Arbovirus -- Flaviviruses -- Encephalitis Viruses Flashcards
Describe the genetics.
+ssRNA
Icosahedral Capsid
Envelope
Where do flaviviruses replicate?
Cytoplasm
Name three encephalitis flaviviruses.
St Louis Encephalitis
Japanese Encephalitis
West Nile Virus
Name Two Hemorrhagic Fever Viruses
Dengue Fever Virus
Yellow Fever Virus
Clinical Presentation of St Louis Encephalitis
Mild-Moderately Severe (in older patients)
Initial – Fever, Nausea, headache, vomiting, tiredness
In Severe Cases – Encephalitis, Long-term disability, death
Who should watch out for St Louis Encephalitis?
Patient over 50
What happens to patients with St Louis Encephalitis?
Primary viremia spreads virus to reticuloendothelial system
Secondary viremia leads to CNS infection
Neuronal Degradation/Necrosis
Spongiform changes
Where in the US is it?
Widely Distributed. (maybe esp. mid and south western
St Louis Encephalitis Treatment?
Just Symptoms
Clinical Presentation of Japanese Encephalitis.
Early – Fever, Diarrhea, Rigor, Headache, Seizures, Photophobia
Late – Flaccid paralyisis, parkinsonian syndrome
Fatal Cases – Slip into coma
Pathogenesis of Japanese Encephalitis
Enters body
Multiplication in reticuloendothelial system, viremia
Transport to brain via blood
Prolif/Damage brain
Transmission of Japanese Encephalitis.
Cycles btw mosquito, birds, and mammals
Humans are a terminal-carrier
How is Japanese Encephalitis controlled?
Mosquito control
Pig Control
Human Vaccination
Three manifestations of West Nile Virus?
Asymptomatic Infection (80%) West Nile Fever (19%) Neuroinvasive Disease (1%)
Symptoms of West Nile Fever.
Fever, Chills, Severe Headache, Rash, Aches
