Filoviridae Flashcards
What type of virus is filoviridae?
Negative sense SS RNA
enveloped
What are the virus of filoviridae?
ebola
marburg
what are the identifiable species ebola?
Zaire Sudan Taï Forest (Côte d’Ivoire) Bundibugyo Reston (non human primates)
What are the similarities and differences between arburg AND EBOLA?
Genetic differences Clinically very similar Ebola: 50-85% mortality Marburg: 25% mortality Epidemiologically vary similar
What type of Nucleocapsid is Filovoridae?
Helical with central hollow cavity which surrounds RNA
What are the parts of the filoviridae?
Envelope
nucleocapsid
glycoprotein
RNA dependent RNA polymerase
What is the function of the Glycoprotein
Forms spikes on the outer surface of the virion; it mediates attachment and entry into the host cell. The gene for this protein is now being used inEbola vaccine developmentand clinical trials are underway.
How does Filovirdae replicate?
in the cytoplasma using a RNA dependent RNA polymerase
What are the steps in replication of Filoviradae?
Attachment of virus to cell. Glycoprotein attaches to several receptors.
2-4. Uncoating and escape from endosome.
5. Nucleocapsid released into cytoplasm and is replicated.
6. Viral genome is transcribed into mRNA
7. Further – strands are generated to become genomes of the progeny virions
7. Translation to create proteins
8. Glycoprotein is synthesized and modified in the ER and golgi
9. GP delivered to the plasma membraneWhat are the steps in replication of
10. The virus is assembled and buds from the surface.
What is the pathogenesis of filoviridae?
Entry: Mucous membranes or break in skin
Invasion: Multiple cell types (mostly macrophages and dendritic cells)
Spread: site of inoculation to regional lymph nodes, then liver, spleen, and other lymphoid tissues (cellular destruction)
systemic inflammation (Vascular leakage and multi-organ failure, May cause GI symptoms)
Coagulation defects ( caused by host immune system)
impairment of adaptive immune system (Virus replicates within DC’s and other immune cells—destroys them.
Survivors are immune to reinfection)
Sepsis due to bacterial leakage from the gut
What are the initial symptoms of ebola?
fever intense weakness headache sore throat Joint and muscle pain
What are symptoms of ebola followed by which symptoms?
vomiting stomach pain diarrhea rash impaired kidney and liver function
What are symptoms seen in some patients of ebola?
internal & external bleeding
red eyes
hiccups
rash
What is a major reservoir of ebola?
transmitted through bats
How can ebola be transmitted?
close contact with a person who has ebola or who has died from ebola
touching blood or bodily fluids from an infected person
using needles of an ebola patient
handling infected animals or bodily fluids of infected animals
