Serological survey of antibodies to the adult T-cell leukemia virus-associated antigen (HTLV-A) in Taiwan.

A serological survey of antibodies to the adult T-cell leukemia virus-associated antigen (HTLV-A) conducted in Taiwan revealed II seropositive individuals among 2,565 serum donors tested, which included 1,187 hospital or free clinic patients, 1,065 blood donors and 313 aborigines. The overall prevalence rate was 0.43% and was 0.90% (9/995) for adults aged 40 years or over, which was similar to the rates observed in the non-endemic areas in Japan. No highly prevalent area was demonstrated. The II seropositive individuals identified were 8 hospital or clinic patients, 1 blood donor and 2 aborigines. Among 108 various leukemia/lymphoma patients also studied, 7 were positive. These 7 anti-HTLV-A-positive patients also had clinicopathologic features of adult T-cell leukemia/lymphoma (ATL). Among 21 relatives of 3 seropositive individuals in the epidemiologic study, 2 were positive; and among 25 relatives of 5 ATL patients, 6 were positive. Our data support the contention that horizontal familial transmission of human T-cell leukemia virus (HTLV-I) is an important route and HTLV-I infection can occur on a different genetic background. Furthermore, the antibody titer did not correlate with the manifestation or the state of the disease.