Evaluation of Pathogen Reduction Systems to Inactivate Dengue and Chikungunya Viruses in Apheresis Platelets Suspended in Plasma

The risk of blood-borne transmission of infectious diseases has led to an increasing awareness of the need for a safe and effective pathogen reduction technology. This study evaluated the efficacy of 2 pathogen reduction systems to inactivate dengue virus (DENV-2) and chikungunya virus (CHIKV) spiked into apheresis platelets (APLT) concentrates. Double-dose APLT collections (n = 3) were split evenly into two units and spiked with 10 infectious units of DENV-2 or CHIKV. APLTs samples were assayed for viral infectivity before and after Amotosalen photochemical treatment (PCT) or Riboflavin pathogen reduction treatment (PRT). Viral infectivity was determined by plaque assays. Platelet (PLT) count, pH and residual S-59 were measured during the storage of 5 days. Amotosalen PCT showed robust efficacy and complete inactivation of both viruses in APLTs, with up to 3.01 and 3.75 log reductions of DENV-2 and CHIKV respectively. At similar initial concentrations, Riboflavin PRT showed complete inactivation of CHIKV with up to 3.73 log reduction, much higher efficacy than against DENV-2 where a log reduction of up to 1.58 was observed. All post-treated APLTs maintained acceptable PLT yields and quality parameters. This parallel study of 2 pathogen reduction systems demonstrates their efficacy in inactivating or reducing DENV and CHIKV in APLTs and reaffirms the usefulness of pathogen inactivation systems to ensure the safety in PLTs transfusion.