Controversial Research: Bacteria, Not Prions, Cause CWD

by Darren Warner, D&DH contributor

Mule deer with CWD
A mule deer affected by chronic wasting disease (CWD) stands in an enclosure. CWD affects members of the Cervidae family (whitetail deer, mule deer, moose and elk) and many sub-species. (Photo courtesy of Photo Courtesy of Wyoming Game and Fish Department)

In 1982, neurologist Dr. Stanley Prusiner discovered the prion, a misfolded protein believed to cause transmissible spongiform encephalopathies (TSEs) or brain diseases like chronic wasting disease (CWD), mad cow and sheep scrapie. Prusiner won a Nobel Prize for his achievement, setting off a flurry of prion-based research. Today, 99 percent of scientists believe prions cause CWD – Dr. Frank Bastian isn’t one of them.

“Spiroplasma causes TSEs like chronic wasting disease,” said Bastian. “The bacterium likely initiates the disease process and stimulates the formation of prions, but more experiments are needed to confirm this.”

Spiroplasma is a group of microscopic bacteria that lack cell walls and can’t be killed with antibiotics. Bastian recently injected strains of spiroplasma into laboratory deer, sheep and goats. The Louisiana State University researcher’s findings, published in Veterinary Ophthalmology (2011), will likely change what we think we know about the cause of CWD. After just 3.5 months, deer showed clinical symptoms of CWD. Goats and sheep developed swollen brains at 12 months, and lab tests later confirmed they were infected with a TSE.

Proponents of the prion theory have been slow to embrace Bastian’s research.

“There are very few individuals studying the cause of TSEs like chronic wasting disease, and what happens is that those who are decide what’s behind these diseases, and then they put that out to the media and write it in textbooks,” explained Dr. Laura Manuelidis, a professor and researcher of neuropathology at Yale Medical School. “Then what happens is that one theory gets written in stone, which hampers new research.”

In the world of TSEs, Bastian conducts experiments on a research island. He refuses to be led by the prevailing winds of the prion explanation, mainly because there are problems with the prion theory. Prion scientists can’t explain why the protein isn’t present in five to 10 percent of all infected animals, can’t reproduce prions in the lab (the gold standard for scientific explanations) and can’t explain how prions change into different diseases.

Bastian’s work provides new hope for managing CWD. If scientists can generate antibodies against spiroplasma, it will enable them to detect CWD earlier. It may even provide a means of creating a vaccine.

One thing’s for sure: If we don’t know what causes CWD, there’s little chance of managing it. We can only hope that more scientists will review Bastian’s research and join him on his island.

UPDATE: Fast forward to the 6:22 mark of this video and listen to John Eveland’s remarks about the Bastian research and plans for more work on potential cures.

 

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