The prevalence of antibodies to human T-lymphotropic virus III (HTLV-III) was determined in a total of 140 hemophiliacs and 36 polytransfused patients from three medical centers by an enzyme linked immunosorbent assay (ELISA) and confirmatory tests. 58 hemophiliacs (41.4%) were seropositive. In all instances where the origin of the coagulation factors given to these patients could be determined, blood products came from the United States. In addition, 2 of 36 polytransfused patients, mostly with acute leukemias, who were transfused with blood products from local donors were positive for HTLV-III antibodies. No HTLV-III antibodies were detected in 237 blood donors selected in part from the donor pool of the polytransfused patients.

The prevalence of antibodies to human T-lymphotropic virus III was determined in acquired immunodeficiency syndrome (AIDS) risk groups by an enzyme linked immunosorbent assay and confirmatory tests in four different areas in West Germany. Twenty-four of 28 homosexual AIDS patients (86%), 24 of 33 homosexual patients with lymphadenopathy syndrome or AIDS related complex (73%), and 44 of 113 asymptomatic homosexuals at risk for AIDS (39%) were seropositive. In three groups of hemophiliacs, 8 of 35 in 1983 (23%), 25 of 65 in early 1984 (39%), and 19 of 23 in late 1984 (83%) showed positive results. Two sera from 36 polytransfused patients were also positive, whereas 36 selected blood donors, and 32 healthy laboratory and clinical personnel were all negative. Also no human T-lymphotropic virus III antibodies were detected in sera of 187 prostitutes in the Munich area.