Evaluating plasma holds in the presence of multiple infections.

Abstract

To protect plasma supplies, donors are screened for infectious diseases. As an added measure of protection, donations are identified and stored for a period of time to allow future discard in the event that an identified donor subsequently tests positive for some screened disease. Previous models for evaluating such plasma holds have only addressed the case of a single infectious disease. This paper extends the analysis to the case of multiple infections. Given knowledge of the marginal incidence rates for those infections checked, upper and lower bounds for important quantities such as the probability of interdicting an infectious but undetected donation, the expected number of infections interdicted per donation, and the net economic benefits of the holding policy are developed. Several examples are developed, illustrating how the models can be used to evaluate the consequences of a plasma hold.