Condition
High-risk sexual behaviour is that which puts the donor at risk of sexually-transmitted infections (STIs) which may then be transmitted to the recipient/patient. This risk occurs because the donor themselves currently participate in high-risk behaviour, or currently have sex with someone from a high-risk background.
The aim is to reduce the risk of 'window period' transmissions, where a donor is infected with (for example) HIV, but the infection is too recent to be picked up by screening tests and the infection is passed to the patient. For this reason, donors who report high-risk sexual behaviour in the past, but do not do so currently, should be allowed to donate.
Furthermore, since peoples’ sexual practices change over time, and since the window period for HIV detection is less than three months, a sexual history is not necessary at the time of recruitment and need only be taken from potential donors at the time of confirmatory typing and workup assessment.
The traditional method of defining high-risk behaviour is to ask donors about recent sexual contact with a partner in a high-risk group for STIs that can be transmitted via HSCT, with “high-risk” groups defined by epidemiological data. For HIV – considered the most impactful STI – the prime example of this method is to ask donors about recent sexual contact with a man who has sex with men (MSM).
One limitation of the traditional approach is that MSM in an ongoing relationship with a single partner are effectively attributed the same risk as MSM with multiple new partners. This lack of distinction between different sub-groups of MSM contributes to stigma against MSM as a wider group.
An alternative approach being adopted by a number of blood and tissue establishments is known as “gender-neutral” or “individualised” risk assessment. At its most basic, this approach replaces an epidemiological definition of high-risk sexual behaviour with one based on exposure to new and/or multiple sex partners.
While older iterations of this approach raised safety concerns for countries where HIV is highly concentrated among the MSM population, more recent frameworks have included additional activity-based risk criteria that mitigate those concerns while remaining “gender-neutral”.
For this guideline, high-risk sexual behaviour is defined as any of the following:
- More than 1 sexual partner within the past three months, AND anal sex with any of those partners.
- Anal sex with a new sexual partner within the past three months (a new partner is someone with whom one has not previously had sex with, or a previous partner with whom one has restarted a sexual relationship).
- Any type of “chemsex” activity within the past three months, including with the use of stimulant drugs.
The WMDA considers this approach to gender-neutral screening to be well-suited to assessing stem cell donors, where the possibility of STI risk must be balanced against the limited donor options available. In particular, gay, bisexual, and other men who have sex with men should not be excluded or deferred as donors based on time since last sexual contact with another man.
Individual at Risk
Recipient
Guidance at RECRUITMENT
ACCEPTABLE
Guidance at CT/WORK-UP
DISCLOSE RISK TO TRANSPLANT CENTRE
However, a donor identified to be engaging in high-risk sexual behaviour may be acceptable at the discretion of the requesting transplant centre. In such cases, the transplant centre should be told that the donor meets criteria for high-risk sexual behaviour as outlined above.
Justification for guidance
With use of modern screening techniques, the risk of unintended transmission of an infectious disease is very small. Stem cell donors undergo in-depth medical and sexual health questionnaires, and will have a face-to-face interview with donor centre staff, allowing ample opportunity to identify those donors at increased risk of contracting a window-period infection. In many cases, the benefit to the recipient of receiving a donation will vastly outweigh the risk of transmitting an infectious agent. Further, since sexual behaviour changes over time, assessment of such risks at time of recruitment is not helpful.
For these reasons, the employment of fixed deferral periods for certain groups deemed to be at a higher risk of developing window period infection is not recommended by the WMDA.
Furthermore, WMDA advocates for applying a health equity lens to the screening of donors for high-risk sexual behaviour, and not simply deferring donors for being (for example) MSM. Gender-neutral screening for high-risk sexual behaviour, conducted at CT and work-up, balances the need to identify donors who are at higher risk of window period infections while minimising donation-related stigma faced by gay, bisexual, and other men who have sex with men.
Guidance regarding pre-exposure prophylaxis (PrEP) or post-exposure prophylaxis (PEP): forthcoming