Public health is a broad field that involves the study, monitoring and improvement of a population’s overall well-being. People working in public health work to help keep communities healthy by developing and implementing child wellness programs, disease prevention efforts, education, disaster relief and a variety of other services.
In addition to government-funded initiatives, there are a number of non-governmental organizations focused on public health. These include professional associations (such as the aforementioned ASTHO and NACCHO), community-based organizations, and philanthropic groups. There are also a large number of academic institutions that offer baccalaureate degrees in public health (66 schools, 164 programs).
A major component of public health is the prevention of communicable diseases. Other key public health activities include educating the general public on how to live a healthier life through things like proper diet, exercise and hygiene.
Historically, much of public health was conducted at the local level. For example, early epidemiologist John Snow mapped clusters of cholera cases to demonstrate that poor sanitation was the source of many of the outbreaks. The first state-level health department was established in New York after the Civil War and other such departments followed throughout the country as understanding of germ theory grew.
At the federal level, the Constitution grants the government a limited set of powers related to public health. This includes imposing quarantines and other measures that concern the introduction of disease into the United States from foreign countries or across state lines, funding certain public health programs through supplemental appropriations during epidemics and pandemics, and coordinating emergency preparedness among different governmental agencies.