The spread of TT-CMV in LBWIs can be curtailed by transfusing blood products that are CMV negative as well as to filter the white cells in blood that carry the virus (leukoreduction). The purpose of this study is to see if the use of these two strategies can lower the spread of CMV through a transfusion. How "safe" the blood actually is through leukoreduction is not known and CMV still occurs in LBWIs. It is not clear whether this approach is optimal or whether additional safety steps are needed to completely prevent TT-CMV. Specific actions that could tell us when virus has reached the blood product or breast milk is to test each of these to determine if virus slipped "unnoticed" and/or when the product was not thoroughly filtered.