Photochemical inactivation of chikungunya virus in plasma and platelets using the Mirasol pathogen reduction technology system

BACKGROUND: Chikungunya virus (CHIKV) is a reemerging mosquito-borne virus that has been responsible for a number of large-scale epidemics as well as imported cases covering a wide geographical range. As a blood-borne virus capable of mounting a high-titer viremia in infected humans, CHIKV was included on a list of risk agents for transfusion and organ transplant by the AABB Transfusion-Transmitted Diseases Committee. Therefore, we evaluated the ability of the Mirasol pathogen reduction technology (PRT) system (CaridianBCT Biotechnologies) to inactivate live virus in contaminated plasma and platelet (PLT) samples. STUDY DESIGN AND METHODS: Plasma, PLTs, and phosphate-buffered saline controls were spiked with CHIKV and treated with riboflavin and varying doses of ultraviolet (UV) light using the Mirasol PRT system. Samples were tested before and after treatment for cytotoxicity, interference, and virus titer by titration and quantitative real-time reverse transcriptionpolymerase chain reaction. RESULTS: A significant reduction in CHIKV titer of greater than 99% was recorded after treatment of plasma or PLTs with the Mirasol PRT system, and the titer reduction was directly proportional to the UV dose delivered to the samples. No cytotoxicity of interference was observed in any sample at any treatment dose. CONCLUSION: These data indicate that the Mirasol PRT system efficiently inactivated live CHIKV in plasma and PLTs and could therefore potentially be used to prevent CHIKV transmission through the blood supply.