Pathogen‐reduced platelet concentrates in France: Impact on the risk of transfusion‐transmitted infections, 2017–2024

BACKGROUND AND OBJECTIVES: Pathogen reduction (PR) using amotosalen-UVA was implemented for 100% of platelet concentrates (PCs) in France in November 2017. No bacterial testing was in place earlier. The impact of PR on the risk of transfusion-transmitted infections (TTIs) from November 2017 to December 2022 (vs. January 2013 to October 2017) has been published previously. To further assess the impact of PR implementation, the evaluation period was expanded to December 2024. MATERIALS AND METHODS: PC-associated TTIs occurring in 2023 and 2024 were analysed and included in the assessment. RESULTS: Two cases of PC-associated transfusion-transmitted bacterial infections (TTBIs) were reported. The first involved Bacillus mobilis in a split pooled whole blood-derived PC. This Grade 2 TTBI was diagnosed following identification of the same pathogen in the second PC unit, quarantined for failed swirling test. The second involved Staphylococcus ureilyticus in an apheresis PC transfused to a patient who subsequently died. TTBI frequency decreased from 1/97,098 PC (n = 15 over 5 years, 2 deaths) to 1/787,662 PC (n = 3, over 7 years, 1 death) after PR implementation (p < 0.001). No human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), human T-cell lymphotropic virus (HTLV) or arboviruses TTI were reported from 2013 to 2024. No further cases of PC-associated hepatitis E virus (HEV) TTI were reported, concomitantly to HEV-nucleic acid testing implementation. A PC-associated parvovirus B19 TTI occurred in 2024. The use of PR PCs facilitated PC supply during arboviral outbreaks. CONCLUSION: The reduction in PC-related TTBIs following PR implementation is confirmed. However, the recent occurrence of two severe TTBI cases highlights a persistent risk. Prevention of PR-PC-associated TTIs by non-enveloped viruses requires specific screening.