Detection of HTLV-I sequence in infants born to HTLV-I carrier mothers by polymerase chain reaction

We applied the polymerase chain reaction (PCR) method to detect gag and pX sequences of human T-lymphotropic virus type I (HTLV-I) provirus in peripheral blood lymphocytes. The new method was used to examine babies delivered hy HTLV-I carrier women for HTLV-I vertical transmission. It was found that intrauterine/transvaginal infection with HTLV-I can occur, though rarely, and some babies carry HTLV-1 provirus despite their negative response to HTLV-I antibody. Of note is that some of the babies found negative by the conventional antigen detection method may be positive when tested by the PCR method. It was also confirmed with the PCR method that vertical transmission of HTLV-I can occur at high incidence rates and these infection rates can be reduced to about 1/7 by replacing breast feeding with bottle feeding and frozen mother's milk feeding These results suggest that PCR is more sensitive than the conventional antigen detection method and is useful in early detection of HTLV-I infection in neonates born to HTLV-I carriers.