A transfusion–transmitted infection (TTI) or transfusion–associated infection is a pathogen which is transmissible through donated blood and can give rise to infection in the recipient by way of transfusion. The term is usually limited to known pathogens, but also sometimes includes agents such as simian foamy virus which are not known to cause disease.
Following a number of highly publicized incidents throughout the 1970s-1980s, preventing disease transmission through blood donation is addressed through a series of safeguards. Blood safety measures that limit this risk of disease transmission through blood donation are considered essential in upholding public trust in blood donation, and to avoid harm to blood recipients who are frequently vulnerable to severe disease. The World Health Organization recommends screening potential blood donors for signs and symptoms of disease and for activities that might put them at risk for infection, including mandatory testing of donated blood for relevant pathogens prior to transmission, sometimes with several different methodologies. Additional safeguards, such as leukoreduction and pathogen inactivation can be applied, and are frequently mandatory. If a local supply is not safe, select blood may be imported from other areas.
