"We provide leadership and bring many partners together to protect the world from infectious diseases. Our aim is to detect, prevent, and control infectious diseases from spreading, whether they are naturally occurring, unintentional, or the result of terrorism. We achieve this by working here and abroad to establish safe and high-quality healthcare, laboratory services, surveillance systems, and networks that share vital information about infectious diseases. We focus on 1) Specific populations, such as immigrants, refugees, travelers, patients, and healthcare providers. 2) Specific places, including U.S. and international borders and places where newly emerging diseases threaten the world population's health. 3) Specific settings, such as laboratories, hospitals, outpatient clinics, nursing homes, dialysis centers, and other healthcare settings."
Centers for Disease Control and Prevention: http://www.cdc.gov/