Lecture 8- Definitions and History of Epidemiological Principles

Question 1

What is epidemiology

Answer 1

Concerned with distribution and determinants of health and diseases, morbidity, injuries, disability, and mortality in populations, study of disease patterns and transmission

Question 2

Who is an epidemiologist

Answer 2

Strives to study and control the factors that influence the occurrence of disease of health related conditions

Question 3

Who is John Snow

Answer 3

Father of epidemiology, believed outbreak of Cholera in London during mid 19th century was spread by contaminated water

Question 4

Miasmatic theory of disease

Answer 4

An explanation for infectious disease- disease was transmitted by a miasm or cloud that clung low on the surface of the earth

Question 5

What is a major epidemiological transition in diseases

Answer 5

In recent years diseases related to life style and chronic diseases like diabetes, obesity, hypertension and cardiovascular disease

Transition from causes related primarily to infectious and communicable diseases to chronic, degenerative diseases. Living longer but unhealthier

Question 6

Distribution

Answer 6

Implies that diseases do not occur randomly

Question 7

Determinants

Answer 7

Factors that can cause a change in a health condition or outcome

Question 8

Morbidity

Answer 8

Illness due to specific disease or cause

Question 9

Mortality

Answer 9

Death due to specific disease or cause

Question 10

Endemic

Answer 10

Habitual prescience or usual occurrence of a disease within a given geographic area

Examples: plague- endemic among rodents in Arizona, rabies- several species across US, valley fever- in Arizona

Question 11

Epidemic

Answer 11

Occurrence of an infectious disease clearly in excess of normal expectancy and generated from a common or propagated source

Examples: upper respiratory infections, human rabies, outbreaks of vibrio infections following hurricane Katrina

Question 12

Pandemic

Answer 12

Worldwide epidemic affecting an exceptionally high portion of the global population

Examples: COVId-19, 1918 influenza, HIV/AIDS

Question 13

Sporadic

Answer 13

Disease occurring singly, widely scattered, not epidemic or endemic

Examples: human rabies, creuztfedlt Jakob disease

Question 14

What is natural history of disease

Answer 14

1. Exposure to pathogen
2. Biological onset of disease (Start of preclinical phase)
3. Symptoms appear (end of preclinical phase and start of clinical phase)
4. Diagnosis (clinical phase)
   Therapy begun (clinical phase)
5. Outcomes- cured or died