Hepatitis B viral markers in surface antigen negative blood donors: the need to look beyond antibody negativity.

BACKGROUND The presence of Hepatitis B Virus (HBV) in blood that is Hepatitis B Surface Antigen (HBsAg) negative is considered a potential risk for transmission of hepatitis B virus infection. OBJECTIVE To determine prevalence of antibodies to markers of hepatitis B virus infection in HBsAg negative prospective blood donors. METHODS A structured questionnaire to assess prospective donor's demographic data and past medical history was administered to 457 consenting HBsAg negative subjects. All the subjects were also negative for antibodies to hepatitis C virus (HCV), human immunodeficiency virus (HIV) and syphilis. Their serum samples were tested for the presence of anti-HBc, anti-HBe, anti-HBs and HBeAg. RESULTS Of the 457 samples tested, 20 (4.37%), 58 (12.69%), 1 (0.22%), and 1 (0.22%) were positive to anti-HBc, anti-HBs, anti-HBe, and HBeAg antibodies, respectively. Ten (50%) of those who were positive for HBc antibody were also positive to anti-HBe and anti-HBs. Similarly, two (3.4%) donors who were positive for anti-HBs were also positive for HBeAg and anti-HBe. Of the 20 who were anti-HBc positive, seven had tattoo/traditional marks on their body and one had previous history of blood transfusion. CONCLUSION This study has shown that some potential blood units containing HBV are being transfused to patients unknowingly by screening for HBsAg only. Screening for other markers of hepatitis B virus may increase the rejection rate, but will reduce HBV transmission.