I recently wrote a post describing the decline of frog species due to the chytrid fungus. Batrachochytrium dendrobatidis, or Bd for short, is a waterborne zoosporic fungus that is currently infecting amphibian species all over the world; affecting the outermost layer of skin, the fungus makes it difficult for amphibians to osmoregulate and respire, leading to their ultimate demise. It is perhaps one of the greatest threats facing amphibians, with scientists estimating that this plague alone may wipe out 33% of the world's amphibians. Though some small scale treatments have proven effective, there has been no way to implement these treatments on a larger scale, and all attempts to slow the spread of the fungus have proven ineffective.
The researchers with the University of California, Santa Barbara have been working to rebuild the wild populations of the mountain yellow-legged frog (Rana muscosa). One of the greatest challenges they are faced with is the spread of the chytrid fungus which has decimated the yellow-legged frog population by about 90%. However, the researchers were hopeful that, with a little intervention and assistance, the frogs might be able to overcome the disease.
The team began collecting yellow-legged frogs and then did the unthinkable: they purposely infected them with the deadly fungus. Before the fungus could kill the frogs, the team treated and eventually cured them using anti-fungal medications, before releasing the frogs back into the wild. The idea was to create a sort of "chytrid vaccine", which would strengthen the frogs' immune systems against future infections of the fungus, thanks to their previous exposure.
“It’s the best chance that we know how to give them.” -Roland Knapp, a biologist with UC Santa Barbara Source
So far, this vaccine method has proven promising, with all the treated frogs surviving pretty well (at least against the threat of chytrid). In fact, they are doing so well that the San Francisco Zoo has begun similar immunity treatments for other species of vulnerable frogs.
This is not a cure for chytrid. And while it may be possible to aid smaller populations, the disease still spreads world-wide (and there is no possible way to even come close to offering immunity treatments for all the amphibians at risk). But the immunity treatments are a promising start; even if they do not stop the spread of chytrid, the amphibians' heightened immunity will slow the spread, allowing us a little more time to figure out how to eradicate the disease. Researchers are hopeful that these treated frogs will also naturally pass on the immunity traits to their offspring, creating future generations that are more resistant to the disease. It's a small step forward in the battle against chytrid, but it's proof that amphibians are not necessarily out of the picture yet!
Source: http://www.reptilesmagazine.com/Researchers-Infect-Mountain-Yellow-Legged-Frogs-With-Chytrid-Fungus-In-Order-to-Save-Them-trending/