Epidemiological Transition Model

Question 1

What is the epidemiological transition model?

Answer 1

A model which suggests that over time as a country develops there will be a transition from infectious disease to chronic and degenerative diseases as the main cause of death

Question 2

First stage of the epidemiological transition model

Answer 2

Age of infection and famine:

• Life expectancy of 20-40 years
• Poor sanitation and hygiene; unreliable food supply
• Infections; nutritional deficiencies

Question 3

Second stage of the epidemiological transition model

Answer 3

Age of reducing pandemics:

• Life expectancy of 30-50 years
• Improved sanitation; better diet
• Reduced number of infections; increases in occurrences of strokes and heart disease

Question 4

Third stage of the epidemiological transition model

Answer 4

Age of degenerative and man-made diseases:

• Life expectancy of 50-60 years
• Increased ageing; lifestyles associated with poor diet, less activity, and addictions
• High blood pressure, obesity, diabetes, smoking-related cancers, strokes, heart disease and pulmonary vascular disease

Question 5

Fourth (and final) stage of the epidemiological transition model

Answer 5

Age of delayed degenerative diseases:

• Life expectancy of 70+ years
• Reduced risk behaviours in the population; health promotion and new treatments
• Heart disease, strokes and cancers are the main causes of mortality but treatment extends life. Dementia and ageing diseases start to appear more

Question 6

The three contexts to the epidemiological transition model

Answer 6

• Classical/western model: e.g. western Europe where a slow decline in death rate is followed by lower fertility
• Accelerated model: e.g. parts of Latin America where falls in mortality are much more rapid
• Contemporary/delayed model: e.g. sub-Saharan Africa where decreases in mortality are not accompanied by decline in fertility