The Centers for Disease Control and Prevention offers reference materials and information on:
US Department of State
Travel Warnings are issued when the State Department recommends that Americans avoid a certain country.
Consular Information Sheets are available for every country of the world with information on such matters as health conditions, crime, unusual currency or entry requirements, areas of instability, and the location of the nearest U.S. embassy or consulate in the subject country.
Smart Traveler Enrollment Program (STEP) is a free service provided by the U.S. Government to U.S. citizens who are traveling to, or living in, a foreign country. STEP allows you to enter information about your upcoming trip abroad so that the Department of State can better assist you in an emergency. STEP also allows Americans residing abroad to get routine information from the nearest U.S. embassy or consulate.