Week 3: Infection and Disease

Question 1

What is a pandemic?

Answer 1

Affects the whole world

Question 2

What is an endemic?

Answer 2

Affects a whole community

Question 3

What is a case cluster?

Answer 3

Group of infections, usually connected to one event or

source

Question 4

What is an outbreak?

Answer 4

Colloquial term, sometimes applied to single cases of an

unusual disease

Question 5

What is an illness?

Answer 5

Subjective lack of well-being

Question 6

What is an infection?

Answer 6

Process resulting from encounter with biological agent

Question 7

What is a disease?

Answer 7

Collection of objective clinical features

Question 8

What is an microbe?

Answer 8

Living thing that cannot be seen without a microscope

Question 9

What are the 2 types of viruses?

Answer 9

DNA - Lack Ribosomes and RNA

RNA - Lack Ribosomes

Question 10

Rapidly spreading viruses are usually what type?

Answer 10

RNA viruses

Question 11

What is a virus?

Answer 11

Invasive (microscopic) biological agent that reproduces inside the cells of living hosts

Question 12

What are the components of a virus?

Answer 12

Genes (DNA / RNA) - makes it unique and tells it how tomultiply

Packaged in a protective protein capsid

May/not have envelope (mainly lipids, also proteins,
carbohydrates) surrounding capsid. Especially when virus outside of cell

May contain some essential enzymes for reproduction that may not be present in host cell

Question 13

What is a Virion?

Answer 13

A Virus particle

Question 14

Helical viruses can be _____ or ________. They hold __________ in their _________, _______ capsid

Answer 14

Rigid or Flexible

Nucleic Acid in their cylindrical and helical capsid

Question 15

Icosahedral viruses have ________ that assemble into __________________________________.

Answer 15

Capsomeres

20 equilateral triangular faces with twelve corners

Question 16

Most viruses are _______ in size and to see them we need ______________.

Answer 16

20-300nm

Electron microscopy

Question 17

Viruses can only reproduce ___________________.

Answer 17

Inside a living cell

Question 18

How do viruses enter the cells?

Answer 18

The must first attach to a receptor on the cell surface and if it is the proper host cell it will enter the cell

Question 19

What are the mechanisms of Viral Pathogenesis?

Answer 19

• Cell death or dysfunction of the cells they infect
• Immune mediated disease
• Modification of host immune responses
• Lymphoproliferative disease
• Malignant transformation

Question 20

What are serological tests for infectious agents used for?

Answer 20

Diagnose recent infection
Provide evidence of latent infection
Identify past infection
Determine “immunity”

Question 21

What is a prion?

Answer 21

Proteinaceous Infectious particles, it is not a virus or living organism. It causes spongiform encephalopathies (Large vacuoles in the brain)