Pathogen Reduction Technologies

Blood safety is of major importance in transfusion medicine. To decrease safety risks, a combination of donor education, screening, and testing for selected agents has been implemented. Pathogen reduction (PR) technology (PRT, also known as pathogen inactivation) is a proactive approach to reduce contaminating pathogens.

HIV in the blood supply resulted in many infected patients in the 1980’s. This spurred development of methods to better safeguard the blood supply, including implementation of enhanced donor screening criteria and sensitive tests based on nucleic acid detection or immunologic methods. These safety measures have drastically reduced risks of transfusion-transmitted infections. However, pathogen screening does not eliminate the risk completely, due to the window period where tests are negative but the unit may be infectious. Furthermore, emerging infectious agents such as chikungunya, West Nile, dengue, Ebola, and Zika viruses have increased through international travel, shipment of goods, and changing climatic conditions. Development of tests and deferral policies may take time. Thus, PR represents a potential proactive rather than reactive approach. Additionally, PR inactivates donor white blood cells (WBCs), thereby eliminating the need for irradiation to prevent TA-GVHD. Several PRT systems are in clinical practice ( Table 48.1 ).