Reducing a mammal’s temperature in the laboratory to find out whether lower body temperatures lead to fungal disease is difficult because messing with body temperature can affect many other biological processes. But hibernating bats may provide a clue that Casadevall is onto something, says David Blehert, a microbiologist with the U.S. Geological Survey’s National Wildlife Health Center in Madison, Wis.
Blehert studies white-nose syndrome, a fungal disease that is killing bats in large numbers in the eastern United States. A fungus called Geomyces destructans infects bats while they are hibernating—a time when body temperatures drop from 40° C to about 7° . “They’re not warm-blooded when they get infected,” Blehert says. When bats are up and around and at their normal body temperature, they seem impervious to the infection, he says.
In a report published November 11 in BMC Biology, Blehert and others described how the fungus, which erodes and replaces the bat’s skin, damages wings and leads to death. Casadevall’s idea has “become important in our thinking about this disease,” Blehert says.
The idea of a link between fungal disease and body temperature is not controversial among scientists, Blehert says. “It’s very logical.”