Estimation of the Infectious Risks of Blood Transfusion

Despite the success of efforts made to prevent the transmission of infections by blood transfusion, the risk of infectious donations entering the blood supply and transmitting infection to the recipients of blood components and blood products remains a concern. Following the implementation of donor selection and donation testing strategies to exclude HBV, HIV, and HCV infectious donations from the blood supply, direct observation of transmission of these viruses by blood transfusion has become rare and indirect estimation of the probable frequency of infectious donations entering the blood supply has become more common. Published estimates for different blood services and different periods of time have varied in their methods and scope. The limitations of the estimation process should be considered when using estimates of the risk of infectious donations entering the blood supply to address questions about blood safety.