Study on Anti-Hepatitis B Surface Antibody Titer and Specific Interferon Gamma Response Among Dentists

Hepatitis B virus (HBV) is a major problem for healthcare workers worldwide, and among them, dentists are at risk of acquiring HBV infection. The prevalence of HBV infection has been reported among the dentists in different regions of the world. Since none of the available drugs can clear HBV infection, the presence of effective immunity against HBV infection is important to prevent HBV infection.
This study aimed at determining HBs antibody and specific HBV gamma interferon among the dentists, who received hepatitis B vaccine.
The blood samples were collected from 40 dentists, including 7 endodontics, 2 oral and maxillofacial radiologist, 4 periodontics, 11 oral and maxillofacial surgeons, 6 implantologists, 3 orthodontics, 1 oral and maxillofacial pathologist, 2 esthetic and restorative dentists, and 4 doctors of dental surgery (DDS) at from dental college of Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran during December, 2013. Overall, 31 (77.5%) dentists had already received 3 doses of recombinant hepatitis B vaccine, and 9 (22.5%) had received only two doses of the vaccine. Their sera were tested for HBsAb and anti-HBc-IgG by the Enzyme Linked Immunosorbent Assay (ELISA) test. The lymphocyte of individuals was separated from their blood sample by Ficoll-Hypaque, cells were washed with phosphate buffered saline (PBS) by centrifugation, and finally the pellet cells was resuspended in RPMI-1640 media. Separated cells were exposed to 2.5 µg of purified recombinant HBs antigen, and supernatants were collected after 72 hours and tested for detection of specific interferon γ level by ELISA test.
Overall, 97.5% of dentists showed positive HBs antibody test results while 36 showed (90%) positive test results for specific interferon γ against hepatitis B virus infection.
High coverage of 97.5% immune response against hepatitis B infection was found, indicating high efficacy of recombinant HBV vaccine among the dentists.