Why 'safer than ever' may not be quite safe enough

Although the blood supply in developed countries is now very safe, residual microbial risks can still be identified. These are mainly due to bacteria. A wide range of sophisticated (and resource-consuming) interventions are in place which are generally successful in dealing with the risk from known viral agents. However, newly emergent viral risks can usually only be addressed after they have been shown to transmit and after tests have been developed. Parasitic and, even more significantly, bacterial risks (especially in platelet preparations which have to be stored at 22 degreesC) have often not been managed as effectively as the risk for the 'known' viruses such as HIV, HBV and HCV. Pathogen inactivation (PI) offers an approach to remove the vast majority of microbial risks. In the future, if the full inventory of transfusable components can be effectively pathogen-inactivated, PI could form an alternative basis for blood safety in terms of microbial risk, rather than just another incremental safety intervention.