“There is no doubt that environmentally related diseases will continue to pose problems in the future."
-Samuel Wilson
Bats make up for twenty-five percent of the mammal population, and White-Nose Syndrome (or WNS) has affected many bats throughout the country. This is a huge problem because WNS has a mortality rate near to 100%. In comparison, when the Bubonic Plague hit Europe in the 1300's and killed 2/3 of the population, the mortality rate was about seventy-two percent. White-Nose Syndrome has killed more than 5.7 million bats since it was discovered and has an infection rate of almost ninety percent among hibernating bats. WNS is currently a threat to six bat species: the Little Brown Bat, Northern Long-Eared Bat, Tricolored Bat, Small-Footed Bat, Indiana Bat, and Big Brown Bat. WNS is most dangerous to the Little Brown Bat, and is causing deaths mainly among the first three species. As noted in the below picture, WNS has spread to twenty-five US states and five Canadian provinces.
WNS starts growing in hibernating bats, which are at the perfect temperature for the disease to thrive. Pseudogymnoascus destructans (commonly shortened to Pd) is thought to have first been spread by tourists, and is a previously unknown disease, accounting for the high infection rate.
WNS causes fungus to grow on the bat's nose, causing itching, which awakens bats from their sleep, and disrupts hibernation. As a result, bats with the fungus are commonly seen flying during the winter or by day, which is extremely unusual behavior. When the bats engage in the flying, they use much of their precious energy, and cannot find food under the different conditions. Most bats that die of WNS are emaciated, and usually die from freezing, starving to death, or electrolyte loss. The symptoms of WNS are not limited to fungal growth; physiological imbalances are common as well. Bats with WNS have an altered metabolism that makes them use fat more quickly. This compounds on the problems of starvation that occur when the bats cannot find food. They also have high K+ levels, which can result in heart problems, and abnormal pH variations throughout the body. In addition, WNS causes damage to muscle tissues and blood vessels throughout the body
WNS can not be reliably treated due to the sheer number of bats infected, and is difficult to diagnose. A possible methods of diagnosis involves using an ultraviolet light, as the fungus from WNS can be clearly seen. There also are plans to take fur, blood, and fecal samples from bats that do not get WNS. This will hopefully show what genetic traits in bats make them more resistant to White-Nose Syndrome. (All bats in Western Europe have this resistance. As previously mentioned, WNS is devastating in North America because it was introduced here recently by a cave visitor.)
The ravaging effects of this disease have caused many previously flourishing bat species to have been brought to near extinction. On the optimistic side, research to cure WNS is advancing, and the disease has slowed since it started. Despite this, however, WNS is an active threat to bats, and continues to spread. See our post tab for updates on the research! We usually mention new developments.
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