Viral Infections

Blood components will be virally contaminated if a donor has viremia, which means the donor carries viruses in his/her bloodstream, at the time of collection. Over the last 20 years, the risk of viral infection via blood transfusion has been reduced significantly by integrating highly-sensitive virus screening tests into the blood processing procedure, to avoid transmission of viruses such as HIV, hepatitis, and the virus that causes adult T-cell leukaemia/lymphoma (ATL). Several lines of evidence suggest that HTLV-1 causes ATL. To develop and implement these tests, a virus needs to be identified as a blood supply risk. However, viruses may emerge, re-emerge or expand their reach due to increases in travel, immigration and climate change. Typically, there is a lag between the (re)emergence of a virus and the recognition that an additional safety intervention may be required.