Its Official: Fungi Kick Mammalian Butt

Bats with WNS

Since 2006 certain species of hibernating bats have been dying off in dramatic fashion by what has been called White Nose Syndrome (WNS). It is named as such because of some fungal growth around the nose of many affected bats. In 2008, Blehert and colleagues identified the fungus as Geomyces destructans and showed in early 2009 that the fungus was widespread throughout affected populations. In previous posts on these issues, I raised concerns because there was no data demonstrating causation. In fact, while noting that G. destructans could indeed be the etiologic agent of WHS, I also noted that it could be an indirect effect of some underlying problem. For example, the bat immune system could be impaired by a biological or chemical agent that allows G. destructans to infect and ultimately kill the bats (akin to HIV in people).

Well Lorch et al report in Nature that G. destructans is directly causing WNS in bats. Lorch et al essentially test the third of Koch's postulates, which are:

1. The microorganism must be found in abundance in all organisms suffering from the disease, but should not be found in healthy organisms.
2. The microorganism must be isolated from a diseased organism and grown in pure culture.3. The cultured microorganism should cause disease when introduced into a healthy organism.
4. The microorganism must be reisolated from the inoculated, diseased experimental host and identified as being identical to the original specific causative agent.

Now even Koch realized his postulates are not universal laws. For example, asymptomatic carriers kind of screw over postulate #1 and non-culturable organisms make #2 an impossibility. However, when fulfilled even partially, these postulates provide powerful information in the etiology of disease.

In the case of G. destructans, postulate #2 was fulfilled previously. In the study by Lorch et al, postulate #3 is shown to be true. If you grow G. destructans in culture and then expose healthy (but susceptible) bats to the fungus, they get l00% infection (Treated in table below), but similarly treated, but without the fungus, control animals should absolutely no development of WNS. More than 95% of infected bats succumbed to WNS within 3 months on infection! (Although it sucks for the bats, this provides definitive evidence that the fungus is the causative agent of WNS!!!1111!

Nature Table 1 (partial)

Furthermore, the authors found the fungi in lesions on the wings where most of the disease damage is thought to occur (despite the 'nose' being part of the name). This helps fulfill postulate #4.

This work is important because it affixes a firm target on the culprit. We can rule out other biological or chemical agents causing susceptibility to WNS. This also helps deal with postulate #1. Postulate #1 has been a complete dick in the case of WNS. This is due to the fact that G. destructans is found associated with European bats that are healthy. What Lorch et al's work tells us is that the situation is more complex than initially realized (but the truth of the matter is that life is always more complex). Maybe European bat species have immune mechanisms that prevent WNS. Maybe the G. destructans strain in the US is more pathogenic than the European isolates. Regardless, these are testable hypotheses. We can also definitively add mammals to the animals fungi feed on. Happy Halloween!


Lorch, J., Meteyer, C., Behr, M., Boyles, J., Cryan, P., Hicks, A., Ballmann, A., Coleman, J., Redell, D., Reeder, D., & Blehert, D. (2011). Experimental infection of bats with Geomyces destructans causes white-nose syndrome Nature DOI: 10.1038/nature10590

Amy Dickinson: Dumbass

Amy Dickinson: First ever awardee!! Grats Amy!

This week in the Star Tribune advice column (it's next to the crossword so I often read it), Amy Dickinson responds to a young adult grappling with their non-belief. The concerned 16 year old no longer wants to attend services and is worried that when the subject is broached, their mother would enroll them in some kind of religious counseling. Admittedly, this is a tough one and these kinds of discussion can tear families apart. However,  it is my experience that it is the religious person that tears the family apart, not the non-believer. The religious authoritarian mother or father can not abide the non-believer/gay/evolution supporting/democratic/sexually active child and throws them out or worse. Now these specific parents may be completely ok with their child having different beliefs, but there are reasons why this 16 year old may be concerned.


So what is Amy's 'advice'?

You could show how mature you are by seeking the advice of your clergy on your own before discussing this with your folks.
This is a familiar issue, and a compassionate pastor may actually encourage your parents to give you more space.

Yep, if you do not believe a certain religious dogma, then you should seek the advice of the sellers of the dogma. If you want to stop smoking cigarettes, don't consult a doctor, go see a Philip-Marlboro representative. If you are concerned you are gay, don't talk to a counselor with expertise in sexuality, go see Marcus Bachmann's faith-based reorientation counselors.


Did it occur to Amy that the clergy member has a vested interest in retaining this soul for Allah, Jesus, Zeus, whomever? Yes, a compassionate pastor may be helpful, but is it worth the risk to the 16 year old to take this chance? What if you are wrong Amy? It is worth noting the 16 year old is concerned about being entered in religious counseling. Doesn't that suggest the parents may not belong to the most empathetic sect on the planet? Why send the young adult to the clergy and not a humanist? It seems Amy's advice serves to cater to the parents' potential needs and not the 16 year old's.