Hold everything! Holding policies for protecting plasma supplies

In spite of advances in testing technologies for detecting infections such as human immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatiti s C virus (HCV), occasionally blood or plasma is collected that is potentia lly infectious, but is not detected as such by existing screening tests. We consider the effect of a holding policy for further reducing the number of potentially infectious units that are released for fractionation. The poli cy dictates a holding period during which all donated units are stored. If a donor tests positive for the infection in question at a subsequent donati on, then all of that donor's units currently in storage are discarded. Othe rwise, donated units are released at the end of the holding period. In the case of a single disease, we determine optimal holding periods as well as p olicies that are as effective as the best screening tests currently availab le. (C) 1999 Elsevier Science Inc. All rights reserved.