chapter 19 rabies

how can rabies be prevented after a bite has happened?

vaccination

what is the structure of rabies?

bullet shaped with the viral envelope wrapped tightly around the RNA genome, which in turn is wrapped in the nucelocapsid. The nucleocapsid and RNA forms a helix, with one end protruding slightly giving the bullet appearance

how many viral proteins are there?

5; 4 of which are structural

what are the 4 structural proteins

glycoprotein (which binds receptors on cells), matrix protein, the nuceloprotein (which forms the nucleocapsid) and the polymerase

what is the one nonstructural protein associated with?

polymerase

what is the genome of rabies?

single stranded, negative sense RNA genome; linear and nonsegmented

• because it is a negative sense genome, the virion must contain copies of the viral RNA dependent RNA polymerase so positive sense copies can be made

how is rabies spread?

animal bites (dogs, bats, foxes, skinks, racoons and coyotes)

what happens once rabies gets inside of your body?

begins replicating in muscle tissues; after, in will enter the nerve cells and uses the transport system to reach the brain (the closer to the brain the bite it, the faster the disease will manifest itself)

what symptoms does rabies causes

numbness and tingling at the bite site, but normally there are very few symptoms until the rabies virus reaches the central nervous system

Rabies virus aims for the brain, what dysfunctions does it cause?

confusion, irritability, agitation, hallucinations, muscle spasms and paralysis; eventually person will enter coma and die (mortality is 100% once it reaches the central nervous system

where else does the virus infect besides the brain?

salivary glands (fills salive with infectious virions), throat (causes painful spasms when swallowing); this is what causes hydrophobia and foaming at the mouth of animals that are infected

how does rabies avoid the immune system?

infecting the nerves; also blocks interferon which shuts off the initial immune response and allows the virus to replicate and enter the nerves

what can you do to prevent rabies from being fatal?

since rabies takes so long to reach the central nervous system, there is time for the rabies vaccine to block the infection

What two types of immune-based treatments should be given to someone who has been bitten by a rabid animal? 

They will receive the rabies vaccine which will make their body make antibodies against rabies and immune globulin, which is premade antibodies against the virus which gives immediate protection