Ardabil University of Medical Sciences were recruited, who had been administered vaccine series for the first time, and booster doses after one and six months completely. The serum samples were extracted from whole blood of the participants. The concentration of Hepatitis B surface antigen (HBsAg) and anti-HBs antibody (HBsAb) was measured using a commercial ELISA kit.
Results: It was observed that 201 cases (91.8%) out of 219 cases had positive anti-HBs antibody response, and 18 subjects (8.2%) were nonresponsive cases. Level of HBsAb was significantly different between males and females as well as alcoholics and non-alcoholics. None of the cases was identified as positive for HBsAg.
Conclusion: Considering the results of the present and previous studies in other countries, it can be claimed that the mass vaccination has been effective, especially in medical students.