Acquisition of cytomegalovirus infection by premature neonates.

In order to evaluate the risk of premature infants acquiring cytomegalovirus (CMV) infection, a prospective study was made of infants of 32 weeks gestation or less admitted to a neonatal unit. Infants were assessed at birth to exclude congenital CMV infection and followed to the age of 1 month post-term. A total of 16/131 (12.2%) infants acquired CMV infection; 6 of CMV antibody-negative and 10 of CMV antibody-positive mothers. Six of 65 (9.23%) infants of CMV antibody-negative mothers who had been transfused with blood acquired CMV infection compared with 0 of 18 infants of CMV antibody-negative mothers, and who had not been transfused with blood. Acquired CMV infection was also more common in infants of CMV antibody-positive mothers and who had been transfused with blood, i.e. 9 of 34 (26.47%) compared with 1 of 14 (7.14%). The relative risk was 3.7 (95% confidence interval 1.53-5.87). This study suggests that all premature infants requiring blood transfusion should be transfused with CMV antibody-negative blood regardless of the CMV immune status of their mothers.