Viral risks of blood transfusion

Hepati becaus o r infu T h e ci and in mendc carryii screen effecti (PTH1 elimin Bef the a factor; P T H t Virusc recipii sion p H B . ] the lik I n 1 been factor drugs additi markc giving Franc antige hepat contri PTHI Thi serun the a antibi antibi blooc HBs/ poter A n vales f rom natei the v Drug t o re estab wort! ing F value scree fican Summary, Viral complications of modern blood transfusion a re negligible, but transfusion can never b e called totally safe. T h e most important risks a re transmission of hepatitis and human immunodeficiency ( H I V ) viruses. Systematic screening of blood donors for HBsAg greatly reduced t he incidence of post-transfusion hepatitis B , bu t virus transmission is still possible in t h e convalescence period when H B s A g test has become negative. T o avoid this possibility, some countries have started additional screening f o r anti-HBc. T h e decision depends o n t he prevalence of hepatitis B , a n d n o universal recommendation can b e given. T h e great majority of non-A, non-B post-transfusion hepatitis cases seem t o b e caused b y hepatitis C virus (HCV) . T h e second generation tests f o r ant i -HCV a re very useful fo r screening blood donors, and surrogate testing (e .g . A L T and anti-HBc) is not needed anymore. Careful donor selection and other preventive strategies including systematic laboratory testing f o r anti-HI V have greatly reduced t he risk of H I V transmission, but in t h e seronegative phase of t he disease transmission of infection is still possible in donated b lood . Antigen screening in donors does not solve this problem. Cellular products may transmit H T L V and C M V . I n the latter case, depletion of blood products of leukocytes is as good a strategy as using seronegative donors . T h e prevention of transmission of all viruses includes, in addition t o donor selection and laboratory screening, viral inactivation of products. This has been achieved with most plasma derivatives, and research is active with cellular products. Different preventive strategies should b e used simultaneously t o minimize t he risk a s much as possible.