School failure and deafness after "silent" congenital cytomegalovirus infection.

We found IgM antibody directed against cytomegalovirus in the umbilical-cord blood of 53 of 8644 newborns. Forty-four of the 53 had psychometric and pediatric evaluations at 3.5 to 7.0 years of age. The group's mean IQ was 102.5+/-22.4 (+/-S.D.), whereas in matched controls it was 111.7 (PC 0.025). Bilateral hearing loss was present in five of 40 children with antibody against cytomegalovirus and in one of 44 matched controls without antibody (P less than 0.1). Three of the antibody-positive children, however, had profound deafness, an abnormality that occurs once in approximately 1000 children. The predicted school failure rate, based on IQ, behavioral, neurologic and auditory test data, was 2.7 times that of matched socioeconomic controls and eight times that of randomly selected controls. We conclude that clinically inapparent congenital cytomegalovirus infection can adversely affect central-nervous-system development.