The future of national public health surveillance in the United States.

Public health surveillance systems should have the capacity to collect and analyze data, disseminate data to public health programs, and regularly evaluate the effectiveness of the use of disseminated data. Unfortunately, in the United States, systems of public health surveillance are fragmented and do not adequately address either current or new potential challenges to public health. This commentary addresses components of any effort toward a national public health surveillance system and highlights examples of these components in state and national surveillance developments.