Mother-to-Child Transmission of Human T-Lymphotropic Virus Type II (HTLV-II)

Human T-lymphotropic virus type II (HTLV-II) is transmitted primarily by sharing contaminated needles and by sexual contact [1, 2]. Unlike for type I, vertical transmission of HTLV-II has not been documented, although breast-feeding has been suggested as a possible risk factor for HTLV-II transmission [3, 4]. Recent serologic analyses of prostitutes and Mayan Indians in Mexico identified women with HTLV-II infection [5]. We studied family members of four of these women who were positive for HTLV-II to identify the mode of transmission of HTLV-II to close family contacts. Although we could not document sexual transmission in the sexual partners of these women who were positive for HTLV-II, we report the first case of mother-to-child transmission of HTLV-II, which occurred in an 8-year-old child who was breast-fed from birth to 4 years.