It evolves quite rapidly as it moves from country to country, so studying its genetic make-up ought to reveal the country of origin. One problem, however, is that a number of countries do not admit to having the disease and do not send samples to the experts at Britain's Institute for Animal Health, who have been studying the different strains involved. At the institute, scientists have already discovered the virus is almost identical to one that has been causing a pandemic disease throughout much of Asia for the last few years. It was the first time they'd had it for 70 years. The virus spread to South Africa and South America, so this is a very virulent form of the virus.
Vaccines do exist against the disease, but they bring their own problems.
A vaccinated animal produces antibodies in its blood system that protect it against the disease. But an infected animal produces the same antibodies. So a country testing imported animals would not easily be able to tell if they had the disease of if they had simply been vaccinated. That problem could be overcome, said Professor Stuart, but it would take time. It also takes several weeks for the vaccine to become effective in an animal, he said.