Walter requested Francisca’s blood tests from the hospital and then began the search for compatible blood in the U.S. He tried blood center after blood center across the country before he was referred to the American Rare Donor Program in Philadelphia, a database of all rare-blood donors in America. Finally, he had located some suitable donors.

His relief was short-lived because, as Thomas or Peyrard could have told him, it’s a lot harder for blood to cross borders than it is for people. “You would not imagine how difficult it is when you have to import or export rare blood,” Peyrard says. “Your patient is dying, and you have people in an office asking for this paper and that form. It’s just crazy. It’s not a TV set; it’s not a car. It’s blood.”

Sometimes sending blood from one country to another is more than a bureaucratic nightmare. As Walter now discovered, the hospital in the UAE had a policy not to accept blood donations from outside the Gulf States, which meant that Francisca wouldn’t be able to use the blood he had found in America.

The situation looked bleak. But then, after a chance meeting with a colleague, Father Akata found out about a small general hospital in Cameroon, Nigeria’s neighbor to the east, that had set up a heart-surgery program with funding from the Catholic Church. Walter got in touch with the surgeons there, who confirmed that they could do the surgery if he could supply compatible blood.

The American Rare Donor Program contacted the South African National Blood Service, which had four suitable donors listed; however, one of these was unreachable, one wasn’t able to donate until later in the year, and two had been medically retired from donating. These are all common problems with rare donors. There are limits placed on how often people can donate. What’s more, keeping track of donors can also be a challenge—some get ill or die, and others move home without updating the blood services.

There were two units of compatible blood in South Africa’s frozen rare-blood bank, but frozen blood has a 48-hour lifespan, compared with four weeks for fresh blood. If it got held up at customs, or delayed for any other reason, it would be unusable by the time it reached the hospital in Cameroon. To use the frozen South African blood, Francisca would have to have her operation in South Africa. Walter was running out of options.

* * *

When he turned 18, Thomas was encouraged to donate blood for himself. There is now no frozen-blood bank in Switzerland, so his blood is stored in the rare-blood banks in Paris and Amsterdam. He travels to France to donate, avoiding the bureaucratic machinery that would grind into action if his blood had to be sent over the Swiss border to Paris.

The first urgent request came a few years after Thomas began donating, when he got a phone call asking if he would mind taking, and paying for, a taxi to the blood center in Geneva to donate for a newborn baby. That moment brought it starkly home to him how valuable his blood was. It was perhaps also the first intimation that the costs of donating would ultimately be his. Some countries do pay donors (and some pay more for rare blood) to encourage donations. But the majority of national blood services don’t pay, to deter donors with infections such as HIV.