Disease Populations

Question 1

What is MSY?

Answer 1

Maximum sustainable harvest that can occur without decreasing the population growth rate

Question 2

What is considered a disease?

Answer 2

An atypical condition in a living organism that causes some sort of physiological impairment

Question 3

What can disease be caused by?

Answer 3

Genetic abnormalities
Exposure to toxins
Interactions with organisms

Question 4

What are all disease-causing organisms?

Answer 4

Selfish

Question 5

What is direct transmission?

Answer 5

Direct, physical transfer of the infectious agent
-touching sick person

Question 6

What is indirect transmission?

Answer 6

Indirect transfer of the infectious agent
-airborne, fomites, animal vectors

Question 7

What is horizontal transmission?

Answer 7

Among individuals of the same generation

Question 8

What is vertical transmission?

Answer 8

From mother to child before or during birth

Question 9

How do viruses replicate?

Answer 9

Virus binds to and enters cells
Delivers its genome to a site where it can produce new copies of viral proteins and RNA
Viral proteins and RNA assemble into new viral particles and exist the host cell via the cell wall bursting

Question 10

Example of horizontally transmitted diseases

Answer 10

Influenza

Question 11

Example of vertically and horizontally transmitted diseases

Answer 11

HIV
Chickenpox
Zika
Microcephaly

Question 12

What is an endemic?

Answer 12

Constant presence but relatively low spread

Question 13

What is an epidemic?

Answer 13

Sudden increase (spreading) in certain regions

Question 14

What is a pandemic?

Answer 14

Global epidemic

Question 15

What is epidemiology?

Answer 15

Science that studies the population dynamics and consequences of pathogenic diseases
R0 is basic reproduction number

Question 16

Why can’t we construct a life table and fecundity schedule for pathogens?

Answer 16

They are microscopic
Pathogen success must be measured in terms of their host behaviour and pathogen traits

Question 17

What is the interpretation of R0?

Answer 17

Average number of susceptible people that will be infected by a person with a disease in a naive population without transmission interventions

Question 18

What can the basic reproduction number inform us of?

Answer 18

How easily a disease spreads and how difficult it is to contain a disease
Does not reveal virulence

Question 19

What are compartment models used for?

Answer 19

Understanding how to stop the spread of diseases

Question 20

What are compartments?

Answer 20

Subpopulations of the host

Question 21

What do arrows in a compartment model represent?

Answer 21

Individuals leaving one subpopulation and entering another one
Letters next to arrows show the per capita rate of contribution/transition

Question 22

What is isolation?

Answer 22

Separate sick individuals from healthy individuals

Question 23

What is a quarantine?

Answer 23

Separate individuals who have been exposed to the illness, even if they are not presenting any symptoms

Question 24

How can we slow a disease?

Answer 24

Behavioural change
Herd immunity

Question 25

What is herd immunity?

Answer 25

Occurs when immunity rates are high enough that the population growth rate of the pathogen is negative and may go extinct

Question 26

What is the herd immunity threshold (H)?

Answer 26

Min % of population that needs to be immunized to reach heard immunity

Question 27

What do highly contagious pathogens have?

Answer 27

Have higher herd immunity threshold because they spread fast

Question 28

What are diseases with high transmission rates hard to eradicate?

Answer 28

They have high population growth rates, hard to achieve herd immunity