Screening for anti-human T-lymphotropic virus antibody in blood donors and polytransfused patients in Apulia (Italy).

A stringent procedure for the diagnosis of human T-lymphotropic virus (HTLV) infection was applied to 1,732 volunteer blood donors, 401 patients with various hematological disorders and 78 individuals at high risk for HIV infection. It consisted of a viral lysate-based screening assay (Abbott Laboratories, North Chicago, Ill., USA), and two confirmatory assays (Western blot and radioimmunoprecipitation assay). A confirmed positive sample had to react with at least two different HTLV gene products. Evidence of HTLV infection was not found in either blood donors or patients with hematological disorders. In fact, HTLV infection was only observed in 10 intravenous drug abusers or their sexual partners. Contrary to previous reports that claimed HTLV seroprevalences of between 0.3 and 8% in blood donors from Apulia (Italy), our data suggest that infection with this virus is principally restricted to intravenous drug abusers.