SPHU 3170: Epidemiology

Epidemic

Occurrence in a community or region of cases of an illness that exceeds prevalence relative to usual frequency of the disease

Outbreak

Localized disease epidemic (Ex. in a town or health care facility)

Endemic

Outbreak at usual prevalence (Ex. cataracts among elderly)

Pandemic

Epidemic on a worldwide scale (Ex. COVID-19)

Epidemiology

The study of the distribution and determinants of health-related states or events in specified populations, and the application to control health problems

Distribution

Frequency and pattern of an event

Frequency (distribution)

Number of health events and the relationship of that number to size of the population

Pattern (distribution)

Occurrence of health-related events by person, place and time, place

Determinants

Factors or events resulting in change in health status

Exposures

Pertain either to contact with a disease-causing factor or to amount of the factor affects a group or individuals

• can be intrinsic or extrinsic

Risk Factor

Exposure that is associated with an adverse health outcome

3 Criteria of Risk Factors

1. Greater exposure

2. Risk factors precede disease onset

3. Observed association is not due to error

Morbidity

Illnesses and disability due to a specific disease or health condition

Mortality

Death