Like this study set? Create a free account to save it.

Sign up for an account

Already have a Quizlet account? .

Create an account


The constant presence of a disease or infectious agent within a given geographical area or population group
ex. TB in the US


The occurrence in a community or region of cases of an illness with a FREQUENCY clearly in excess of normal expectancy
(Usually an annual comparison of this year to last year)


An epidemic occurring over a very wide area, crossing international boundries and affecting a large number of people
ex. HIV, Plague Spanish Flu or 1918

Herd Immunity

The immunity of a group or community. The resistance of a group to invasion and spread o an infectious agent based on the reistance to infection of a high proportion of individuals.

What % of the population needs to be vaccinated for Measles in order to get herd immunity?


Does an association between 2 variables imply a cause and effect relationship?

ex. Every child that has leukemia in the US ate a hotdog before they go leukemia. It is an association, but doesn't show there is a cause and effect relationship

Which is the strongest of all the criteria that help to establish a cause and effect releationship?

Temporality--Being able to have a clear timeline that shows exposure followed by disease

Who was one of the first people to look at epidemiology? He investigated cholera outbreaks in London and tracked the causative agent to a water pump.

John Snow

Who is John Snow?

He is one of the first epidemiologists
He is famous for investigating a cholera outbreak in London down to a water pump

Who is Ignaz Semmelweis?

He is an early epidemiologist who noticed that women being treated by students & physicians, that were also performing autopsies were dying more than women treated by midwives.

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions and try again


Reload the page to try again!


Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

Voice Recording