Infection control an health care epidemiology is the discipline concerned with preventing the spread of infections within the health-care setting. As such, it is a practical (rather than an academic) sub-discipline of epidemiology. It is an essential (though often underrecognized and undersupported) part of the infrastructure of health care. Infection control and hospital epidemiology are akin to public health practice, practiced within the confines of a particular health-care delivery system rather than directed at society as a whole.