Recycled incomplete identification procedures for blood screening

The operation of blood bank systems is characterized by two crucial factors: testing procedures and perishability. We propose a new testing procedure that we term Recycled Incomplete Identification Procedure (RIIP). In RIIP, groups of pooled blood units which are found contaminated in a so-called ELISA test are divided into smaller subgroups and again group-tested by ELISA, and so forth, until finally a so-called PCR test is conducted for those subgroups which are found clean. We analyze and optimize the performance of RIIP, maximizing the profit associated with the procedure. Our numerical results suggest that it may indeed be profitable to do several cycles at ELISA.