Epidemiology Flashcards
What is Epidemiology?
The study of the [], distribution, and [] of health and [] in a population…
- occurence
- determinantts
- disease
What is prevalence vs incidence?
-
Prevalence - of a disease is the total number of new and existing cases in a population in a given time
- Total number of people with a disease
- Can be expressed as percentage
- Incidence - of a disease is the number of new cases of the disease in a given period of time.
Are mobidity and Prevalence basically the same?
Yes
Morbidity…
- Is a [] condition
- [] - [] are the presence of two or more diseased [] within an individual
- Morbidity also used to describe the [] of a disease in a population
- diseased
- Co-morbidities, states
- rate
Mortality…
- measure of [] within a population due to any number of causes
- deaths
- not the same at morbidity.
Using the examples of the common cold and ebola - differntiate morbidity and mortality….
- Morbidity and Mortality do not go hand in hand.
- Common Cold - high morbidity but low mortality
- Ebola - low morbidity but high mortality
What is a diseases “progression” through stages in its host?
- Infection - organism invades host
- Incubation - no symptoms yet.
- Prodromal - mild symptoms
- Acute Phase - most sever signs and symptoms
- Decline - disease and symptoms are subsiding
- Convalescent Period - patent regains strength and returns to normal.
Which disease stage experience the most sever symptoms?
Prodromal or Period of decline?
- Pysche!
- Neither should - the acute phase experiences the most sever signs and symptoms
In which disease stage is the disease most likely gone from the host?
Decline or Convalescent
Convalescent
An Acute Infection can be a [] force. How?
- Selective Force
- As a population we do not have a good immune response/response yet…since it is the first time we experience it. So it is most likely to be deadly.
Do organisms that cause chronic infections lose or gain virulence?
- It depends.
- Most pathogens that are well adapted will become less and less virulent over time
- Chlamydia for example - doesnt really kill peeps.
- There are some exceptions though.
Since the parasite/virus/bacteria most likely needs the host to survive…[]-[] of host and parasite is common.
Co-evolution
A disease is [] if it is not usually presnt in a population and occurs infrequently
sporadic
An [] disease is constantly present in a populaiton, usually at low incidences.
endemic
A disease [] occurs when a number of cases of a disease are reported in a short period of time.
outbreak