Rift Valley Fever (RVF):
Clinical, epidemiologic, and preventive overview—2025 Update

Rift Valley fever (RVF) is a mosquito-borne viral zoonosis that affects humans and livestock, primarily in Africa, with occasional outbreaks in the Middle East. The following summarizes current knowledge on clinical features, epidemiology, transmission, prevention, therapy, and vaccine development. Clinical features: Most human infections are mild and self-limited, presenting with fever, headache, myalgia, back pain, dizziness, anorexia, and photophobia. Severe disease occurs in 1%–2% of cases, manifesting as hemorrhagic fever (with hepatic dysfunction and bleeding), encephalitis with neurological symptoms (confusion, seizures, coma), or ocular complications (retinal lesions and potential vision loss). Case-fatality rates for the hemorrhagic form can reach 50%, and encephalitis often results in long-term neurological sequelae. Epidemiology: As of late 2025, active outbreaks are reported in northern Senegal, with human fatalities and major livestock losses. RVF remains endemic and epidemic across sub-Saharan Africa, with periodic outbreaks in Egypt, the Arabian Peninsula, and Indian Ocean islands. Transmission cycles involve enzootic maintenance in livestock...