Public Health Health Article

Definition

Public health is the science and clinical practice of population and community-based efforts to prevent disease and disability, and promote physical and mental health. It considers the health of groups, communities, or populations as opposed to the health of individuals. Public health addresses a variety of medical and social issues including:

• environmental health
• nutrition and food safety
• immunization and infectious diseases
• injury and violence prevention
• maternal, infant, and child health
• substance abuse
• chronic disease prevention and treatment
• access, availability, and affordability of health care
• education, screening, and outreach services

Description

The science of public health is called epidemiology. It is the study of the occurrence of disease in such naturally existing populations as nations, cities, or communities. The term "epidemiology" comes from the Greek word epidemic, which means "upon the people." The earliest epidemiologists (public health scientists) worked to prevent the spread of epidemics.

Today, epidemiologists gather and analyze information about populations to manage and prevent disease. Epidemiologists are trained in highly specialized research methods: surveillance, investigation, analysis, and evaluation. Surveillance refers to systematic data collection and analysis; it enables the epidemiologists to detect changes that may require investigation. Epidemiological investigation involves observation, detailed descriptions of the problem, documentation of data, and analysis. Evaluation is the process that helps to answer such a question as "How often should men between the ages of 40 and 60 be screened for hypertension (high blood pressure)?"

By analyzing population data, epidemiologists also are able to describe diseases and determine the factors that cause them. Epidemiology is a quantitative science; it measures rates and proportions. Two commonly used rates are prevalence and incidence rates. Prevalence describes the characteristics of a given population at a specific moment in time; it is like a snapshot.

Incidence describes the rate of development of a disease in a given population over a specified time interval. Incidence offers a longer view of population dynamics, like a video, as opposed to the snapshot offered by the prevalence rate. Epidemiologists also analyze such other rates as morbidity (disease-related illness) and mortality (death).

Public health practitioners rely on the findings of epidemiologists to develop health services, allocate resources, and determine standards of care. The results of epidemiological studies also influence health policy. For example, epidemiological research helps to determine how many health care professionals are needed based on population; the effectiveness of various treatments; and schedules for immunization or screening.

Viewpoints

Historically, public health disease prevention activities focused primarily on sanitation (also referred to as environmental health) and hygiene. Public health measures aimed to ensure the safety of food and water supplies, and to prevent transmission of communicable (capable of being transmitted) diseases. In some developing countries, these same basic public health problems, such as adequate food supplies and potable (fit to drink) water, continue to threaten health and longevity.

During and after World War II, such advances in medicine as the development of antibiotics, cardiac surgery, and physical rehabilitation changed the emphasis of public health in the United States. Federal, state, and local governments enacted legislation to protect public health. Federal laws aimed at safeguarding public health. Major regulations passed during the twentieth century include:

• the 1938 Food, Drug and Cosmetic Act, which bans distribution of unsafe products and prohibits false advertising
• the 1972 Clean Water Act, which forbids release of pollutants into rivers, streams, and waterways
• the 1974 Safe Drinking Water Acts, which established standards for safe drinking water
• the 1976 Resource Conservation and Recovery Act, which stipulates the safe storage, transport, treatment and disposal of hazardous waste materials
• the 1990 Clean Air Act, which reduced industrial discharge or emission of pollutants into the air and set standards for vehicular emissions

Today, public health practitioners continue to work to prevent disease. However, their efforts are often directed to addressing such social issues as access to health care, and promoting such lifestyle changes as smoking cessation, responsible sexual behavior, and violence prevention.

Frequently, public health professionals must work cooperatively with persons in other disciplines to achieve health promotion objectives. For example, public health practitioners may work with educators and schools to