At this time, Pseudogymnoascus destructans is confirmed to cause the white-nose syndrome (WNS). Specifically, it is confirmation of the lesions caused by the fungus that clinically confirms the presence of the disease in the animal. A recent technique to determine a new clinical sign of bats infected with WNS uses ultraviolet (UV) light to transilluminate wing membranes of bats. Bats infected with WNS have diagnostic lesions where the associated fungus P. destructans invades the wing membrane, and when exposed to the UV light the fungus in these lesions exhibits orange coloring. The technique allows for non-lethal diagnosis and the area of wing membrane that is affected with the white-nose syndrome can be quantified through photo documentation.