How to control a 'virtual outbreak'

For several months, it dominated evening news coverage and dinner conversation. People couldn't go to the grocery store without thinking about it, and canceled their trips to Europe because of it.

The recent outbreak of foot-and-mouth disease in Great Britain has, without a doubt, captured the American public's attention in ways that few livestock diseases have. Add it to the frenzy over bovine spongiform encephalopathy, and a full-fledged "virtual outbreak" begins.

"What happened in the U.S. was an extraordinary event," said Dr. Simon Kenyon, extension veterinarian and associate professor of population health at the Purdue University School of Veterinary Medicine. "There was a sense of apprehension and impending doom in response to this."

Dr. Kenyon served as a moderator for the recent Summit on FMD, presented by Watt Publishing and Vance Food Systems Group and held June 4 in Chicago. Close to 150 government officials, veterinarians, feed industry representatives, and foreign experts on FMD, and others, gathered to discuss the virtual outbreak, as well as ways to prevent a real one.

"We need to look very carefully at what the real risk of the admission of the disease in the United States is, and try to get some perspective, because I think that's what's been lost," Dr. Kenyon said.

Dr. Chester A. Gipson, associate deputy administrator of USDA-APHIS Veterinary Services, said all the public and media attention on FMD has fostered a perception of elevated risk. 

"From the standpoint of the USDA, there was kind of a heightened awareness that we import things from all over the world, but no increased risk," Dr. Gipson said. Because of BSE, European imports were already tightly restricted when the FMD outbreak began, he said.

"I think we've identified the major pathways through which the disease enters the country, and we've put a lot of emphasis on those," he said.

Dr. Linda Logan, who as Texas state veterinarian is charged with protecting the state's more than 36 million head of livestock as well as wildlife, said she thinks the public has been focused on the wrong pathways. Footbaths at airports—which Dr. Gipson said some travelers were actually requesting—are not as important as controlling the imports of animal products, she said.

"What is the real risk—is it your boots, or the sausage in your pocket?" she said. "I would contend that illegal meat products are the major risks. Swill feeding is a major risk.

To reduce the risk, Texas is banning swill feeding—or the feeding of liquefied waste, which might include food scraps or remains of other animals—for the first time ever, Dr. Logan said. Other speakers—including Simon Barteling, MSc, an adviser on animal disease to the Dutch and South African governments and former head of the international reference center on FMD—said they also believe swill feeding must be eliminated if the disease is to be controlled.

Speakers from industry groups, including the National Cattlemen's Beef Association and the National Pork Producers Council, highlighted measures producers must take to ward off FMD. For example, Brian Bursiek, treasurer of the American Feed Industry Association, discussed how his organization would inform feed distributors about disinfecting delivery trucks and other safety measures in the event of an outbreak.

If preventive measures taken by industry and the government were to fail and the disease arrived on U.S. shores, there are several methods that could be taken to eradicate it. Several speakers offered perspectives on stamping-out, vaccination, and combination approaches.

Dr. Barteling, a self-proclaimed "vaccine guy," touted the advantages of the ring vaccination method, where veterinarians begin vaccinating a circle of threatened but not yet infected animals a certain distance away from the infected farm and work their way in toward the outbreak farm. It's inexpensive, can be carried out by relatively few staff members, and reduces the drastic loss of animal life and mental anguish of owners, he said. Even though vaccinated animals would have to be destroyed once the disease were eradicated to return a country to an FMD-free trading zone, the pyres of burning carcasses witnessed in the United Kingdom would be avoided.

"Each case represents a human tragedy, and that's something to keep in mind ... the damages to lives and to rural communities—the social damage—has to be weighed by our profession as well, I think," he said.

The United States has a decision tree that would become effective in the course of an outbreak, determining when and where to use vaccines, said the USDA's Dr. Gipson. However, APHIS policy states that vaccination is not a first step against the disease, but a supplementary measure to other methods of eradication.

No matter what methods are used to prevent and control the disease, panelists agreed that public perception and public information are of the utmost importance. Confidence in government, veterinarians, and the food supply must be maintained to avoid devastating economic loss.

"I cannot say enough about the importance of transparency," Dr. Gipson said. "People will get concerned about what they don't know more than what they do know."