Epidemiology



I. What does an epidemiologist do?

II. Definitions

endemic-disease constantly present in a particular geographic area

epidemic-disease with an unusually high incidence

pandemic-worldwide severe epidemic

morbidity-illness (morbidity rate)

mortality-death (mortality rate)

incidence-number of new cases in a specified group in a period of time

prevalence-number of total cases in a specified group at any one time

CDC-Centers for Disease Control

MMWR-Morbidity and Mortality Weekly Report

III. Spread of disease

reservoirs

entry of pathogen

transmission

person to person

vehicle

vectors

examples

Yersinia pestis: pg. 620-621

Plague information (NCID)

Plague case, Arizona (MMWR)

Mycobacterium tuberculosis: pg. 481-485

Tuberculosis case (MMWR)

Tuberculosis information (WHO)

IV. How do epidemiologists study the spread of disease?

Descriptive

who

where

when

Analytical

retrospective

prospective

Example

V. Disease eradication