Transcript H5N1 Avian Flu

Ryan Kang
Jeff Huynh
Per. 5
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Virus
Subtype H5N1 influenza
A strain
Usually unlikely to
transfer from birds to
humans
Human to Human
infection is inefficient
and unsustained.
Genus of
orthomyxoviridae family
of viruses.
Structure of RNA based influenza A
virus
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Flu symptoms: Fever, cough, sore throat, muscle
soreness
Optic infection, pneumonia, respiratory disease
Can result in death
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Retrovirus- single
negative-sense RNA
genome
10 genes in 8 RNA
segments that code for
the production of 11
different proteins.
Surface Hemagglutinin is
surface protein that
serves as spikes in
spherical virus structure
and attaches to sialic
acid receptors on cells of
humans and birds.
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The cell takes in virus and tranfsers
genetic information of virus as RNA
to bind to cellular pre- mRNA and
makes a readable copy of its genome.
The new readable mRNA is
translated by ribosomes into protein
structures.
PB2 section of RNA sequence in
H5N1 has a glutine at position 627
while most human influenza strains
have a lysine.
As proteins are synthesized by host
cell nucleus, new virions are made
and filled with the RNA to later infect
new cells and sent out into
extracellular fluid by lysogenesis:
viruses are cleaved out with parts of
cellular membrane aka exocytosis
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H5N1 may induce “cytokine
storm”.
The T cells of the body’s
immune system release
cytokines to tell body to
sneeze, produce heat,
produce more mucus.
Too much release of cytokine
will result in toxic shock-like
syndrome, inducing severe
symptoms of chills, fever,
headache, and can result in
death.
Another way to die from
H5N1 is disruption of the
lung’s epithelial cells.
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Treatments include antiviral drugs, rest, increased fluid consumption
Vaccines will provide natural immunity to virus, as antibodies will attach
to surface proteins of H5N1 virus. Current identification of such
antibodies are being researched as samples are being studied from bird flu
survivors.
New technologies as genetically- engineered mice to produce human
antibodies are showing promise for universal influenza vaccines.