Recipients of untested blood from donors who at a subsequent donation were positive for HIV antibody by enzyme immunoassay (EIA) were evaluated, whether the result on Western blot (WB) assay was negative (EIA+/WB-) or positive (EIA+/WB+). For 109 EIA+/WB- donors, 78 recipients were tested for HIV antibody, and 3 (4%) were positive. Two of the three anti-HIV-positive recipients had clotting disorders, and the other had been massively transfused; in each of these three cases, subsequent test data exonerated the EIA+/WB- donor. For 101 current EIA+/WB+ donors, 35 recipients were tested for HIV antibody, and 13 (37%) were positive. For donors subsequently found to be EIA+/WB+, the rate of isolation of HIV was the same whether the recipients were anti-HIV-positive or anti-HIV-negative (each, 5/6). While recipients of blood from donors subsequently found to be EIA+/WB+ were at substantial risk for HIV infection, regardless of the donor's subsequent HIV culture result, risk of HIV infection was not demonstrated for recipients of blood from donors later found to be EIA+/WB-.