Cannibalism: A Perfectly Natural History(75)

In 1982, Prusiner published his lab findings on scrapie in the journal Science. He coined the name “prion” (pronounced “PREE-on”) to describe an aberrant form of protein, which he claimed was responsible for the suite of neurodegenerative disorders known as Transmissible Spongiform Encephalopathies (TSEs). Prusiner claimed that, unlike viruses, prions were not biological entities, but they could be infectious—transmitted orally or through contact with infected material. They could also be inherited or spontaneous in origin.

When asked about why the body’s immune system didn’t appear to mount a defense against them, Prusiner explained that unlike viruses or bacteria, prions weren’t foreign invaders; they were an altered form of one of the body’s own proteins. Because of this, the body never recognized them as a threat. As a result, prions would spread through the body of a TSE victim unchecked.

Prusiner did hedge his bets by stating that current knowledge did not exclude the potential existence of a small core of nucleic acid within the prion—which might explain how they replicated. Nevertheless, he co-opted Griffith’s protein-as-template model, with his misfolded prion proteins (which were too small to see with even the most powerful microscopes) building up into the amyloid plaques that characterized fatal TSEs like kuru, Creutzfeldt-Jakob disease, TME, and scrapie.



For his work on prions, Prusiner won the Nobel Prize for Medicine in 1997. Some have argued that he should have shared the award with other researchers, and they pointed to the fact that several people had been bumped out—or worse—by the self-promoting American. In his book Deadly Feasts, Pulitzer Prize–winning writer Richard Rhodes wrote that Prusiner “invaded and colonized the work of others in his apparent pursuit of a Nobel Prize.” Prusiner’s list of enemies grew even longer after accusations that he had used the peer review process to stonewall publication of another researcher’s results while submitting his own paper on a similar topic.



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50 “Downer cattle” is a trade term for cows that have become too sick to walk, or die before being slaughtered.



51 A category usually shortened to “the Nobel Prize for Medicine.”





19: Acceptable Risk


I have taken advice from the leading scientific and medical experts in this field. I have checked with them again today. They have consistently advised me in the past that there is no scientific justification for not eating British Beef and this continues to be their advice. I therefore have no hesitation in saying that beef can be eaten safely by everyone, both adults and children, including patients in hospital.

— Sir Donald Acheson, Chief Medical Officer, UK Department of Health, 1990

The kuru/Bovine Spongiform Encephalopathy (BSE) story now jumps to 1988.

Given the degree of bureaucracy inherent in a government such as Great Britain’s, many people would have been surprised that year if the ministry had reacted to epidemiologist John Wilesmith’s news on how BSE was being spread with an immediate ban on meat and bone meal, or even a warning. Instead, because they still believed that they were dealing with a disease that hadn’t been transmitted to humans, the government dragged its feet. Clearly, many officials were far more concerned with preventing a panic that might impact negatively on the rendering and beef industries than they were about the possibility of their citizens consuming prion-contaminated meat pies. The government also knew that closing rendering plants would have placed the burden of eliminating unwanted livestock parts squarely on the shoulders of the beef industry, a significant new expense that would have resulted in higher meat costs and a concurrent decrease in the competitiveness of British beef on the world market. So rather than demanding immediate and industry-wide changes, the politicians did something a bit less dramatic: They quietly called for the formation of a “blue ribbon” panel led by the eminent Oxford zoologist Richard Southwood. The “Southwood Working Party” met for the first time on June 21, 1988, and again in November and December of that year. The problem was that neither Southwood nor his three-member team had any experience dealing with spongiform encephalopathies.

Earlier in June, government officials met with members of the UK Rendering Association. On the strength of the data provided by Wilesmith, the ministry informed the renderers that they would be suspending the sale of ruminant-based protein (i.e., meat and bone meal) as a dietary supplement for cows and sheep. Although the ban went into place the following month, that would become the extent of the good news. Farmers were also asked to voluntarily stop feeding meat and bone meal to their cows. Unfortunately, many of them had already spent thousands of pounds on what had suddenly become an illegal nutritional supplement. But since the government hadn’t offered to buy the protein supplement back from them, and since there were no efforts to enforce the government’s request, there was little incentive for the farmers to stop using it. The results were predictable.

After quietly acknowledging the fact that removing infected cattle from the system was an important step in curtailing BSE, the ministry did decide to compensate cattle owners who turned in their visibly sick animals. But instead of offering to purchase the diseased cattle at market value, they low-balled the herd owners, offering them only 50 percent of market value for their animals. By comparison, the government was already handing out 75 percent of market value for cows infected with tuberculosis.