A researcher at the Virginia-Maryland College of Veterinary Medicine at Virginia Tech has received at a two-year, $150,000 grant from the U.S. Department of Agriculture’s National Institute of Food and Agriculture to develop a new vaccine against porcine epidemic diarrhea virus. The virus, first discovered in North America in 2013, has resulted in at least 10 million pig deaths, according to the United States Department of Agriculture (USDA).
“The process starts in the laboratory here using molecular techniques to make genetic changes to the virus and test it in small-scale tissue cultures in the laboratory,” said Adam Rogers, Ph.D., a postdoctoral associate in the Department of Biomedical Sciences and Pathobiology. “If we find a mutation or mutations that will make the virus non-pathogenic, then we will move onto an animal test. We are starting with the emergent American strain of the virus so that we will end up designing a vaccine specifically targeted to control the disease here.”
Rogers’ mentor X.J. Meng, University Distinguished Professor of Molecular Virology, said that even though the researchers were using the emergent U.S. virus strain, a new vaccine based on the U.S. strain would “most likely work in Asia as well because the virus strains in Asia and the United States are very similar.” In 2013, Meng led a team of researchers to identify the origin and possible evolution of the virus when it had only been known to exist in the United States for just a few months. They determined that the virus, which belongs to the coronavirus family, likely originated from China, according to Virginia Tech.
Although recent to North America, researchers have known about the virus since it was first identified in Europe in the 1970s, Rogers said. Pork producers have learned more about the virus since its identification in the United States and are now better at spotting symptoms and isolating infected piglets from the rest of the herd, he added. They have also improved biosecurity measures to help prevent the virus from spreading from farm to farm.
“However, an effective vaccine will be much better at keeping the virus under control,” Rogers said.
The USDA has granted conditional licenses to two vaccines, but the efficacy of the two conditionally-licensed vaccines in the United States remains to be seen, according to Virginia-Tech. Meng said there are also attenuated live vaccines available to pork producers mostly in Asia, but these have not successfully controlled the disease there or in Europe.
“This is a prestigious grant,” Meng explained. “Adam is the principal investigator on this grant, and it has given him an opportunity to learn how to write a successful grant, manage it, and complete the training that will help him become an independent academic researcher.”