RIFT VALLEY FEVER - Predictive tool
Historical ecological information has shown that pronounced periods of RVF virus activity in Africa have occurred during periods of heavy, widespread and persistent rainfall now associated with El Niño events (since it creates propitious conditions to the multiplication of the mosquitoes, vectors of the disease).Vegetation responds to increased rainfall and variation can be easily measured by satellite.
At FAO headquarters, near real-time climatic data such as rainfall estimates and NDVI indices obtained from Artemis (Africa Real time Environmental Monitoring Sysyem, established by FAO in 1998) are collected and processed using the FAO developed Windisp 3.0 software. Risk maps are produced by calculating vegetation index and rainfall anomalies comparing current conditions to long-term mean conditions. A major partner institution is the NASA Goddard Space Flight Center (USA), which produces RVF monthly risk maps based on the persistence of Vegetation index (NDVI) anomalies.
Thanks to those tools, a possible RVF activity in the horn of Africa had been predicted since November 2006 (read EMPRES Watch).
