Get Out Your Handkerchiefs

Already, mountains aren't as cool as they used to be, so insect-borne diseases are being reported at higher elevations in Latin America, Asia and Africa, including previously spared highland cities such as Nairobi. The mosquito that carries yellow fever and dengue fever, which once could not survive the cold above 3,300 feet, can now be found at 5,600 feet in Mexico. As dengue fever, yellow fever and malaria extend their range to higher elevations and higher latitudes, those diseases could appear in the developed world, too. The southern tier of Western and Eastern Europe, as well as the Southern United States, are most at risk, says Harvard's Epstein. Dengue fever has already popped up on the Mexican side of the U.S. border, a worrisome expansion of its current range. Say this for the climate contrarians who insist that a warmer world will be a better, more productive world: if they're referring to allergens and pathogens, they're dead right.

© 2007