West Nile Virus (WNV): One-Health and Eco-Health Global Risks.

West Nile virus (WNV) is an important zoonotic pathogen belonging to the Flaviviridae family, which is endemic in some areas and emerging in others. WNV is transmitted by blood-sucking mosquitoes of the genus Culicoides, Aedes, and Anopheles, and the infection can cause different clinical symptoms. The most common and benign illness in humans is West Nile fever (WNF), but a lethal neurological disease (WNND), related to the neuro-invasiveness of WNV lineage 2, represents the highest health risk of WNV infection. The neuro-clinical form is recognized in mammals (land and cetaceans), particularly in humans (elderly or immunosuppressed) and in horses, avian species, and wildlife animals ranging free or in a zoological setting. This review highlights the most relevant data regarding epidemiology, virology, pathogenesis and immunity, clinical signs and differential diagnosis, pathology and imaging, histopathology and gross pathology, economic impact, influence of climate change, and surveillance of WNV. Climate change has favored the wide spread of WNV in many areas of the globe and consequent One-Health and Eco-Health emergencies, influencing the health of human beings, animals, and ecosystems.