White-nose Syndrome FAQs

bat with white nose syndrome

NPS photo/von Linden

White-nose syndrome (WNS) has been spreading across North America from near Albany, N.Y. since the winter of 2006-2007. This fungal disease has killed millions of bats, devastating 90-100% of some bat populations. The disease is complex - learn more about it by browing the FAQs below. The WNS national team has a website, too, where you can learn more: whitenosesyndrome.org.
WNS is a fungal disease that affects cave-dwelling, insect-eating bats. It's killed millions of bats in the US, up to 99% of some populations. Scientists first discovered WNS in NY in the witner of 2006-2007. They have evidence that the causal fungus is from Europe, but the bats there do not suffer the same mortality.
In addition to the white muzzles and wings, bats acting strangely could indicate WNS. This includes bats flying outside during the day in freezing temperatures. Another sign is bats clustering around entrances of hibernacula (places where they hibernate) or dead or dying bats on the ground in winter.
A fungus called Pseudogymnoascus destructans causes WNS. It is often displayed as a powdery white substance around infected bats’ muzzles and wings.
Researchers have learned WNS is spread from bat to bat when they touch and also from cave surfaces to bats. Scientists also think that humans have the potential to carry the fungus from cave to cave, increasing the rate of spread.
Many things! Park personnel are busy monitoring bats, educating visitors about WNS, and protecting bat habitats. Our scientists work with researchers from other agencies to learn more about WNS and its effects on bats. Management has made decisions to close certain caves to protect hibernacula and maternity roosts. Also, park visitors are asked to answer a few simple questions and disinfect their gear and/or footwear as needed before entering caves.
Current evidence indicates that WNS is not transmissible from bats to humans. Studies have shown that the fungus grows only at cold temperatures (41-68 degrees F) that are much lower than that of the human body. Also, no human infections have ever been documented after exposure to WNS-infected bats or caves.

Although WNS does not cause illness in humans, a small percentage of bats can be infected with other dangerous diseases, such as rabies. Bats infected with either WNS or rabies may exhibit unusual behavior (e.g. erratic flying), which increases the risk for bat-human contact and exposure. Additionally, declines in bat populations can impact human health indirectly since humans depend on bats for important ecosystem services such as controlling pest insects.
Do not touch the bat, but be sure to tell a Park Ranger so it can be tested for diseases. These bats will be removed to protect both humans and other bats.
Decontamination simply means disinfecting gear or shoes that have been in another cave. It is important to leave these items behind or clean them to reduce the risk of humans spreading the WNS-causing fungus from cave to cave. Rangers will guide you through a simple process of cleaning any hard, non-porous surfaces that have been in other caves. Other items may need to be left behind.
Before you enter a cave, your park ranger will ask you three simple questions:
1. Have you been in a cave before?
2. Are you wearing the same clothes or shoes?
3. Are you using the same gear?

If you answered yes to question 2 or 3, then a ranger will be happy to show you the simple process for sanitizing your gear or determining if it simply needs to be left behind. After you leave a cave in a WNS-positive area, it's important to take a couple of minutes to sanitize your gear to avoid carrying the fungus into other caves. Additionally, you should not use this gear in caves where WNS is not present.
Yes! It is important that humans do not accidentally help spread WNS. Scientists are still learning about the disease and how it’s spread, but properly cleaning shoes and gear that’s been near the fungus is a quick and easy way to keep humans from moving the fungus from one cave or region to another. However, because decontamination doesn’t get rid of all risk of WNS transmission, gear used in WNS-affected sites cannot be used in WNS-free locations.
Millions of bats have died, but it's difficult for scientists to accurately estimate the number of bats we've lost. In some hibernacula, 90-100% of the bat populations have been destroyed.
Bats are important native species. The cave-dwelling, insectivorous bats most at risk for WNS are quite busy when they’re out at night. They help control insect populations by eating large amounts of mosquitos and moths every night. Additionally, bats serve as prey for other animals.
WNS mainly affects hibernating, cave-dwelling bats, so particular species are more at risk than others.
Throughout our national parks, more than 50 species of bats live in trees, in old buildings, in caves, in old mines. Some bats migrate during the winter, while some hibernate in caves or mines. Many parks have habitats that support different kinds of bats.
No. Bats actually live 10-15 years naturally, and they usually have only one pup per year. With that slow rate of reproduction, it is important to keep their hibernacula and maternity roosts undisturbed and free of the fungus.

Last updated: September 17, 2018