Risk management in blood transfusion services.

Risk is usually simplistically defined as the probability of an adverse outcome, under-recognising the importance of perception. The intuitive centre of the risk structure is 1 in a million (10(-6)), the background risk of death in developed countries. In Australia, current risks of transmission of HIV and HCV by blood transfusion are about 10(-6), the risk is higher for HBV and lower for HTLV1, but the risk of death from the infections is much less, particularly for HTLV1. When blood service professionals take risk related actions, their judgement must be tempered by contemporary political and social realities and the public's real and disproportionate horror of catastrophe.