Emerging viruses in blood transfusion

Background and Objectives: The development of new technologies leads to the discovery of new viruses. For each of these new infectious agents relevanc e to transfusion needs to be assessed. Materials and Methods: The questions to be answered are transmissibility by transfusion, pathogenicity, prevale nce in blood donors, persistence and the availability of screening assays. Results: Since 1995, four new viruses have been identified and for three of them extensive studies have been carried out. GBV-C/HGV and TTV were both initially thought to be related to post-transfusion hepatitis but neither w ere proven to be in any way related to hepatitis and are still in search of a disease. HHV-8 is a major factor in the pathogenesis of Kaposi's sarcoma and other tumours related to immunodeficiency. HHV-8 transmission by organ transplantation but not by transfusion has been demonstrated. SEN-V has be en claimed as a potential cause of non-A-E hepatitis but no data has been p ublished. Conclusion: To date, none of the emerging viruses have been prove n relevant to transfusion.