Seroprevalence of human T-lymphotropic virus in blacks from a selected central Brooklyn population

Human T-cell leukemia virus type I (HTLV-I) has been causally linked to adult T-cell leukemia/lymphoma and tropical spastic paraparesis/HTLV-I-associated myelopathy. Few seroprevalence studies have been carried out in the United States. Because of the number of reports of adult T-cell leukemia/lymphoma and tropical spastic paraparesis/HTLV-I-associated myelopathy in blacks from central Brooklyn, New York, we decided to initiate a seroprevalence study in this community. Intravenous drug users and male homosexuals were excluded. A total of 480 individuals from medical clinics and health fairs were surveyed via questionnaire, and their sera were assayed for HTLV-I/II antibody by two laboratories. An overall seroprevalence rate was 21/480 (4.4%). This is almost 200 times greater than a study of a national sample of U.S. blood donors. Rates were similar for individuals originating from the United States and the Caribbean. Nine of the 21 seropositive individuals returned for further testing. Polymerase chain reaction assays revealed that 8 were positive for HTLV-I and 1 for HTLV-II. Although this group may not be representative of the "normal" black population of central Brooklyn, the high seroprevalence rate necessitates that the incidence of HTLV-I-associated illnesses be determined in this community.