public health

Science of preventing disease and promoting health at community level rather than on an individual basis. At its most basic it includes the provision of an adequate supply of clean water and the safe disposal of sewage. It also includes the provision of an adequate number of doctors, nurses, and hospitals to serve each community, and ensuring that medical services are available to everyone, whatever their financial circumstances.

Other facets of public health are epidemiology, the study of disease and its occurrence within a community, immunization against disease, microbiology, the study of disease-causing bacteria, and virology, the study of viruses.

US health care In the USA state and local agencies provide public health services under the umbrella organization of the federal Public Health Service. Such services are not free for everybody, and people are expected to take out health insurance to pay for any treatment they may need. However, since 1965 nearly all people over the age of 65 can sign up for Medicare, a federal insurance programme that covers a large part of the cost of medical and hospital treatment.

State health departments control standards of health care, including food quality, the environment, and housing, and provide back-up services such as specialized laboratories and disaster services.

Basic needs In the most isolated communities in developing countries, the first essential for public health is a supply of clean drinking water. Polluted water is a major cause of disease. The second requirement is to ensure that human and other waste is disposed of in such a way that it cannot contaminate the wells or springs from which drinking water is drawn. Both these steps are vital in the prevention of disease.

Statistics The next necessity is a supply of qualified doctors. In some developing countries these may be supplemented by paramedics, people with limited medical training who can handle simple medical problems. Medical statistics based on the number of doctors in relation to the population show a great variation, ranging from 1 doctor for every 282 people in Uruguay to 1 for every 22,452 in Ghana. Statistics also show a great variation in the number of hospital beds available per head of population.

Health services Hospitals of a sort have been in existence for hundreds of years. The Romans had hospitals to treat their sick and wounded soldiers. For many years hospitals were established and run by religious bodies, for example by Buddhist monasteries in Asia, and later by Christian monasteries in Europe. The monastic hospitals were at first only for the care of sick monks, but the religious houses offered shelter to travellers, and their hospital wards later opened to them as well. One of the earliest was the Hotel Dieu in Paris, probably founded in the AD 600s. St Thomas's Hospital in London began as part of a priory in 1106, and St Bartholomew's, in the same city, was founded by Rahere, an Augustinian canon, in 1123. Several of the early hospitals in the USA began as almshouses in the 1700s. Nursing as a career did not exist until the 1800s, but was carried out by members of religious communities, or in people's homes by the women of the family. Official bodies took little interest in public health until quite recently, except for the establishment of lazar houses to isolate lepers when leprosy was a common disease in Europe.

International health care The first international body to deal with public health was the International Red Cross, founded in 1864. With the formation of the United Nations (UN) after World War II, the World Health Organization (WHO) was set up as one of its agencies. It coordinates efforts to improve community health in developing countries, identifies outbreaks of such diseases as influenza, which can take many forms, and organizes programmes of vaccination to prevent them from spreading. One of its greatest triumphs was the eradication of smallpox, announced in 1980.