Nondisclosure of use of antiretroviral medications in Canadian blood donors.

Abstract

Introduction: Donors are deferred if they are on antiretroviral medications (ARV) as post-exposure or pre-exposure prophylaxis (PEP or PrEP) for human immunodeficiency virus (HIV). We assessed donor compliance by measuring ARV levels in selected anonymized donor samples collected from September 22, 2022 to December 31, 2024, almost all after the introduction of sexual risk behavior screening.

Methods: EDTA plasma samples collected at the time of donation (retention samples) were retrieved, frozen, and shipped for measurement of tenofovir and emtricitabine. Samples were from randomly selected first-time male donors in large urban areas (n = 520), syphilis (n = 133), or HIV (n = 6) confirmed positive donors, and donors deferred for PEP or PrEP use on a previous donation attempt who returned to successfully donate (n = 225 tests, 115 unique donors). We compare our results to international studies.

Results: All samples from first-time male donors, HIV-positive donors, syphilis-positive female donors, and female donors previously deferred for PEP or PrEP were negative. Three of 110 male syphilis-positive donors (2.7%) and 14 of 85 male donors previously deferred for PEP or PrEP (16.5%) were positive for ARV. Eleven of these donors were tested multiple times, and 10 were positive more than once.

Conclusion: Results on syphilis-positive male donors were similar to findings in England and the Netherlands. Noncompliance with criteria for ARV use was high in male donors previously deferred for PEP/PrEP. Messaging regarding recipient risk is particularly difficult in this group, since it is at odds with the reduction in individual HIV risk.