What is Public Health?
"Public health is organized community efforts to ensure conditions in which people can be healthy. Activities that society undertakes to prevent identify, and counter threats to the health of the public."

Source: Introduction to Public Health by Mary Jane Schneider, PhD, 2000
The key word in the above definition is public. In contrast to physicians and other healthcare
professionals, who exam, diagnose, and treat one patient at a time, public health workers are concerned with population-based medicine. In a typical health department, you can see a broad range of services being offered such as:

Childhood and adult immunizations
Physical examinations
Health screenings
Health education and prevention programs
Home visits for the chronically-ill or at-risk patients
Teen pregnancy and family planning
Much, much more...

The most intriguing part of the public health system (in my opinion) is use of proactive services, which prevent disease before it happens. These areas focus on specific disciplines in a typical health department:

Communicable disease
Environmental health
Vital statistics (birth and death rates, etc.)
Bioterrorism
County/state health assessments
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