Consider two pandemics: the white-nose syndrome now devastating North American bats and the Black Death that killed a third or more of Europeans in the 14th century. Lethality aside, they may not seem to have much in common. But recent studies suggest they both offer important lessons about understanding that the deadliness of disease organisms is very much a product of the circumstances in which they appear.
Two weeks ago in Nature, a multi-institutional team of U.S. Geological Survey scientists presented conclusive evidence the parasitic fungus that lends white-nose syndrome its name is indeed the cause of the mysterious bat epidemic. The illness came to light in New York in 2006, when cave explorers started finding thousands of little brown bats (and later, other species) dead together in the caves where they spent the winter months, their bodies covered with a white fungus, Geomyces destructans. It has since spread throughout the northeastern U.S., where bat populations have declined on average by 73 percent—which may make it one of the most rapid declines in wildlife populations ever observed. Worse, white-nose syndrome is still on the move, with documented cases in four Canadian provinces and states as far south and west as Tennessee, Missouri, and Oklahoma.