Prevention of transfusion-transmitted cytomegalovirus infection

Cytomegalovirus (CMV) is a double-stranded DNA virus which can be transmitted by blood transfusion. Its seroprevalence in adults ranges from 40% to 100% depending on geographical and socioeconomic conditions. Seropositive individuals have latent CMV infection with viral DNA present in peripheral blood leucocytes. CMV can be associated with considerable morbidity and mortality in susceptible individuals, e.g. CMV-seronegative bone marrow allograft patients. Evidence, from a number of reports, suggests that provision of leucodepleted blood components may be as effective as the use of components from CMV-seronegative donors in preventing CMV infection and disease. This is relevant in the UK because Blood Transfusion Services are implementing universal leucodepletion of cellular blood components to minimize the theoretical risk of transmission of new variant Creutzfeldt-Jakob disease. This review examines data on the biology of CMV, discusses options for testing and summarizes the impact of CMV-seronegative and leucodepleted blood components on transfusion-transmitted CMV.