When AIDS emerged in the early 1980s, the risk of acquiring HIV from a transfusion was approximately 1.1%. The U.S. Food and Drug Administration (FDA) introduced educational and deferral policies in 1983, which included deferring men who have sex with men (MSM). The mitigation strategies reduced the risk of transfusion-transmitted HIV to 0.2%. The addition of a donor antibody screening assays and an indefinite ban for MSM further reduced the risk to 0.0025%. By 2015, advanced nucleic acid tests decreased the risk of acquiring HIV to 1 in 1.6 million donations, and the FDA reduced the deferral period for MSM to one year. In 2023, the FDA published new guidance for HIV based on individual risk behavior. All donors who report a new sexual partner in the past three months or more than one sexual partner in the past three months are now asked about anal sex in the past three months and are deferred based on these activities or if they are taking antivirals to prevent or treat HIV. In order to predict the effect of these new changes on the U.S. blood supply, researchers modeled the number of donors who would be deferred using (1) 50 published articles and three national surveys on sexual behavior and (2) data from the U.S. National Survey of Sexual Health and Behavior from 4528 individuals. Based on both analyses, the estimate for new or multiple sexual partners was about 6%, and the percent of U.S. donors predicted to be deferred based on individual behaviors was 1.2% (with slightly different but overlapping confidence intervals). The model estimates minimal impact of the change for deferrals based on individual risks compared to time-based deferrals. The FDA will continue to monitor the blood supply and donor deferral policies.
Reference:
