Environmental Biosurveillance for Epidemic Prediction: Experience with Rift Valley Fever

摘要

Despite established links between climate and infectious disease activity, few biosurveillance systems use climatic data to forecast epidemics. The El Nino/Southern Oscillation (ENSO) affects weather worldwide and in East Africa is associated with flooding and Rift Valley fever, a mosquito-borne viral disease of economically important livestock and humans. Following a regional ENSO-associated outbreak in 1997-1998, several agencies created a system to forecast RVF using satellite-based monitoring of ENSO and other climatic phenomena. The system generated 5 alerts since 2005. Following 3, in South Africa (2008), Sudan (2007), and East Africa (2006), RVF occurred in high-risk areas (no other RVF outbreaks were reported in monitored areas). Alerts for the Arabian Peninsula (2005) and Sudan (2005) were not followed by RVF reports, though the latter preceded a large Yellow Fever epidemic. Future directions for the system include decision analysis to guide public health interventions and extension to other climate-associated risks.