Background: The use of pre-/post-exposure prophylaxis (PrEP/PEP) may interfere with routine HIV screening. As a result, blood services worldwide have adopted a variety of deferral policies to mitigate increased residual risk. In this study, we evaluated the operational impact of modifying the donor health questionnaire (DHQ) to include explicit questions to assess PrEP/PEP exposure.
Study design and methods: We conducted a retrospective study between June 2019 and October 2020 of all blood donors attempting to donate at Canadian Blood Services. Sixteen-months post-implementation, we summarized self-reported PrEP/PEP rates and their indications for use. We also assessed deferral rates and the sensitivity of using existing risk questions to defer people exposed to PrEP/PEP.
Results: Of 1,122,075 donations, 89 people (eight per 100,000 donations) reported PrEP (64%)/PEP (34%) use in the last 4 months. People exposed to PrEP were more likely to be men (94%) and taking PrEP for lifestyle reasons (87%). In contrast, indications for PEP use included occupational exposure (50%) and sexual assault (27%). Most donors who answered affirmatively to PrEP/PEP exposure were deferred (96%). If potential donors were not directly asked about their PrEP/PEP use, the majority would not have been deferred for any other reasons (PrEP 32/57 (56%) and PEP 15/30 (50%)).
Conclusion: Not all blood services have adopted direct questions to identify PrEP/PEP exposure; some rely on existing DHQ questions. In Canada, despite DHQ questions such as medication use in the last 3-days, more than half of people exposed to PrEP/PEP would not have been identified and deferred.
Keywords: PrEP; deferrals; donors; pre-exposure prophylaxis; residual HIV risk.
© 2021 AABB.