Delineation of group involved

Age, gender, race distribution

Socioeconomic status, occupation, education

Health habits & behaviors or lifestyle

Health history-natural resistance, hereditary characteristics

Geographical distribution in the area affected

Physical environment

Social environment

Economic environment

Family environment

Chronological distribution of onsets in cases by days, weeks, months

Incubation period

Seasonal trends

Onset of event

Duration of event

Analytic Epidemiology: examines the origins & causal factors found in descriptive epistudies

-Cohort Studies

-Case Control Studies

-Cross-sectional Studies

-Ecological Studies

Establish existence of epidemic

Confirm the diagnosis

Collect all cases

Characterize cases (person, place, time)

Look for trends

Form hypothesis

Test

Plan strategy for control

Implement the control strategy

Demographic factors

Physical & Psychological factors ~ levels of health

Lifestyle factors ~ behaviors

Immunity

virus/bacteria/fungi/ parasites;

transmission & virulence

radiation/ temperature/noise

gas/poisons/ allergens

Physical: water/air/climate

Biological: vectors/food

Social & Economic: for example ~

family-relationship with community (ecomap); population density

Actions designed to prevent an illness or disease from occurring; Aimed at persons who are susceptibleto illness/disease, however have no pathology

Reduces the probabilityof a specific illness occurring

Includes active protectionagainst unnecessary stressors or threats