TEXAS livestock authorities will test their disease "response-ability" in early November, when a simulated outbreak of foot-and-mouth disease strikes south Texas, as part of an international test exercise. Foot-and-mouth is a highly contagious viral disease that does not affect humans, but causes severe blistering and open lesions in the mouth and on the hooves and teats of susceptible animals. Animals stricken by this foreign animal disease become lame, lose weight, stop producing milk and become debilitated. Young animals may die.

"This is an opportunity to test our planned respond to a livestock disaster in Texas, as we'll be the U.S.' site for the initial disease outbreak for this exercise. We want to see how quickly and efficiently we can tackle an outbreak." said Dr. Walter Riggs, area epidemiologist in Texas for the U.S. Department of Agriculture's Veterinary Services. He and Dr. Ken Waldrup, field epidemiologist for the Texas Animal Health Commission (TAHC), the state's livestock health regulatory agency, are members of the international planning team, which has included livestock authorities from the U.S., Canada and Mexico.

"Even one case of foot-and-mouth disease could stop our ability to trade livestock and livestock products across state lines and internationally," said Dr. Riggs. "Because it is so contagious, and we have so much global trade and travel, this fast-moving disease always poses a threat to North America. It is also an excellent disease for an exercise scenario, as it can affect a wide variety of livestock and moves quickly through a population."

DR. RIGGS said the simulated outbreak will demonstrate how long disease can go unnoticed, and how quickly the foot-and-mouth virus can spread among susceptible animals, which include cattle, sheep, goats, pigs, deer and all other species with cloven or split hooves. No animals will be sacrificed in the exercise.

However, in an actual outbreak, affected animals would be destroyed to stop the spread of disease. Carcasses would be burned or buried, and premises would be disinfected. Strict livestock movement restrictions, biosecurity practices and the administration of vaccine are control measures also employed to contain an outbreak.

By simulating a foreign animal disease outbreak, said Dr. Riggs, the joint TAHC and USDA "Texas Emergency Response Team" or TERT, can practice working within the structure of Texas' Division of Emergency Management, headed up by the Texas Department of Public Safety (DPS). Under this statewide system, TERT can benefit from the equipment, manpower and technical assistance from agencies such as the Texas Department of Transportation, Texas Parks and Wildlife Department, Texas Department of Health and local disaster emergency management organizations. Actual outbreaks of foot-and-mouth disease in recent months have resulted in thousands of animals being destroyed to stop the spread of the disease.

In Greece more than 7,000 affected head were depopulated, while more than 14,000 head were destroyed in Paraguay, Brazil, Argentina, Colombia, and Uruguay. In addition to the direct losses of livestock, affected countries suffer severe trade restrictions until they are proven to be free of disease. Restrictions can apply not only to susceptible live animals, but also frozen meats, processed products, such as hams, and leather goods.

Since l995, Uruguay, for example, was considered free of foot-and-mouth disease and was the world's 12th largest exporter of beef in 1998. On Oct. 27, 2000, Uruguay reported laboratory confirmation of a foot-and-mouth disease outbreak and suspended beef exports.

Likewise, the United States has put on hold any imports of animal products from the country. Restrictions will stay in place until Uruguay proves it is again free of the disease, which could take years.

"The TAHC does not have adequate resources to handle an outbreak in which thousands of animals would have to be vaccinated or destroyed," said Dr. Linda Logan, Texas' state veterinarian and executive director of the TAHC, which has only about 225 staff, including veterinarians, animal health inspectors, laboratory technicians and office support personnel.

"It is essential that private practitioners, livestock associations, producers and other agencies work together. In a situation involving foot-and-mouth disease, deer and feral swine are also susceptible, which only magnifies the potential animal damage and workload." she said.

"For more than two years, the TERT team has been learning to work with the Texas Division of Emergency Management," she said. "After the devastating floods of l998, we realized how effective interagency cooperation could be when producers called us to help locate or identify thousands of stray livestock.

"We also were asked to help bury or move livestock carcasses, and we had to establish contacts quickly with other agencies, as we did not have the necessary equipment. To be prepared, we had to be part of a larger team."

Dr. Riggs said that, on an international level, the exercise will test communications, coordination and decision-making among Canadian, Mexican and U.S. livestock health authorities. The countries will have to determine when and where extremely limited supplies of foot-and-mouth vaccine will be distributed and used.