5 Ways PRRS Made Us Better

( National Pork Board and the Pork Checkoff )

This is the second story in a three-part PRRS series.

Although porcine respiratory and reproductive syndrome (PRRS) is not a new disease, it continues to affect pig farmers and is the No. 1 cause of economic impact in the U.S. swine industry. Still, industry experts say the disease has made us better. 

“PRRS has challenged us for sure,” says Reid Philips, DVM and PRRS technical manager for Boehringer Ingelheim. “It has made us work harder, but along the way, it has made us better in all areas of management and biosecurity.”

An ongoing Pork Checkoff PRRS project, conducted through Iowa State University by Dr. Derald Holtkamp, provides semi-annual updates on the disease’s cost to the U.S. swine herd. Based on a five-year moving average, annual productivity losses due to PRRS fell $83.3 million from October 2010 ($663.91 million) to October 2016 ($580.62 million), according to a 2017 interim report. According to the National Pork Board’s strategic plan, the industry’s goal is to decrease PRRS’ impact 20% by 2020 from the 2010 baseline to $531.13 million.

“This decrease is evidence of our ability to apply what we have learned and improve our efforts to control PRRS,” Philips says. “It signifies an improved understanding and application of tools to control PRRS virus on the farm – vaccination protocols, biosecurity protocols, pig flow protocols and other management protocols – those things that are targeted at controlling virus on the farm are paying dividends and are working. That’s good news.”

There’s no question PRRS strengthened biosecurity in the U.S., says Montserrat Torremorell, DVM and associate professor in the Department of Veterinary Population Medicine at the University of Minnesota. Not only did it help producers improve methods to keep disease out, but it also taught the industry valuable lessons to help the fight against all diseases.

1.    PRRS improved communication. 
When porcine epidemic diarrhea virus (PEDV) came into the U.S. in 2016, the Morrison Swine Health Monitoring Project (MSHMP) was in full force because of PRRS. 

“Because of this system already in place, we were very effective about communicating and quantifying how much PEDV we had to the point USDA used data generated through MSHMP,” Torremorell says. “This wouldn’t have been possible without PRRS.”

She says PRRS also brought universities and industries together from a research standpoint. No one has all the answers, but together, the system is stronger when a disease is tackled from a variety of angles.

2.    PRRS fostered benchmarking.
Years ago, little to no sharing took place between production systems, says Daniel Linhares, DVM and assistant professor in the College of Veterinary Medicine at Iowa State University. 

“Today there are many projects out there based on benchmarking with people really sharing their frustrations as well as their success stories. With that, the whole industry wins, right?” he says. “If you are Production System A and you share with Production System B and help them do better, sure he’s your competitor, but at the end of the day, you share the same region. The less PRRS virus in your region, the less challenges for both of your systems.”

3.    PRRS developed new tools for the toolbox.
To better detect PRRS virus, new diagnostic tools have been developed along the way, Torremorell says. For example, using oral fluids for diagnostic testing and more recently, processing fluids, have helped producers obtain samples more conveniently and from a larger population of pigs. 

“This has been a game-changing milestone – to help us better understand the status of PRRS between phases of production and between populations of pigs,” Philips says.

In addition, biosecurity measures such as air filtration and transport wash-dry systems have helped producers prevent introduction of disease into the farm. 

Now some of the models are more network-type models that challenge us to look at the disease at the regional level, and not at your single farm level. 

4.    PRRS reinforced that immunity matters.
Immunity matters and many of the programs/protocols today use a vaccine to achieve and maintain a population-based level of immunity, Philips says. 

The vaccine alone is effective and has a bioeconomic benefit, he adds, but it’s best applied with a complimentary package of components for PRRS control – biosecurity, strategic pig flow and good pig management practices. 

“We’ve learned the importance of a systematic approach to control PRRS over the years and it’s improved our ability to control this virus,” Philips says. “One or two of these things can be beneficial. But if we can package them all in a holistic, whole-herd, systematic approach, that’s our best effort and provides our best principles for control.”

5.    PRRS taught people to think beyond the pathogen.
Over the years, PRRS has taught the industry to consider the whole ecology of interactions – between the pig, between the pathogen, between the environment and more.

“We learned how to take a more holistic approach,” Linhares says. “It’s not just about developing the best vaccine and winning the game. It’s about improving diagnostics, improving biosecurity and training workers to do the right thing at the barn level. It’s about changing the whole ecology.”

The industry does not have to be held ransom by PRRS if you are willing to invest in resources and use the science, says Scott Dee, DVM and director of research for Pipestone Veterinary Services.

“Our system runs at a very low level of infection each year and every time we get an infected farm, we immediately go into elimination mode to get the virus out,” Dee says. “There are protocols, there are tools and there is scientific evidence and data that says you can deal with this thing. We’ve learned how to live with it.”

Dee says PRRS has caused Pipestone and similar companies to develop a standard operating protocol for managing infected farms. 

“PRRS made us put together a plan – a consistent plan we follow the same way every time,” Dee says. “It’s made us better scientific thinkers as far as how we deal with problems. That’s clearly affected how we handled PEDV and how we’re thinking about ASF [African swine fever]. Because of PRRS, we’re much better prepared to handle those diseases – the one that’s made it in and the one that hopefully won’t. It’s just made us all better.”

Did you miss part one in the series? Read PRRS: Deciphering the Mystery Disease.

More from Farm Journal's PORK:

Protect Your Pigs from PRRS: Use All the Tools in Your Toolbox

Uncovering Breeding Herd Vulnerabilities to PRRS