FROM THE COLLECTIONS
> Cover Story
Snakes on a Plane
(continued from previous page)
| Page 2 |
SOME LIKE IT HOT
Conservation medicine emerged at Brown with the arrival of Katherine Smith, a young assistant research professor in the Department of Ecology and Evolutionary Biology. She and her husband, ecologist Dov Sax, were hired in 2007. Though Sax’s expertise is in species extinction, invasions, and climate change, they’ve published a number of papers together on disease and environmental change.
“Conservation medicine is really a brand-new field,” Smith says. “We’re still asking very basic questions about how environments change and influ influence disease. We’re able to study these interactions now because we finally have large global data sets of diseases, where they occur, and why. Likewise, we have new laboratory technologies that allow us to identify pathogens that we couldn’t 20 to 30 years ago. It’s a frontier science in that way.”
“The phrase was coined in the ’80s,” says Peter Daszak, president of Wildlife Trust, the 35-year-old international conservation organization. As research on environmental damage progressed, scientists realized it was “no good just to look at human behavior and say ‘we’re going to fix it.’ The diseases are coming from wildlife and the changes in their environment … There’s been a groundswell toward this holistic approach.”
The number of emerging infectious diseases increased markedly in the 1980s and 1990s. Smith explains, “[T]he majority of these came from animals. This is the real question for conservation medicine: How are we altering and changing the environment in ways that we are setting ourselves up to get disease from animals?”
Human impact on the environment is well studied. Population size has grown, taxing natural resources. Deforestation and urbanization have led to humans encroaching on habitats that we’ve never been in before. “Hot zones” have developed throughout Asia and Africa, where climate change, unregulated development, and loss of natural habitat have given rise to infectious disease. We’ve even seen it happen in the U.S., where every summer brings warnings against mosquito-borne West Nile Virus and tick-borne Lyme disease— zoonotic diseases transmitted by para-sites that feed on both animals and humans.
“Pathogens are opportunistic,” Smith says. “[H]umans are coming into frequent contact with a diversity of animals, creating opportunity for pathogen spillover from them to us.”
Climate change is making it possible for some animals—and their parasites— to live in new geographic areas, and that, too, has an impact on human health and emerging infectious disease.A report by the Center for Health and the Global Environment at Harvard, called Climate Change Futures: Health, Ecological and Economic Dimensions, examined the spectrum of physical and biological risks humans face from an unstable climate. Its conclusions? Warming favors the spread of disease; extreme weather events create conditions conducive to disease outbreaks; and climate change and infectious diseases threaten wildlife, livestock, agriculture, forests, and marine life. In an appearance at Brown in March, the report’s co-author, Dr. Paul Epstein, MPH, said, “We underestimated the rate of climate change, and we’ve underestimated biological response.”
Alpert Medical School