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Source http://health.usf.edu/publichealth/definition.html
Even professionals in the field struggle to define public health precisely. It has been called the "invisible profession" because people don't hear much about it until a disaster occurs. Then, public health experts are in the spotlight, calling on their understanding of the way the physical and social worlds work to save lives. Public health professionals are part of an ongoing system that protects people from diseases and encourages them to change harmful behaviors. Public health has been increasingly concerned with targeted prevention programs aimed at specific problems that disproportionately affect minority and economically disadvantaged groups. With its focus on health promotion and disease prevention, public health provides a foundation for our health care system that ultimately means lower health care costs.
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