public health, field of medicine and hygiene dealing with the prevention of disease and the promotion of health by government agencies. In the United States, public health authorities are engaged in many activities, including inspection of persons and goods entering the country to determine that they are free of contagious disease. They are empowered to isolate persons with certain diseases and to quarantine such individuals, if necessary, for the public good. Public health officials are responsible for supervising the purity of the water, milk, and food supply as well as the persons who handle these items and the public eating places that dispense them. They are responsible for the good health of animals that supply food and for the extermination of wildlife, rodents, and insects that contribute to disease. Public health authorities are also concerned with the pollution levels in air and water, and must assure the safety of water used for drinking, for swimming, and as a source of sea food. In addition, they collect vital statistics on death rates, birth rates, communicable and chronic diseases, and other indicators of the state of public health.

The duties of carrying out the many services required to keep the population healthy and to prevent serious outbreaks of disease are divided among local, state, and federal government agencies. They provide health officers and nurses for the schools and visiting nurses for the home. They oversee the water supply, the disposal of sewage, the production and distribution of milk, and the proper handling of food in restaurants. Public health agencies impose standards of public health on local communities when needed; they give financial and technical assistance to local communities in time of crisis, such as that caused by epidemics, hurricanes, and floods.

The principal federal health agency in the U.S. today is the Public Health Services division of the Department of Health and Human Services. It consists of five agencies including the National Institutes of Health, its research arm, which conducts extensive research into neurology, blindness, AIDS, immunology, and heart disease. The Centers for Disease Control and Prevention, another agency under the Public Health Service, maintains statistical data on all diseases; it was instrumental in showing the relationship between tampons and toxic shock syndrome, as well as pinpointing the source of Legionnaire's disease to a new water-borne organism. The Food and Drug Administration is the arm charged with assuring the effectiveness and purity of food, drugs, and cosmetics. The Alcohol, Drug Abuse and Mental Health Administration was established by Congress more recently to address substance abuse and mental health problems. To carry out all these activities the public health services employ large numbers of physicians, dentists, veterinarians, laboratory technicians, nurses, sanitary engineers, health educators, psychologists, and social workers (see also Surgeon General, United States).

Because of the frequent and rapid transportation of people and disease vectors by air there has been a growing need for the monitoring of public health on a global level. This is done by the UN's World Health Organization.

managed health care, system of health-care delivery that aims to control costs by assigning set fees for services, monitoring the need for procedures such as tests and surgical operations, and stressing preventive care. Managed health-care systems include health maintenance organizations; preferred provider organizations (PPOs), networks of doctors and hospitals that adhere to given guidelines and fees in return for receiving a certain number of patients; and point of service (POS) plans, which are similar to PPOs but allow patients to go outside the network for treatment, usually at a higher cost. The term is also used to describe more traditional health-insurance plans that require that more expensive procedures be reviewed and approved by a plan official before they are performed. In managed care, the doctor is often paid a set fee or is paid a set amount monthly for each patient, a scheme called capitation. Many physicians criticize managed care systems, saying that they take away their freedom to make treatment decisions, that they are motivated mainly by economics, and that they do not consider patients as individuals. Managed health-care systems also limit doctors' incomes and what many people consider to be the abuses of the older fee-for-service system that rewarded doctors financially for doing more procedures. See also health insurance.

health-care proxy, legal document in which a person assigns to another person, usually called an agent or proxy, the authority to make medical decisions in case of incapacitation. It is, in essence, a power of attorney for health care. In many cases, the health-care proxy is used in conjunction with a living will that spells out the person's wishes regarding the extent of life-sustaining treatment desired at the end of life. It differs from a living will, however, in that the chosen agent has the authority to deal with any medical situation that may arise, not just end-of-life situations, and in that the agent can deal with circumstances not foreseen by the person in a living will. A health-care proxy gives a next of kin or other family member additional authority to make decisions; it can also be used to assign authority to someone outside the family. Health-care proxies go into effect when the attending physician determines that the patient lacks the capacity to make decisions. Prior to that time, the person retains all decision-making rights.

health maintenance organization (HMO), type of prepaid medical service in which members pay a monthly or yearly fee for all health care, including hospitalization. The term "health maintenance organization" was coined by a health policy analyst, Dr. Paul Ellwood, in the early 1970s. Most HMOs involve physicians engaged in group practice. Because costs to patients are fixed in advance, preventive medicine is stressed, to avoid costly hospitalization. One criticism of HMOs is that patients can use only doctors and specialists who are associated with the organization. Many people who have had a long-standing relationship with a family doctor or specialist have balked at what they see as a limitation of choice. "Open-ended" HMOs offer members the option of seeing a doctor who is not part of the HMO, but the patient must pay additional costs. Proponents of HMOs say that they make health care available to more people and that their emphasis on prevention results in earlier diagnosis and increased health-care savings. Numerous complaints (and lawsuits) have arisen, however, over HMOs' refusals to approve various treatments, and over the concern that the organizations skimp on care in order to realize profits. By 1996 most states had enacted laws restricting HMO rules that were seen as detrimental to patients' health. In 1997 there were 66.8 million Americans enrolled in HMOs. See also health insurance; managed health care.

health insurance, prepayment plan providing services or cash indemnities for medical care needed in times of illness or disability. It is effected by voluntary plans, either commercial or nonprofit, or by compulsory national insurance plans, usually connected with a social security program.

