Ebola, smoking, and mission creep at the CDC: controlling contagious diseases is just one of many items on the agency's to-do list.

• Author: Sullum, Jacob
• Position: Columns - United States Centers for Disease Control and Prevention - Column

BEFORE TOM FRIEDEN became director of the U.S. Centers for Disease Control and Prevention (CDC) in 2009, his two nemeses were tuberculosis and smoking. Although both are commonly described as threats to "public health," they differ in ways that may help explain the CDC's stumbles in dealing with Ebola.

Tuberculosis, which Frieden helped control in New York City and India as a CDC epidemiologist, is a contagious, potentially lethal disease. Smoking, which Frieden targeted as New York City's health commissioner, is a pattern of behavior that increases the risk of disease.

That distinction matters to people who reject paternalism as a justification for government action. We believe the use of force can be justified to protect the public from TB carriers but not to protect smokers from their own choices.

Frieden rejects that distinction. Fie sees the goal of public health as minimizing morbidity and mortality, even when they arise from voluntarily assumed risks, and he does not hesitate to rely on state power in pursuing that mission. For him, public health means quarantining and treating disease carriers, but it also means imposing heavy taxes on cigarettes, banning trans fats, and forcing restaurants to post calorie counts.

This understanding of public health is an open-ended license for government meddling. It is also a recipe for mission drift, as reflected in the CDC's ever-widening agenda.

"As the scope of CDC's activities expanded far beyond communicable diseases," explains CDC historian Elizabeth Etheridge, "its name had to be changed." Beginning as a branch of the Public Health Service charged with malaria control in Southern states during World War II, it became the Center for Disease Control in 1970, the Centers for Disease Control in 1981, and the Centers for Disease Control and Prevention in 1992.

Today the CDC's mission includes pretty much anything associated with disease or injury. In 2013 The New York Times mentioned the agency more than 200 times. Communicable diseases accounted for 54 of those references, but the topics also included smoking, drinking, electronic cigarettes, obesity, diet, suicide, addiction, driving, sports injuries, contraception, economic inequality, domestic...