If the testing of blood is Canadian Blood Services’ first line of defense in protecting the blood supply, then donor screening is the second.

Strict donor screening ensures that each donor presents the least possible risk of transmitting diseases. Measures are also in place to protect the donor. Canadian Blood Services' screening procedures include physical tests (such as taking temperature and blood pressure) plus questions on health and high-risk activities.

Would-be donors, whose tests or answers indicate that they are at a higher risk for certain illnesses or medical conditions, are deferred from giving blood. Donors may be deferred for their own safety, and/or to protect the safety of the blood supply.

The Screening Process
Why Donors are Screened
Basic Eligibility
Look-Back/Trace-Back & Product Recalls