Antibodies to HTLV‐I p24 in sera of blood donors, elderly people and patients with hemopoietic diseases in France and in French West Indies

Human T‐cell lymphoma/leukemia virus type I (HTLV‐I) is a type‐C retrovirus originally isolated from patients with leukemia or lymphoma involving mature T lymphocytes. Epidemiological studies have shown that HTLV‐I infection occurs not only in leukemic but also in normal people in at least two areas of the world: the Caribbean basin and the South‐West of Japan. We report here the results of a large seroepidemiological study of HTLV‐I infection in normal French blood donors, elderly subjects living in institutions and patients with various malignant hemopathies, obtained by the classical HTLV‐I p24 radioimmunoassay. We were unable to demonstrate antibodies to HTLV‐I in 510 sera from French volunteer blood donors born and living in continental France or in sera from 262 blood donors born in other countries (mainly in Europe and North Africa) and living in contintental France at the time of collection. In contrast, among 131 sera from blood donors born in French overseas territories (French Guiana, French West Indies, and Reunion) but living at the time of collection in continental France, 2 (1.5%) were found to possess anti‐HTLV‐I antibodies. In a sample of 2,597 blood donors from Martinique, 39 (1.5%) were positive. A positive correlation with age was observed whereas no statistical relationship was found between HTLV‐I antibodies and sex, red cell blood groups or the place of residence in Martinique. On the other hand, a very high level of positive values was observed in Martinique among old people living in institutions, 14% of those aged over 60 years being positive. HTLV‐I‐associated hematological malignancies have not been observed in patients born and living in continental France whereas a large number exist in the French West Indies. In the same area, the presence of anti‐HTLV‐I antibodies in 12% of patients with myeloma, a typical B‐cell disease, merits attention.