For decades, the swine industry has been battling a virus that affects sows and their young, and a team of researchers at the Virginia-Maryland Regional College of Veterinary Medicine is on the front lines.
In 1987, pork producers first noticed a disease that causes reproductive failure in sows and respiratory diseases in piglets. Scientists later identified the cause: an emerging virus now known as porcine reproductive and respiratory syndrome virus. X.J. Meng, University Distinguished Professor of Molecular Virology, has been working to improve vaccines against the swine disease since the 1990s.
“Today, vaccines against porcine reproductive and respiratory syndrome virus are being used worldwide,” Meng said. “If the virus infecting a swine herd is genetically similar to the vaccine virus, then the vaccine performs well. Unfortunately, many strains of virus infecting pigs today are genetically different from the one used to create the vaccines.”
Scientists have known about this problem for some time. In 1991, researchers discovered that the virus infecting pigs in the United States was a variant strain of the virus causing similar problems in Europe. Recently, the virus has caused high fever diseases in pigs in China, leading to high mortality rates and significant economic losses.
“We need to develop a better and more efficacious vaccine against the virus,” Meng added.
The disease is now one of the most economically important for the global swine industry, causing pork producers to invest more money into raising pigs and reducing the number of piglets from the onset. Meng estimates that the virus has increased the cost of pork production by $18 per head. This could mean up to $4.4 million in annual profit losses for Virginia’s swine industry.
Meng hopes to not only improve existing vaccines against the virus but also to develop better preventative measures against the disease. His laboratory previously cloned the first U.S. strain of the virus to better understand its biology in order to develop a second-generation experimental vaccine against it.