“I was always reluctant to get Factor IX regularly on prophylaxis. That’s why I started only six years ago. It is sometimes really troublesome to inject the protein into your veins twice or three times a week and, most importantly, I was afraid of getting a more serious human infection such as AIDS which would make my life even more difficult.”

Born with hemophilia B I have only 1.5% of the clotting Factor IX in my blood. My parents were always anxious in case I got hurt. But I understood their worries perfectly, knowing that I would harm my body by not paying attention.

In the early fifties it was very difficult to treat my condition. Minor injuries heal after a few days, but to stop a major bleeding there was no other treatment available than making a full blood transfusion. At the age of six I had my first big one. I don’t know how it happened – maybe a misstep. The bleeding expanded and became repeated; 20 years later it destroyed the meniscus in my knee. Walking and cycling have been more difficult since, and today I can’t take the stairs without the risk of getting a bleed again.

Once I had a bleed in my upper leg. The muscle was so big that I didn’t notice it for days and felt I was going to my very end. It took weeks before my body was relieved from the blood and months before the muscles worked normally again. I can’t do sports which may require spontaneous movements such as tennis. Traveling is difficult too because the Factor IX protein needs to be stored at low temperature and the therapy is not easily available in every country.

For 14 years of my life I was treated with pure blood. Factor IX replacement became available in 1967, a huge advantage, but it still requires frequent intravenous administration and carries the risks associated with human blood products. 20 years ago one bad batch was enough for me to get a hepatitis C infection.