Plagues Final Exam

Occurs in goats (scrapie/ovine spongiform encephalopathy), humans (kuru/CJD), cows (mad cow/bovine spongiform encephalopathy), and white tailed deer (chronic wasting disease). spongiform = holes in brain tissue, looks like sponge. encephalpathy = encephalon (brain). spongiform encephalopathy = disease of the brain and/or CNS caused by prions.

Have been known for a long time even though not named spongiform encephalopathy. knew as scrapie, associated with sheep -> mange, unstable walk, dies within 1-2 days. bovine spongiform more recent concern - began in u.K. first case around 1986

Devastating impact on livestock in U.K. - only way to control is to kill all infected cows. strted in 1984 on farm - vet made diagnosis, over 100 cows died from same disease within 1-2 weeks. specific bovine offal (head tissue of cows) was baned early on, then meat nd bone meal was banned.

Cannibalism - cattle wer forced to be cannibalistic - took unsold parts, ground up and fed to cattle. cows are usually herbivores. people thought if cows eat cows and get MCD, what about us?

Minister of Agriculture John Gummer publicly ate beef in 1990, led campaign to raise awareness that beef is safe. in 1995 stephen Churchill, age 19 dies -- one of 1st cases, affected healthy, young people. 167th victim of vCJD in 2007 was Gummer family friend Elizabeth Smith (age 21)

Saw with rise and fall of MCD was also rise and fall of human disease - called creutzfeld-jakob disease (CJD). CJD was human version of MCD, had been around before MCD. a neurodegenerative disease, invariably fatal, long incubation periods (chronic) - may be years before sick enough to die. was of unknown etiology (what caused it?)

Sympton of CJD - cynical laughter, permanent grins on face, what joker suffered from in batman

Won nobel prize for work on s. encephalon. working for NIH in 60s when foumd strange illness in Papa New Guinea - tribal people - hundreds/thousands dying of disease known as "kuru". he went there to investigate, accumulated tosn of info, noticed people had cannibalistic behavior in society - when loved one died, would eat part of body. noticed when practiced different pople ate different parts of hte body - males got fleshy tissues while children and women got parts like the brain (women more likely to get kuru, associated wih consumption of tissues of CNS). Kuru = CJD = transmissable spongoform encephalopathy (TSE) - transmitted in eating tissues. carleton was predator, adopted and lived with young boys

1. sporadic CJD - not sure why
2. familial (inherited) CJD
3. acquired by infection (environmental)
-can be both infectous and non-infectious. sporadic comes later in life, maybe genetic but not sure. inherited CJD from genes with mutations (amino acid changed). sporadic CJD makes up 90% of cases. environmental is acquired by consumption or contamination with infected patient tissues or fluids. source of infection can be human or animal (cannibalism, consumption of infected meat - also known as vCJD or mad cow in humans, latrogenic sources - as a result of medical treatment (ie tissue graphs for head injuries) - since '88, 100 deaths from latrogenic CJD from dura meter graphs from cadaver. also in 1986, patients who'd received growth hormone therapy began to contract CJD (HGH harvested from pituitary gland of cadaver)

Probably derived from bovine spongiform encephalopathy (BSE), a.k.a mad cow disease. average age, 28 years, 93 cases bw 1994-2001 (relatively rare) - more than are killed by lightning strikes

PNG = papau new guinea

NY state - in white tailed deer and in middle of country

1. parasites: protozoa (malaria), worms (filariasis)
2. bacteria (yersinia)
3. fungi (candida)
4. insects (scabies mites)
5. viruses (HIV, Ebola, etc.)
- none of these things cause prion - only example of ingectious disease not caused by virus, fungi, etc. agent does not fit kingdom, cell count or cell type. CJD does not have DNA/RNA

Neither eukaryotes nor prokaryotes. suingular, but not cellular (are exception)

Griffith found relation between DNA and RNA and proteins. Avery also studied DNA