Bone Marrow Awareness Day, a short walk from where the transplants happen

This is the second Bone Marrow Awareness Day in four days, and it sits here on purpose. Yesterday the route reached the hospital where British Columbia's adult bone marrow transplants are done. Today Jeana Moore does not move. In her own words: "I stay where I am to educate about donors, transplants, how and why they should join."

In practice that means a long day of the same handful of questions. Whether it hurts. Whether it costs anything. What HLA is, and why a sibling is not automatically a match — each full sibling has about a one in four chance of being a full HLA match. Why someone can sit on a registry for years without ever being called, and why that is still worth doing. She will explain that in Canada the registry is run by Canadian Blood Services and takes people aged 17 to 35, that registering starts with eligibility questions online and a swab kit that arrives by post, and that readers in the United States go through NMDP instead.

She will also be clear about what she is not. The Jada Bascom Foundation refers people to registries; it is not one. It does not perform HLA typing, does not collect cells, does not mail kits and does not decide who is eligible. Nobody is signed up at a walk stop. The value of a day like this is narrower and more useful than that: the questions get answered by a person rather than a web page, and the person answering them has been on the receiving end of the answer.

About a quarter of patients find their match inside their own family. The rest have to look outside it, sometimes on the other side of the world — over 40 million registered donors across over 80 participating countries, which still turns up a match for a patient in Canada only about half the time. Jada's donor was a man in Germany who had registered before she was born and was not told her name.