In September , Canadian Blood Services implemented sexual behaviour-based screening in our donation process. This change removed questions about sexual orientation that previously prevented many sexually active gay, bisexual, queer, and other men who have sex with men, and some trans people, from donating blood.
We now ask all donors the same questions about sexual behaviour, regardless of sexual orientation or gender. The three-month wait is in place to reduce the chances of our tests missing any very recently acquired infections. If the answer is yes, they are asked if they have had anal sex in the last three months. The three-month wait is in place to reduce the chances our tests may miss any very recently acquired infections. Per sex act, receptive anal sex has a significantly higher chance of HIV transmission than vaginal or oral sex.
The acquisition of any new sexually transmitted infection HIV, Hepatitis B, or Hepatitis C increases with the number of potential exposures, i. Our screening tests can miss a very recently acquired infection. This time frame is called the window period and is approximately three months. PrEP or pre-exposure prophylaxis is a highly effective combination of medications that prevents HIV infection by the person taking it. PrEP use is recommended to maintain sexual health.
There is currently a four-month deferral period in place for people who use PrEP. The current challenge facing blood operators is that the medications used for PrEP affect the ability of screening tests to detect low levels of HIV. Canadian Blood Services relies on accurate performance of HIV tests as part of its multi-layered approach to safety.
We are currently working with external experts in HIV testing to further understand the impact of antiretroviral medications on tests and determine how to minimize the duration of deferral for donors using PrEP.
