Regulatory Decision Summary for Change in Blood Donor Deferral Criteria for Risk-Based Sexual Behaviour Criteria

Previous to this submission, gbMSM had to wait a three-month period (deferral) since their last sexual contact with other men before being able to donate blood. Female donors who have a male partner that had sex with another man in the last 12 months were also deferred for three months from blood donation.

Screening questions for deferral had been put in place due to the high prevalence of HIV in gbMSM community. These questions are viewed by some in the gbMSM community as discriminatory, as not all gbMSM pose the same risk for HIV infection. 

In this submission, CBS replaces these questions for gbMSM with sexual behaviour-based questions that apply to all donors. The 3-month deferral applies to all donors who would have had anal sex with a new or multiple partners in the last three months.

It is important to note that CBS performs testing on every blood donation for HIV. The risk to the blood safety is therefore mainly due to donations that could occur during the window period (time between when a donor may be infectious and when the test would be able to positively detect HIV). The window period is now 8 days for HIV. 

Currently, various screening approaches are being used by blood regulatory agencies internationally. For example, gbMSM are deferred for 3 months, as in Canada recently, in the US and Australia. The UK and Israel have adopted screening tools that use sexual behaviour based screening criteria, similar to the new CBS criteria.

Three major reviews of epidemiologic studies, including the UK’s FAIR (For the Assessment of Individualised Risk) report, and the CBS’s Engage study identified the sexual behaviour activities with a higher risk of HIV transmission, such as anal sex with new or multiple partners. These higher risk sexual behaviours are now part of the deferral criteria for all blood donors.

CBS did risk modelling to estimate the residual HIV risk amongst blood donation. Based on the modelling study, the estimated risk would change from 1 per 25.9 million donations to 1 per 20.7 million donations with the new screening criteria based on sexual behaviours. The overall very low risk with the proposed screening criteria (1 per 20.7 million donations) indicates that the change in risk following blood transfusion is in reality not meaningful or significant and will remain very low.

Validation of the proposed screening questions in terms of understanding, clarity, and acceptability was performed in two studies that were part of the gbMSM Research Program. Participants considered the questions acceptable, and understanding the rationale for the questions would be important for decreasing discomfort in responding to the questions. The rationale for questions will be shared at the time of donation.

On April 13, 2022, Health Canada convened a group of external experts to seek technical advice and recommendations regarding CBS’s proposed change to blood donor screening. The expert group agreed unanimously to support the implementation of the sexual behaviour based screening criteria for all blood donors. 

Taking into account the strengths and limitations of the available data, the proposed post-implementation follow-up plan by CBS and the advice of the group of experts, Health Canada concludes that the use of sexual behaviour based deferral criteria for all blood donors is acceptable under the following conditions:

• That CBS will implement all the elements of the Post-Implementation Monitoring Plan that was submitted.
• That CBS will provide Health Canada with an overall assessment of the cumulative 5 years monitoring data post-implementation.
• That CBS will submit the guidance for the proposed sexual behaviour based deferral questions to Health Canada. This guidance will be part of training material for the staff that does screening and will be in the information material for the donors.