The Critical Role of Partnerships The challenge of emerging infections is broad, therefore, an effective response will require the efforts of multiple agencies and organizations and strong ties among public health, clinical, and biomedical research professionals. Although CDC maintains primary responsibility for national surveillance and rapid investigation of emerging threats, it shares other responsibilities with many organizations in regard to research and implementation of control measures. Cooperative efforts between CDC and its partners have helped address such infectious disease threats as nosocomial infections, influenza, listeriosis, streptococcal and pneumococcal disease, ehrlichiosis, and HPS (see Boxes). CDC has also cooperated with numerous representatives from academia, clinical practice, private industry, health departments, and other federal agencies in the development of the National Vaccine Plan and the National Action Plan to Combat Multidrug-Resistant Tuberculosis. Partnerships at the federal level have been helpful in confronting other infectious diseases of public health importance in the United States. For example, CDC and NIH, working closely with ASTPHLD, developed improved diagnostic tests for Lyme disease and various fungal infections. CDC has also worked closely with FDA and USDA in controlling emerging foodborne illnesses such as listeriosis,90,96 Salmonella enteritidis infection,34 and E. coli O157:H7 infection.43,44 Recent CDC collaborations with EPA have been instrumental in recognizing and controlling waterborne outbreaks of giardiasis and cryptosporidiosis in several states. In addition, CDC has often joined forces with USDA and DOD to control or prevent vector-borne infectious disease threats, such as eastern equine encephalitis and St. Louis encephalitis. Such cooperative efforts were used successfully to address potential mosquito-borne illness following Hurricane Andrew in Florida and Louisiana in 1992.97 Clear, well-established lines of communication and responsibility between appropriate personnel in federal agencies, such as CDC, NIH, EPA, FDA, USDA, DOD, and others, are essential to the development of efficient, cost- effective prevention and control strategies. Such links help eliminate costly duplication of effort and focus limited federal resources on the early recognition and timely control of new infectious disease problems. Effective public health policy results from interaction, cooperation, and coordination among a wide range of public and private organizations and individuals. Particularly critical to this process are CDC's partnerships with state and territorial health departments; other federal agencies; professional organizations; academic institutions; private health care providers; health maintenance organizations and health alliances; local community organizations; private industry; and international partners, including WHO and international service organizations and foundations. Each of these partners will play an integral role in the cooperative efforts required to safeguard the public's health from emerging infectious disease threats.