The primary source of postnatal infection with cytomagelovirus (CMV, a common virus usually without symptoms) in very-low-birth-weight (VLBW) infants appeared to be maternal breast milk because no infections were linked to transfusions of CMV-seronegative and leukoreduced blood products.
Transfusion-transmitted CMV (TT-CMV) and breast milk-transmitted (BM-CMV) infection can cause serious illness and death in VLBW babies with immature immune systems. Using CMV-seronegative and/or leukoreduced blood components is a common strategy to prevent TT- CMV. The authors examined the risk of CMV infection from transfusion of CMV-seronegative and leukoreduced blood components, as well as CMV transmission from maternal breast milk.
The authors conducted their study in three neonatal intensive care units in Atlanta. The study enrolled mothers, who were tested to determine their CMV status, along with 539 VLBW infants (birth weight less than or equal to 1,500 grams) who had not received a transfusion.
The seroprevalence of CMV was 76.2 percent (n=352) among the 462 mothers enrolled in the study. Among the 539 VLBW infants, the incidence of CMV infection at 12 weeks was 6.9 percent; 5 of 29 infants (17.2 percent) with postnatal CMV infection developed symptomatic disease or died. A total of 2,061 transfusions were given among 57.5 percent (n=310) of the infants. None of the CMV infections were linked to transfusions. Of the 28 postnatal infections, 27 occurred among infants fed CMV-positive breast milk (12-week incidence, 15.3 percent).
"The frequency of CMV infection in our cohort raises significant concern regarding the potential burden of CMV infection among VLBW infants and potential sequelae. This concern necessitates large, long-term follow-up studies of neurodevelopmental outcomes in infants with postnatal CMV infection."