CNS Virus Flashcards

1
Q

Define Neurotropic

A

capable of replicating in nerve cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define neuroinvasive

A

capable of entering or infecting the CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define neurovirulent

A

capable of causing disease within the nervous system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What’s myelitis?

A

infection of the spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the most common causes of viral meningitis?

A

herpes simplex virus
rabiesvirus
arbovirus
enteroviruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What’s the pathophysiology of postinfectious encephalomyelitis

A

inflammation and demyelination due to possible autoimmune damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What’s the pathophysiology of Guillain-Barre syndrome?

A

post-infectious (viral) inflammation and demyelination leading to partial or total paralysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

T/F Most people can recover completely from guillain barre

A

True, 75% of people recover within weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the presenting symptoms of Reye’s syndrome

A

cerebral oedema, and a lot of swelling but not inflammation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what’s Reye’s syndrome caused by

A

post-infection with influenza or chickenpox

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

T/F Reye’s syndrome may be associated with administration of paracetamol to treat fever

A

False, it is linked to aspirin administration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What’s the pathophysiology of chronic demyelinating disease?

A

A late sequel to measles, which the antibody selects a specific strain of measles to infect CNS neurons, causing very slow onset sub-acute sclerosing panencephalitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How does virus get into the CNS?

A

infect PNS neuron
enter directly via blood stream, commonly the choroid plexus
via olfactory bulb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Why can’t we our immune system get rid of the virus inside PNS neurons

A

nerve cells don’t express MHCI to activate CD8 T cells’, and the intracellular pathogen cannot be cleared

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Where does the replication of virus in nerves occur?

A

at the soma of nerve, where virus can utilise host machinery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How does virus cause damage in the CNS?

A

direct killing of neurons
replicate in non-neuronal cells to cause demyelination
induce inflammation to allow entry of lymphocyte via BBB

17
Q

T/F Rabiesvirus must grow inside a nerve cell

A

True

18
Q

describe the shape and virus type of rabiesvirus

A

bullet shaped with helical capsid and envelop

It’s a -ve stranded RNA virus

19
Q

How does a virus exit the cell if it has an envelop?

A

budding

20
Q

T/F Rabiesvirus actively evades the immune system

A

False, it displays glycoprotein on the cell surface and can be targeted by antibody

21
Q

What are the symptoms associated with rabies

A

aggression

thirst but unable to drink water

22
Q

Why does rabiesvirus cause muscle spasm upon attempt to drink water (what’s the logic of it)

A

Rabies spread via the saliva, and water will dilute the viral load

23
Q

Describe the life cycle of rabiesvirus

A
entry via a site of penetrated skin
contaminated saliva infect muscle cell
eventually reaches a PNS nerve 
works its way up to the CNS 
invades the salivary gland to spread
24
Q

T/F Vaccines are only useful prophylactically

A

False, there is a window to use vaccine against rabies virus after being infected (before virus enters the CNS)

25
Q

Describe the shape and type for alpha herpesvirus

A

large envelope, icosahedral shape

linear dsDNA genome

26
Q

What’s the primary infection site of herpes

A

mouth or the lip

27
Q

How does herpes infect body’s organs

A

hide in PNS nerve cells or spread as viremia to different organs. They can then spread to the CNS

28
Q

T/F Proteins are actively produced in latent herpes infection

A

False, there is no structural gene expression

29
Q

What keeps the herpes virus in the latent stage

A

CD8 T cells, hence virus can reactivate when immune system is compromised

30
Q

What is the reactivation phage called in herpes

A

Shingles, painful blisters that follow dermatome distribution

31
Q

T/F Poliovirus must grow in a nerve cell as part of the life cycle

A

false, they just accidentally get into nerve cells

32
Q

describe the shape and type of poliovirus

A

+ve stranded RNA virus with icosahedral capsid

no envelope

33
Q

How does poliovirus cause damage?

A

it’s cytocidal, killing cells in which they replicate

34
Q

Where does poliovirus typically replicate in the CNS?

A

anterior horn cells because there is a receptor for polio

35
Q

What kind of CNS symptoms can polio cause?

A

acute paralysis