Search

Background and objectives: Chikungunya virus (CHIKV) infections have been reported in all continents, and the potential risk for CHIKV transfusion‐transmitted infections (TTIs) was demonstrated by the detection of CHIKV RNA‐positive donations in several countries. TTIs can be reduced by pathogen inactivation (PI) of blood products. In this study, we evaluated the efficacy of amustaline and glutathione (S‐303/GSH) to inactivate CHIKV in red‐blood‐cell concentrates (RBCs). Material and Methods: Red‐blood‐cells were spiked with high level of CHIKV. Infectious titres and RNA loads were measured before and after PI treatment. Residual CHIKV infectivity was also assessed after five successive cell culture passages. Results: The mean CHIKV titres in RBCs before inactivation was 5·81 ± 0·18 log10 50% tissue culture infectious dose (TCID50)/mL, and the mean viral RNA load was 10·49 ± 0·15 log10 genome equivalent (GEq)/mL. No CHIKV TCID was detected after S‐303 treatment nor was replicative CHIKV particles and viral RNA present after five cell culture passages of samples obtained immediately after S‐303 treatment. Conclusion: Chikungunya virus was previously shown to be inactivated by the PI technology using amotosalen and ultraviolet A light for the treatment of plasma and platelets. This new study demonstrates that S‐303/GSH can inactivate high titres of CHIKV in RBCs. [ABSTRACT FROM AUTHOR]

Background: With an increasing number of recognized transfusion-transmitted (TT) babesiosis cases, Babesia microti is the most frequently TT parasite in the United States. We evaluated the inactivation of B. microti in red blood cells (RBCs) prepared in Optisol (AS-5) using amustaline and glutathione (GSH) and in platelet components (PCs) in 100% plasma using amotosalen and low-energy ultraviolet A (UVA) light.Study Design and Methods: Individual RBCs and apheresis PCs were spiked with B. microti-infected hamster RBCs (iRBCs) to a final concentration of 106 iRBCs/mL and treated with the respective inactivation systems according to the manufacturer's instruction. Samples were collected before (control) and after (test) each treatment. Dilutions of the control samples to 10-6 were inoculated into hamsters, while the test samples were inoculated neat or at 10-1 dilution. At 3 and 5 weeks postinoculation, hamsters were evaluated for B. microti infection by microscopic observation of blood smears and 50% infectivity titers (ID50 ) were determined. Log reduction was calculated as control log ID50 minus test log ID50 .Results: Parasitemia was detected in hamsters injected with as low as 100,000-fold diluted control samples, while no parasites were detectable in the blood smears of any hamsters receiving neat test samples. Mean log reduction was more than 5 log/mL by amustaline/GSH for RBCs and more than 4.5 log/mL by amotosalen/UVA for PCs.Conclusion: B. microti was inactivated to the limit of detection in RBCs and PCs after the respective inactivation treatment. Complete inactivation of B. microti was achieved in this animal infectivity model, and pathogen reduction treatment inhibited transmission of infection. [ABSTRACT FROM AUTHOR]