FAO and IGAD warn El Niño raises risk of Rift Valley fever outbreaks in Eastern Africa
The UN Food and Agriculture Organization (FAO) and the Intergovernmental Authority on Development (IGAD) are urging Eastern African countries to step up surveillance, as El Niño-driven heavy rain and flooding raise the risk of Rift Valley fever.
The Food and Agriculture Organization of the United Nations (FAO), based in Rome, and the Intergovernmental Authority on Development (IGAD), a regional body of Eastern African states, are urging countries in the region to strengthen preparedness and disease surveillance. The reason is heavy rainfall and flooding linked to El Niño, a climate pattern now approaching record strength, which raise the risk of Rift Valley fever (RVF) outbreaks.
RVF is an acute viral disease affecting livestock, including sheep, goats, cattle, buffaloes and camels, and it can also infect humans. The virus is spread mainly by mosquitoes, while the movement of infected animals can help it reach new areas. People can also become infected through direct contact with infected animals or animal products.
Why the risk is rising
Heavy rain and floods expand mosquito breeding sites and may disrupt veterinary services. Current El Niño conditions are comparable to those of 1997–98, when one of the largest recorded RVF epidemics and epizootics struck Eastern Africa.
Ethiopia, Kenya, Somalia, South Sudan, Tanzania and Uganda are assessed as facing the highest risk. Risk is also growing in Burundi and Rwanda, while lower but increasing risks exist in the Comoros, northern Madagascar, the Department of Mayotte, south-western Saudi Arabia and western Yemen.
In their alert, FAO and IGAD call on countries to strengthen risk-based surveillance, pre-position vaccines and essential supplies, and improve coordination across sectors and borders through a One Health approach. The alert is issued through FAO's EMPRES, its global early warning and prevention system for animal health.
Forecasts
Above-average rainfall and flooding are expected across most of Eastern Africa. The heaviest rain is forecast for southern Ethiopia, Kenya, and central and southern Somalia, where there is a greater than 90 percent probability of more than 400 mm. Drier-than-normal conditions are expected in southern Sudan and Southern Africa.
According to the October 2026 forecast of FAO's RVF Early Warning Decision Support Tool, conditions suitable for transmission are expected to increase across much of the region between October 2026 and January 2027. Tanzania currently has the largest suitable area, followed by Ethiopia, Kenya, South Sudan and southern Sudan. New suitable areas have appeared in southern Somalia, Rwanda and Burundi and are expected to expand further, including in Uganda.
The tool combines satellite data, climate forecasts, disease surveillance information and expert analysis to identify areas at elevated outbreak risk up to three months in advance.
