The Risk of Transfusion Transmitted Infections – Current Aspects*

Surveillance of infectious disease markers in the blood donor population is important to recognize trends in prevalence and incidence of relevant infections. These data are essential to calculate the risk of an undetected infectious donation entering the blood supply and to evaluate the potential benefit of new tests shortening the window period, e.g. the introduction of minipool or individual donation nucleic acid amplification technique (NAT). Prevalence and incidence of transfusion-relevant infections are low in the blood donor population in Germany. A careful selection of donors combined with consistent testing of all donations guarantee the very high safety standard of blood transfusions. However, from 1999 to 2003 prevalent HIV infections increased significantly among firsttime donors. Further studies are necessary to investigate the observed trend. The risk of a window period donation in the study period 2002/2003 was estimated to be 1 in 4.6 million for HIV, 1 in 4.2 million for HCV and 1 in 260,000 for HBV. Implementation of HCV NAT testing has markedly improved transfusion safety because of the clear shortening of the window period, whereas the calculated benefit of HIV-1 NAT or HBV NAT is not quite so pronounced.