CLINICAL DESCRIPTION

Viral Hemorrhagic Fever (VHF) is the collective name given to the diseases caused by ribonucleic acid (RNA) viruses from four distinct families. These diseases include Ebola Hemorrhagic Fever, Marburg Hemorrhagic Fever, Lassa fever, Hantavirus Pulmonary Syndrome, and Yellow Fever. None of these viruses occurs naturally in the United States. Symptoms vary with the disease, but often include fever, fatigue, and muscle aches. There may be bleeding, although death from blood loss is rare. Severe cases can include shock and coma. Although some types of VHFs are relatively mild illnesses, many of them can cause severe, life-threatening disease with high fatality rates.

Risk factors for these diseases include travel to certain geographic areas where these diseases may naturally occur (such as certain areas of Africa, Asia, the Middle East, and South America), handling of animal carcasses, contact with sick animals or people with the disease, and arthropod bites.

Laboratory studies represent an extreme biohazard and should be carried out only where protection against infection of the staff and community is available (BSL-4 containment).

Hemorrhagic fever viruses are among the six agents identified by the Centers for Disease Control and Prevention (CDC) as the most likely to be used as biological weapons.

CASE CLASSIFICATION

1. CONFIRMED
   
   A clinically compatible case, with or without laboratory isolation, as reported by a healthcare professional.
   
   
2. PROBABLE
   
   Not used
   
   
3. POSSIBLE
   
   Not used