Also with a restrictive transfusion policy, screening with second-generation anti-hepatitis C virus enzyme-linked immunosorbent assay would have reduced post-transfusion hepatitis C after open-heart surgery.

The incidence of post-transfusion hepatitis non-A, non-B (PTH-NANB) was prospectively assessed among open-heart surgery patients from the southeast region of Sweden before the introduction of antihepatitis C virus (HCV) blood donor screening. Blood samples for alanine aminotransferase analysis were drawn before and 2, 3, and 4 months after transfusion. Surgery was performed in four centres. Of 190 transfused and followed-up patients 2 (1.1%) contracted PTH-NANB, both operated on at the centre with significantly fewer transfusions than the other centres. One patient had antibodies to HCV detected by first-generation (C100-3) and later by second-generation anti-HCV enzyme-linked immunosorbent assay (ELISA-2) and by positive second-generation recombinant immunoblot assay (4-RIBA). The other patient, although negative by first-generation anti-HCV ELISA, was positive by second-generation ELISA and by 4-RIBA. Both patients were hepatitis C-viremic by polymerase chain reaction (PCR). All the six donors implicated in the two hepatitis cases were first-generation anti-HCV-negative, but two, one for each patient, were positive by second-generation anti-HCV ELISA. This finding was confirmed by positive 4-RIBA in only 1 donor, the other being 'indeterminate'. However, in both donors hepatitis C viremia was found by PCR. This study shows that the second-generation anti-HCV ELISA will further reduce the risk for PTH-NANB/C and draws attention to the problem of evaluation of confirmatory tests.