THE RISK OF TRANSMITTING INFECTIONS BY BLOOD COMPONENTS

Objective: Assessment of the present risk of blood-borne infection ass ociated with homologous blood transfusion in Central Europe with parti cular emphasis on HIV and HCV infections. Data Sources: The relevant l iterature in the-English and German language and the authors' data. St udy Selection: No special study has been carried out for the present p aper. Results: The recognition of the risk for transmitting HIV by tra nsfusion has led to a bundle of measures which have improved the safet y of blood supply in Germany. A stricter donor selection as well as sc reening for HIV 1 and HIV 2 have reduced the risk to transmit HIV to t he order of 1 per 1 million units transfused. The transmission of hepa titis B is estimated to be in the order of 1:50,000. The anti-HCV test ing, introduced in 1990, has markedly reduced the transmission of HCV to less than 1: 5,000 per unit as judged from our own data. A further reduction is expected by an improved HCV screening in the near future. Fatal disease from bacterial contamination is rare, with an estimated risk of one in a million units. Syphilis transmitted by transfusion i s virtually not occurring anymore. However, increased efforts should c ontinue to enhance the safety of blood, bearing in mind that a zero ri sk is not achievable for effective therapies. The estimation of risks is a dynamic, time-dependent value which has to be estimated for a geo graphically defined population for a given time period. Conclusions: T he risk of transfusion-associated infection has been markedly reduced in recent years. Albeit there is a small but definitive risk, which is often over-estimated. The risks have to be defined to estimate the ri sk/benefit ratio of the homologous as well as the autologous transfusi on for the individual patient.