Epidemiology and Public Health Introduction, Part II

Changing Patterns of Community Health Health patterns in constant state of flux Infectious versus chronic diseases Population and age-related

Chain of Infection Etiological agent Source/Reservoir Portal of exit Mode of transmission Portal of entry Susceptible host

Modes of Transmission Contact transmission Vehicle transmission Vector transmission

Classes of Epidemics Common source (vs. sporadic) Point source Intermittent Continuous Propagated Your Assignment: Define these terms & identify which apply to the following three graphs

Disease Investigation Establish diagnosis Identify specific agent Describe according to person, place and time Identify source of agent Identify mode of transmission Identify susceptible populations

Epidemiology and Clinical Practice Clinical practice dependent on epidemiology Epidemiology defines natural history of disease Even descriptive information is useful

The Epidemiologic Approach Multistep process First - determine association Then prove causation Not all associations are causal Examine validity, false assumptions- e.g. - fluoride in water

Analytic Studies Type of study Design Analysis of data

Epidemiology and Prevention Identify high risk populations Modify risks Prevent exposures

Levels of Prevention Primary Secondary Tertiary

Levels of Prevention (cont’d) Primary Involves halting any occurrence of a disease or disorder before it happens

Levels of Prevention (cont’d) Secondary Health screening and detection activities

Levels of Prevention (cont’d) Tertiary Retard or block the progression of condition