There is a wealth of public health data and statistics on this page. Access FASTSTATS A-Z - an alphabetical listing of statistics on topics of public health importance, Health, United States (HUS) - the annual report on trends in health statistics, Health-E Stats - a Web-only release of selected statistics and Vital Records.
Public Health Data Warehouse with a number of health data including NHANES, NHCSand SLAITS. Many files and publications are available electronically. This site is only one example of the statistical information available from the federal government - be sure to check out the FedStats site listed above for numerous other sources.
From the Centers for Disease Control, CDC WONDER is "a general-purpose public health information and communications system. CDC WONDER provides query access to about 40 text-based and numeric databases. Numeric databases can provide, for example, the numbers and rates of sexually transmitted diseases, cancer cases, or deaths in the United States. Users can request data for any disease and demographic group, by submitting ad hoc queries against available data sets."
U.S. Department of Health and Human Services pages with disaster management information. The pages include web pages, journals, databases and MeSh terms for searching PubMed for disaster medicine and preparedness.