Vet Viral Diseases

Question 1

What does a virus consist of?

Answer 1

nucleic acid that is enveloped by a protein coat

Question 2

What does a virus require for replication/survival?

Answer 2

To invade a host cell

Question 3

Example of a viral replication process (equine influenza)

Answer 3

• attachment
  -fusion of viral envelope
  -uncoating
  -assembly of nucleocapsids
  -protein synthesis
  -replication of DNA
  -Transport vesicle
  -Release

Question 4

What are the mortality rates of viruses?

Answer 4

some of the highest percentages

Question 5

What key immune responses occur due to a virus?

Answer 5

• CD8 lymphocytes
  -Antibodies
• Nk cells
  -Type 1 interferons

Question 6

What do type 1 interferons do?

Answer 6

• key-early anti viral response
  -produced by virally infected cells within hours
  -not detectable until 5-6 days
  -upregulate MHC class 1
  -degradation of dsRNA

Question 7

What are the main causes of increased variation in viruses?

Answer 7

• mutation
• recombination
  -reassortment

Question 8

What types of viruses are there?

Answer 8

• DNA
• RNA

Question 9

Which type of virus undergoes reassortment and which undergoes recombination?

Answer 9

Reassortment = RNA
Recombination = DNA

Question 10

What is immune evasion?

Answer 10

Deliberate modulation of a host immune system to benefit the infectious agent

Question 11

What types of modulation is there during viral immune evasion?

Answer 11

• prevent detection
• preventing signals
• faslifying signals
• false targets

Question 12

How do you avoid viral immune evasion?

Answer 12

• vaccination
• target key protein involved in immune evasion or virulence and deliberately cause deletion