Friday, October 24, 2014

A Chronic Wasting Disease primer - adjunct to the immediately previous blog post

The prion’s very name says it all: Derived from “protein,” a prion is an infectious misshapen protein.

It is not a living entity; not even on the order of the simplest bacteria. Nor is it a virus, which more than a few scientists say is a “thing” that is “almost life.”

Prions have neither DNA nor RNA. It attacks mammals only and is considered what’s called a transmissible spongiform encephalopathy disease that recruits via converting healthy proteins into the misshapen form.

In effect, the prion seeks to duplicate itself over and over again. As this insidious process expands, holes in an infected animal’s nervous system – including and perhaps, especially, the brain – develop. Such a condition results in the organ becoming sponge-like matter; hence the application of the word “spongiform.”

As a result, some scientists refer to prions as “killer proteins.”

Consequently, something so seemingly simple that isn’t even alive is a complex process that still baffles the scientific community. The Centers for Disease Control notes this paradox by saying that prions “… are still not completely understood” yet notes that “Prion diseases are usually rapidly progressive and always fatal.”

In humans, the Disease Centers also say, they are four known prion-linked disease. Chronic Wasting Disease is not one of them.

The Disease Center says as well that science knows of six prion-linked diseases in animals, CWD being one of them.

Known CWD- impacted animal species include elk, white-tailed deer, mule deer, and moose, the Disease Centers says.

Though the delivery mechanism is yet to be fully understood the Disease Centers does say that scientific speculation suggests direct animal-to-animal contact and/or “indirect exposure” through CWD-contaminated food or water sources are likely the culprits.

Yet while such organizations as the Chronic Wasting Disease Alliance says that research “suggests that humans, cattle and other domestic livestock are resistant to natural (CWD) transmission” such infection still “remains a concern.”

This, in spite of the fact that no human has been known to contract CWD under any circumstances, natural or otherwise.

The Illinois Department of Natural Resources says that disease signs in deer include excessive salivation, loss of appetite, progressive weight loss, excessive thirst and urination, listlessness, teeth grinding, and holding the head in a lowered position as well as drooping ears.

Likewise, the agency says an infected deer may not display symptoms for as many as 18 months.

“In fact, 94-percent of the deer from Illinois that have tested positive for CWD have otherwise appeared healthy,” the agency says in a question and answer document on the subject.

- Jeffrey L. Frischkorn

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