High prevalence of HTLV-I infection among the family members of a patient with adult T-cell leukemia/lymphoma from northeastern Japan.

Human T-cell lymphotropic virus type I (HTLV-I) is transmitted through infected lymphocytes mostly by breast feeding. In the present study, high prevalence of HTLV-I infection was disclosed in the family members of a patient with adult T-cell leukemia/lymphoma (ATL), all of whom were residents of Iwate, northeastern Japan. Long-term follow-up is necessary for people with HTLV-I infection because of the risk of developing ATL after a certain period of latency. New inventive treatments for the acute and lymphomatous types of ATL are needed.