The multiple environmental influences on health mean that medical advances have played but one small part in improving both life expectancy and the quality of life.
How have disease patterns changed?
People today are living longer; especially Westerners. This increase in life expectancy over the past two centuries is closely related to a decrease in infectious diseases, such as cholera, measles and influenza. There has been a corresponding rise in degenerative diseases – cancer and heart disease, for example - in the resulting ageing population.
© WaterAid
Nevertheless, in less economically developed countries (LEDCs), access to basic sanitation including clean water remains a problem, and diseases that have been eradicated in wealthier regions are rife.
In this tutorial, we explore patterns of infectious disease, covering three areas:
How are geography and the environment linked to epidemiology?
We investigate the close links between geography and the development of the science of epidemiology, which examines the distribution, occurrence and spread of disease.
Can we predict the spread of infectious disease?
Next we look at theories and models that attempt to predict the spread of infectious diseases. We will use historical evidence from influenza and cholera epidemics, among others, to assess the effectiveness of these theories and models.
Has modern technology influenced the spread of ill health?
The final section considers the many ways in which modern technology might have influenced the spread of ill health.
© Cathay Pacific Airways Limited
Women fetching water, Mozambique.
Air travel has increased the speed of the spread of disease and increased the threat of epidemics of global proportions.
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Geography of health
Introduction
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