In the United States, blood components are commonly used for patients in need of massive transfusion after blood loss. In combat situations, when severe traumatic injuries occur far from a hospital, fresh whole blood is a valuable transfusion therapy because components may not be available. The risk of infectious or immunological complications from fresh whole blood transfusions could be mitigated by a system that reduces pathogen loads and inactivates white blood cells (WBCs). Such a system is in development and utilizes riboflavin and ultraviolet light to provide pathogen reduction and WBC inactivation.

Study Design and Methods

The system has been tested with in vitro and in vivo animal studies to evaluate WBC inactivation and pathogen reduction, and with in vitro studies to assess the function of the treated blood products.


Elimination of viable WBCs with the system is equivalent to gamma-irradiation. Results have been reported for reduction of Babesia microti, Trypanosoma cruzi, HIV, and bacteria, and preliminary results for Babesia divergens are available. Treated whole blood, platelets, and plasma maintain coagulation function. Treated red blood cell components exhibit low hemolysis and high adenosine triphosphate levels at the end of storage.


Treatment with riboflavin and ultraviolet light is a promising alternative to gamma-irradiation. Effectiveness of the system against a variety of pathogens has been established, and further studies are planned. The in vitro studies of function indicate that treated whole blood, as well as components from treated whole blood, will provide acceptable hemostasis and perform well in the next phase of in vivo studies.