DANBURY — Two local researchers are trying to find a quicker and cheaper way to detect a fungus that has killed millions of bats, and in some cases, wiped out entire cave populations in North America.
More than 6 million bats have died since white nose syndrome appeared in the U.S. about a decade ago.
In Connecticut, the little brown bat, the tri-colored bat and the northern long-eared bat have all lost significant numbers.
The disease is caused by a fungus, Pseudogymnoascus destructans, which infects hibernating bats’ muzzles, ears, and wings, giving the disease its name. There are two main techniques used to find this fungus, but one isn’t very effective and the other is too expensive for most to use because it requires a machine that costs a minimum of $10,000.
“We’re trying to make it cheaper and easier to detect,” said Hannah Reynolds, an assistant biology professor at Western Connecticut State University, who has spent the summer working with Jasmine Grey, a junior at the university, to develop a new method.
The goal is to accomplish the same results without the machine. Ideally a person will be able to swab a bat or cave, test the sample in about 35 minutes and see if a gene specific for that fungus is present, thus showing the fungus itself is there.
“The more we have data on where white nose syndrome is, the more we can work to solve the problem and save the bats,” Grey said.
The test they’re using was developed for a rapid response to human pathogens, such as malaria. It has since been used in agriculture to see if a pest is present in a field.
Reynolds was inspired by the success at the plant level to try it with wildlife.
They said it was important to save the bats because of their role in the ecosystem. The bats also eat insects that can damage crops or spread illness. Bats also only have one pup a breeding season, which makes it harder for them to recover from the population loss.
“They don’t reproduce as quickly as other small mammals do,“ Reynolds said.
White nose syndrome was first discovered in 2006 in New York. It’s since spread to 33 states in the U.S. and seven Canadian provinces. In some areas 90 to 100 percent of the bats have died. It was confirmed in Connecticut in the winter of 2007/2008 with sightings in the northwestern part of the state.
It’s believed the fungus is largely spread by human activity. Several caves have closed to the public, including Tory’s Cave in New Milford to prevent the spread of the fungus by being tracked in on people’s clothes or boots.
There are three distinct genes that separate this fungus from the other similar fungus.
Reynolds and Grey are honing in on one specific gene to see if the fungus that causes white nose syndrome is present.
This testing method, called loop amplification mediated PCR, or LAMP, replicates specific pieces of DNA to help see if a gene is present. This is done by adding samples of DNA into prepared solutions of primers and then heating at a certain temperature. The primers attach to a certain gene and amplify it. The trick is to amplify just that gene without amplifying other genes that are present in the similar fungi.
Reynolds said finding what isolates that one gene is the hardest part, especially because the fungi are so similar.
Grey has determined the most successful ratio of primers and is now playing with the heat to make it more specific. The machine allows each well to have a separate temperature so they can test 12 different temperatures at once.
The duo is using samples of the fungus that causes the disease, as well as similar fungi, to see which chemical solution and temperature best identifies that gene. They are working with 32 samples, mostly from the North East and a mix of the fungus found on bats and cave walls.
”Most of them are non-targets,” Grey said. ”It’s more important to make sure they don’t amplify so we have more them.”
The summer work on the detection method ended Thursday but the duo will resume when school starts again in the fall. Grey will continue to optimize the technique with the hopes of them then training conservationists and land managers at parks to test.
”I feel really good about the progress we’ve made,” Reynolds said. “Now we can hone in and make it as specific as possible.”