of Health and Human Services s Abstract Internet access and use of georeferenced public health information for GIS application will be an important and exciting development for the nation's Department of Health and Human Services and other health agencies in this new millennium. Technological progress toward public health geospatial data integration, analysis, and visualization of space-time events using the Web portends eventual robust use of GIS by public health and other sectors of the economy. Increasing Web resources from distributed spatial data portals and global geospatial libraries, and a growing suite of Web integration tools, will provide new opportunities to advance disease surveillance, control, and prevention, and insure public access and community empowerment in public health decision making. Emerging supercomputing, data mining, compression, and transmission technologies will play increasingly critical roles in national emergency, catastrophic planning and response, and risk management. Web-enabled public health GIS will be guided by Federal Geographic Data Committee spatial metadata, OpenGIS Web interoperability, and GML/XML geospatial Web content standards. Public health will become a responsive and integral part of the National Spatial Data Infrastructure.
INTRODUCTIONGIS deployment through the Internet (also World Wide Web, Web) is a relatively new technological development. The remarkable increase in use of the Internet is creating new standards, and challenges, for the efficient use of Web-based geospatial applications (56). Challenges include spatial scale, size of data files, data compression and transmission, and other conditions for the extensive use of GIS functionality. For public health applications, geospatial databases created for the Web will have the added requirements to (a) meet confidentiality safeguards to insure the anonymity of the individual from disclosure (23b, 52) and (b) insure compliance with Section 508 of the Rehabilitation Act Amendments to make complex graphical and mapping files accessible to visually impaired users (28). GIS 1 The U.S. Government has the right to retain a nonexclusive, royalty-free license in and to any copyright covering this paper. Prior to the Internet, data "stovepipes" or data storage silos were characteristic of public health and other government agencies (103). Gaining access to data holdings, especially geographic or geospatial data, was a rigorous process for all but the most knowledgeable users. The Internet is breaking down this stovepipe legacy. Accelerating the transformation at the highest levels of policy making is the growing recognition that cost-effective development of, and access to, geospatial information are essential to the successful operation of government and the nation (5).The federal government now supports the premise that digital geospatial data constitute a capital asset (32). That is, the return on geospatial investment can be highly cost-effective through the one-time development of geospatial data and the subseq...