Health Insurance Worldwide

Compulsory accident and sickness insurance was initiated (1883-84) in Germany by Otto von Bismarck; it was adopted by Great Britain, France, Chile, the Soviet Union, and other nations after World War I. In Britain the National Health Insurance Act of 1946, which went into effect in 1948, provided the most comprehensive compulsory medical care plan introduced anywhere up to that time. Under the plan the individual obtained free medical attention from any doctor participating in the national health service. The cost was met by the national government and local taxation; a small charge for some services has been instituted since then. In 1958 the Canadian Hospital and Diagnoses Act provided full hospital service almost free of charge in public wards; more comprehensive coverage was added in 1967. The program is financed by the federal government but administered by the provinces. National health insurance has been widely adopted in Europe and parts of Asia. The United States is the only Western industrial nation without some form of comprehensive national health insurance.

Health Insurance in the United States

In the past, health insurance in the United States took the form of voluntary programs. Such programs date from about 1850, when health insurance was provided chiefly by cooperative mutual benefit and fraternal beneficiary associations. Limited coverage by commercial companies was also introduced during that period, and subsequently many plans were established by industries and labor unions.

Advocacy of government health insurance in the United States began in the early 1900s. Theodore Roosevelt made national health insurance one of the major planks of the Progressive party during the 1912 presidential campaign, and in 1915 a model bill for health insurance was presented, but defeated, in numerous state legislatures. After 1920 opposition to government-sponsored plans was led by the American Medical Association and was said to be motivated by the fear that government participation in medical care might lead to socialized medicine.

Over the years in the United States, many plans have been set up by societies of practicing physicians, but the largest enrollment has been in Blue Cross and Blue Shield plans. These were set up as community-sponsored, nonprofit service plans based on contracts with hospitals and with subscribers. Most general voluntary plans accept subscribers, in groups or as individuals. These plans extend coverage to dependents and exclude accidents and diseases covered by workers' compensation laws. Although valuable in cushioning the financial distress caused by illness or injury, voluntary health insurance not only limits benefits in order to avoid prohibitive rates but excludes many people, particularly the poor, who cannot afford it, and senior citizens, for whom the cost is often prohibitive. By the mid-1990s many of the Blue Cross companies, which had been suffering financially, were reorganizing, and by 2002 more than 20% of Blue Cross members were covered by plans that had converted to for-profit status.

During the middle of the 20th cent. it became apparent that legislation was necessary to provide medical care for the elderly. A voluntary federal-state grant-in-aid program providing medical care to the elderly was first implemented in 1961. Legislation proposed by President Kennedy to provide medical care for the aged through the social security mechanism was defeated in 1961, but in 1965, during President Lyndon B. Johnson's administration, Federal legislation in the form of Medicare for the aged and Medicaid for the indigent was enacted. Since 1966, both public and private health insurance has played a key role in financing health-care costs in the United States.

Over 70% of all medical bills are now covered by government programs and insurance, and the number of people covered by some form of health insurance increased from about 12 million in 1940 to over 225 million in 1996. About 38 million Americans were enrolled in Medicare, and there were more than 36 million Medicaid recipients. In that same year, about 187 million people were covered by private health insurance. However, more than 44 million Americans are not covered by any health insurance, and those who are have seen significant cost increases. As premiums increased from $16.8 billion in 1970 to $310 billion in 1995, and national health-care costs rose from $75 billion in 1970 to just over $1 trillion in 1996, many businesses increased the amount of money employees contribute toward their health insurance. This situation has led to continuing political pressure for restructuring of the national health-care insurance system.

Congress debated many bills for a national health insurance plan in the 1960s and 70s, and in 1973 it passed the Health Maintenance Organization (HMO) Act, which provided grants to employers who set up HMOs (see health maintenance organization). Unlike insurers, HMOs provide care directly to patients; HMOs were viewed as low-cost alternatives to hospitals and private doctors. In 1997 approximately 651 HMOs provided care to 66.8 million people.

