Metagenomics for Potential Emerging Infectious Pathogens Identification in Blood Donors with a Molecular Epidemiology Investigation of Human Parvovirus B19: A Multi-center Study in China

Background: Emerging infectious pathogens in blood donors may be transmitted through blood components or plasma derivatives transfusion. Currently, Chinese blood centers only routinely screen HBV, HCV, HIV, and Syphilis for donors, which would lead to some emerging infectious pathogens transmitted via transfusion.Metagenomic next-generation sequencing (mNGS) with bioinformatics analysis was employed in this study to investigate the microbial components with revealing theemerging infectious pathogens in blood donations from Chinese multi blood centers to enhance the blood safety. Results: A total 562 GB clean data was obtained in donation samples from 7 Chinese regions. The principal pathogens identified were Serratia sp. (5.0176%), Pseudomonas sp. (0.6637%), and Burkholderia sp. (0.5544%). Several transfusion transmitted pathogens including human parvovirus B19, Leishmania sp. , T oxoplasma gondii , etc. were identified as potential threats for Chinese blood safety. Subsequently, 9 (0.08%) specimens were found positive for B19V DNA with quantitative DNA levels ranged from 5.58% × 10 2 to 7.24 × 10 4 IU/ml. Phylogenic analyses showed B19-1A subtype as the prevalent genotypes. Conclusions: Emerging infectious pathogens including human parvovirus B19, Leishmania sp. , Toxoplasma gondii , etc., may pose transfusion risks in China. Therefore we strongly advise that mNGS surveillance should be wildly and continually implemented in blood centers. In addition, blood safety measures in China should take B19V risk into consideration in some endemic regions in China.