The
viral hemorrhagic (or
haemorrhagic)
fevers (
VHFs) are a diverse group of animal and human
illnesses in which
fever and
hemorrhage are caused by a
viral infection. VHFs may be caused by five distinct families of
RNA viruses: the families
Arenaviridae,
Filoviridae,
Bunyaviridae,
Flaviviridae, and
Rhabdoviridae. All types of VHF are characterized by fever and bleeding disorders and all can progress to high fever, shock and death in many cases. Some of the VHF agents cause relatively mild illnesses, such as the Scandinavian
nephropathia epidemica (a
Hantavirus), while others, such as
Ebola virus, can cause severe, life-threatening disease.