It’s time to crunch the numbers again to determine the current cost of porcine reproductive and respiratory syndrome (PRRS) to the US pork industry.

Derald Holtkamp, associate professor of veterinary diagnostic and production animal medicine at Iowa State University, is undertaking the three-year study to determine if the management changes that pork producers have instituted on-farm over the last few years to fight the virus have cut the monetary losses the industry has sustained since the mid-1980s when PRRS was first identified in the United States.

Dr. Holtkamp will be updating a study that he originally conducted in 2012 that pegged the pork industry's annual PRRS loss at $664 million which equates to about a 9.9 million pig loss per year. This level of loss from PRRS is far more devastating than Porcine Epidemic Diarrhea virus (PEDv), even at its worst, he said.

The virus that causes PRRS has shown a knack for evading immune responses in pigs and can infect pigs of any age.

"It's a clever virus," Holtkamp said. "It changes rapidly to keep a pig's immune system from fighting it off. We have vaccines, but their efficacy is often limited."

The virus has posed a recurring challenge for the pork industry with 20 to 40 percent of breeding herds experiencing outbreaks in a given year, he said.

The National Pork Board set a goal to cut the annual economic impact of PRRS by 20 percent by the year 2020. Since Holtkamp’s previous study, a number of management practices to control the disease have been implemented by producers. The updated study should offer insight into how effective those efforts have been toward achieving the 20 percent reduction, he said.

Producers have tested several strategies to fight the virus, including vaccines and biosecurity measures to stop the virus's spread among the most susceptible pigs. Holtkamp compares those strategies to “taking away all the dry wood so the fire runs out of fuel.”

Holtkamp said the updated study will draw on a combination of data supplied by pork producers and surveys and diagnostic data from local veterinarians.

"This is a way to measure the progress we've been making against the pathogen and the disease it causes," Holtkamp said. "We'll be able to see if we're moving the ball on PRRS. I think we are and will continue to do so."

Holtkamp's team will release an update on the economic effects of the virus quarterly for three years.