The long-term future of the North American swine industry and the swine veterinary profession will depend on how the industry chooses to manage PRRS today.
That’s the opinion of University of Minnesota swine veterinarian Scott Dee, DVM, MS, PhD, Dipl; ACVM.
“We are at a crossroads,” says Dee, also vice president of the American Association of Swine Veterinarians and a member of the AASV executive board. “I believe we have to eliminate this virus from the continent. Despite the opinion of some of our members, I believe there is no golden bullet vaccine tucked away in a freezer and, in fact, one may never be developed in our lifetime.”
His remarks were made during a presentation at the recent University of Minnesota Allen D.
Leman Swine Conference in St. Paul, Minn. In that presentation, Dee discussed the future of PRRS and what he thinks the next 10 years might bring in the fight against this disease syndrome.
He also proposed a new four-point plan to help the pork industry and the swine veterinary profession to move forward toward the eventual eradication of PRRS from North America.
“The veterinary profession must lead the way to large scale, sustainable eradication of this disease,” says Dee. “However, it will take significant change in the industry and the veterinary profession to make this happen. In order to move forward, we must dispel perceptions of conflict, rebuild a high level of trust amongst ourselves and unify the swine veterinary profession and its respective industries. I foresee the need for a four‑point plan to accomplish this goal.”
“In my opinion, one way to begin to re‑build trust and manage conflict is to promote complete disclosure and transparency throughout the organization,” Dee says. “Simply put, we need the facts. Following my election to the AASV executive committee, I was told by two friends that I should begin to disclose my consulting fees and sources of research funding in order for the membership to objectively assess my statements, actions and publications.
“I think this is very wise advice, and I believe that disclosure should be practiced by all members of our organization, and it should extend beyond sources of consulting fees and research dollars, to include the disclosure of patent ownership since the patent issue is so central to today's discussion.”
Dee suggests that those interested in learn-ing about existing PRRS patents, should check the Internet home page of the U.S. Patent and Trademark Office (USPTO) and conduct a PRRS search. That page can be assessed at: www.uspto.gov/.
University of Minnesota PRRS expert Scott Dee has called for the swine veterinary profession, academia and companies to join together as a team to attempt eradication of PRRS virus.
“The last time I checked, I found that 37 PRRSV patents existed, involving many AASV members and universities. The inventions covered by these patents ranged from patents on individual viral isolates, diagnostic tests, methods of growing and attenuating PRRSV for the purpose of vaccine production, host susceptibility factors, viral proteins and others.
“I must confess that I was quite surprised by this information, and was very interested to learn that there is more than one patent involving an invention for virus propagation and vaccine production. I suggest that interested members seek out the USPTO Web site, get the facts and then make your own informed decision.”
Dee believes that this could be an important step in disclosure and transparency. “Hopefully, disclosure of this information will allow us to get the facts and to objectively assess the statements and actions of others, leading to the eventual rebuilding of a profession‑wide trust and the building of teams.”
Dee says that swine practitioners, university researchers, biological, pharmaceutical and genetic companies, need to “unite and develop mutually beneficial ways to share technologies and profits. We don't need any more lawsuits, especially over patents. Too much time has
already been wasted in the courtroom.”
The AASV executive committee, according to Dee, has been in discussions with industry partners in an effort to explore the flexibility of PRRS virus vaccine patent issues and to maximize the availability of products. “However, although we can suggest ideas for future collaboration, it seems unlikely that we will see the development of a vaccine that will provide a greater degree of protection against all strains of PRRSV than is provided by current vaccines.”
There have been some encouraging signs that some segments are beginning to work closer together, but more work is needed, particularly from swine practitioners, according to Dee.
He points to one example of where academia has begun to come closer together in efforts to find industry answers for the eventual eradication of PRRS. “One very good example of academic collaboration is the NC‑229 team. This 57‑member group, composed of researchers from 20 universities and representatives of numerous industrial partners, proposed a $4.4 million dollar project for work on basic and applied PRRS research that received funding from the USDA/NRI. Therefore – along with the work of Eric Neumann and the National Pork Board – for the first time large sums of research dollars are available for both basic and applied PRRSV research.”
This has resulted in “scientists from around the country working side‑by‑side with industry in a team effort to solve the problem, Dee says. “A call for proposals has been issued, project review has occurred and awards have been made to selected teams of investigators.”
Because of these new efforts, Dee believes that “the output from the research community will be staggering over the next four years.” At the same time, he adds, “with success comes a great deal of pressure, since these initiatives will be scrutinized very closely. If we engage in ‘turf wars,’ we will fail, looking extremely foolish in the process and will never get such an opportunity again.”
There are still a number of questions that remain unanswered, particularly in the areas of PRRSV genomics, immunology, eradication and biosecurity, according to Dee.
“To answer these questions correctly, I believe we need new models of research that incorporate controlled field settings and involve large populations of pigs in order to bridge the gap between university research settings and the real world.
