Cytomegalovirus infection in day care centers in Rome, Italy: viral excretion in children and occupational risk among workers.

From nine day care centers in Rome, Italy, 253 children of middle to low socioeconomic classes were examined for cytomegalovirus (CMV) excretion in saliva. The overall excretion rate was 13%, with no marked differences between centers. Socioeconomic level, age of enrollment, chronological age, length of attendance, and number of siblings did not have any discernible influence on viral shedding. The most notable result is that during the second year of age, 100% of the excretors had been breast fed, but only 60% in the third year, indicating that maternal transmission is the most likely source of children's infection early in life. Serologic survey of 82 female workers in day care centers, 82 matched housewives, and 229 female students aged 14 to 18 years who were in training to care for children showed that at 14 years of age the CMV seropositivity rate is 85, which suggests that primary infection during childbearing age is an uncommon event in Rome.