MIT Technology Review reported that a porcine virus infection could have contributed to the death of the first patient who received a heart transplant from a pig organ.

In early January of this year, David Bennett Sr, who had severe heart disease, received a genetically modified pig heart — a significant milestone in animal-to-human transplants, or xenotransplantation. He passed away in March. The hospital where the procedure was performed initially stated that the cause of death was unknown.

Bennett's transplant surgeon revealed last month in a webinar that the heart was infected with porcine cytomegalovirus, a virus that does not infect human cells but can harm the organ. According to a German study, virus-free hearts transplanted into baboons survived much longer than virus-infected hearts.

It is worth mentioning that Bennett received a heart from Revivicor, a biotechnology company that creates genetically modified pigs. 

The pigs were supposed to be virus-free, but this particular virus can be difficult to detect, according to Joachim Denner, a virologist at the Free University of Berlin, in an interview with MIT Technology Review. 

The company declined to comment on the heart and virus to MIT Technology Review.

It's unclear how the virus played a role in Bennett's death. However, if he died as a result of the virus rather than his body rejecting the organ, researchers working on xenotransplantation are unlikely to have to rethink their overall strategy. "If this was an infection, we can probably prevent it in the future," said transplant surgeon Bartley Griffith during his presentation.