Detection of HBV DNA in HBsAg Negative

Background: The risk of infection by transfusion-transmitted viruses has been reduced remarkably. However, a zero-risk blood supply is still desirable. The screening for antibody to HBc (anti-HBc) has been shown as an alternative test for the detection of HBV infection. Objective: The main aim of this study was to evaluate HBV infection markers and the potential value of anti-HBc testing of blood donors to detect HBV infection. Methods: In this descriptive cross-sectional study, 545 blood samples were collected and tested for HbsAg using ELISA method. Then all HBsAg negative samples were tested for anti-HBc by the same method. To detect HBV infection, all HBsAg negative and anti-HBc positive samples were tested by PCR for HBV DNA. Results: All blood samples were HBsAg negative of which, 43 (8%) were anti-HBc positive. From those which were positive for anti-HBc, five samples were also positive for HBV DNA. Conclusion: Occult HBV infection is a clinical form of HBV infection in which HBsAg is not expressed by HBV and blood samples cannot be screened by ELISA method, therefore more sensitive techniques are needed. Our results demonstrate that a complementary test such as PCR, for detecting HBV DNA, is essential to ensure safety of blood samples