Transfusion transmitted hepatitis C and non-A, non-B, non-C.

The decline in the incidence of TAH from 1985-1990 was considerable and based on a variety of interventions that led to increasingly intensive scrutiny of potential donors. The decline in incidence observed since 1990, and particularly since 1992, has been truly extraordinary and based principally on the introduction of specific assays to detect carries of HCV. We are now at a time when the incidence of TAH is approaching zero and is almost certainly under 0.5% per transfusion episode. Such low rates have called into question the continued need for surrogate assays even though it is now clear that such assays played an important role in the prevention of hepatitis C prior to the introduction of HCV-specific assays. It is possible that anti-HBc testing may be abandoned as a surrogate, but retained as a specific marker for HBV infection. The retention of ALT testing may ultimately depend on whether there is another clinically significant human hepatitis agent (HFV). At present, there is only indirect and inconclusive evidence for such an additional agent and questions regarding its clinical relevance.