Module 2 Flashcards
TRUE or FALSE:
Viral infection is always synonymous with disease.
FALSE
TRUE or FALSE:
There are some subclinical viral infections
TRUE
Used as a quantitative or relative measure of the pathogenicity of the infecting virus
Virulence
TRUE or FALSE:
For viruses to cause disease, they must only have to infect and spread within the host
FALSE
TRUE or FALSE:
Viruses differ greatly in their virulence.
TRUE
TRUE or FALSE:
There are no differences in the outcome of infection between individual animals.
FALSE
TRUE or FALSE:
Variation amongst viruses of the same species and the determinants of viral virulence are often multifactorial
FALSE; is often MULTIGENIC
TRUE or FALSE: Determinants of host resistance/susceptibility are multifactorial
TRUE
Quantitative or Qualitative:
Rate/yield of the virus replication
Quantitative
Quantitative or Qualitative:
Lethal dose
Quantitative
Quantitative or Qualitative:
Infectious dose
Quantitative
Quantitative or Qualitative:
Number of cells infected in an organ
Quantitative
Quantitative or Qualitative:
Organ or tissue tropism
Qualitative
Quantitative or Qualitative:
Extent of host-cell damage
Qualitative
Quantitative or Qualitative:
Mode and efficacy of spread in the body
Qualitative
Quantitative or Qualitative:
Character of the disease they induce
Qualitative
The dose of the virus required to cause death in 50% of animals.
Lethal dose 50
Ratio of the dose of a virus that causes infection in 50% of
individuals.
Infectious dose 50
What has facilitated the determination of the genetic basis of virulence of many viruses.
Molecular biology
What identified the role of potential determinants of virulence
Genetic Sequence Comparison
TRUE or FALSE:
Viral infections tend to be more pathogenic in their natural host species than in exotic or introduced species.
FALSE
What is the fundamental determinant of host resistance/susceptibility to particular virus.
Expression of critical receptors on target cells
TRUE or FALSE:
More conserved receptors leads to a narrower host range
FALSE
Changes in viral attachment can lead to what?
Emergence of variant viruses
What protects the respiratory tract; consists of a layer of mucus produced by
goblet cells.
Mucociliary blanket
TRUE or FALSE:
Small particles are trapped on the mucociliary blanket lining nasal cavity and airways.
FALSE
TRUE or FALSE:
Smaller particles are directly inhaled into the airspaces of the lungs
TRUE
What are the different defenses protecting the gastrointestinal tract
- Acidity of the stomach.
- Layer of mucus.
- Antimicrobial activity of digestive enzymes.
- Bile and pancreatic secretions.
- Innate and adaptive immune mechanisms
Enteric infections by certain viruses first infect the?
Epithelial cell lining of the GI mucosa and the Specialized M cells of Peyer’s pathces
In the skin there are presence of migratory dendritic cells called
Langerhans cells
TRUE or FALSE:
Viral infection can remain confined to the skin
TRUE
These are viruses that are both transmitted by and replicate in arthropod vectors
Arboviruses
Introduction of a virus by skin penetration that is a result of veterinary or
husbandry procedures.
Latrogenic
Refers to a viral infection that remains confined to the initial site of entry, only affecting nearby cells
Local Spread
Refers to a viral infection indicating a systemic infection where the virus enters the bloodstream and can spread throughout the body to different organs
Viremic Spread
A Family of virus that have glycoproteins (hemagglutinin) necessary for binding with specific
receptors that allows their entry to cells.
Orthomyxoviruses
Abnormal structures that form in the nucleus or cytoplasm of a host cell during a viral infection
Inclusion bodies
They are made up of viral proteins and are a result of the viral multiplication process.
Inclusion bodies
Spherical inclusions in nerve cells that are a sign of rabies infection.
Negri bodies