“Our model at the University of Minnesota is our Swine Disease Eradication Center research farm. This is an actual farm, and thanks to the support of Genetiporc, hundreds of PRRSV‑
naive pigs are available to conduct infectious disease research in a commercial setting using large populations of pigs. The lack of these models in the early 1990s led to the formulation of a number of erroneous conclusions on how PRRSV would behave in the field.
“We cannot afford to make these types of mistakes anymore, and I challenge other universities to consider our research farm model as an option.”
“Finally, it is time to challenge the producers in our industry and raise their awareness to the fact that, like the lone scientist or practitioner, an individual farmer cannot win the PRRS war on their own. Producers must collaborate, think and act as a group, or team, (in) a region, and not as an individual farm or system, or even a company.
“This has not been the practice of the average pork producer over the years; however, the time is up for acting alone. Producers must cooperate to achieve the desired goal, just as universities and veterinary practices must do.”
Dee says that U.S. producers need to “take note that such collaborations are already underway in competing markets and the longer that we delay and do battle amongst each other, the faster we fall behind. Furthermore, new research from our group indicates that recently identified routes of regional spread of PRRSV – such as flies and transport – may be impossible to manage unless producers cooperate and organize regional projects.”
Dee concludes that “while the challenge of developing coordinated projects to enhance large‑scale control and eradication of PRRS is an enormous undertaking, the timing is perfect to make rapid progress toward answering necessary questions, conducting pilot projects and sharing the information across the industry.
“There is no need for wasting time keeping secrets. The NPB and the NC‑229 group are prepared for developing information to answer questions and solve problems, followed by communication of that information via extensive outreach efforts. The current AASV executive committee is very experienced with the issues presented by PRRS and is well positioned to lead. However, all will fail without unity
within our membership.”
Dee suggests that swine veterinarians evaluate their client base to identify producer groups that have the potential to work together to develop regional projects for PRRS eradication. In addition, he says, “hold meetings with neighboring practitioners and initiate conversations on how similar projects can be developed in surrounding areas. Support and assistance in these discussions and efforts can come from the AASV executive committee and district representatives, universities and industrial partners.”
PRRS: How did we get in this mess?
Even though we know a lot more about the PRRS virus since it first made headlines as the “Mystery Swine Disease” in the late 1980s, it continues as a costly and perplexing challenge for swine veterinarians and their clients.
In many ways, it has the same mysterious attributes as it had years ago. “PRRS virus is evolving genetically, escaping the pig's immune system, and foiling our attempts to control it,” says University of Minnesota swine veterinarian and PRRS researcher Scott Dee. “We can eradicate the disease from farms, yet re‑infection with a newly evolved PRRS virus is a frequent occurrence.”
And PRRS virus continues as “a very divisive entity, splintering the profession, causing veterinarians to work against each other on the farm, in the research lab and in the courtroom,” Dee says.
So, how did we get to this point?
In a recent presentation at the University of Minnesota Allen D. Leman Swine Conference, Dee pointed to the following as some of the factors that may have brought the pork industry to where it is today in the battle against PRRS:
The intense competition throughout the North American scientific community with regard to who would be the first to discover the etiology of PRRS and who would be first on the market with a vaccine. Commercial companies quickly teamed up with university researchers, and information became a closely held secret.
There have been unrealistic expectations about commercial vaccines that were initially viewed by practitioners as “golden bullets.” Comparisons between PRRS virus and pseudorabies virus were frequently made, and efficacy akin to PRV vaccines was expected.
The biology of the agent was unlike any other that veterinarians had ever dealt with before. Practitioners were not familiar with managing single‑stranded positive sense RNA viruses in pigs, particularly those that easily underwent genetic change, produced persistent infections and induced a prolonged viremia in the host.
The immune response that PRRSV elicited in the pig was very different than that seen in traditional pathogens, such as PRV and swine influenza virus. For the first time, veterinarians had to deal with concepts of intracellular pathogens and cell‑mediated immunity, as well as to try to make judgments on the protective immunity and the carrier status of animals without the luxury of commercially available diagnostic tests that could accurately detect and define these parameters.
A little more about Scott Dee
Swine veterinarian Scott Dee spent 12 years working as a practitioner in a swine-only veterinary practice in Morris, Minn., where he was first introduced to the devastating and frustrating porcine reproductive and respiratory syndrome virus in client herds.
For the past six years he has been with the University of Minnesota College of Veterinary Medicine, where much of his time has been spent conducting applied research on the transmission and elimination of PRRS virus under the auspices of the university’s Swine Disease Eradication Center.
Recently, he was elected vice president of the American Association of Swine Veterinarians and is a member of the AASV’s executive board.
Dee says that he chose to run for the office of AASV vice president because of the current situation regarding PRRS in North America. One of his primary goals is to work with other members of the AASV executive committee to take advantage of the current opportunity to impact the swine industry and the veterinary profession in a positive way in regards to PRRS eradication, he says.