BACKGROUND: This study was designed to estimate the cost-effectiveness of expanding the human immunodeficiency virus (HIV)-testing protocol for donated blood beyond screening for HIV antibodies to further reduce the risk of HIV transmission through transfusion.

STUDY DESIGN AND METHODS: A Markov decision analysis model was developed to estimate the cost-effectiveness of HIV antibody testing (at a cost of $5/unit) and of adding to that protocol a second HIV test, either plasma p24 antigen detection or RNA polymerase chain reaction (PCR) (at costs of $5/unit and $8/unit, respectively). Test efficacy was projected from anticipated window-period reductions (6 days for p24 antigen, 11 days for RNA PCR), and donor seroconversion rates were derived from the Retrovirus Epidemiology Donor Study.

RESULTS: On the basis of current estimates of HIV prevalence rates in blood donors (1/10,000) and 16 million annual transfusions in the United States HIV antibody testing prevents 1568 cases of transfusion-acquired HIV infection each year at a cost of $3600 per quality-adjusted year of life saved. The addition of p24 antigen testing would prevent 8 more cases at a net additional cost of $60 million annually ($2.3 million/quality-adjusted life year); RNA PCR testing would prevent 16 more cases at a net additional cost of $96 million annually ($2.0 million/ quality-adjusted life year).

CONCLUSION: Although expanding the donor HIV screening protocol with p24 antigen or RNA PCR testing will prevent rare cases of transfusion-associated HIV, the cost-effectiveness of such an addition is predicted to be far below that of most medical interventions. Thus, HIV test protocol additions are unlikely to provide cost-effective improvements to blood safety in the United States.