Public sector provision of social, economic, medical and infrastructural measures which ensure the protection and improvement of the physical and mental health of a society. Such services are usually provided at little or no direct cost to the individual receiving them, and comprise delivering adequate nutrition, sanitation, immunization and treatment to the public in an organized way in order to prevent disease, prolong life and promote physical and mental efficiency.
To a large extent public health can been seen as the application of knowledge about the infrastructures which underpin social life for the promotion of the public's health. These systems include the food, water, transport, occupational and energy generation systems as well as the health services and community and family networks.
When governments become directly involved in the health sector – by providing public health programmes or financing essential clinical services for the poor – policymakers face difficult decisions concerning the allocation of public resources. Administering public health programmes is done differently according to the social structure of the society. This has extensive economic, political and cultural ramifications.
A few major risk factors are responsible for a large portion of the global disease burden and eliminating them could result in important health gains, A 1993 study reported in The Lancet was the first to estimate the disease burden of multiple risk factors on a global scale, Disease burden and injury attributable to 20 major risk factors in 14 regions around the world was evaluated. Forty-seven percent of premature deaths and 39% of the total disease burden in 2000 were due to the joint effects of the 20 risk factors. The risk factor that contributed the most to the disease burden was childhood and maternal underweight, followed by unsafe sex, high blood pressure and tobacco use. Together, the risk factors accounted for more than 90% of diarrhoea cases, 83% to 89% of ischaemic heart disease cases, 70% to 76% of stroke cases, 72% of lung cancer cases, 55% to 62% of lower respiratory infection cases and 60% of COPD cases. Simultaneous elimination of all risk factors would increase global life expectancy by 9.3 years. However, the benefit would vary greatly by region. The study indicated that the gain in some parts of sub-Saharan Africa would be 16.1 years, while the increase was only 4.4 years in developed regions of the western Pacific.
This strategy features in the framework of Agenda 21 as formulated at UNCED (Rio de Janeiro, 1992), now coordinated by the United Nations Commission on Sustainable Development and implemented through national and local authorities. Agenda 21 recommends that rational and affordable approaches to the establishment and maintenance of health facilities should be developed and implemented.
For any given amount of total spending, taxpayers and, in some countries, donors want to see maximum health gain for the money spent. An important source of guidance for achieving value for money in health spending is a measure of the cost-effectiveness of different health interventions and medical procedures – that is, the ratio of costs to health benefits. Cost and effectiveness data on health interventions are often weak. Nonetheless, cost-effectiveness analysis is being used as a tool for choosing among possible health interventions in individual countries, for addressing specific health problems such as the spread of AIDS and to guide donor aid spending. For example, UNICEF spends more than US$800 million a year primarily on immunization, health care, nutrition and basic education in 138 countries.
The public health activities with the largest payoff will vary from country to country: vitamin A and iodine supplementation in India and Indonesia, anti-smoking campaigns in China, and policies to reduce traffic injuries in urban areas of Sub-Saharan Africa. Several activities stand out as highly cost-effective in any country, including: (a) immunization (especially in low-income countries); (b) school-based health services; (c) information and selected services for family planning and nutrition; (d) programmes to reduce tobacco and alcohol consumption; (e) regulatory action, information and limited public investments to improve the household environment; (f) AIDS prevention.
When essential clinical services are combined with these basic public health measures, the share of current illness that could be eliminated is perhaps 32% for low-income countries and 15% for middle income countries. This reduction in disease is equivalent (in disability-adjusted life years) to saving the lives of more than 9 million infants each year. The total cost of implementing the public health measures described above plus a minimum package of essential clinical services is around $12 per capita per year in low-income countries and $22 per capita in middle-income countries.
Adoption of cost-effective public health measures in all developing countries would require a quadrupling of expenditures on public health, from $5,000 million at present to $20,000 million a year, and an increase from about $20,000 million to $40,000 million in spending on essential clinical services. In the poorest countries, governments typically spend about $6 per person for health and total health expenditures (including private and donor aid) and are around $14 per person. There, paying for an essential package of public health care for all will require a combination of increased expenditures by governments, donor agencies and patients and some reorientation of current public spending for health. In middle-income countries, where public spending for health averages $62 per person, a basic package is financially feasible if the political commitment exists for shifting existing resources away from discretionary services with lower cost-effectiveness toward public health programmes and essential clinical care.
The health gain per dollar spent varies enormously across the range of interventions currently financed by governments. Redirecting resources from interventions to those of high cost effectiveness could dramatically reduce the burden of disease without increasing expenditures.
The poor of the world have the greatest remaining health needs. Government policies that promote equity and sustained growth together will therefore be better for health than those that promote growth alone. Policies to expand schooling are also crucial for promoting health. People who have had more schooling seek and utilize health information more effectively than those with little or no schooling.
No amount of personal effort can guard one's good health adequately, without the corporate effort required by the provision of basic sanitation, food inspection, innoculations, clean water, nutritious food production and various forms of pollution control.
Potential health gains from reducing major known but often over-looked risks are enormous, especially for those societies that currently endure the worst health conditions. There is a need for our public health system to put greater emphasis on disease prevention by recognizing clusters of risk factors and designing policies and programs for addressing them, rather than merely treating their consequences.
Providing free health services decreases the capacity of the human species to respond to laws of natural selection and thereby decreases the ability for human populations to respond to changes in the environment.