BioQuakes

AP Biology class blog for discussing current research in Biology

Tag: Bats

White Nose Syndrome

White Nose Bats

What causes the disease?

Exposure to UV light is the cause of a devastating disease found in North America. According to USDA Forest Service, the disease”can only infect bats during hibernation because it has a strict temperature growth range of about 39-68 degrees Fahrenheit”. Bats are very sensitive to the ultra-violet light which causes the P. destructans fungal pathogen(any disease-producing agent) to trigger the disease.

A bat affected by White Nose Syndrome.

When is a bat most at risk?

During hibernation, bats face a high risk of the white nose syndrome. WNS officials claim that the bats act strangely during cold winter months, including flying outside in the day and clustering near the entrances of hibernacula (winter quarters for a hibernating animal).

Effects of WNS

Bats have been found sick and dying in unprecedented numbers in and around caves and mines. WNS has killed more than 5.7 million bats in eastern North America.

This bat is in hibernation and at risk of WNS.

What is being done?

A research team has identified in the pathogen an enzyme that repairs DNA causing the team to expose the fungi to DNA damaging agents, including different wavelengths and intensities of UV light. Consequently, they found that a low dose exposure of UV-C light resulted in about 15 percent survival of P. destructans.

New Research Uncovers Bat Super Immunity

Recent research has discovered a unique ability in bats to carry diseases but remain symptom free.  This ‘super immunity’, as it has been called by researchers, is currently a mystery to scientists but could one day provide methods for achieving super immunity in humans.

Bats are know to carry many diseases that are deadly to humans like the Ebola virus, Hendra virus, and MERS (Middle Eastern Respiratory Syndrome).  For some reason, their immune system allows them to not get sick or show any signs of the disease.  Research published in the journal Proceedings of the National Academy of Sciences might allow us to better understand why this strange phenomenon occurs in bats.  These researchers looked deep into the immune system of bats, especially into the interferons.  An interferon is defined as “a protein released by animal cells, usually in response to the entry of a virus, that has the property of inhibiting virus replication.”  According to the research, bats only have three interferons, which is less than a quarter of the number of interferons possessed by humans.  “This is surprising given bats have this unique ability to control viral infections that are lethal in people and yet they can do this with a lower number of interferons” says Dr. Michelle Baker, an immunologist at CSIRO’s Australian Animal Health Laboratory. Researchers also found another notable difference in how bat immune systems work as a whole.  While most mammals only activate their immune systems when they are infected by something, bats seem to always have active immune systems. Having the immune system active at all times can be dangerous in most animals because it can be toxic to cells, but bats seem to be perfectly fine.

Myotis yumanensis (Yuma myotis)

Image Source: http://bit.ly/1T4Qn0r

While information on bat super immunity may be limited at the moment, future research could prevent outbreaks like the Ebola virus in West Africa.  Dr. Baker describes the potential of this research well by saying, “If we can redirect other species’ immune responses to behave in a similar manner to that of bats, then the high death rate associated with diseases, such as Ebola, could be a thing of the past.”

Article Source: http://www.biologynews.net/archives/2016/02/22/bat_super_immunity_could_help_protect_people.html

Further reading: http://mashable.com/2016/02/24/bat-super-immunity/#_6DA21uIkiqU

 

White-Nose Syndrome Threatening Brown Bat Species

In 2006, hibernating bats in upstate New York were identified with white-nose syndrome , a disease that produces a white fungal growth around the wings, mouth and nose of bats. The disease is a huge problem for North American bats, with it killing at least 6 million brown bats and the disease now spreading from New York to Mississippi and Canada. The disease may even threaten the entire bat species and disrupt the ecosystem. Scientific researchers have been studying WNS for over a decade and only recently have they developed a reason for its lethal effect on the North American bat population.

Researchers from the US Geological Survey and the University of Wisconsin learned that the fungus Pseudogymnoascus destructans kills brown bats by “increasing the amount of energy they use during hibernation”. When bats are hibernating during the winter, they must carefully save up their energy to survive without eating until the winter ends. The fungus drains bats of their energy and forces them to wake early and either starve or freeze to death. The study done by USGS measured how much fat was burned and at what rate during hibernation between non-infected and infected bats. Dr. Michelle Verant, a USGS National Wildlife Health Center scientist, found that bats infected with WNS used twice as much energy as the healthy bats during hibernation and had “potentially life-threatening physiologic imbalances that could inhibit normal body functions”.

The immune system of bats is very tolerant of pathogens and diseases that can be lethal to humans, like ebola and even some cancer cells. Bats are immune to many viruses and rarely show signs of disease so the visible white growth on the bats poses a huge threat to the ecosystem. Dr. David Blehert worked with Dr. Verant at the USGS National Wildlife Health Center and the WNS is scary because “here we have an animal that can survive some of the scariest viruses we know, and it’s undone by a common soil fungus.”

Brown Long-eared Bat

Brown Long-eared Bat

 

Main Article:

http://www.science20.com/news_articles/winter_hibernation_energy_drain_how_whitenose_syndrome_kills_bats-151997

Other Articles of Interest:

http://www.eurekalert.org/pub_releases/2015-01/usgs-hdw010215.php

http://www.nytimes.com/2015/01/13/science/no-time-for-bats-to-rest-easy.html?ref=science&_r=0

http://www.biomedcentral.com/1472-6793/14/10

http://en.wikipedia.org/wiki/White_nose_syndrome

 

Powered by WordPress & Theme by Anders Norén

Skip to toolbar