Medical Microbiology #9

Question 1

Epidemiology vs Pathology:

Answer 1

Epidemiology: Study of the spread and control of disease in a population
Pathology: Study of disease in individual

Question 2

2. Explain why morbidity data may be more useful than mortality data.

Answer 2

Morbidity data comes first and can prevent mortality. Which is good. Additionally the goal of morbidity data will appear in greater numbers.

Question 3

Describe three general approaches to controlling the spread of infectious disease through a population, and be able to apply these approaches to diseases spread by different means.

Answer 3

1: Reservoir
2: mode of transmission
3: host

treating

1: eliminate reservoir
2: Block mode of transmission
3: Vaccination (prepare host)

Example
Yersinia pestis
1: Reservoir: Rats –> kills rats (rat traps)
2: mode of transmission: Fleas –> kill fleas, wear flea collars
3: humans: vaccine.

Question 4

4. Explain the concept of “herd immunity.”

Answer 4

A disease will stay endemic as long as a certain % of the population required to have a vaccine in order to stop it from having an epidemic.
For influenza it is ~80% of population and ~90% of at risk individuals must be vaccinated.

Question 5

Endemic
Epidemic
Pandemic

Answer 5

Endemic: disease present in low levels in a population
Epidemic: disease present in large percentage of individuals in a population
Pandemic:disease present in large percentage of individuals in the world

Question 6

Mortality rate and morbidity rates are measured with?

Answer 6

Instances per 100,000 individuals. Or percentage rates.

Question 7

fomite:

Answer 7

Nonliving object capable of carrying a disease.

Question 8

incidence rate:

Answer 8

What percentage of the population have had the disease

Question 9

Prevalence Rate:

Answer 9

Prevalence Rate: is the proportion of people in a population who have a particular disease at a specified point in time, or over a specified period of time

Question 10

propagated epidemic (host-host epidemic):

Answer 10

a person returns from the new york on a flight. He coughs all the way home on the bus. And at work tomorrow.

Will show a gradual increase and gradual drop in incidence rate over a relatively long period of time (vs common source epidemic)

Question 11

Common Source epidemic:

Answer 11

Everyone goes to Joe’s diner and orders the fresh crab. It isn’t that fresh. 30 people report to the hospital the next day.

Has a rapid spike in incidence rate, followed by a rapid drop. Lasts a short time.

Question 12

transmission agent:

Answer 12

how the disease is transferred
1 Airborne:
2 Indirect:
 - Fomite
 - Vector
3 Direct:
 - droplet
 - getting it on

Question 13

Zoonoses

Answer 13

Zoonoses are infectious diseases of animals (usually vertebrates) that can naturally be transmitted to humans

Question 14

Vehicle:

Answer 14

An inanimate object which helped transmit a disease.