Defining "adequate" pathogen reduction performance for transfused blood components.

Pathogen reduction of labile blood products offers the opportunity to introduce to the blood banking community the same mechanism of protection that is employed for fractionated or pooled plasma products today--blood components that have been treated with methods to inactivate or reduce the infectivity of a variety of organisms that may contaminate donated blood and thus potentially transmit infection via transfusion. Due to the mechanisms of action, the methods employed in the plasma fractionation environment are not directly applicable to labile blood products. This article examines whether the same criteria of performance required for plasma derivatives (i.e., 6 log/mL reduction by multiple orthogonal methods) should be applied to the treatment of labile components and if not what criteria for performance might be sufficient. In conducting this analysis, we have considered what has been learned in the past several decades regarding the dynamics and infectivity of various pathogens and disease transmission by blood products, the introduction and progressive enhancement of testing methods based on serology and nucleic acid testing, and the performance characteristics for pathogen reduction technologies that are available today.