• Highly infectious after aerosolization
• Infectious dose can be as low as 1-10 organisms
• Risk of person-to-person transmission depends on virus

Incubation period is 4 - 21 days, depending on virus. Clinical presentation would vary by viral agent; however, dominant clinical features of all are a consequence of microvascular damage and changes in vascular permeability. Fever, myalgia, and prostration may evolve to shock, generalized mucous membrane hemmorhage, and neurologic, hematopoietic, or pulmonary involvement.


Viral isolation should be handled in a biosafety level 3 or 4 facility and may take 3-10 days. Elisa or reverse transcriptase PCR available for most VHF viruses. An isolation room with contact precautions is necessary for those infected.

Ribavirin may be helpful for congo-crimean hemmorhagic fever or arenaviruses. Licenced vaccine only available for Yellow Fever.