Effect of donor and recipient CMV serostatus on survival after HSCT in 2 large cohorts. Donor serostatus did not affect survival among seropositive or seronegative HSCT recipients in the NMDP study (curve on the left). In contrast, donor CMV serostatus affected overall survival among recipients of unrelated allografts in the European Group for Blood and Marrow Transplantation (EBMT) study (curve on the right). Figures used with permission.^2,3