ABSTRACT
Blood transfusion has become increasingly safe worldwide since the introduction of screening tests for transfusion-transmitted infectious diseases (TTD) (1) and an extensive series of other measures to minimize the risk to recipients of blood, blood components, and derivatives. Two events triggered dramatic improvements in blood safety in the United States in the 1970s: the conversion to all-volunteer, unpaid donors of blood for transfusion (2) and the widespread introduction of tests for hepatitis B surface antigen that could be applied at the level of mass screening (3). Cases of posttransfusion hepatitis dropped from about 25% of recipients to about 5% of recipients.
