Epidemic hemorrhagic fever describes a collection of syndromes of acute febrile disease in which shock and hemorrhage are the most obvious characteristics.  Their short incubation periods and mode of transmission have raised great concern in the general public. While some viral hemorrhagic fevers or VHFs can cause severe symptoms, other VHFs do not cause severe illness or death.  Viral hemorrhagic fevers are generally characterized by fever, muscle aches, fatigue, weakness, and dizziness.  More serious cases may involve bleeding from body orifices, bleeding under the skin or bleeding in internal organs.  However, blood loss is rarely the cause of death in these cases.
    Secondary human transmission rates are extremely high for VHFs, so universal precautions are highly recommended for those caring for infected individuals.  Masks, gowns, and glove protection help to limit contact with contaminated blood or tissue.  Drawing of blood should be limited to prevent aerosolation of the pathogen.

    VHFs are caused by viruses of four distinct families: arenaviruses, filoviruses, bunyaviruses, and flaviviruses.  Each of these families share a number of features:

        -They are all RNA viruses, and all are covered, or enveloped, in a fatty (lipid) coating.
        -Their survival is dependent on an animal or insect host, called the natural reservoir.
        -The viruses are geographically restricted to the areas where their host species live.
        -Humans are not the natural reservoir for any of  these viruses.   Humans are infected  when they
            come into contact with infected hosts. However, with some viruses, after the accidental
            transmission from the host, humans can transmit the virus to one another.
        -Human cases or outbreaks of hemorrhagic fevers caused by these viruses occur sporadically and
            irregularly. The occurrence of outbreaks cannot be easily predicted.
        -With a few noteworthy exceptions, there is no cure or established drug treatment for VHFs.

 
 

Viral Hemorrhagic Families

Arenaviruses
Filoviruses
Bunyaviruses
Flaviviruses

References:
Centers for Disease Control
 World Health Organization