Significance of HBV NAT Among HBs Antigen-Negative Blood Donors in Saudi Arabia

Background: Bloodborne hepatitis B virus (HBV) transmission from asymptomatic donors with acute HBV infections who have undetectable surface antigen of HBV (HBsAg), or from donors with chronic infections in whom serological markers were not detected, could cause residual infections leading to relevant transfusion-transmitted infections (RTTIs). HBV nucleic acid testing (NAT) can detect HBV DNA in the HBsAg-negative and total hepatitis B core antibody (anti-HBc)--negative window period of infection and in chronic cases. Objective: To assess the presence or absence of HBV DNA in blood donors with HBsAg negativity. Methods: We collected 3014 blood specimens from volunteer blood donors at the blood bank of King Khalid University Hospital in Riyadh, Saudia Arabia. Specimens from each donor were tested for HBsAg, anti-HBc, and hepatitis B surface antibody (anti-HBs) by commercial immunoassays and for qualitative assessments of HBV-DNA by HBV-NAT testing. Results: Of the 3014 donors, 7 (0.23%) tested positive for HBsAg and anti-HBc, 1 for HBsAg (0.03%) only, and of those 264 donors (8.8%) for anti-HBc. Of these last, 6.9% also tested positive for anti-HBs and 1.9% tested negative for anti-HBs. HBVNAT testing was reactive in 75.0% of subjects who tested HBsAg positive, and nonreactive in 100% of subjects who tested anti-HBc positive/HBsAg negative (with or without anti-HBs). Among 2742 donors who tested seronegative, 1 specimen was determined to be reactive via HBV-NAT testing. Conclusions: The frequency of HBV DNA in blood donors who tested seronegative was low. This finding may indicate the significance of the HBV NAT technique in reducing the residual risk of transfusion-transmitted HBV infection.