BIOL 437 Week Two Part 1

Question 1

disease

Answer 1

-an interpretation or disorder of body functions, systems or organs

Question 2

diseases arise from

Answer 2

• infectious agents (pathogens)
• inherent weaknesses
• environmental stresses

Question 3

environment

Answer 3

• all that is external to the human host

- physical, social, biological, cultural

Question 4

‘random’ occurrence of disease

Answer 4

-do not occur randomly

>some individuals are more at risk as risk factors are not randomly distributed in the population

Question 5

epidemiologic triad/triangle

Answer 5

1. Agent
2. Susceptible host
3. Environment (now has a major influence)
   * simplest model of disease causation

Question 6

agent

Answer 6

• infectious micro-organism/pathogen

- toxins, physical forces

Question 7

chronic diseases with multiple causes

Answer 7

• triad model does not work well

eg. CVD, cancer

Question 8

infectious microorganisms/pathogen

Answer 8

• virus, parasite, bacterium

- necessary, but not necessarily sufficient alone (ex. dose, pathogenicity)

Question 9

host

Answer 9

-human or animal who can get the disease

Question 10

risk factors influences

Answer 10

• exposure
• susceptibility
• response to agent

Question 11

examples of risk factors

Answer 11

• behaviours
• hygiene
• psychological makeup
• medications
• gender
• age
• genetics
• nutrition
• immune status
• comorbidity

Question 12

environment

Answer 12

-factors affecting the agent and the opportunity for exposure

Question 13

examples of environment

Answer 13

• geology
• climate
• socioeconomic factors
• biologic factors (insect vectors)

Question 14

socioeconomic factors

Answer 14

• crowding
• sanitation
• access to health care

Question 15

primary focus in epidemiology

Answer 15

• identifying the causes of disease

- identify mechanisms by which disease spread

Question 16

etiology

Answer 16

-science and study of the causes of disease and their mode of operation

Question 17

communicability

Answer 17

-ability of a disease to be transmitted from one person to another or to spread through the population

Question 18

classify acute and chronic disease according to

Answer 18

• infectivity

- communicability

Question 19

communicable disease

Answer 19

-when an infectious disease is contagious or capable of being communicated or transmitted

Question 20

examples of communicable diseases

Answer 20

• HIV/AIDS
• cholera
• influenza
• cryptosporidiosis

Question 21

vertical transmission

Answer 21

-transmission from an individual to its offspring through sperm, placenta, milk or vaginal

Question 22

horizontal transmission

Answer 22

-transmission of infectious agents from an infected individual to a susceptible peer

Question 23

pathogens

Answer 23

-organisms or substances such as prions, bacteria, viruses, fungi, or parasites that are capable of producing diseases

Question 24

invasiveness

Answer 24

-the ability to get into a susceptible host and cause diseases

Question 25

virulence

Answer 25

-the disease-evoking power of a pathogen

Question 26

toxins

Answer 26

-kill pathogens by poisoning them

Question 27

antibiotics

Answer 27

• work against pathogens because of their toxicity

- using bacteria to fight off other bacteria and pathogens

Question 28

acute

Answer 28

• disorder with sudden onset
• relatively severe
• short duration of symptoms

Question 29

chronic

Answer 29

• less severe
• long and continuous duration
• lasting over long periods, if not a lifetime

Question 30

natural history and spectrum of disease

Answer 30

• progression of disease in a person over time without treatment
• most diseases have a characteristic natural history
• appropriate exposure to accumulation of factors sufficient for the disease to start in a susceptible host

Question 31

major stages in the disease process

Answer 31

1. Susceptibility
2. Pre-symptomatic disease
3. Clinical disease
4. Recovery, disability, or death

Question 32

pre-symptomatic disease stage

Answer 32

• incubation period

- latency period

Question 33

susceptible host factors

Answer 33

• genetics
• specific immunity
• non-specific defences
• malnutrition
• alcoholism
• concurrent disease: comorbidities