West Nile Fever: A Challenge in Sahelian Africa

West Nile fever is an arthropod-borne viral disease of public health importance transmitted by mosquitoes from the genus Culex. Birds are the main hosts/reservoirs of West Nile virus (WNV; Flaviviridae, Flavivirus) and ensure its spread worldwide toward migration. The WNV is continuously spreading across the world with significant health and economic impact in human and animals, especially in newly infected areas where many human and animal losses are reported. However, in most of the African countries where the disease is endemic, no or few human or animal cases are reported in contrast with the high prevalence of the disease and the recurrent circulation of the virus. These gaps could be related to the fact that clinical signs are similar to those of dominant pathologies in human or equine encephalitis in animal health allowing to a misdiagnosis.