Modeling US blood donor deferrals under a policy of individual risk assessment for HIV risk sexual behavior

Abstract

Background: In May 2023, the Food and Drug Administration (FDA) released final guidance for blood donor eligibility that recommended the elimination of 3-month deferral for men who have sex with men (MSM) and the related deferral for women who have sex with MSM. In its place, FDA introduced an individual risk assessment policy of asking all presenting blood donors, regardless of sex or gender, if they have had a new partner or more than one sexual partner in the last 3 months and deferring those who also report anal sex (penile-anal intercourse) during this period. We modeled the possible impact of this policy on the US blood donor base.

Study design and methods: We developed a computational model to estimate the percentage of blood donors who would be deferred under a policy of individual HIV risk assessment. The model incorporated demographic information about donors and national survey data on HIV risk behaviors and included age and sex distributions and dependencies.

Results: Our model estimates that approximately 1.2% of US blood donors would be deferred under the individual HIV risk assessment paradigm.

Discussion: The model predicts a relatively minor effect of replacing the time-based deferral for MSM with individual risk-based deferral for sexual behavior. As US blood centers implement this new policy, the effect may be mitigated by donor gains, which warrant further study. The new policy is unlikely to adversely affect the availability of blood and blood components.

Keywords: HIV risk assessment; MSM deferral; anal sex; blood donor deferral; blood donor loss; modeling; sexual partner; transfusion.

Figure 1:

Donor Individual Risk Algorithm and Key Data Sources. TTIMS, Transfusion-Transmissible Infections Monitoring System; NHANES, National Health and Nutrition Examination Survey; NSSHB, National Survey of Sexual Health and Behavior

Figure 2:

Numbers of donors by age and sex from the TTIMS program, which represents approximately 60% of the blood supply. TTIMS, Transfusion-Transmissible Infections Monitoring System

Figure 3:

Mean Proportion of Having New or Multiple Sexual Partners for Men and Women in the U.S. by Age, Based on NHANES (2015–2016).

Figure 4:

Input Distributions for Anal Sex Rates in the Past Year for Men and Women in the U.S. by Age Based on NSSHB (2009).

Figure 5:

Estimated Mean Percent Donor Deferred Based on NSSHB (2022). The mean proportion of donors that would be deferred for each age group was estimated. NSSHB, National Survey of Sexual Health and Behavior

Figure 6:

Probability Distributions of Donor Deferral Estimates for the U.S. TTIMS blood donor data and the input distributions of sexual behaviors were used to estimate the percent donor deferral and its uncertainties under the individual HIV sexual risk-behavior donor deferral policy. Mean value (1.2%) of deferred donors estimated from using TTIMS (2021), NHANES (2015–2016), and NSSHB (2009) data was the same as that estimated from using the TTIMS (2021) and NSSHB (2022) data. TTIMS, Transfusion-Transmissible Infections Monitoring System; NHANES, National Health and Nutrition Examination Survey; NSSHB, National Survey of Sexual Health and Behavior