In the past, transfusion-transmitted virus (TTV) infections were not uncommon. In recent years with advanced technologies and improved donor screening, the risk of viral transfusion transmission has been markedly reduced. Hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV) have all shown marked reduction in transmission rates. However, the newer technologies, including nucleic acid technology (NAT) testing, have affected the residual rates differently for these virally transmitted diseases. Zero risk, which has been the goal, has yet to be achieved. False negatives still persist, and transmissions of these viruses still occur, although rarely. It is known that HBV serological testing misses some infected units; likewise, HBV NAT-negative units have also been known to transmit the virus. Similarly, HIV minipool NAT-negative units have transmitted HIV, as recently as 2007; likely, these transmissions would have been prevented with single-unit NAT testing. Newer technologies, such as pathogen inactivation (PI), will (ideally) eliminate these falsely test negative components, regardless of the original testing method used for detecting the viruses.