Diseases have always come out of the woods and wildlife and found their way into human populations — the plague and malaria are two examples. But emerging diseases have quadrupled in the last half-century, experts say, largely because of increasing human encroachment into habitat, especially in disease “hot spots” around the globe, mostly in tropical regions. And with modern air travel and a robust market in wildlife trafficking, the potential for a serious outbreak in large population centers is enormous.
The key to forecasting and preventing the next pandemic, experts say, is understanding what they call the “protective effects” of nature intact. In the Amazon, for example, one study showed an increase in deforestation by some 4 percent increased the incidence of malaria by nearly 50 percent, because mosquitoes, which transmit the disease, thrive in the right mix of sunlight and water in recently deforested areas. Developing the forest in the wrong way can be like opening Pandora’s box. These are the kinds of connections the new teams are unraveling.