Another weapon has been found in the fight against foot and mouth disease.
Researchers at the Plum Island Animal Disease Centre in the United States recently announced a new vaccine to stop the spread of the disease that can have serious economic impacts on livestock.
Biosecurity efforts continue to keep North America free of the virus, which is very contagious and affects ruminant animals with cloven hoofs. It continues to be a major problem in Asia, Africa and South America.
“FMD spreads like fire. It flies through the air. It goes with every track, with every movement. And it jumps in all species. So cattle, sheep and goats — and pigs in particular, it sheds a lot of virus,” said Volker Gerdts, director of the Vaccine and Infectious Disease Organization — International Vaccine Centre at the University of Saskatchewan in Saskatoon.
The new vaccine does not require the use of the live foot and mouth disease virus for vaccine production, but uses synthetic biology to join together numerous parts of the virus genome to produce a vaccine.
The procedure involves the modified picornavirus 3C protease, which cuts up the parts of the virus to produce an FMD virus-like particle.
Once the vaccine is injected into livestock, the virus-like particles fool the immune system into thinking it has been infected by a live FMD virus, but without side effects of sickness or killing host cells. Animals are then able to develop immunity against the FMD virus.
“Essentially they have found a way of assembling parts of the virus without really using the whole virus and now they can use that as a vaccine. So it’s safe, it doesn’t have the infectious virus in it, and it allows them to also differentiate vaccinated from infected animals,” said Gerdts.
“You can still keep your status of being FMD-free, although you use this vaccine.”
And because the new FMD vaccine is free from the risks associated with inactivated virus vaccines, it is safer to produce and can now be manufactured in the U.S., which by law is prohibited from being produced there.
Researchers at the Plum Island Animal Disease Centre have indicated the main risk of manufacturing FMD virus previously was the risk of accidently releasing it.
“It allows them to rapidly develop the vaccine by essentially not using live virus but assembling something that looks like the virus and it still allows them to differentiate vaccinated from infected animals,” said Gerdts.
“What this (Plum Island Animal Disease Centre) group shows is a really, really sophisticated way of manufacturing future vaccines that will never have a live virus in them. So that’s a nice milestone to have, and it’s also DIVA (Differentiating Infected From Vaccinated Animals) compatible for trade. That’s very important,” he said.