Silent victories

Over the century, America's public health system grew dramatically, employing science and political authority in response to an increasing array of health problems. As the disease burden of the old scourges of infection, perinatal mortality, and dietary deficiencies began to life, public health's mandate expanded to take on new health threats, such as those resulting from a changing workplace, the rise of the automobile, and chronic and complex conditions caused by smoking, diet and other lifestyle and environmental factors.