Low prevalence in the UK of HTLV-I and HTLV-II infection in subjects with AIDS, with extended lymphadenopathy, and at risk of AIDS.

Antibodies reacting selectively with human T-cell leukaemia virus type I (HTLV-I) were detected in approximately 5% patients with extended lymphadenopathy syndrome (ELAS) and in less than 1% of unselected homosexual patients and drug abusers. None of 22 patients with acquired immunodeficiency syndrome (AIDS) had HTLV-I antibodies and neither did 85 haemophiliacs and 940 blood donors. 3 out of 113 drug addicts had high titres of antibodies to human T-cell leukaemia virus type II (HTLV-II). A T-cell line was derived from 1 of the seropositive ELAS patients. This line was found to be infected with, and releasing, HTLV-I. Infection by HTLV-I and HTLV-II retroviruses thus occurs more frequently in ELAS patients and drug addicts than in the UK population as a whole, but the low prevalence of these infections in ELAS and AIDS patients indicates that these two strains of lymphotropic retroviruses have no aetiological role in ELAS and AIDS.