Neurological Viruses

Question 0

Transmission of Neurological Viruses

Answer 0

transmission requires replication in the vector

Question 1

Common vectors and reservoirs of neurological viruses

Answer 1

arthropods
common vectors: mosquitoes (culiseat, aedes, culex) & ticks
reservoirs: birds & small mammals

Question 2

EEE & VEE Virus Biology

Answer 2

Togaviridae
Genome: (+)ssRNA
virion: enveloped

Question 3

EEE &VEE Virus Disease

how is it introduced into an organism, process of infection, type of disease

Answer 3

introduced via bite of arthropod
infects locally or can be carried to lymph nodes by Langerhans cells
replication and release into the blood stream
infection in other target organs &CNS

Question 4

EEE and VEE Virus Disease
incubation period
type of disease and description

Answer 4

incubation period: 4-10 days
systemic disease: typical sickness, arthralgia and myalgia, 1-2 weeks then full recovery

encephalitic disease: typical sickness, convulsions and coma, 33% of cases die 2-10 days after onset, those who recover can have long term sequelae (seizures, personality disorders, paralysis)

Question 5

EEE & VEE Prevention and Control

Answer 5

Vaccine: TC-83 attenuated, C-84 inactivated
no treatment
mosquito control strategies

Question 6

West Nile Virus

incubation, description, unique features

Answer 6

incubation: 2-14 days (80% have asymptomatic infections)
typical illness (20% of infections) duration is 3-8 days
neuroinvasive disease in <1%

Question 7

West Nile Virus neuro-invasive disease description

Answer 7

<1% of infections
aseptic meningitis, encephalitis, flaccid paralysis, altered mental state, tremors
50% of survivors have sequelae 12 months later

Question 8

West Nile Prevention and Control

Answer 8

no vaccine
no treatment
mosquito control strategies

Question 9

Describe the Rabies Virus

Answer 9

Rhabdoviridae
genome: (-)ssRNA
enveloped virion

Question 10

Rabies Virus Biology

Answer 10

Broad tropism
binding of N to RNA triggers replication
frequently produces defective particles

Question 11

Describe Rabies the disease

transmission, reservoir, incubation, spread

Answer 11

transmission via bite of infected animal

reservoir: bats, skunks, racoons, ect
incubation: 1-3 months, depends on location of bite
spread: replicates until it finds neurons, moves passively to CNS, spreads back to periphery to salivary glands

Question 12

Rabies symptoms

Answer 12

hydrophobia
cerebral dysfunction (anxiety, hallucinations, confusion ect)
once symptoms appear disease almost always fatal

Question 13

Rabies virus prevention and control

Answer 13

vaccine available (not very immunogenic)
post-exposure prophylaxis: as soon as possible, 4 doses: immediate, 3, 7 and 14 days. Should also receive RIG
vaccination of dogs and wildlife

Question 14

What are the neurological viruses we covered?

Answer 14

EEE: (+)ssRNA
VEE: (+)ssRNA
West Nile: (+)ssRNA
Rabies: (-)ssRNA