Connecting the dots: the emerging science of conservation medicine links human and animal health with the environment

E: The Environmental Magazine, Nov-Dec, 2004 by Jim Motavalli

Should people be alarmed? Collinge's team hasn't found plague in Boulder's prairie dogs, though outbreaks have occurred elsewhere. The gun-happy hunters profiled in our July/August issue cite their carrying disease as one reason to pull the trigger, but Collinge says that prairie dogs "are not good plague carriers, and getting rid of them would not stop the spread of disease" (which could be taken up by other small animals). Further, she says that prairie dogs are "both keystone species and ecosystem engineers," providing food for eagles and, through their burrowing, increasing the capacity of the soil to hold water and vegetation.

Collinge's work represents an ideal cross-pollination of medical and veterinary sciences. Dr. Pokras of Tufts University says such cross-boundary collaboration is exactly what's needed. "We need to get the vets out of the barn," he says. "We need to change the mindset of all the groups--vets, physicians, scientists, conservation biologists, environmentalists-to be more broadminded and visionary."

Pokras notes that the veterinary profession has always been driven by economic factors, first working on horses in the 1700s, then moving on to cattle, sheep, pigs and other economically important species in the 1800s. Pets came later, as people acquired the means to keep non-work animals. Only very recently have vets worked for zoos and nonprofit groups. "Starting in the early 1980s," Pokras says, "a variety of veterinary schools--including Tufts and Cornell--took big steps to get involved in conservation projects. But vets still mostly talk to their peers, and publish in their own journals."

One hurdle, Pokras says, is recognizing the skills of other professions, and learning to speak the same language. As noted in Conservation Medicine, the first book on the subject, "The rich terminology of the biomedical and veterinary sciences poses particular difficulties for ecologists and conservation biologists." For instance, even the word "ecosystem" has different meanings for the different interest groups.

"We see the world in a different way," Pokras says. "It's like the five blind men and the elephant. But we need to overcome this problem because conservation on a global scale is so complex that no one group has the knowledge, skills and perspective to grasp it all and develop appropriate solutions."

Weapons of Mouse Destruction

An 1860 painting by Gustave Corbet entitled "Fox in the Snow" provides a dramatic example of the age-old predator-prey relationship. The fox catches the squirrel, just as it has for centuries. But what happens when humans inadvertently disturb the balance of nature by removing the predators? The role of predators in helping suppress disease is highlighted in work by Richard Ostfeld of the nonprofit Institute of Ecosystem Studies (which combines research and education work). Mammals are the most common reservoirs of zoonotic disease, and rodents play the leading role, implicated in the spread of plague, Lyme disease, hantavirus and Rocky Mountain spotted fever.