Viral Hemorrhagic Fevers, Biological Weapon

The viral hemorrhagic fevers are a group of human illnesses caused by RNA viruses of different families:

  • The Filoviridae, which consists of Ebola and Marburg viruses

  • The Arenaviridae, including Lassa fever

  • Argentine and Bolivian hemorrhagic fever viruses

  • The Bunyaviridae, including various members from the Hantavirus genus

  • Congo-Crimean hemorrhagic fever virus from the Nairovirus genus

  • Rift Valley fever from the Phlebovirus genus

  • Flaviviridae, such as Yellow fever virus

  • Dengue hemorrhagic fever virus

  • Others.

The viruses may be spread in a variety of ways, and for some there is a possibility that humans could be infected through a respiratory portal of entry. Although evidence for weaponization does not exist for many of these viruses, many are included in this handbook because of their potential for aerosol dissemination or weaponization, or likelihood for confusion with similar agents which might be weaponized.


VHFs are fever-causing illnesses which can be complicated by easy bleeding, low blood pressure, and even shock (a blood pressure usually too low to support life for long). There may be flushing of the face, chest, and edema. Constitutional symptoms such as malaise, myalgias, headache, vomiting, and diarrhea may occur in any of the hemorrhagic fevers.


The only licensed VHF vaccine is for yellow fever. Prophylactic (given before the problem occurs) ribavirin may be effective for Lassa fever, Rift Valley fever, CCHF, and possibly HFRS.