Researchers trying to find out what killed the first person to receive a heart transplant from a pig have found an animal virus in the organ, but it is yet to be said that it played any role in the man’s death. Or not.
A Maryland man, 57-year-old David Bennett Sr., died in March, two months after an unprecedented experimental transplant. Doctors at the University of Maryland said Thursday they found an unwanted surprise – viral DNA inside pig hearts. They did not find any indications that the bug, called porcine cytomegalovirus, was causing an active infection.
But a major concern about animal-to-human transplants is that it could lead to new types of infections in people.
Because some viruses are “latent,” meaning they lurk without causing disease, “it can be a hitchhiker,” Dr. Bartley Griffith, the surgeon who performed Bennett’s transplant, told the Associated Press.
Still, “development is undergoing more sophisticated trials to make sure we don’t miss this type of virus,” said Dr. Muhammad Mohiuddin, scientific director of the university’s xenotransplant program.
The animal virus was first reported by the MIT Technology Review, citing a scientific presentation given to the American Society of Transplantation last month.
For decades, doctors have tried to use animal parts to save human lives without success. Bennett, who was dying and ineligible for a human heart transplant, underwent a last-ditch operation using a genetically modified heart from a pig to reduce the risk that his immune system would rapidly reject such a foreign organ. Will do it
The Maryland team said the donor pig was healthy, passed tests required by the Food and Drug Administration to check for infection, and was raised in a facility designed to prevent the animals from spreading the infection. Animal-providing company Revivcor declined to comment.
Griffith said that his patient, while very ill, was recovering well from the transplant, when one morning he became worse with symptoms similar to an infection. Doctors performed several tests to try to understand the cause, and gave Bennett a variety of antibiotics, antiviral medication, and an immune-boosting treatment. But the pig’s heart swelled, filled with fluid, and eventually stopped working.
“What was the virus doing, if anything, that could have caused his heart to swell?” Griffith asked. “Honestly we don’t know.”
The reaction also did not appear to be a typical organ rejection, he said, adding that the investigation is still ongoing.
Meanwhile doctors at other medical centers across the country are experimenting with animal parts in donated human bodies and are looking forward to conducting formal studies in living patients soon. It’s not clear how the pig virus will affect those plans.
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