Chapter 16- Epidemiology

Question 1

Epidemiology

Answer 1

The study of factors influencing the frequency and distribution of diseases

Question 2

What do epidemiologists do?

Answer 2

collect, compile data about sources of disease and risk factors

Question 3

Communicable diseases

Answer 3

Transmitted from one host to another with different degrees of contagiousness (ex. measles, colds, influenza)

Question 4

Non communicable diseases

Answer 4

do not spread from host to host (ex, legionella pneumophila)

Question 5

Attack rate

Answer 5

percentage of people who become i’ll in population after exposure to infectious agent

Question 6

Incidence

Answer 6

number of new cases/time/population
-measure of risk of an individual contracting a disease

Question 7

prevalence

Answer 7

total number of cases at any time or for a specific period in a given population

Question 8

morbidity

Answer 8

incidence of disease in a population

Question 9

Mortality

Answer 9

overall death rate in population

Question 10

Case-fatality rate

Answer 10

percentage of population that died from a specific disease

Question 11

Endemic disease

Answer 11

constantly present in population

Question 12

Sporadic

Answer 12

unusually large number of cases

Question 13

Outbreak

Answer 13

group of cases at specific time and population

Question 14

pandemic

Answer 14

global

Question 15

Fomites

Answer 15

non living objects that facilitate the indirect transmission of pathogens

Question 16

Chain of infection

Answer 16

Reservoir of infectious agent-portal of exit-transmission-portal of entry-susceptible host

Question 17

Reservoir of infection

Answer 17

natural habitat of pathogen-living/nonliving, in or on animal, human, or environment

Question 18

Symptomatic infections

Answer 18

clear source of pathogens, disease may be spread before symptoms appear or after they go away

Question 19

Asymptomatic infections

Answer 19

harder to identify, carriers may not notice infection, can spread it to others

Question 20

Portal of exit

Answer 20

body surface or orifice: exit route for pathogen
(ex. intestinal tract (e.coli) respiratory tract, skin, genitalia pathogens)

Question 21

V. cholerae

Answer 21

intestinal tract organisms exit in the feces, watery diarrhea

Question 22

S. aureus

Answer 22

shed on skin cells

Question 23

Vertical transmission

Answer 23

pregnant woman to fetus or mother to infant during childbirth, breast feed

Question 24

Horizontal transmission

Answer 24

person to person via air, physical contact, ingestion of food or water, or vector

Question 25

Direct transmission

Answer 25

involves immediate transfer or infectious agent to portal of entry

Question 26

Direct contact

Answer 26

touch, handshake, sexual intercourse

Question 27

Vehicle transmission

Answer 27

transmission of pathogens via water, food, air (tainted food)

Question 28

Indirect transmission

Answer 28

several ways: airborne, vehicle borne(transmitted by objects, food, water), fomites

Question 29

Mechanical vector (indirect)

Answer 29

carrie’s microbe on its body from one location to another

Question 30

Biological vector (indirect)

Answer 30

participates in life cycle of pathogen

Question 31

Vector

Answer 31

living organism that can carry pathogen

Question 32

Portal of entry

Answer 32

body surface or orifice: entry route for pathogen

Question 33

Virulence

Answer 33

ability to cause disease

Question 34

Dose

Answer 34

number of pathogens introduced; minimum number of pathogens required to produce symptoms

Question 35

incubation period

Answer 35

influences extent of spread

Question 36

Population characteristics that influence epidemiology of disease

Answer 36

immunity general health age gender religious practices genetic background

Question 37

Descriptive studies

Answer 37

define characteristics of disease outbreak, person/place/time

Question 38

Analytical studies

Answer 38

more detailed/analyze, determines risk factors relevant to spread of disease

Question 39

Experimental studies

Answer 39

Trying different treatments, often used to test effectives of a specific treatment

Question 40

CDC

Answer 40

provides support for infectious disease laboratories in the US

Question 41

WHO

Answer 41

1. Provide worldwide guidance in field of health 2. Set global standards for health 3. Cooperatively strengthen national health programs 4. Develop and transfer appropriate health technology

Question 42

Reduction/eradication of disease

Answer 42

Reduction through sanitation, vector control, vaccination, abx (ex. smallpox, measles, polio)

Question 43

Emerging disease

Answer 43

novel or have recently increased in incidence (ex. covid, ebola)

Question 44

Factors that contribute to emergence/reemergence

Answer 44

Microbial evolution Complacency Behavioral changes Technology Population expansion Development Food distribution and importation War and civil unrest Climate changes

Question 45

HAI’s (Healthcare associates infections)

Answer 45

acquired while receiving treatment in a healthcare setting (ex. C. diff, E. coli, Pseudomonas, S.aureus, surgical site infections, GI infections)

Question 46

HAI transmission

Answer 46

other patients, healthcare environment, workers, visitors, medical devices