Section 9

Question 1

Define epidemiology

Answer 1

Occurrence, spread, and control of diseases

Question 2

Epidemiology is concerned with ____ rather than _____

Answer 2

Populations, individuals

Question 3

Define infection

Answer 3

Presence of a infectious organism in an individual or population

Question 4

Define disease

Answer 4

Detectable clinical consequence of infection

Question 5

Define incubation time

Answer 5

Time interval between exposure to infection and appearance of disease

Question 6

What does a longer incubation time mean?

Answer 6

Infection is harder to control because infected individual can spread it to more people unknowingly

Question 7

Define infectious

Answer 7

Infected person capable of transmitting infection to others

Question 8

What does infectiousness depend on?

Answer 8

• Infectious agent
• Environment
• Characteristics of the individuals in the population

Question 9

Define transmission

Answer 9

Spread of infection

Question 10

Define symptoms

Answer 10

What the patient feels

Question 11

Are symptoms subjective or objective?

Answer 11

Subjective

Question 12

Are signs subjective or objective?

Answer 12

Objective

Question 13

How can signs be measured?

Answer 13

Through direct observation

Question 14

Define prevalence

Answer 14

Number of existing cases in a population at a given point in time

Question 15

Define incidence

Answer 15

Number of new cases occurring in a population during a specific time period

Question 16

Define communicable

Answer 16

Spread from one individual to another

Question 17

Give an example of direct and indirect spread

Answer 17

• Direct = touch

- Indirect = vector

Question 18

Define contagious

Answer 18

Easily spread

Question 19

Define non-communicable

Answer 19

Not spread through individuals

Question 20

What occurs in the incubation period?

Answer 20

• Cells are multiplying/dividing

- Person is capable of spreading the pathogen

Question 21

In which periods are we most concerned about spread of infections?

Answer 21

Latent, infectious, incubation, and symptomatic

Question 22

Define endemic

Answer 22

Stays at low level and reappears every year

Question 23

What is an example of an endemic in Canada?

Answer 23

Pertussis

Question 24

Define sporadic

Answer 24

Disease becomes present that is not normally found in an area

Question 25

What is an example of a sporadic disease in Canada?

Answer 25

Cholera

Question 26

Define pandemic

Answer 26

Epidemic that spreads over at least 2 continents

Question 27

What is an example of a pandemic?

Answer 27

Zika, ebola

Question 28

Define acute disease

Answer 28

Rapidly developing with a short duration

Question 29

What is an example of an acute disease?

Answer 29

Influenza

Question 30

Define chronic disease

Answer 30

Slow to develop with continual duration

Question 31

What is an example of a chronic disease?

Answer 31

Tuberculosis

Question 32

What do cross-sectional studies measure?

Answer 32

The frequency of an outcome and/or exposure in a defined population at a particular point in time

Question 33

Is exposure or outcome determined first in a cross-sectional study?

Answer 33

Determined at the same time

Question 34

What is the problem with cross-sectional studies?

Answer 34

Don't know if the exposure preceded the outcome

Question 35

What does with exposure, without outcome mean?

Answer 35

Person is exposed to the pathogen but doesn't show signs and symptoms

Question 36

What happens in a case-control study?

Answer 36

Cases (with the outcome) and controls (without the outcome) are identified and their exposure status is determined

Question 37

What happens in a cohort study?

Answer 37

Individuals with and without exposure are identified and followed until they develop the outcome or until the study ends

Question 38

What evidence does a cohort study provide?

Answer 38

That an association between disease and exposure is causal

Question 39

Which 2 viruses cause Kaposi sarcoma?

Answer 39

HHV and HIV

Question 40

Is a cohort study done over a short or a long period of time?

Answer 40

Long

Question 41

What is the problem with cohort studies?

Answer 41

Control of outside sources

Question 42

What happens in intervention studies?

Answer 42

Individuals are allocated an intervention and are followed until they develop the outcome or until the study ends

Question 43

What are double-blinded trials?

Answer 43

When neither the investigator nor participant knows who receives the active intervention and who receives the placebo

Question 44

What is one challenge with widespread outbreaks?

Answer 44

Hard to determine origin

Question 45

Define epidemic

Answer 45

A disease grows in numbers in a widespread area (numbers are much higher than normal)