VIRAL CNS

Question 1

What is caused by Picorna virus?

Answer 1

Polio

Question 2

What is paralytic poliomyelitis?

Answer 2

Asymmetric flaccid paralysis from lower motor neuron damage

- Severe but rare

Question 3

What vaccine is used for Polio in the US, and why? What does it prevent?

Answer 3

IPV

• OPV can back mutate
• PREVENTS sxs/paralysis (virus still circulating so does not prevent infection)

Question 4

For arboviruses generally, what two organisms are vectors? What two are reservoirs?

What are humans considered?

Answer 4

• Vectors: mosquitoes, ticks
• Reservoirs: birds, small animals

Humans = dead end host

Question 5

What is Post-Polio Syndrome, and what causes it?

Is it infectious?

Answer 5

Muscle weaknesss/pain 30+ AFTER acute paralyzed polio

• Due to overuse progressing to failure of motor units
• NOT infectious

Question 6

What is the etiology of West Nile Virus, and what two conditions is it closely associated with?

Answer 6

Flavivirus

• Yellow Fever (YF)
• St. Louis Encephalitis (SLE)

Question 7

Why is West Nile Virus difficult to diagnose?

Answer 7

Antigenic crossing with YF and SLE

Question 8

What diagnostic tool is used for West Nile Virus, and what is seen?

Answer 8

MAC-ELISA shows IgM antibody for WNV

Question 9

What can induce a false + IgM titer for West Nile Virus?

Answer 9

YF/SLE vaccination

Question 10

What is the primary prevention for West Nile Virus?

Answer 10

Interrupt chain of transmission

Question 11

What are two routes of transmission for Zika Virus?

Answer 11

• Mosquitoes

- Sex (STI)

Question 12

What two diagnostic tools can be used for Zika Virus? What should be considered?

Answer 12

• PCR
• MAC-ELISA

Possible antigenic crossing with YF

Question 13

What are two severe concerns associated with Zika Virus (i.e. what can it cause)?

Answer 13

• Teratogenic

- Can cause GBS

Question 14

What are two possible transmission routes of Rabies?

Answer 14

• Animal bite

- CRYPTIC

Question 15

What is Cryptic Rabies?

Answer 15

Simple contact with an infected animal causes infection

- Ex. BATS

Question 16

Is the incubation period for Rabies short or long, and what is the most important stage?

Answer 16

LONG incubation

- Excitatory stage: “furious” in dogs; anxiety and apprehension hydrophobia in humans

Question 17

What three preventative measures can be taken with Rabies?

Answer 17

• AVOID exposure
• Prophylactic vaccination of animals
• Immunization post-exposure

Question 18

What two things should be administered as post-exposure immunization?

Answer 18

• HDCV (Rabies vaccine)

- Hyperimmune serum