Rift Valley Fever is an infection caused by the RVF virus belonging to the the Bunyaviridae family. It is a zoonosis – an animal disease that can spread to humans – that primarily affects livestock such as cattle, sheep, goats, buffalo, and camels. Humans become ill with Rift Valley Fever when they are bitten by infected mosquitoes, blood feeding flies, or come into contact with infected animal blood, fluid, or tissues through a skin lesion or inhaling infected air droplets from animals. No human to human transmission of the RVF virus has been reported.
The infection is endemic in northern, eastern, and southern Africa and outbreaks have also occurred in the Arabian Peninsula. There is greater risk for campers or persons spending a significant time outdoors. RIft Valley Fever is an occupational risk for veterinarians, herders, and abattoir workers.
In some cases the infection is asymptomatic – persons do not exhibit symptoms. However, those who show symptoms get ill 2 to 6 days after exposure to the virus with flu-like symptoms, including sudden fever, muscle and joint pain, and headache. Sensitivity to light, neck stiffness, vomiting and loss of appetite are also common. Most patients recover 4 to 7 days later, but some end up with one or more severe forms of the infection: Ocular syndrome (legions to the retina causing possible vision loss), meningoencephalitis (brain swelling causing memory loss, hallucinations, and convulsions) and /or haemorrhagic fever (uncontrolled bleeding and possible liver damage).
There is no preventive medication or vaccine against Rift Valley Fever.
Rift Valley Fever virus images, life cycle, and distribution maps
Health risk description last reviewed: September 14, 2016
Country information last updated: April 13, 2018