In the 1980s and 90s political leaders again advanced a variety of national health insurance proposals. One plan backed by leading Democrats was known as "pay or play" because it would have forced employers to provide health insurance or pay into a national fund that would cover uninsured workers. A second, advanced by President G. H. W. Bush in 1992, would have provided tax breaks, vouchers, and other incentives to employers to extend health insurance benefits. A third proposal, based on the Canadian model and nationalized health care, was opposed by most doctors and the insurance industry.

In 1993, President Clinton, who had been elected on a promise of health-care reform, proposed a national health insurance program that would have ultimately provided coverage for most citizens, but opposition by insurance, medical, small-business, and other groups killed it. In 1999, Clinton and Congress battled over developing a "patient's bill of rights," to protect people from denial of service and other HMO limitations. Many individual states have developed their own health insurance alternatives by using managed-health-care systems that monitor the type of services offered and have set fees for each service, by expanding Medicaid to help serve formerly ineligible patients, and by establishing statewide or small-business health insurance alliances that pool people into a large group that has more buying power.

World Health Organization (WHO), specialized agency of the United Nations, established in 1948, with its headquarters at Geneva. WHO admits all sovereign states (including those not belonging to the United Nations) to full membership, and it admits territories that are not self-governing to associate membership. There are 193 member nations. WHO is governed by the World Health Assembly, consisting of representatives of the entire membership, which meets at least once a year; an executive board elected by the World Health Assembly; and a secretariat headed by a director-general. There are regional organizations in Africa, the E Mediterranean, SE Asia, Europe, the W Pacific, and the Americas. WHO worked to eradicate smallpox, has made notable strides in checking polio, leprosy, cholera, malaria, and tuberculosis, and sponsors medical research on tropical and other diseases. WHO has drafted conventions for preventing the international spread of disease, such as sanitary and quarantine requirements, and for reducing smoking, and has given attention to the problems of environmental pollution. WHO is also authorized to issue global health alerts and take other measures to prevent the international spread of health threats.

Pan-American Health Organization, inter-American health organization. It was established in 1902 as the International Sanitary Bureau; the present name was adopted in 1958. Its members include all the Latin American nations, Canada, and the United States. France, Great Britain, and the Netherlands are also associated with the organization on behalf of their departments and territories in the Western Hemisphere. The organization cooperates with members in developing public services, collects health statistics, and aids in the control of communicable diseases.

Occupational Safety and Health Administration (OSHA), U.S. agency established (1970) in the Dept. of Labor (see Labor, United States Department of) to develop and enforce regulations for the safety and health of workers in businesses that are engaged in interstate commerce. OSHA develops guidelines and issues regulations for safety and health standards, and conducts inspections of workplaces for compliance with these standards. In instances of noncompliance, it issues citations and proposes penalties. In the 1980s and 90s, OSHA took a more active role in protecting against health hazards in the workplace, seeking to limit the exposure of workers to hazardous substances such as lead, asbestos, pesticides, and toxic chemicals and noise.

National Institutes of Health (NIH), agency of the U.S. Public Health Service, with headquarters in Bethesda, Md. It was established initially in 1887 as a laboratory in the U.S. Marine Hospital on Staten Island in New York City, and was given its present name in 1948. The NIH conducts and supports biomedical research into the causes, cure, and prevention of disease. It maintains its own laboratories and awards grants and contracts to universities and other private research facilities. Separate national institutes function in specific areas such as cancer; heart, lung, and blood diseases; dental research; maternal and child health; allergy and infectious diseases; aging; human genome research; and mental health. It also maintains the National Library of Medicine.

Health, Education, and Welfare, United States Department of: see Education, United States Department of; Health and Human Services, United States Department of.

Health and Human Services, United States Department of, federal executive department charged with administering government health programs. Successor to the Department of Health, Education, and Welfare, which had been created in 1953, it was redesignated in 1979 with the creation of the Department of Education. The secretary advises the President on health and welfare matters. The department has several components. The Administration for Children and Families is responsible for Operation Head Start, the enforcement of child support laws, and programs concerning adoption, job training, and runaway youths. The Public Health Service is divided into 42 subdivisions; it carries out research on disease and health concerns through the National Institutes of Health, protects consumers from adulterated or untested foods and drugs through the Food and Drug Administration, and implements public health measures and monitors the spread of infectious diseases through the Centers for Disease Control and Prevention. The Substance Abuse and Mental Health Services Administration develops and analyzes information relating to the prevention and treatment of addictive and mental disorders. The Centers for Medicare and Medicaid Services administers Medicare and Medicaid. The Social Security Administration, formerly part of the department, became an independent agency in 1995 (see social security). The Administration on Aging develops policy and programs to promote the welfare of older Americans and administers grants to states to establish community programs for them.

