FAMILIAL TRANSMISSION OF HUMAN T-LYMPHOTROPIC VIRUS TYPE-1 (HTLV-1) IN PATIENTS WITH ADULT T-CELL LEUKEMIA LYMPHOMA OR HTLV-1-ASSOCIATED MYELOPATHY/

The seroprevalence of human T-lymphotropic virus type 1 (HTLV-1) in Ta iwan is 0.48%. In this study, we investigated the patterns of intrafam ilial transmission of HTLV-1 in Taiwanese patients with adult T-cell l eukemia/lymphoma (ATL/L) or tropical spastic paraparesis/HTLV-1-associ ated myelopathy (TSP/HAM). Fifteen index patients (9 men, 6 women, age d 31-71 yr), 13 with ATL/L, and two with TSP/HAM, and 98 relatives wer e included. Of the 98 relatives, 23 were seropositive for HTLV-1. Spou ses of 11 patients were studied. Seven of eight wives of male patients but none of the three husbands of female patients were HTLV-1 carrier s. Mother-to-child transmission was found in seven of 13 families and in 15 of 75 children tested. The correlation of breast-feeding with se ropositivity in two families with seropositive mothers indicates its i mportant role in vertical transmission of HTLV-1. Our findings suggest that husband-to-wife and mother-to-child transmission are the main fo rms of intrafamilial transmission of HTLV-1 in Taiwan, a nonendemic ar ea. Screening for HTLV-1 in family members of patients with ATL/L or T SP/HAM, and seropositive blood donors, may be warranted. Seropositive individuals should be educated to prevent the spread of the virus thro ugh sexual contact and breast feeding.