On the viral safety of plasma pools and plasma derivatives

In the industrialized world, a range of medicinal products are manufactured on a large scale from pools made of thousands of human blood and plasma donations. Policy makers as well as the general public are aware of the hazards of contamination following accumulated risks of individual donations. Today, the manufacturing process must therefore consider a complex sequence of risk reducing interventions, including screening tests and quarantine periods on pools and individual donations. We estimate the residual risk of hepatitis C infection following such sequences of events. This is the most common blood-borne infection in the western world, which affects an estimated 170 million people worldwide. We investigate the benefits and drawbacks of each intervention and study at several stages the dependence of the screening process on operational parameters that can be optimized, such as the number of donations from different donors in the pool and the length of the quarantine period. This leads to alternative risk reducing strategies that may be more (cost) effective or optimal under specific criteria. Copyright 2005 Royal Statistical Society.