Last Line to Secure Transfusion Safety: Pathogen Inactivation/Reduction Methods in Blood Products-Current Approaches and Perspectives
The residual risk of transfusion transmitted infection (TTI) had been decreased greatly since the donor screening methods, especially the nucleic acid testing (NAT), were introduced. NAT can shorten the period between infection and detection (window period) to several days after infection [1]. However, transfusion safety still faces challenges due to limitations of test sensitivity and more importantly the unexpected appearance of new pathogens. The newly discovered or re-emerging viruses such as West Nile virus, human parvovirus B19 and latest reported severe fever with thrombocytopenia syndrome bunya virus [2] in the donor blood endangered blood safety. Pathogen inactivation/ reduction (PI/PR) strategies provide last line of defence against various pathogens to secure transfusion safety. PI/PR refers to any technology that inactivates or reduces all types of blood borne pathogens. Different methods were designed for different blood products such as plasma, platelets and red blood cells (RBCs). An ideal PI/PR is expected to inactivate all blood borne pathogens without damaging the quality of blood or blood products. Some common PI/PR methods include treatment with solvent/detergent (S/D), Methylene blue, Psoralens, Riboflavin. Some new technologies for PI/PR are under development