Rift Valley fever is a high-consequence pathogen of people and animals found throughout Africa and parts of the Middle East. Rift Valley fever virus is mosquito-borne and is a classic example of the multi-faceted intersection of human and animal health and vector ecology that characterize the One Health aspects of zoonotic arboviruses.
First identified in the 1930s, RVF outbreaks can be severe, with multiple large-scale outbreak (>50,000 to 200,000 cases) occurring periodically across Africa. The rapid and sudden development of tens of thousands of human cases and the widespread agricultural impact on potentially millions of livestock have challenged public health infrastructures to cope with the magnitude of these outbreak emergencies. Lethality among livestock animals is very high (30-90%) and is typically followed a few weeks later by explosive incidence of human cases due to transmission from infected mosquitoes or contact with virus contaminated livestock tissues, fluids, or aborted materials. Among severe human cases, RVF can manifest clinically as hepatitis, retinitis, delayed onset encephalitis, and a hemorrhagic syndrome with high case fatality.
Because of these devastating effects, in 2018 the World Health Organization included RVF as one of the top ten priority R&D blueprint diseases due to its potential to generate a public health emergency, with no currently approved preventive and curative solution.