Bats with white-nose syndrome may have a white fungus on their noses and often on other hairless parts of their bodies like the wings. We do not know if the fungus is causing the deaths or is symptomatic of whatever is causing the deaths. The fungus isn't always visible to the naked eye -- and usually is not seen on bats found flying or dead outside of their hibernacula or at their summer roosts.
Researchers have identified several different fungal species from bats with and without external signs of fungus, according to the U.S. Geological Survey's Wildlife Health Center in Madison, Wis.
An initial article about the fungus, which is particularly suited to cold temperatures, Bat White-Nose Syndrome: An Emerging Fungal Pathogen? (PDF 1.17MB) was published in the Oct. 30, 2008, ScienceExpress and in the Jan. 9, 2009, Science Magazine.
This fungus, formerly known as Geomyces sp. is now known as Geomyces destructans. This is the characteristic white fungus that gives white-nose syndrome its name. Geomyces destructans sp. nov. associated with bat white-nose syndrome (PDF 721KB) by A. Gargas, M.T. Trest, M.Christensen, T.J. Volk and D.S. Blehert, published in Mycotaxon, April-June 2009.
Procedures for microscopic tissue study to identify WNS are detailed in Histopathologic criteria to confirm white-nose syndrome in bats (PDF 3.15MB) by Carol Uphoff Meteyer, Elizabeth L. Buckles, David S. Blehert, Alan C. Hicks, D. Earl Green, Valerie Shearn-Bochsler, Nancy J. Thomas, Andrea Gargas and Melissa J. Behr, published in Journal of Veterinary Diagnostic Investigation, 21:411-414 (July 1, 2009).
Human health implications are not known; there is no information indicating that people or other animals have been affected after exposure to the white fungus.