Viral Bioweapon Threats Flashcards
Category A
Viral agents of highest concern
- Smallpox
- VHF
- Filoviruses (Ebola/Marburg)
- Arenaviruses (Lassa)
Category B
Viral encephalitic agents
Alphaviruses (e.g., VEE)
Category C
Emerging pathogens
CCHF
Yellow Fever
Hemorrhagic Fever Viruses
Filoviruses: Ebola/Marburg
Bunyaviruses: CCHF (Congo-Crimean)
Arenaviruses: Lassa Fever
What is VHF?
Viral Hemorrhagic Fever
A severe multisystem syndrome in which the vascular system is damaged (body cannot regulate itself)
Usually accompanied by hemorrhage
What are the important Bunyaviruses
Hantavirus (transmitted by rodents)
CCHF (transmitted by the Hyalomma tick)
Genome of Filoviruses (Ebola/Marburg)
-ssRNA
Remember: All VHF viruses are enveloped RNA
Important Flavivirus
Yellow Fever
Weaponized by North Korea
VHF Tx
Supportive care is essential
Ribavirin (+ IFN-α): especially for arenaviruses and bunyaviruses
Are vaccines available for any of the VHFs?
Only 2:
Argentine HF (Junin Virus)
Yellow Fever
How many subtypes are there of the Ebola Virus
5
Zaire, Sudan, Ivory Coast, Bundibugyo, and *Reston
*Reston is not pathologic to humans (infects monkeys)
Is there a carrier state for Ebola?
NO
Acute illness only (still have to worry about nosocomial spread)
What does ambisense mean?
That the genoma has both + and - stranded DNA
Examples: CCHF and Lassa Fever
(Bunyavirus and Arenavirus, respectively)
Genome:
Circular, ambisense RNA in 3 parts (small, medium, large)
Bunyavirus:
CCHF
Genome
Ambisense RNA in 2 strands (small and large)
Arenavirus
Lassa Fever
South American HF
LCMV
Where do arenaviruses get their name from?
Arena means “sand”
Virions are enveloped and have grainy appearance caused by ribosomes of the host cell
How do we get infected with arenaviruses?
Contact with rodent excreta (aerosol transmission)
Which group of people is Lassa Fever the most severe in?
Pregnant women (especially 3rd trimester = 95% mortality)
Most common complication of Lassa Fever
Deafness
Swollen Baby Syndrome
Think Lassa Fever
Give supportive care + Ribavirin
Big, brick-shaped
Complex capsid
dsDNA (linear)
Pox
Only DNA virus that replicates in the cytoplasm
Pox
Appearance of smallpox vs chickenpox
Smallpox is denser on extremities (including palms and soles) and face
Chickenpox is the opposite
Guarnieri bodies
Egg inoculation
Smallpox
No animal reservoir
1 serotype
Smallpox
Have to give vaccine with a bifurcated needle
Smallpox
Human Vaccinia Immune Globulin (hVIG)
Used to treat adverse rxns to the smallpox vaccine
MVA
Modified Vaccinia virus Ankara
Replaced older smallpox vaccine
Stockpiled in the U.S. in case of an outbreak