Science and art of preventing disease, prolonging life, and promoting health through organized community efforts. These include sanitation, control of contagious infections, hygiene education, early diagnosis and preventive treatment, and adequate living standards. It requires understanding not only of epidemiology, nutrition, and antiseptic practices but also of social science. Historical public health measures included quarantine of leprosy victims in the Middle Ages and efforts to improve sanitation following the 14th-century plague epidemics. Population increases in Europe brought with them increased awareness of infant deaths and a proliferation of hospitals. Britain's Public Health Act of 1848 established a special public health ministry. In the U.S., public health is studied and coordinated on a national level by the Centers for Disease Control and Prevention; internationally, the World Health Organization plays an equivalent role.

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Science of maintaining mental health and preventing disorders to help people function at their full mental potential. It includes all measures taken to promote and preserve mental health: rehabilitation of the mentally disturbed, prevention of mental illness, and aid in coping in a stressful world. Community mental health acknowledges the relation between mental health, population pressures, and social unrest. It also deals with social problems, from drug addiction to suicide prevention. Treatment of the mentally ill through the ages has ranged from neglect, ill treatment, and isolation to active treatment and integration into the community, often in response to crusading reformers. Prevention of mental illness includes prenatal care, child-abuse awareness programs, and counseling for crime victims. Treatment includes psychotherapy, drug therapy, and support groups. One of the most important efforts is public education to combat the stigma still attached to mental illness and encourage those affected to seek treatment.

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Public or private organization providing comprehensive medical care to subscribers on the basis of a prepaid contract. HMOs deliver a broad range of health services for a fixed fee. In the prepaid group-practice model, physicians are organized into a group practice with one insuring agency. A medical care foundation, or individual practice association, usually involves multiple insurance companies and reimburses members of a loose network of individual physicians from subscribers' prepaid fees. Originally viewed as a way to control health-care costs and meet increased demand for health services, HMOs have become controversial because some limit care by refusing to pay for tests or treatment against their own doctors' advice.

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Branch of law dealing with various aspects of health care. Health law was traditionally known as legal medicine or forensic medicine and included primarily forensic pathology and forensic psychiatry, in which pathologists were asked to determine and testify to the cause of death in cases of suspected homicide or to aspects of various injuries involving crimes such as assault and rape. Today health law is applied not only to medicine but also to health care in general. Health law is especially important in cases with complicated ethical implications—for example, in the case of comatose patients who are kept alive by mechanical ventilation, when physicians and families are forced to decide whether or not it is more or less ethical to remove the ventilator. Other important aspects of health law include patients' rights and medical malpractice.

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System for the advance financing of medical expenses through contributions or taxes paid into a common fund to pay for all or part of health services specified in an insurance policy or law. The key elements are advance payment of premiums or taxes, pooling of funds, and eligibility for benefits on the basis of contributions or employment without an income or assets test. Health insurance may apply to a limited or comprehensive range of medical services and may provide for full or partial payment of the costs of specific services. Benefits may consist of the right to certain medical services or reimbursement of the insured for specified medical costs. Private health insurance is organized and administered by an insurance company or other private agency; public health insurance is run by the government (see social insurance). Both forms of health insurance are to be distinguished from socialized medicine and government medical-care programs, in which doctors are employed directly or indirectly by the goverment, which also owns the health-care facilities (e.g., Britain's National Health Service). Seealso insurance.

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Extent of continuing physical, emotional, mental, and social ability to cope with one's environment. Good health is harder to define than bad health (which can be equated with presence of disease) because it must convey a more positive concept than mere absence of disease, and there is a variable area between health and disease. A person may be in good physical condition but have a cold or be mentally ill. Someone may appear healthy but have a serious condition (e.g., cancer) that is detectable only by physical examination or diagnostic tests or not even by these.

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Public-health agency of the UN, established in Geneva in 1948 to succeed two earlier agencies. Its mandate is to promote “the highest possible level of health” in all peoples. Its work falls into three categories. It provides a clearinghouse for information on the latest developments in disease and health care and establishes international sanitary standards and quarantine measures. It sponsors measures for the control of epidemic and endemic disease (including immunization campaigns and assistance in providing sources of pure water). Finally, it encourages the strengthening of public-health programs in member nations. Its greatest success to date has been the worldwide eradication of smallpox (1980).

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U.S. government agency that conducts or supports biomedical research. It is made up of numerous specialized institutes (e.g., National Cancer Institute; National Heart, Lung, and Blood Institute; National Institute on Aging; National Institute of Child Health and Human Development; and National Institute of Mental Health). Part of the Department of Health and Human Services, it also trains health researchers; disseminates information; and maintains other offices and divisions, the National Library of Medicine (the foremost source of medical information in the U.S.), and several research centres.

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