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Neurology > Poliovirus > Flashcards

Flashcards in Poliovirus Deck (24):
1

Poliovirus is a member of what family?

Picornaviridae

2

What other viruses are picornaviridae?

common cold and hepatitis

3

What is the genus of poliovirus?

Enterovirus- which means it spreads via fecal/oral route and replicates in the GI tract

4

poliovirus morphology>

nonenveloped icosahedral capsule

5

WHat major symptoms does polio cause

flaccid paralysis called poliomyelitis

6

How many annual cases of polio worldwide

less than 1,000

7

Polio has been absent from US since>

1977

Absent from western hemisphere since 1994

8

Polio reservoirs?

Humans only...this combined with the few number of serotypes makes it easy to vaccinate agianst

9

Initial replication of poliovirus occurs where?

Lymphoid tissue of pharynx and gut. So the virus is present in the throat and the feces

10

Virus spreads to CNS and does what

destroys motor neurons

11

90% of polio infections are...

subclinical

12

Three types of disease caused by poliovirus

KNOW

- Abortive poliomyelitis- mild illness
- Aseptic meningitis- only 1-2% of those infected
- Paralytic poliomyelitis- risk increases with age, can affect just about any musculature, any paralysis after 6 months is permanent

13

Importance of secretory IgA immune response?

- Secreted by the gut, neutralizes the virus before it can be shed and thus can prevent spread of virus

14

Post-polio syndrome

increased weakening of muscles later in life

15

polio diagnosis

specimen collection from stool, rectal swabs, throat swabs, etc...
- neutralization assays are performed to confirm poilio
- vaccine strains distinguished from wild strains using specific antibodies

16

Polio is best inactivated with?

formaldehyde or chlorine

17

Poliovirus is resisitant to?

ethanol and detergents

18

Us recommends use of what vaccine

inactivated

19

inactivated vaccine called

Salk IPV

Advantage is that the inactivation prevents reversion to virulence

20

Disadvantages of the Salk IPV

- Takes four subcutaneous injections
- Protects against paralysis but not the spread of wild virus because soince it is subcu, you get a good IgG but no IgA

21

DO not use Salk IPV if allergic to

neomycin, streptomycin, or polymyxin B

22

Oral vaccine

Sabin opv

23

Advantages to Sabin OPV

cheap, oral admin, protects against paralysis and spread

24

Disadvantge of oral vaccine

Can revert to virulence during preparation or during shedding by participants