Researchers use 'mini tanning beds' to treat white-nose syndrome in bats

Ultraviolet light treatment holds potential for battling the fungus that has killed millions of bats in North America.

UV light damages the fungus wiping out bat colonies across North America

Bats with white-nose syndrome hang in a cave. The deadly fungal disease has wiped out millions of bats across eastern Canada, but hasn't arrived in British Columbia yet. (Province of Alberta)

The Achilles' heel of the fungus that is killing millions of hibernating bats in North America could be as close as the local tanning salon.

Researchers in Madison, Wis. have found that the ultraviolet light worshipped by tanning enthusiasts also damages the fungus that causes white-nose syndrome.

White-nose syndrome has not been detected in bats in British Columbia, but officials are anxious about the spread of the disease, which was detected in neighbouring Washington state in 2016.

"What we found is UV light damages the DNA of this fungus," researcher Daniel Lindner, told On the Island's Gregor Craigie.

Lindner, a research plant pathologist with the U.S. Department of Agriculture in Madison, said UV light will damage any living organism. 

"This is what happens to us when we get sunburnt. Some of our skin cells die from UVB exposure," he said.

However, the study, published in January, found the fungus that causes white-nose syndrome is far more sensitive to UV exposure than anything else they tested, including bats and the microbiome of beneficial bacteria and fungi that live on the bats.

Mini tanning beds for bats 

With the identification of a potential Achilles' heel for the fungus, researchers devised a method to test UV light therapy on bats in the laboratory, so the results and the effect on the animals' health could be closely monitored.

"It's been referred to as mini tanning beds for bats," Lindner said. "That's very impractical in the field, obviously."

For field testing, the researchers hope to work with bat behaviour specialists and engineering experts to explore the possibility of installing a UV light-emitting tunnel or ring at the entrances to hibernacula — places where large numbers of bats hibernate. 

Lindner said the researchers found it takes only one second of UV exposure to damage the fungus.

A Kootenay National Park bat inventory documented 31 bats to help prepare for a possible invasion of white-nose syndrome, responsible for the deaths of millions of bats in eastern parts of North America. (Anne Forshner/Parks Canada)

"If we can hit them with even a fractional dose of it as they come and go, we hope that would be enough to knock back the fungus and make it so they could make it through the hibernation season," he said.

Lindner does not see UV light exposure as a magic bullet for stopping white-nose syndrome. 

"We've got such a large area with so many bats affected that we need very many tools in our tool box and we hope this is one tool that we can use to try and help prevent extinction," he said.

While white-nose syndrome has not been found yet in British Columbia, officials with the B.C. Community Bat Program are asking the public to report bats that are seen flying during the day, or are found dead during winter and early spring.

With files from Sterling Eyford and CBC Radio's On the Island.