Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 46 1 2008 02 15 27 32 A. Jafarzadeh M. Kazemi Arababadi M. Mirzaee A. Pourazar 2015 09 28 Diagnosis of hepatitis B is routinely based on of serological assay of hepatitis B surface antigen (HBsAg). Occult hepatitis B virus (HBV) infection is generally defined as the detection of HBV -DNA in the serum or tissues of subjects who have negative test for HBsAg. Transmission of HBV infection has been documented from HBsAg negative, anti-HBc positive blood and organ donors. The aim of this study was to determine the rate of occult HBV infection among HBsAg negative and anti-HBc positive blood donors of Rafsanjan blood transfusion center. ‎ Sera from 270 healthy blood donors who were negative for both HBsAg and anti-HCV, were tested for anti-HBc antibodies by use of ELISA technique. The samples that were negative for HBsAg but positive for anti-HBc markers also examined for the presence of HBV-DNA by polymerase chain reaction (PCR). ‎ Out of 270 HBsAg negative blood samples, 14 samples (5.18%) were positive for anti-HBc antibodies. HBV-DNA was detected in 4/14 (28.57%) of HBsAg negative and anti-HBc positive samples. Moreover, anti-HBs antibody was detected in 2/4 (50%) of HBV-DNA positive samples. ‎ These results indicated that HBV-DNA found in the majority of HBsAg negative and anti-HBc-positive donors. In addition, the present study recommend the incorporation of routine anti-HBc screening of blood as a surrogate marker of occult HBV infection to prevent some transfusion-transmitted HBV infections. https://acta.tums.ac.ir/index.php/acta/article/view/3437 https://acta.tums.ac.ir/index.php/acta/article/download/3437/3414