Follow-up study of anti-hepatitis C virus antibodies in blood donors implicated in post-transfusion non-A, non-B hepatitis.

We retrospectively examined the antibodies to p22, a hepatitis C virus (HCV) nucleocapsid protein, and to c100-3, a HCV nonstructural protein, in donors whose blood was transfused to patients who later developed post-transfusion non-A, non-B hepatitis. Of 13 such blood donors, three seroconverted and three seroreverted with the anti-c100-3 test. In contrast, 12 of the 13 blood donors showed the same results at transfusion and follow-up, and one donor showed seroconversion with the anti-p22 assay. The follow-up study shows that the anti-p22 antibody test provides consistent results and is far more suitable for screening blood than the anti-c100-3 test.