Rabies and Prions Flashcards Preview

Med Triple I > Rabies and Prions > Flashcards

Flashcards in Rabies and Prions Deck (17):
1

Source of rabies

Any mammal. Skunks, foxes, coyotes are common, bats are very common, rodents - rarer.

2

Rabies incubation

Can be days to years, travels from sensory nerve to CNS (longer distance, longer incubation). Once symptomatic, almost always fatal.

3

Rabies virus characteristics

-ve sense RNA, Rhabdovirus

4

Clinical presentation

Prodrome: fever, sore throat, chills, headache, pain at bite. Neuological: agitation, restlessness, hyperactivity, salivation. Leads to dysphagia (hard to swallow), stupor, coma, death in 4-20 days

5

Rabies diagnosis

Hx, clinical, biopsy - nuchal, CSF then detect Ag or do PCR

6

Rabies Antiviral treatmet

NONE. Invariably fatal once it has “begun”

7

Rabies treatment

Clean wound. Get Rabies Ig. vaccine - pre-exposure: for animal handlers; post-exposure: following animal bites

8

Rabies postexposure prohylaxis

Inactivated virus. Give several times (few days apart). Very safe (early vaccines had lots of issues)

9

Prions - what are they?

When initially studied they thought it was a slow virus, but couldn’t find RNA/DNA. Basically they are some infectious proteins. Proved because it was resistant to nucleases, UV, etc.

10

Prion disease examples

Kuru, Crutzfel-Jakob diseases (cause dimensia), Variant CJD (ie mad cow)

11

Prion pathology

sponge appearance. No inflammatory cells (self protein, so no immune response)

12

Prion protein - what’s different?

Single a.a. mutation resulting in change in protein folding (less helix, more ß sheet). Requires some “normal” protein to be present too

13

Creutzfeld-Jakob Disease

Usually in older people. 80% sporadic. Progresses rapidly. Early onset Dementia (40-50), death within 3 years. 100% fatal.

14

Variant CJD

Onset is much younger. Associated with BSE contaminated beef (but there is a genetic disposition, not everyone got it). 100% fatal

15

BSE

sporadic cases will be reported. But extremely low risk to humans.

16

Chronic wasting disease

Deer, elk. No human transition to date.

17

Protein folding diseases

Include things like alzheimers. Potential to slow them with pharmaceuticals or vaccines.