Development of antibodies against cytomegalovirus, varicella-zoster virus and herpes simplex virus in Finland during the first eight years of life: a prospective study.

To clarify when antibodies against cytomegalovirus (CMV), varicella-zoster virus (VZV) and herpes simplex virus (HSV) develop among young children, 1206 serum samples collected prospectively from 199 children born in 1989 and 1990 were studied. The samples were drawn at the ages of 7 and 13 months, then yearly until the age of 5 y and then at 7 and 8 y. In each age group at least 106 samples were collected. Immunoglobulin G class antibodies to the 3 viruses were measured using an enzyme immunoassay. At the age of 7 months 27% of the children had CMV antibodies, whereas only 3% had antibodies against VZV and 2% against HSV. The prevalence of seropositivity for CMV increased slowly to 41% by the age of 8 y. Seroconversions to VZV antibody positivity occurred frequently after 2 y of age, so that by 8 y 83% of children had VZV antibodies. The proportion of children with HSV antibodies remained low throughout the study, as only 17% of children had HSV antibodies at the age of 8 y. The data show that HSV infection is becoming acquired later in life and the proportion of uninfected children is increasing. The proportion of CMV infections during the perinatal period and early infancy remains high, in one-third of the children, and most children also have VZV infection during the early years of life.