2 - Pop. Epi. & Public Health Emergencies

Question 0

10 investigation steps in investigating an outbreak

Answer 0

1. Verify index case diagnosis
2. Determine extent
3. Establish outbreak
4. Decide priority
5. Describe epidemiology
6. Construct hypotheses
7. Test hypotheses
8. Institute controls
9. Report appropriately
10. Institute f/u surveillance

Question 1

List 6 factors that can lead to epidemics.

Answer 1

Increased virulence of an agent
Recent introduction of an agent into a susceptible population
Enhanced/unnatural mode of transmission -> more people exposed (aerosolizing agents, dirty bombs)
Change in susceptibility of the host response to the agent (immunosuppression)
Factors that increase host exposure
Public or media construction (misunderstanding of epidemiology)

Question 2

How can you verify a diagnosis in an index case? (2)

Answer 2

Collect specimens

Talk directly to heath care providers, etc

Question 3

How do you establish the extent of a potential outbreak? (2)

Answer 3

Call hospitals, schools, LTCFs, labs

Review surveillance systems

Question 4

How can you establish that an outbreak is actually occurring? (3)

Answer 4

Make sure cases are increased over baseline
Even ONE case can indicate problem (Ebola)
Beware of bias

Question 5

What priorities should be considered when evaluating an outbreak? (4)

Answer 5

How severe?
Is public concerned?
Are control measures available?
Are there resources available?

Question 6

What three characteristics should you use to describe outbreaks?

Answer 6

Person: demographics, activities
Time: incubation and duration of illness
Place: where do cases live, travel, congregate?

Question 7

What 5 questions should be considered when constructing a hypothesis?

Answer 7

What is the agent?
What is the source?
Mode of transmission?
What is the reservoir?
Who gets disease and who is still at risk?

Question 8

What two things should you do to test your hypothesis further?

Answer 8

Interview cases for risk factors

Perform an environmental investigation

Question 9

What factors should be considered in instituting controls? (3)

Answer 9

Protect susceptibles: remove from exposure, prophylaxis, vaccination
Remove source: food, ill people, water
Isolate and quarantine: isolate infected, quarantine exposed

Question 11

Differentiate isolation from quarantine.

Answer 11

Isolation: for people who are sick; put them somewhere they can’t infect others
Quarantine: for people who were exposed; cannot leave an area

Question 12

To where should you report the status/presence of an outbreak?

Answer 12

Report to NH DHHS

Question 13

(OBJ) Identify the main sources of data on health and disease in the US.

Answer 13

Census: population statistics

• -Mandated every 10 years
• -Collects data on everyone
• -Problems: undercounting, especially of young black males and the elderly; bad for intercensus year population changes

Vital Statistics/Certificates
–Cover births, deaths, marriages, and divorces

Morbidity Data Sources

1. Reports of notifiable diseases
2. Disease registers: for a particular disease of interest; can be population based or hospital based
3. Third party payers collect data to indicate use of medical care resources and frequency of certain conditions
4. National Health Survey: includes health interview survey, national health and nutrition examination survey, and national hospital discharge survey

Question 14

(OBJ) Describe age-adjusted rates and recognize when these measures are used appropriately.

Answer 14

FINISH

Question 15

(OBJ) Identify the leading causes of mortality and disability in the US for the entire population and for major subgroups of the population (male, female, children, young adults, elderly, black, white)

Answer 15

Male death rates greater than for females at all ages because of more frequent death by injury in early adulthood and more ischemic heart disease and cancer later

Children: injuries

Young adults: injuries (MVA, homicide, suicide); risk 3x greater for men and women; lots of homicide in black men

Elderly: cardiovascular diseases, cancer

Black: heart disease, cancer, stroke

White: heart disease, cancer, chronic lower respiratory disease

Disability: conditions of musculoskeletal system (arthritis), digestive diseases, mental illnesses

Question 16

(OBJ) Describe changes in the major causes of death over time.

Answer 16

Have changed from infectious diseases (pneumonia, TB, enteritis) to chronic, degenerative diseases (ischemic heart disease, cancer stroke)

Question 17

(OBJ) Contrast major indicators of health and disease in the developed countries with those in the less developed countries.

Answer 17

High birth rate
High infant mortality rate
High crude death rate
Low life expectancy
Young population, many under 15, few older than 65
Low literacy
Low per capita income
Many males engaged in agriculture
Diseases due to poor environmental conditions common
Low physician to population ratio

Question 18

(OBJ) Describe the importance of accurate death certification and disease reporting to public health, and where to find information on the process.

Answer 18

FINISH

Question 19

(OBJ) Define adjusted rate. Know how to calculate an age-specific rate.

Answer 19

A computed disease rate the takes into account the characteristics of the population so that rates in different locales can be compared despite differences in these characteristics

Typical adjustment factors: age, gender

Question 20

Define attack rate. Give an example.

Answer 20

The incidence of disease occurring during a limited period of risk
–Ex. the time span of a food borne outbreak of gastroenteritis

Question 21

(OBJ) Define case-fatality.

Answer 21

The proportion (%) of people with a disease who die within a specified time after disease onset

Question 22

(OBJ) Define crude rate.

Answer 22

A disease rate the includes all person in a population without distinction with regard to age, gender, race, etc.

Question 23

Define disease register.

Answer 23

A database of information regarding all cases of certain diseases that occur in a specified population during a specified time period
–Ex. state [population-based] or hospital cancer registries

Question 24

(OBJ) Define incidence rate.

Answer 24

The rate of development of new cases of a disease
Usually expressed as cases per thousand person years
[Contrast with prevalence]

Question 25

(OBJ) Define infant mortality rate.

Answer 25

The number of deaths of children under 12 months old in a given year divided by the total number of live births in that year, times 1000

Question 26

Define maternal mortality rate.

Answer 26

The number of deaths related to pregnancy of pregnant women in a year divided by the number of live births in that year, times 100,000

Question 27

(OBJ) Define mortality rate.

Answer 27

The incidence rate of death

Question 28

(OBJ) Define neonatal mortality rate.

Answer 28

The number of deaths of children under 28 days old in a given year divided by the total number of live births in that year, times 1000

Question 29

Define notifiable disease.

Answer 29

A disease for which notification of local (usually state) health authorities is required

Question 30

Define perinatal mortality rate.

Answer 30

The number of fetal deaths occurring 28 weeks or later in a pregnancy plus deaths in the first week of life divided by the number of live births and fetal deaths 28 weeks or more in that year, times 1000

Question 31

(OBJ) Define prevalence.

Answer 31

The proportion of a population that has a disease (or a trait) at some point in time
[Contrast with incidence]

Question 32

Define secondary attack rate.

Answer 32

The incidence of disease among contacts or household members following the occurrence of a primary case
Period of observation is specified, usually brief

Question 33

Define specific rate.

Answer 33

A disease rate for a specific sub-population of individuals

Question 34

Define third party payer.

Answer 34

A health insurance provider