Viral hemorrhagic (hem-uh-RAJ-ik) fevers are infectious diseases that interfere with the blood's ability to clot. These diseases can also damage the walls of tiny blood vessels, making them leaky. The internal bleeding that results can range from relatively minor to life-threatening.

Some viral hemorrhagic fevers include:

  • Dengue
  • Ebola
  • Lassa
  • Marburg
  • Yellow fever

These diseases most commonly occur in tropical areas of the world. When viral hemorrhagic fevers occur in the United States, they're usually found in people who've recently traveled internationally.

Viral hemorrhagic fevers are spread by contact with infected animals, people or insects. No current treatment can cure viral hemorrhagic fevers, and immunizations exist for only a few types. Until additional vaccines are developed, the best approach is prevention.

Mar. 05, 2013