Comprehensive analysis of parvovirus B19 infection in blood donors: epidemiological trend and implications for transfusion safety and management strategies in Italy.

Parvovirus B19 (B19V) presents a significant concern in the context of blood transfusion safety, given its potential for transmission through contaminated blood products, and the increased viral circulation recently reported across Europe. This study examines the recent epidemiological trends of B19V in Italy, where a notable increase in B19V-positive plasma units was observed during early 2024. While routine NAT testing for B19V in individual blood donations is not currently justified, the existing screening protocols for plasma intended for industrial fractionation are crucial to ensure the safety of plasma-derived medicinal products. However, this situation requires careful consideration of the optimal management of viremic donors and the implementation of targeted look back procedures to trace and monitor recipients of labile blood components. To address these issues, we propose an algorithm for managing both donors and recipients in cases of B19V positivity. These measures aim to balance recipient safety with minimising donor loss, while also addressing significant operational and ethical considerations within blood establishments.