2. Viral Cellular Pathogenesis
Pathogenesis is the result of the complex interactions that the virus undergoes
when it uses the biosynthetic machinery of the cell for replication and when it is
exposed to the defence mechanisms of the host
3. Viral Cellular Pathogenesis
Cells can respond to viral infections in 3 ways:
No apparent change
Death
Transformation
1.
2.
3.
Direct cell damage and death from viral infection may result from :
Indirect cell damage can result from :
Diversion of the cell's energy, shut off of cell macromolecular synthesis,
competition of viral mRNA for cellular ribosomes, competition of viral promoters
and transcriptional enhancer for cellular transcriptional factor such as RNA
polymerase, and inhibition of the interferon defense mechanisms.
integration of the viral genome, induction of mutations in the host genome,
inflammation, host immune response.
4. Pathogenicity
of Avian Influenza
Virus (AI)
High Pathogenic Avian Influenza
LPAI
HPAI
Low Pathogenic Avian Influenza
The Prime
Determinant ?
HA (hemagglutinin)
5. Structure of Avian
Influenza Virus
HA initiates
infection
by binding to cell
surface receptors
by inducing membrane
fusion
