Rift Valley fever (RVF) is an acute viral disease that affects domestic animals (such as cattle, buffalo, sheep, goats, and camels). The disease is caused by the RVF virus, generally found in regions of eastern and southern Africa, but also in most countries of sub-Saharan Africa, Madagascar, Saudi Arabia and Yemen.

Humans may become infected through direct or indirect contact with the blood or organs of infected animals. While most human cases are relatively mild, a small percentage of patients develop a much more severe form of the disease. The uncomplicated cases are characterised by acute influenza-like illness leading to full recovery. In some patients the illness can progress to a severe form with haemorrhagic manifestations and hepatitis; possible complications include retinitis (inflammation of the retina) and encephalitis (inflammation of the brain).

Vaccination of the animals at risk is the most important way of preventing infection in humans.