Absence of human T-lymphotropic virus types I and II infection in an Ontario hemophilia population.

Two hundred ninety-three serum samples from Ontario hemophiliacs and 200 samples from human immunodeficiency virus-positive blood donors were screened for the presence of antibodies to human T-lymphotropic virus type I (HTLV-I) by enzyme-linked immunosorbent assay, radioimmunoassay, and Western blot techniques. None of the serum samples provided unequivocal positive results, but several samples gave inconclusive results. Of the hemophiliacs with inconclusive serologic results from whom peripheral blood lymphocyte DNA could be obtained, all were negative for HTLV-I and HTLV type II (HTLV-II) sequences as determined by polymerase chain reaction (PCR). PCR was also performed on a lymph node biopsy sample taken from a hemophiliac who developed a rare T-cell lymphoma; the sample was negative for HTLV-I and -II sequences. These results indicate that Ontario hemophiliacs have not been exposed to HTLV-I or HTLV-II.