Introduction Flashcards
Epidemiology etimology
EPI = UPON
DEMI = PEOPLE
OLOGY = STUDY
The study of what is upon the people
Epidemiology definition (Gordis)
The study of how diseases or health characteristics are distributed in populations and the factors that determine this distribution.
Epidemiology definition (Porta)
The study of the distribution and determinants of health-related states or events in specified populations and the application of this study to control of health problems.
Epidemiologic transition
Shift in the last century from infectious diseases to chronic diseases.
Due to sanitation, water treatment, food preparation, hygiene.
1900’s US experienced scientific advances.
Why use epidemiologic evidence?
Identify subgroups in population who are at risk for disease
1. Direct preventive efforts such as screening programs for early detection
2. Identify specific factors or characteristics that put them at high risk and subsequently modify those factor (Modifiable and non modifiable risk factors)
Objectives epidemiology
- Look for etiology (How, what, when)
- Determine extent of disease (where)
- Study natural history and prognosis (severity)
- Compare old and new models of healthcare delivery (are they working)
- Develop public policy (prevention and promotion)
Primary prevention
Preventing the initial development of a disease or from ever ocurring.
Immunization, use of suncreen, no smoke, reduce exposure to risk factor
Pre-Pathogenesis or pre-Clinical
Secondary prevention
Early detection of existing disease (recognize it early) to reduce severity and complications. (avoid progression).
Screening for cancer, mammograms, stool samples, colonoscopy.
Pathogenesis/Clinical (onset, symptoms, diagnosis).
Tertiary prevention
Prevent disease complications and reduce disability or impact of disease
Rehabilitation stroke and physicial therapy and even medications use
Pathogenesis/Clinical (onset, symptoms, diagnosis and treatment).
Natural History of Disease
- Prepathogenesis / Pre-clinical
- Pathogenesis / Clinical
Pre-pathogenesis / Pre-clinical
Occurs before the onset of disease, person is free of disease
Pathogenesis / Clinical
Biologic onset of disease
Hippocrates
- Physician in ancient greece
- First true epidemiologist and father of modern medicine
- Used supernatural means to explain disease (Humoral theory)
- Conclusions on observations
- Disease infleunced by host & environment
John Graunt
- London tradesman, published book bills of mortality
- The name was used for weekly and annual births and deaths started in england
- Forerunner vital statistics
- Quantified disease patterns, and associate births and deaths with age, sex and other factors
- Showed more frequency of births and deaths in men than in female and infant mortality high
James Lind
- Scotland surgeon
- Pioneer naval hygiene
- First ever clinical trials
- Citrus cured scurvy (Vit C deficiency)
- Experimental trial to identify causes and treatment of scurvy
William Farr
- London Medical statistician in england and wales
- Founder modern epidemiology
- Used Graunt work, used vital statistics
- First study examining connection of ocuppation and mortality
- Need of population studies to describe disease cause or etiology (multifactorial etiology)
- Relationship of incidence and prevalence
John Snow
- England pioneer of epidemiology
- Found cholera was transmitted by contaminated water
- Patterns of cholera outbreak using spot map London. Case of Broad Street Bump
- Cases around pumps. Removed handle of city bumps, reduced spread
20th Century highlights
- Sanitation
- Vaccines
- Tobbaco
- Pasteurization
- Fluoridation
- Seat belt
- Workplace safety
