Module 2

Question 1

TRUE or FALSE:
Viral infection is always synonymous with disease.

Answer 1

FALSE

Question 2

TRUE or FALSE:
There are some subclinical viral infections

Answer 2

TRUE

Question 3

Used as a quantitative or relative measure of the pathogenicity of the infecting virus

Answer 3

Virulence

Question 4

TRUE or FALSE:
For viruses to cause disease, they must only have to infect and spread within the host

Answer 4

FALSE

Question 5

TRUE or FALSE:
Viruses differ greatly in their virulence.

Answer 5

TRUE

Question 6

TRUE or FALSE:
There are no differences in the outcome of infection between individual animals.

Answer 6

FALSE

Question 7

TRUE or FALSE:
Variation amongst viruses of the same species and the determinants of viral virulence are often multifactorial

Answer 7

FALSE; is often MULTIGENIC

Question 8

TRUE or FALSE: Determinants of host resistance/susceptibility are multifactorial

Answer 8

TRUE

Question 9

Quantitative or Qualitative:
Rate/yield of the virus replication

Answer 9

Quantitative

Question 10

Quantitative or Qualitative:
Lethal dose

Answer 10

Quantitative

Question 11

Quantitative or Qualitative:
Infectious dose

Answer 11

Quantitative

Question 12

Quantitative or Qualitative:
Number of cells infected in an organ

Answer 12

Quantitative

Question 13

Quantitative or Qualitative:
Organ or tissue tropism

Answer 13

Qualitative

Question 14

Quantitative or Qualitative:
Extent of host-cell damage

Answer 14

Qualitative

Question 15

Quantitative or Qualitative:
Mode and efficacy of spread in the body

Answer 15

Qualitative

Question 16

Quantitative or Qualitative:
Character of the disease they induce

Answer 16

Qualitative

Question 17

The dose of the virus required to cause death in 50% of animals.

Answer 17

Lethal dose 50

Question 18

Ratio of the dose of a virus that causes infection in 50% of
individuals.

Answer 18

Infectious dose 50

Question 19

What has facilitated the determination of the genetic basis of virulence of many viruses.

Answer 19

Molecular biology

Question 20

What identified the role of potential determinants of virulence

Answer 20

Genetic Sequence Comparison

Question 21

TRUE or FALSE:
Viral infections tend to be more pathogenic in their natural host species than in exotic or introduced species.

Answer 21

FALSE

Question 22

What is the fundamental determinant of host resistance/susceptibility to particular virus.

Answer 22

Expression of critical receptors on target cells

Question 23

TRUE or FALSE:
More conserved receptors leads to a narrower host range

Answer 23

FALSE

Question 24

Changes in viral attachment can lead to what?

Answer 24

Emergence of variant viruses

Question 25

What protects the respiratory tract; consists of a layer of mucus produced by goblet cells.

Answer 25

Mucociliary blanket

Question 26

TRUE or FALSE: Small particles are trapped on the mucociliary blanket lining nasal cavity and airways.

Answer 26

FALSE

Question 27

TRUE or FALSE: Smaller particles are directly inhaled into the airspaces of the lungs

Answer 27

TRUE

Question 28

What are the different defenses protecting the gastrointestinal tract

Answer 28

1. Acidity of the stomach. 2. Layer of mucus. 3. Antimicrobial activity of digestive enzymes. 4. Bile and pancreatic secretions. 5. Innate and adaptive immune mechanisms

Question 29

Enteric infections by certain viruses first infect the?

Answer 29

Epithelial cell lining of the GI mucosa and the Specialized M cells of Peyer's pathces

Question 30

In the skin there are presence of migratory dendritic cells called

Answer 30

Langerhans cells

Question 31

TRUE or FALSE: Viral infection can remain confined to the skin

Answer 31

TRUE

Question 32

These are viruses that are both transmitted by and replicate in arthropod vectors

Answer 32

Arboviruses

Question 33

Introduction of a virus by skin penetration that is a result of veterinary or husbandry procedures.

Answer 33

Latrogenic

Question 34

Refers to a viral infection that remains confined to the initial site of entry, only affecting nearby cells

Answer 34

Local Spread

Question 35

Refers to a viral infection indicating a systemic infection where the virus enters the bloodstream and can spread throughout the body to different organs

Answer 35

Viremic Spread

Question 36

A Family of virus that have glycoproteins (hemagglutinin) necessary for binding with specific receptors that allows their entry to cells.

Answer 36

Orthomyxoviruses

Question 37

Abnormal structures that form in the nucleus or cytoplasm of a host cell during a viral infection

Answer 37

Inclusion bodies

Question 38

They are made up of viral proteins and are a result of the viral multiplication process.

Answer 38

Inclusion bodies

Question 39

Spherical inclusions in nerve cells that are a sign of rabies infection.

Answer 39

Negri bodies