Predicting current and future distribution of West Nile disease in Tunisia

摘要

West Nile Disease (WND) is an emerging infectious vector borne disease. Culex pipiens is the mostimplicated mosquito species in the transmission of WNV in Tunisia. The spatial distribution of thisdisease has continued to expand in Tunisia since the first epidemic in 1997, while the existing knowledgeof environmental factors triggering such events continues to be rather poor. Based on the geographicallocations of human WND cases and using ecological factors as predictors, the MaxEnt model wasdeveloped to identify environmental factors influencing C. pipiens competence. Potential areas at highrisk of WND occurrence under current and future climate background are determined. The keyenvironmental factors affecting vector competence and WND occurrence were the minimum temperatureof the coldest quarter and precipitation in the warmest and driest quarter. The risk prediction mapssuggested that north-eastern, the eastern and southern coast and oasis areas of Tunisia are potential areasat high risk of WND. Identifying potential environmental factors that influence WND occurrence inTunisia is the first step for the implementation of a statistically rigorous system for real-time alert andprediction of WND. The potential high risk of WND areas are distributed widely in Tunisia. Theepidemiological surveillance system should be enhanced in these high risk regions.