**Abstract**

White-nose Syndrome (WNS) is an emergent mycosis in North America that is caused by a severe cutaneous infection with the fungus *Pseudogymnoascus destructans* (*Pd*) during hibernation. *Pseudogymnoascus destructans* (*Pd*) was first observed in North America at a single site during the winter of 2006–2007 and has since spread to 39 U.S. States and 7 Canadian provinces. This fungus was introduced to North America from Europe, where it is endemic. WNS has thus far been observed to occur only in hibernating bats and has caused the populations of 4 North American bat species to decline by more than 84% within 7 years. Field studies have revealed that 4 other North American bat species are not afflicted with WNS when hibernating in areas where *Pd* occurs. The physiological and biochemical adaptations that permit some bat species to resist *Pd* infections are starting to be elucidated but are still poorly understood. A total of 47 different bat species are found in North America, about half of which hibernate during the winter. The potential future effects of WNS on 13 of these hibernating bat species remains to be determined.

**Keywords:** mycosis, hibernation, immunity, *Pseudogymnoascus destructans*, lipids
