What is Public Health?
Public Health is the science of optimising the overall health of a population based on continuous
population health analysis. It involves promoting health, preventing disease and prolonging healthy life through the organised efforts of society.
The World Health Organisation defines health as "a state of complete physical, mental, social and spiritual wellbeing and not the mere absence of disease or infirmity"
[1].
A true Public Health definition is even broader including, for example, nutritional, intellectual, environmental and occupational factors.
Many diseases are preventable through simple, non-medical methods. This includes both:
- Communicable diseases – diseases that can be controlled through, for example, improvements in sanitation and the availability of clean drinking water and food)
- Non-communicable diseases – diseases that can be controlled through, for example, health education about exercise and diet, and legislation to ban tobacco smoking in public places
Protecting the health of the population is typically seen as one of the prime responsibilities of government, and leaders use a variety of Public Health techniques to increase length and quality of life, helping ensure stability and prosperity.
Public Health techniques include both:
- Direct means (e.g. vaccines, or legislation to ban smoking in public places)
- Indirect means (e.g. health education, and lobbying)
Worldwide, Public Health is increasingly evidence-based, with data used to identify priority areas and drive effective initiatives through close monitoring of impact. We are proud to be working with international partners to contribute to the global evidence-base.
History
The 20th Century
The dramatic increase in average life span in developed countries during the 20th century is widely credited to Public Health achievements, such as vaccination programmes, control of infectious diseases, better safety polices such as motor-vehicle and worker safety, improved family planning, and fluoridation of drinking water.
As the rate of infectious diseases in the developed world decreased through the 20th century, Public Health began to put more focus on chronic diseases such as cancer and heart disease.
The 1980s
Since the 1980s, the growing field of
population health has broadened the focus of public health from individual behaviours and risk factors to population-level issues such as inequality, poverty, and education. Modern Public Health is often concerned with addressing determinants of health across a population, as well as influencing individual behaviours. This period also saw an increase in the use of evidence base for public health decision making.
Social determinants of health
Our health is affected by many factors including where we live, genetics, our income, our educational status and our social relationships – these are known as the "social determinants of health." A social health gradient runs through societies, with those that are poorest often suffering the worst health. However even those in the middle classes typically have worse health outcomes than those of the highest social levels (WHO, 2003). Modern Public Health seeks to address these health inequalities by advocating for population-based policies that improve the health of the whole population.
Updated: November 2007
[1]WHO: Constitution of the World Health Organization, Geneva 1946