[Significance and limit of the tests for prevention of transfusion-associated infectious diseases]

To prevent virus infectious associated with transfusion the excellent screening tests should be implemented. The blood screening tests should comply with five "S" requirements, in other words it should be sensitive, specific, simple, speedy and safe. In the very first stage of the virus infection, a term called "window period", during which infectious agents, are undetectable by current assays. So the possibility of viral transmission is still remain. Therefore, after due consideration of the benefits and the risks of blood transfusion and only in the case of its efficacy is expected enough, minimal volume of blood should be transfused. Furthermore, the transfusion should be into practice after thorough informed consent.