Transmission of Retroviruses by Transfusion of Screened Blood in Patients Undergoing Cardiac Surgery

We determined the rates of seroconversion to human immunodeficiency virus type 1 (HIV-1) and human T-cell leukemia virus Type I (HTLV-I) in a cohort of patients receiving transfusions of blood components screened for antibody to HIV-1. Preoperative and postoperative serum samples were collected from 4163 adults undergoing cardiac surgery who received 36,282 transfusions of blood components. The postoperative samples from all patients were tested for serologic evidence of HIV-1 infection, and those that were positive were compared with the corresponding preoperative samples. One case of HIV-1 transmission by transfusion of screened blood components was identified; two preexisting HIV-1 infections were found. Samples from 2749 patients were tested similarly for serologic evidence of HTLV-I infection; these patients received 20,963 units of blood components. Five new cases and two preexisting cases of HTLV-I infection were detected. The observed risk of HIV-1 transmission by transfusion was 0.003 percent per unit; the risk of HTLV-I transmission was 0.024 percent per unit. We conclude that there is a very small risk of HTLV-I infection from transfused blood products that have been screened for antibodies to HIV-1, but that it is nearly 10-fold higher than the risk of HIV-1 infection. (N Engl J Med 1989;320:1172–6.), THE transfusion of blood and blood components is a vital element of many therapeutic interventions, but it is not without the risk of untoward effects, including viral infections. In recent years there has been considerable concern about the transmission by transfusion of the retroviruses human immunodeficiency virus type 1 (HIV-1),¹ which causes the acquired immunodeficiency syndrome (AIDS), and human T-cell leukemia virus Type I (HTLV-I), which is causally associated with adult T-cell leukemia^{2 3 4 5 6 7} and with a progressive myelopathy.^{8 9 10 11} Voluntary deferral of blood donation by persons at risk for HIV-1 infection and screening of donated units for HIV-1 antibody since March….