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Brain Eater, The
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Viewing Ideas
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Before Watching
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While infectious diseases are generally caused by living
organisms, some scientists suspect that Mad Cow Disease is
caused by a non-living protein molecule. This is a radical idea
in the world of biology because proteins have no known way to
replicate and, therefore, spread the disease. Prepare students
to consider this hypothesis by first having them brainstorm what
they know about the more common viral and bacterial diseases. On
the board, write as many diseases as students can think of and
then group them into the following categories: Infectious
(Contagious, or "Catching"), Non-Infectious ("Not Catching"),
and Not Sure. Create a chart and have students answer the
following questions for each disease: What causes the disease in
people? How is it spread? How can it be prevented, cured, and/or
contained?
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This program profiles different forms of the disease
transmissible spongiform encephalopathy. Before watching, you
may want to review with students each form of the disease and
what species it affects. See Same Disease, Different Names for
more information.
Same Disease, Different Names
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Form of spongiform encephalopathy
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Species infected
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How infected
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When infection first detected
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scrapie |
sheep |
infectious agent unknown; thought to be diet-based
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been in Britain for at least 200 years and in the United
States since 1947; has existed in sheep in most countries
worldwide
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bovine spongiform encephalopathy (BSE), or Mad Cow Disease
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cows |
most likely through a food supplement that contained
scrapie-infected sheep
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1986 in British cattle |
kuru |
humans |
through cannibalistic rituals using deceased relatives
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early this century in a Papua New Guinean group called
Fore
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Creutzfeldt-Jakob disease (CJD)
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humans |
naturally occuring in one of every million people worldwide;
mostly affects 50- to 75-year-olds
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1920 |
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new variant Creutzfeldt-Jakob disease (nvCJD)
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humans |
most likely through eating meat products infected with BSE
from cows
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1994-1995 in young adults who fell ill
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transmissible mink encephalopathy (TME)
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mink |
possibly through sheep with scrapie
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first U.S. outbreak in 1947
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