Organ transplant is an effective therapy for end-stage organ failure but is currently limited by the shortage of human donors. The possibility that animals could provide an alternative source of donor organs and cells or tissue, a process known as xenotransplantation, has stimulated much debate, with general agreement that the pig is the most promising candidate animal, mainly due to the perceived lower microbiological risk in comparison to non -human primates. However, porcine zoonosis has been documented and human infection with porcine viruses may also occur following xenotransplantation with a theoretical risk of infection to the wider public [1-6].