Perinatal viral infections.

Among the TORCH agents, the occurrence of rubella and human T-lymphotropic virus type 1 (HTLV-1) in Japan were studied. Rubella epidemics occurred throughout Japan from 1964 to 1969 and from 1975 to 1979. Low prevalences of CRS were observed in northeastern Japan, and high prevalences in southwestern Japan, with the highest in Okinawa. These conditions could be explained by the lower rate of rubella H1 antibody in the female population of southwestern Japan. Time of maternal rubella was in the gestational age interval from 26 to 57 days for cataract, from 25 to 62 days for heart disease and from 16 to 131 days for deafness. HTLV-1 is the causative agent of adult T-cell leukemia. Main route of transmission of this virus is mother-to-child transmission, through breast milk. Among the 311 mother-child pairs in Okinawa, 65 mothers (20.9%) and 10 children (3.2%) were seropositive for HTLV-1. Ten (15.4%) of the 65 seropositive mothers had seropositive children. These children had acquired their HTLV-1 antibodies by the age of 3 years. A significant difference existed between the prevalence rate of HTLV-1 antibodies in mothers and children.