LARAMIE -- Forget, for a moment, that the Greater Yellowstone Area is a complex region where people struggle for a living, retire and vacation. Forget that it is a giant ecosystem shared by elk, bison, bear and cattle. Forget that politics are thick in the air and that change seems synonymous with controversy.

For now, think of the Greater Yellowstone Area as a crucible in a science project.

Scores of top scientists from around the world gathered at the University of Wyoming in Laramie this past week to focus narrowly on only the science -- not the politics -- of one question: What needs to be done in order to better vaccinate elk and bison against the disease brucellosis?

"There's more brainpower focused on these critical questions than has ever been assembled for the Greater Yellowstone Area," said Glenn Plumb, supervisory wildlife biologist for Yellowstone National Park.

"This connects the land management agencies and regulatory agencies with the network of people doing (research and development) in a way that hasn't happened in the past," Plumb said.

Brucellosis is a bacterial disease that can cause a cow to abort her first calf. It has been known to spread from feedground elk to cattle and may be able to spread from wild bison to cattle, although there has never been a documented case of such an infection. It can infect people, but rarely does in the U.S.While the disease is fairly common in bison and feedground elk in the region, Montana and Idaho are classified Brucellosis Free for purposes of exporting cattle.

Wyoming shared that classification until three brucellosis-infected cattle herds were detected in 2003 and 2004. Wyoming producers must now conduct additional tests before shipping many cattle out of state, raising the cost of raising beef here.

The United States Animal Health Association brought the scientists to Laramie and asked them to come up with research priorities aimed at creating better vaccines, vaccine delivery systems and diagnostic tests.

The scientists included experts on rabies and a host of other diseases -- such as West Nile, mad cow and chronic wasting -- that, like brucellosis, may move between wildlife and livestock. They discussed what is known, and what needs to be better understood, about a disease that has been known to plagued people and livestock since the 1770s.

"Our hope is this will be a template for addressing other wildlife issues," said Rick Willer, USAHA president. "Brucellosis is an easy disease. It is in a difficult landscape. I guarantee you there will be more difficult diseases down the road."

Politics of vaccination

Vaccinating wild elk and bison without handling every animal has been a major challenge in the Rocky Mountain region's battle with brucellosis.

Experiments with existing vaccines have been under way with captured bison in Yellowstone and feedground elk in Wyoming, but existing vaccines don't protect either species very well. Existing diagnostic tests make it hard to tell vaccinated animals from infected animals.

These shortcomings have frustrated ranchers and wildlife managers. And while coffee shop talk in brucellosis country often turns to the hope for a "silver bullet" solution, federal disease experts cautioned that no such thing would emerge from the Laramie conference.
"This is not intended to be a workshop that ends up saying the perfect vaccine will fix this," said Valerie Ragan with the Animal and Plant Health Inspection Agency. "Vaccine is one possible tool that can be used, not the only tool."

Still, vaccines that might break the cycle of disease transmission in wildlife could help advance some of the politically thornier land and wildlife management issues, including the possibility of reducing the dependence of elk in Western Wyoming on being fed in the winter.
"If we want to merge or clean up a feedground some day, if you're going to have local support for dispersing these animals a little bit more, it's going to be easier with animals that are vaccinated than animals that are not," said Frank Galey, dean of the University of
Wyoming's school of agriculture.

Old and new vaccines

The best hope for a better brucellosis vaccine may lie in improving the current one, vaccine developers at the conference agreed.

A vaccine known as RB51 has been the standard U.S. vaccine for cattle since 1996. RB51 is used with less success in bison and is not effective at all in elk.

The vaccine experts gathered here agreed that new technology may allow totally new wildlife vaccines to be developed, but that process could take decades.

For more near-term results, the group emphasized continuing recent work to enhance RB51.

"We may have the (best) vaccine in front of us," said Phil Elzer, a vaccine researcher from Louisiana State University. "New approaches which have been tested seem to be very effective in improving protection."

Gerhardt Schurig, dean of the Virginia-Maryland Regional College of Veterinary Medicine, developed RB51. He and other researchers have found that new RB51-plus versions are significantly more effective in test models.

Tests in mice and cattle of one of those versions, RB51-DOD-wboA, indicate this vaccine completely protects an animal from brucellosis infection, Elzer and Schurig said. It is not clear if the RB51-plus vaccines will work on bison or elk.

Schurig said large-scale trials using cattle, bison and elk are needed to prove the safety and effectiveness of the new vaccines. An optimistic timeline could see those vaccines available for use in five years, he said.

Similar work using other approaches and strains of brucella is being done at the Texas A&M University, and still more work is being done on a Soviet-era vaccine, known as Strain 82. Lead researchers working with all of these vaccines were in Laramie for the conference.

Many ranchers have a long-standing affection for Strain 19, the vaccine that was used until 1996. RB51 replaced Strain 19 because it was often not possible to tell animals vaccinated with Strain 19 apart from animals infected with brucella. RB51 eliminated that concern.
Also, Strain 19 could infect veterinarians and others with brucellosis if they were accidentally stuck with a vaccine needle. RB51 poses much less of a risk.

Schurig said it took more than 10 years for RB51 to be approved for use with cattle in Greater Yellowstone. Because so many experiments have been done on RB51, it might be easier for the enhanced vaccines to clear bureaucratic hurdles than it would be for a brand new vaccine.

The Laramie group agreed that other research should consider new vaccines and new vaccine technologies such as DNA vaccines.
"There area several other candidates on the horizon that could be stronger than RB51," said Garry Adams of Texas A&M. "I think it's justified to use RB51 until we have something better."
Biosecurity issues

After three days of focus on science, politics still rose to the top when talk shifted to what it would take to turn ideas into action.
Homeland Security restrictions and funding emerged as the two biggest barriers to building and delivering better vaccines.
Homeland Security restrictions make it hard to get brucellosis samples needed to test the effectiveness of vaccines and restrict where that work can be done.

LeeAnn Thomas, who oversees access to restricted pathogens for the U.S. Department of Agriculture, said because RB51 is already excluded from those restrictions, at least one of the RB51-plus vaccines would also be excluded.

"There is another advantage of using an organism for which you already have a lot of data," she said.

Brucellosis is covered under Homeland Security rules because it might be developed as a bioweapon.

This inclusion of brucella as a "select agent" under the Bioterror Act of 2002 is among the reasons it takes so long to license new vaccines, researchers said. The classification prohibits working with restricted brucella bacteria outdoors, but conducting required large-scale trials with big wild animals such as elk and bison is almost impossible to do indoors.

Thomas said efforts are under way to come up with a checklist of conditions that would allow larger outdoor biocontainment facilities to be built.

Still, she warned, it is against the letter and spirit of the law.

"You are doing exactly what the Bioterror Act does not want you to do: Putting a known bioterror agent into the environment," she said.

A shortage of research funding is the other major source of delay in vaccine development, researchers said.

"This is not going to be cheap. We have to find the funding," said USAHA president Willer. "We need to convince Congress that this is not just for brucellosis but for other diseases that impact people, wildlife and domestic animals. This is a bigger issue than just brucellosis in the Greater Yellowstone Area,"

The Laramie workshop, formally called the United States Animal Health Association Brucellosis Vaccine and Diagnosis Workshop, ran Aug. 16-18.

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