[West Nile virus: in France again, in humans and horses]

West Nile virus (WNV) is a common arbovirosis, transmitted by mosquitoes mainly Culex. WNV is commonly responsible for equine epizootics and epidemics in humans in sub-Saharan Africa. It has been occasionally described in Southern Europe and in some Mediterranean countries. Since 1994, WNV clinical aspects seem to change with an increase of central neurological involvement and a higher mortality, especially among people older than 50 years. In 1999, WNV reached New York, being responsible for severe clinical manifestations. It spread all over North America in less than four years Four (only four states of the United States are free). As a consequence of an equine epizootic in Camargue in 2000, French medical authorities settled a survey of the WNV circulation in the South of France. During 2003, this efficient action led to identify 6 human cases in a formerly WNV-free French Mediterranean coast, but not in Camargue.