Flaviviridae Flashcards
Examples of Flaviviridae
Yellow Fever, Dengue, Zika and West Nile Virus
What are arboviruses?
Transmitted by arthropods (arthropod-borne)
What are Yellow Fever, Dengue, Zika and West Nile Virus all transmitted by?
Mosquitoes
Yellow Fever Vector
Aedes mosquito
Cycle of transmission for yellow fever
[jungle (sylvatic) or savannah(intermediate)] and [urban] cycles
The two phases of yellow fever (pathology)
Viremic stage
Toxemic stage
What occurs in the viremic stage?
for 3 to 6 (can be 10-15) days before fever, severe headache and back pain
What occurs in the toxemic stage?
high fever, headache, back pain, nausea, vomiting, abdominal pain
Symptoms of yellow fever
black vomit
petechial and purpuric haemorrhages (bruising)
deepeing jaundice
more protein than usual in urine (kidney damage)
late stage - heart attack, arrhythmia, seizures, coma, confusion
What does petechial mean?
small (1–2 mm) red or purple spot on the skin, caused by a minor bleed from broken capillary blood vessels
What does purpuric mean?
Bleeding into the skin or mucosa from small vessels (bruising), smaller petechiae (1-2 mm in diameter)
Why is the liver important in the pathology caused by the yellow fever virus in infections of human hosts?
Molecular chain reactions induce a pro-inflammatory cytokine secretion – leads to vasculopathy and organ dysfunction. Overall cytokine imbalance damages cells and tissues.
What in the immune system facilitates viral replication in a yellow fever infection?
Dendritic cell facilitates viral replication
What in the immune system facilitates viral replication in a yellow fever infection?
Dendritic cell facilitates viral replication
What is the cause of a cytokine storm?
Severe up-regulation of a pro-inflammatory response (immune system).
