Ch 12 - Arboviruses Flashcards
enzootic host
a well apated vertebrate reservoir host. Predictably carries the virus
Epizootic host
intermittently carrries the virus due to spillover
enzootic host usually no dz or dz/death
no Dz
epizootic host usually no dz or dz/death
can be assosciated with Dz or death
Which host is usually a dead end host? (epizootic/enzootic)
epizootic
What is the primary determinant/characteristic of a dead end host?
they do not typically generate a high enough viremia to transmit back to the vector
Why is Venezuelan Equine Encephalitis virus (VEEV) an exception concerning transmission from a dead end host?
VEEV does cause a high enough viremia in an epizootic host to transmit back to the vector
Arboviruses are mostly RNA or DNA viruses
mostly RNA
Bluetongue and EHDV target cell/organ
endothelium
Bluetongue and EHDV types of Dz
hemorrhages, infarction
EEVs, WNV target cell/organ
brain
EEVs, WNV type of Dz
Encephalitis
Arboviral Diseases usually localized or systemic
systemic
Arbovirus predominant disease syndrome depends on what 3 things
- virus
- nature and effectiveness of immune response
- target organ of virus replication
Are arboviral infections contagious or non-contagious?
non-contagious
Are the vectors of
arboviruses biological or mechanical?
biological (mosquitos)
What part of the brain does EEV replicate within?
cerebral cortex
What part of the brain does WNV replicate within?
brainstem and spinal cord
WNV: which epizootic host has the portential to transmit back to the mosquito vector?
Corvids
Dx for WNV?
CSF, Titer for anti-WNV IgM, PCR, IHC
BTV and EHDV Dz in sheep and wild ruminants
systemic vasucular Dz
BTV and EHDV Dz in cattle
reproductive Dz
Vector for BTV and EHDV?
biting midge
Can BTV and EHDV reassort? If yes, why?
Yes, they have a segmented RNA genome.
BTV/EHDV target
endothelium
Major diseases of BTV and EHDV
hemorrhagic and reproductive
