ARS | Publication request: A Rift Valley Fever Risk Surveillance System in Africa Using Remotely Sensed Data in a GIS: Potential for Use on Other Continents

Submitted to: Meeting Abstract
Publication Type: Abstract
Publication Acceptance Date: October 8, 2006
Publication Date: October 11, 2006
Citation: Linthicum, K., Anyamba, A., Chretien, J., Erickson, R.L., Small, J., Tucker, C.J., Britch, S.C., Bennett, K.E., Mayer, R.T., Schmidtmann, E.T., Andreadis, T.G., Anderson, J.F., Wilson, W.C., Freier, J., James, A., Miller, R., Drolet, B.S., Miller, S., Tedrow, C., Strickman, D.A., Barnard, D.R., Clark, G.G., Zou, L. 2006. A rift valley fever risk surveillance system in africa using remotely sensed data in a gis: potential for use on other continents. International Conference on Use of GIS in Veterinary Activities in Silvi Marina, Abruzzo, Italy on October 8-11, 2006.

Technical Abstract: Rift Valley fever (RVF) is a mosquito-borne viral disease with pronounced health and economic impacts to domestic animals and humans in much of sub-Saharan Africa (1). The disease causes high mortality and abortion in domestic animals, and significant morbidity and mortality in humans. RVF epizootics and epidemics are closely linked to the occurrence of the warm phase of the El Niño/Southern Oscillation (ENSO) phenomenon (2). We have developed a monitoring and risk mapping system using normalized difference vegetation index (NDVI) times series data derived from the Advanced Very High Resolution Radiometer (AVHRR) instrument on polar orbiting National Oceanographic Atmospheric Administration (NOAA) satellites to map areas with a potential for an RVF outbreak (3). This surveillance system operates in near-real time to monitor RVF risk on a monthly basis and offers the opportunity to identify ecoclimatic conditions associated with disease outbreaks over a large area (4). This system is an important tool for local, national and international organizations involved in the prevention and control of animal and human disease, permitting focused and timely implementation of disease control strategies several months before an outbreak. The RVF outbreak on the West coast of the Arabian Peninsula in 2000 demonstrated that other regions of the world can be at risk of the disease (5). The surveillance system developed for Africa has been modified to include the Arabian Peninsula, and can potentially be adapted to assess the risk of RVF and other arthropod-borne disease outbreaks in new ecological settings (6). We are currently developing a GIS/remotely sensed early warning system for RVF vectors in the U.S. using mosquito surveillance data collected by mosquito control and public health agencies, and climate data measured by satellites and terrestrial weather stations. The GIS predicts disease transmission patterns based on the quantitative relationship between mosquito activity and patterns of local and global climate, and identifies early warning parameters associated with elevated populations of potential RVF vectors. Linkages between climate and mosquito densities are evaluated with spatial and temporal statistics, generating risk maps to inform vector control agencies. Mosquito prediction information will be disseminated throughout the U.S., granting several months warning before conditions are suitable for elevated mosquito populations, permitting targeted implementation of mosquito control, animal quarantine and vaccine strategies in time to lessen or prevent animal and human disease. Many of the systems we develop in preparation for RVF can be laterally transferred to inform strategies against any mosquito-borne disease threat.