Listen to the prions

Prion? This is the name given to the elusive and rather weird infectious agents behind all transmissible spongiform encephalies — mad cow disease (BSE - bovine spongiform encephaly); scrapie in sheep, chronic wasting disease (CWD) in elk and deer, transmissible mink encephaly and Creutzfeld Jakob Disease (CJD) in humans.

In 1982, Stanley Prusiner came up with the name “prion” for what he described as “proteinaceous infectious particles which are resistant to inactivation by most procedures that modify nucleic acids”. Prions cause misfolded proteins, and despite lacking DNA, they are nevertheless self-replicating, or more accurately, they replicate by causing neighbouring proteins to similarly misfold and clump together, destroying cellular tissue resulting in tiny holes that turn brain tissue spongy. Some researchers suggest that a prion can arise spontaneously, others that it is a form of virus, but what initiates the process, or where a prion comes from, we just don't know. Which means that anyone who makes a definitive statement about prions or about the diseases they cause is, to put it politely, speaking out of turn.

In 1986, mad cow disease hit British cattle, and before it was brought under control, tens of thousands of cattle were destroyed (incinerated and/or buried) and the disease had been passed to humans, defying all the complacent and then panicked assurances of British government officials.

Among the uninformed assurances — all supposedly science-based — were that the infectious agent could not pass from one species to another and that it was only transmitted by cattle feed containing rendered brain and spinal cord tissue from infected cattle. In due course, however, it came to be realized that neither of these assurances was true.

The fact remains that even today, very little is known about the transmission and functioning of this disease, and when Paul Mayers, a spokesman for Health Canada, says that there is no reason for Canadians to be worried about eating beef at this time — “To date, any risk related to human health remains low” — he is really speaking out of turn, as there is no basis on which to make such a statement.

But perhaps it would be better to listen to the prions themselves. After all, they are the agents in all this.

Prion #1: You know, we might never have become a cause c

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