What is Public Health?

The discipline of public health is the science and practice of promoting health and preventing disease or injury within and across populations. Professionals in the field contribute through education, policy work, research, administration, regulating health systems and health professions, and promoting ethical practices. Additionally, public health is concerned with equity and thus with promoting health for the most vulnerable or underserved populations or individuals within society. Last but not least, public health focuses on the health among populations, although understanding individual behavior and assessing individual risk factors is crucial to these efforts.

Public health emerged as a discipline out of 19th century social reform movements in Europe and the U.S. that sought to improve general health and social conditions for the poor. In this period, medical, biological, and social sciences were expanding their understanding of the distribution of and biosocial determinants of disease and health of populations. Since that time, public health has been thought to involve four key perspectives that still remain salient to many definitions of public health: (1) an evidence-based analysis of health-related decisions and behaviors using data such as vital statistics, disease surveillance, and laboratory science; (2) a focus on populations rather than individuals; (3) an emphasis on prevention as well as curative or rehabilitative care; and (4) the goal of equity and a focus on underserved or vulnerable populations. Equally important, the discipline understands health as a public good that is shaped by systems and institutions as much as individual stakeholders that are trying to promote the health of communities.