Residual risk of transfusion-transmitted cytomegalovirus infection: incidence and pathogenesis

Cytomegalovirus (CMV) is a very common virus that infects most people during their lifetime without causing illness. CMV can be transmitted by blood transfusion. Some transfusion recipients such as premature infants with low birthweight, pregnant women and patients who receive transplants can become severely ill when infected. The process of filtering all blood donated to reduce the number of white blood cells eliminates almost all the risk of acquiring CMV from blood transfusion. However, a very low risk of "breakthrough" CMV infection remains. Approximately I% to 3% of high risk patients who have never been infected with CMV before are susceptible and appear to continue to acquire CMV from blood transfusion. The research proposed better defines this risk by studying how many susceptible patients who receive organ transplants became infected and ill with CMV acquired from transfusion. We will also determine the rate at which blood donors become infected with CMV over their lifetime and whether recently -infected blood donors are more likely to transmit CMV. We will specifically look at the liquid (plasma) part of the blood of subjects with recent infection to determine whether it contains virus that is not cleared in the filtration process. Other causes of "breakthrough" CMV infections, including the accuracy the screening tests used to determine whether a blood donor or transfusion recipient has previously been infected with CMV will be examined. These studies will provide information to assist Canadian Blood Services in developing policies to further reduce transfusion- transmitted CMV infection.

PREIKSAITIS, Jutta

University of Alberta

Intramural Research Grant Program

Alberta

$260,451