Epi Chp 2

Question 0

List examples of direct transmission

Answer 0

A disease that can be transmitted person-to-person (direct transmission) by means of direct contact

Question 1

List the modes of disease transmission

Answer 1

Direct or in direct

Question 2

Explain indirect transmission

Answer 2

Indirect transmission can occur through a common vehicle such as a contaminated air or water supply, or a vector such as a mosquito.

Question 3

What are the three categories of factors that may be associated with increased risk of human disease?

Answer 3

Host characteristics

Types of agents and examples

Environmental factors

Question 4

Give examples of host characteristics that may be associated with increased risk of human disease

Answer 4

Age, sex, religion, race, customs, occupation, genetic profile, marital status, family background, previous disease, immune status

Question 5

List types of agents and examples that are associated with increased risk of disease

Answer 5

Biological-bacteria, viruses

Chemical-poison, alcohol, smoke

Physical - trauma, radiation, fire

Nutritional-lack, excess

Question 6

List environmental factors associated with increased risk of disease

Answer 6

Temperature, humidity, altitude, crowding, housing, neighborhood, water, milk, food, radiation, air pollution, noise

Question 7

Transmission of disease is determined by what 3 things?

Answer 7

Agent
Host
Environmental factors

Question 8

PH interventions are directed at ….?

Answer 8

Controlling or eliminating agent at source of transmission

Protecting portals of entry

Increasing host’s defenses

Question 9

Explain herd immunity

Answer 9

thresholds that stop disease transmission for selected vaccine preventable diseases.
(the percent of the population that has to be vaccinated to allow for herd immunity differs per disease but overall –high 80%-high 90% )

Question 10

explain why trends for food borne disease outbreaks have increased over the years.

Answer 10

increase in eating out

increased globalizations

increase in raw foods or organic foods

Question 11

What are the different kinds/classifications of food borne outbreaks

Answer 11

Poison, Bacterial - staph aureus

Infections, Bacterial - salmonella

Viruses - Hep A

Parasites - trichinosis

Plants - mushrooms

Chemical - arsenic, lead, methyl mercury in Japan (Minamata disease- food chain)

Food Additives - carrageenan, mycoprotein

Question 12

List the symptoms of food poisoning.

Answer 12

Nausea and vomiting

general weakness

abdominal pain/cramping

diarrhea

fever

Question 13

What is the importance of an epidemic curve?

Answer 13

Incubation period

Time- probable time period people were exposed

Time trend - whether outbreak was time limited or is ongoing, time frame of the epidemic

Pattern of disease spread - the probable mode of transmission

Magnitude of disease - how many are affected

Question 14

The overall shape of an epidemic curve may reveal what?

Answer 14

Common source - continuous or intermittent exposure

Point source

Propagated

Question 15

what is the formula for determining the Attack rate?

Answer 15

of people who ate a food and became ill / # people who ate that same food

Question 16

What are the three critical variables in investigating an outbreak or an epidemic?

Answer 16

when did the exposure take place

when did the disease begin

what was the incubation period for the disease

Question 17

Give the formula for determining attack rate

Answer 17

Number of people at risk in whom a certain illness develops
_________________________________
The total number of people at risk

Question 18

What formula is useful for comparing the risk of disease in groups with different exposures?

Answer 18

Attack rate

Question 19

When trying to determine food specific attack rate what formula should be used?

Answer 19

Total number of people who ate that food

Question 20

A person who acquires a disease from exposure (e.g. contaminated food) is called what?

Answer 20

Primary case

Question 21

Define secondary case?

Answer 21

A person who acquires the disease from exposure to a primary case

Question 22

The attack rate in susceptible people who have been exposed to a primary case are defined as ?

Answer 22

Secondary attack rate

Question 23

When a disease appears to have occurred at more than an endemic level and we wish to investigate its occurrence we ask what three questions?

Answer 23

WHO was attacked by the disease

WHEN did the disease occur

WHERE did the cases arise

Question 24

When confronted with several possible causal agents as is often the case in foodborne disease outbreaks, very helpful method for determining which of the possible agency is likely to be the cause is called?

Answer 24

Cross tabulation