I'd like to. Thank you for that question.
I'm going to make a general comment, and then Dr. Devine can provide a little bit more of the specifics. I think it is important for committee members to appreciate that the clinical decision-making to support an organ donation or a stem cell transplant is very different from the clinical decision-making to give somebody a transfusion.
We collect close to a million units of blood a year. About 1.5 million transfusion events happen in Canada every year, and if a physician needs to choose a unit of blood, typically there's a large selection to choose from, so we can easily defer 3% of the blood donors and still meet the needs of all the transfusion patients.
For stem cell donors and patients, and certainly for organ transplant patients and donors, there's a very different relationship. Getting the organ is a life-saving event and often it's the only organ available, and if the patient doesn't get it, he or she might well die from the underlying disease. The whole notions of risk-based decision-making and clinical decision-making are very different.
I'll let Dr. Devine clarify again the situation with the stem cell donor, but if an organ donor who may have travelled to one of the Zika-risk countries comes back to Canada and is, unfortunately, killed in a motor vehicle accident within that 21-day window, the physician will make a clinical decision as to whether that organ is potentially going to save a life at the risk and very low likelihood of transmitting Zika, probably in the order of one in three million or four million.
The set of risk-based decisions for organs and stem cells is very different from that for blood, and it is based purely on the availability of the resource to match the patient's needs. Again, I think we'll clarify for the committee the specifics on that stem cell case.