L21-23-Epidemiology (32.1-32.5 + lectures)

Question 1

Define epidemiology.

Answer 1

Study of the occurrence, distribution, and determinants of health and disease in a population. It deals with public health, the health of the population as a whole.

Question 2

Differentiate between endemic, epidemic, and pandemic disease.

Answer 2

-Endemic: disease is constantly present (usually low incidence) in a population
-Epidemic: simultaneously infects an unusually high number of individuals in a population
Pandemic: widespread (global) epidemic

Question 3

Differentiate between incidence and prevalence.

Answer 3

incidence: # of new cases (in a population in a given time)
prevalence: total # of new and existing disease cases (in a pop in a given time period)

Question 4

Differentiate between mortality and morbidity.

Answer 4

• mortality: incidence of death in a pop

- morbidity: incidence of disease in pop includes both fatal and nonfatal disease

Question 5

Differentiate: reservoir and carrier.

Answer 5

• reservoir: sites in which infectious agents remain viable and from which individuals may become infected, animate or inanimate
• carrier: a pathogen-infected individual who has a subclinical infection/shows no/mild symptoms of clinical disease. incubation or recovery period. (acute or chronic) (see defn. of transmission)

Question 6

Define: zoonosis.

Answer 6

A disease that primarily infects animals but is occasionally transmitted to humans

Question 7

Define: transmission.

Answer 7

Passing of a communicable disease from infected host individual/group to conspecific individual/group. 2 types-direct and indirect (through living/vector or inanimate/fomite carrier)

Question 8

Describe: herd immunity.

Answer 8

The resistance of a group to a pathogen as a result of the immunity of a large proportion of the group to that pathogen.

Question 9

Know surveillance mechanisms in place in the US and how we can improve upon/reduce water/foodborne illnesses.

Answer 9

Div of Foodborne, Waterborne & Environmental Disease (division of CDC)-foodborne and waterborne outbreaks, FDA-food safety, USDA-animal based food safety, state specific departments, Safe drinking water act-EPA

Question 10

If you have food poisoning, how do you report it?

Answer 10

Contact the dept of health in charge in state. For PA, contact Pennsylvania dept. of agriculture

Question 11

List steps of disease progression:

Answer 11

1. infection
2. incubation period
3. acute period
4. decline period
5. convalescent period

Question 12

Define: vehicle.

Answer 12

Type of fomite which can infect large numbers of individuals. Ex. food and water

Question 13

Influenza- Causative agent, reservoir, control measure, and mechanism

Answer 13

A) orthomyxo virus, RNA virus
R) birds and swine
C) new vaccines created every year
M) mutations in genome alter AA on surface-hemaglutanin (H)-attachment of virus to host cell, nuraminodase (N)-release virus from cell

Question 14

Hepatitis- Causative agent, reservoir, control measure

Answer 14

A) hepatitis virus
R) human (acute liver disease)
C) vaccines for A + B
hep c is 20% chronic liver disease

Question 15

HIV- Causative agent, reservoir, control measure, and mechanism (if applicable)

Answer 15

A) HIV retrovirus
R) primates and higher
C) public health measures, HA ART-1 protease inhibitor or 1 NNRTI + 2 NRTI, vaccination
M) macrophage + T helper cells CD4 surface protein binds to HIV, HIV envelopes and infects cell

Question 16

West Nile Virus- Causative agent, reservoir, control measure, and mechanism (if applicable)

Answer 16

A) west nile virus
R) mosquito, birds
C) public health/mosquito control
M) virus invades immune system

Question 17

Lymes disease- Causative agent, reservoir, control measure, and mechanism (if applicable)

Answer 17

A) Lyme borreliosis
R) tick
C) early-antibiotics, late-IV therapy
M) tick saliva contains two proteins that inhibit immune response, allows pathogen to survive and eventually spread to other parts of body where neutrophils can’t elimimate

Question 18

Tuberculosis- Causative agent, reservoir, control measure, and mechanism (if applicable)

Answer 18

A)

Question 19

Malaria- Causative agent, reservoir, control measure, and mechanism (if applicable)

Answer 19

A) Plasmodium

R) mosquitos

Question 20

Swine Flu- Causative agent, reservoir, control measure, and mechanism (if applicable)

Answer 20

A)

Question 21

Bird Flu- Causative agent, reservoir, control measure, and mechanism (if applicable)

Answer 21

A)

Question 22

Cholera- Causative agent, reservoir, control measure, and mechanism (if applicable)

Answer 22

A)

Question 23

Giardiasis- Causative agent, reservoir, control measure, and mechanism

Answer 23

A) giardia lamblia (beaver fever)
R) cysts in water
C)
M) ingestion of cysts, in small intestine undergo excystation to release trophosoites, these move to colon, encyst + shed (cyst=spore)

Question 24

Cryptosporidium- Causative agent, reservoir, control measure, and mechanism (if applicable) + life cycles

Answer 24

C) cryptosporidium, fecal-oral
R)
C)
M) oocysts, 4 sporozites, excretion, ingestion, excystation, sporozoites released, parasitize epithelieal cells, sexual/asexual reproduction

Question 25

Salmonella- Causative agent, reservoir, control measure, and mechanism (if applicable)

Answer 25

A) salmonellosis, g -
R) animal products
C) cook foods
M) short incubation period, organisms multiply in intestines -> bloody diarrhea

Question 26

pathogenic E coli- Causative agent, reservoir, control measure, and mechanism + different classification/descriptions

Answer 26

A) E. coli
R)
C)
M) O-LPS, K-capsule, H-flagella, F-fimbrae

Question 27

Campylobacter- Causative agent, reservoir, control measure, and mechanism (if applicable)

Answer 27

A) campylobacter
R)
C)
M) cytolytic disleading toxin-can evade immune system due to hindering division

Question 28

Listeria- Causative agent, reservoir, control measure, and mechanism (if applicable)

Answer 28

A) listeria monocytogenes
R) food, cantelopes
C) cook food?
M) long incubation period