Neurological Viruses Flashcards
EEE & VEE Genome
+ssRNA
EEE & VEE Virion
enveloped
EEE & VEE Incubation
4-10 days
EEE & VEE Reservoirs
Reservoirs are Birds and small mammals
Common vectors are mosquitos and ticks
EEE & VEE Replication
In the Cytoplasm
Virus brought into the cell be cell-mediated endocytosis
EEE & VEE Symptoms
Chills, fever, malaise, arthralgia, myalgia
These last for 1-2 weeks
EEE & VEE Transmission
Introduced through the bite of an infected arthropod
Cells are infected locally and carried by Langerhan cells to LN
Replication and release into the blood stream where the infection spreads to CNS
EEE & VEE Complications
Can lead to Encephalitic disease in 5% of cases
- fever, headache, irritability, restlessness, vomiting, diarrhea, convulsions, and coma
- 1/3 of encephalatic cases die 2-10 days after onset
- Those who survive can have long term consequences such as seizures, personality disorders, and paralysis
EEE & VEE Prevalence
Seen mostly in eastern states
EEE & VEE Prevention
A single vaccine is available -TC-83
- contains live attenuated TC-83 and inactivated C-84
- only given to at risk military personel and researchers
EEE & VEE Treatment
No treatment, just supportive care to make the patient comfortable
West Nile Virus Genome
(+)ssRNA
West Nile Virus Virion
Enveloped
West Nile Virus Incubation
2-14 days
West Nile Virus Replication
Cytoplasm
West Nile Virus Symptoms
Most are asymptomatic
Illness occurs in 20% of cases
Fever, headache, malaise
West Nile Virus Transmission
Bites from infected arthropods
West Nile Virus Complications
Neuroinvasive in <1% of cases
- Aseptic meningitis, encephalitis, flaccid paralysis, altered mental state, tremors
- 50% of survivors have Sequelae 12 months later
West Nile Virus Prevalence
Fairly wide geographic range in the US
West Nile Virus Treatment
Supportive Care
No antivirals
Rabies Genome
(-)ssRNA
Rabies Virion
Enveloped
Rabies Incubation
30-90 days
Rabies Replication
Cytoplasm
Genome order dictates abundance of transcripts and protein
Binding of Protein N to RNA triggers genome replication
Frequently produces defective interfering particles
Rabies Symptoms
Prickling or itching where bitten, fever, malaise, headache
Hydrophobia
Cerebral dysfunction - anxiety, confusion, delirium, hallucinations and insomnia
Once symptoms appear, the disease is nearly always fatal
Rabies Transmission
Bite of infected animal
15% of bites cause disease; 60% if bite is on the face or head
Reservoirs are bats, skunks, raccoons, and dogs in developing countries
Rabies Complications
Replicates locally until it finds neurons, then it moves passively in the axoplasm of peripheral nerves to spinal glia, spinal cord, and brain
Spreads back to the periphery, highly innervated salivary glands, and replicates
Rabies Prevention
Vaccines available
Rabies Treatment
Post exposure prophylaxis
-4 doses - immediately, 3, 7, and 14 days after
-Should be administered immediately because it takes a while to develop
Patient should also receive immunoglobulin
