Public health focuses on promoting and protecting the health of entire populations, contrasting with clinical medicine, which treats individuals after they become sick. This field operates on the principle that organized community efforts can prevent disease, injury, and premature death, thereby improving the quality of life for everyone. To achieve this broad goal, the discipline is structured around a framework of three distinct, yet interconnected, functions that guide all activities at the local, state, and national levels. These functions provide a standardized approach to identifying problems, developing solutions, and ensuring those solutions reach the people who need them most.
Monitoring Health Status
The first fundamental function involves systematically collecting and analyzing information about the health of a community, essentially answering the question, “What is the problem?” This process requires constant vigilance to monitor health status, identify trends, and understand the factors influencing well-being within a population. Public health professionals continuously track data points such as birth and death records, disease incidence rates, and injury statistics to build a comprehensive community health profile.
This function includes detailed disease surveillance, tracking the spread of infectious diseases and investigating non-infectious conditions such as diabetes or heart disease. Epidemiologic investigations are conducted to diagnose and determine the root causes of health problems and hazards, allowing agencies to identify high-risk populations and pinpoint where resources should be directed.
Creating Public Health Action Plans
Once health data is collected and analyzed, the second core function, Policy Development, begins, focusing on translating that knowledge into concrete action. This phase is about responding to the identified health needs by creating and implementing public health policies and plans. The goal is to inform, educate, and empower the public about health issues, such as running campaigns to increase vaccination rates or promoting healthy eating habits.
Developing an effective action plan also requires mobilizing community partnerships and coalitions to address problems that no single agency can solve alone. Furthermore, this function involves creating and championing policies, plans, and laws that support community health, such as advocating for municipal smoking bans or establishing standards for water safety and sanitation.
Ensuring Community Access and Enforcement
The third and most complex function, Assurance, focuses on making certain that the necessary services and protections are actually available and accessible to the public. It is the mechanism that guarantees the success of the policies developed in the previous stage. A primary aspect of Assurance is the utilization of legal and regulatory actions designed to protect public health, including enforcing laws like restaurant sanitation codes and workplace safety standards. Another important component is linking people to needed personal health services, especially for those facing systemic barriers to care. Assurance also includes building and maintaining a competent public health workforce and continuously evaluating the effectiveness and quality of public health programs.
The 10 Essential Services Framework
The three core functions—Assessment, Policy Development, and Assurance—are further operationalized through a detailed framework known as the 10 Essential Public Health Services (EPHS). This framework provides a set of specific activities that public health agencies should undertake in every community to fulfill their mission. The EPHS organizes the day-to-day work of public health practitioners under the three broad umbrella functions.
For example, the Assessment function is detailed by services that involve monitoring health status and investigating health problems. Similarly, the Policy Development function encompasses services focused on informing, educating, mobilizing partnerships, and developing laws, while the Assurance function is supported by services related to law enforcement, linking people to care, building the workforce, evaluation, and research.