PUBLIC HEALTH

science and art of preventing disease, prolonging life, and promoting health and human efficiency through organized community efforts. These efforts are directed toward sanitation of the environment, control of communicable infections, education of individuals in personal hygiene, organization of medical and nursing services for the early diagnosis and preventive treatment of disease, and the development of social machinery to ensure for every individual a standard of living adequate for the maintenance of health. Public health in modern times was greatly influenced by general scientific progress. Rapid advances in medical science in the 19th century revolutionized ideas about the basis of health. Physiological chemistry gave rise to the science of nutrition; clinical medicine established the specificity of disease. Most important, the centuries-old erroneous theories of how epidemics spread were finally routed. An important result of the germ theory of disease was the transformation of hospitals. They took on new meaning when the antisepsis principles of Joseph Lister were applied, and by the end of the century they began to take the chief position in community health services. During the 20th century science continued, by the discovery of vitamins, antibiotics, and much else, to give public health new tools. The study of society, particularly by means of the social survey, extended the basic concepts of public health, and the medical officer of health became something of a social scientist as well. Public health collaboration among countries originated in the fear of epidemic spread and the inconvenience to trade arising out of the practice of quarantine. From 1851 a series of International Sanitary Congresses was held in the capitals of Europe and the United States, leading eventually to the formation of the Pan American Sanitary Bureau (1902), with headquarters in Washington, D.C., and L'Office Internationale d'Hygine Publique (1909), with headquarters in Paris. After World War I the health section of the League of Nations was created (1923) with headquarters at Geneva. It was followed after World War II by the World Health Organization (1948), a specialized agency of the United Nations. WHO, also with headquarters in Geneva, absorbed both the League health office and the Paris office and thus became the major international health organization. the art and science of preventing disease, prolonging life, and promoting physical and mental health, sanitation, personal hygiene, control of infection, and organization of health services. From the normal human interactions involved in dealing with the many problems of social life, there has emerged a recognition of the importance of community action in the promotion of health and the prevention and treatment of disease; this is expressed in the concept of public health. Comparable terms for public health medicine are social medicine and community medicine; the latter has been widely adopted in the United Kingdom, and the practitioners are called community physicians. The practice of public health draws heavily on medical science and philosophy and concentrates especially on manipulating and controlling the environment for the benefit of the public. It is concerned therefore with housing, water supplies, and food. Noxious agents can be introduced into these through farming, fertilizers, inadequate sewage disposal and drainage, construction, defective heating and ventilating systems, machinery, and toxic chemicals. Public health medicine is part of the greater enterprise of preserving and improving the public health. Community physicians cooperate with such diverse groups as architects, builders, sanitary and heating and ventilating engineers, factory and food inspectors, psychologists and sociologists, chemists, physicists, and toxicologists. Occupational medicine is concerned with the health, safety, and welfare of persons in the workplace. It may be viewed as a specialized part of public health medicine since its aim is to reduce the risks in the environment in which persons work. The venture of preserving, maintaining, and actively promoting public health requires special methods of information-gathering (epidemiology) and corporate arrangements to act upon significant findings and put them into practice. Statistics collected by epidemiologists attempt to describe and explain the occurrence of disease in a population by correlating factors such as diet, environment, radiation, or cigarette smoking with the incidence and prevalence of disease. The government, through laws and regulations, creates agencies to oversee and formally inspect such things as water supplies, food processing, sewage treatment, drains, air contamination, and pollution. Governments also are concerned with the control of epidemic infections by means of enforced quarantine and isolationfor example, the health control that takes place at seaports and airports in an attempt to assure that infectious diseases are not brought into a country. This section traces the historical development of public health, beginning in ancient times and emphasizing how various public health concepts have evolved. It outlines the organizational and administrative methods of handling these problems in the developed and the developing countries of the world. Special attention is given to the developing countries and to how the health problems, limitations of resources, education of health personnel, and other factors must be taken into account in designing health service systems. Finally, there are descriptions of the most recent developments in public health, together with some indications of the problems still to be solved. Additional reading Fraser Brockington, World Health, 3rd ed. (1975), is a comprehensive discussion of public health concepts and the World Health Organization. John Bryant, Health & the Developing World (1969, reprinted 1972), studies health-care in Africa, Asia, and Latin America. John M. Last (ed.), Public Health and Preventive Medicine, 11th ed. (1980), is a definitive text. Later surveys of the organized effort to protect and improve community health include Derek Fraser, The Evolution of the British Welfare State: A History of Social Policy Since the Industrial Revolution, 2nd ed. (1984); Robert Lanza (ed.), Medical Science and the Advancement of World Health (1985); and Grace Budrys, Planning for the Nation's Health: A Study of Twentieth-Century Developments in the United States (1987).