[Antibodies against hepatitis B virus core antigen among blood donors].

The prevalence of antibodies to the hepatitis B virus (HBV) core antigen (anti-HBc) and the risk factors are evaluated in different blood donor groups. In 1998, on 12,456 first donations, 163 (1.31%) were positive with the two anti-HBc screening tests. Samples were from 69 women (42.3%) and 94 men (57.7%). Three subjects had no anti-HBs but were anti-HBc IgM negative. Forty (24.5%) donors were born in another country than France, and the majority (25 donors, 62.5%) were from North Africa. HBV vaccine had been previously given in 14 subjects (8.6%). Eight (4.9%) had hepatitis before the first donation. Trips in endemic areas (Africa and Asia) were taken by 26 subjects out of 76 donors with follow-up. Two (2.6%) had been previously transfused and six (7.9%) had contact with HBV-infected people. Among 78,033 repeat donations, 26 were positive with the two Anti-HBc screening tests (0.033%). Sixteen were negative after a second test and were probably false positive. Among the ten last donors, nine were Anti-HBs positive. One had anti-HBc IgM and had been recently infected by HBV. The prevalence of Anti-HBc in first-donation persons remains low. Trips in endemic areas and contact with an HBV-infected subject are the most frequent risk factors. Lastly, HBV seroconversion in repeat blood donors is a rare event. Anti-HBc screening in transfusion remains limited.