Study of the pathogenesis of Usutu virus infection in ovo and in vivo

Usutu virus (USUV) is a mosquito-borne flavivirus, closely related to the West Nile virus (WNV). Similar to WNV, USUV may cause infections in humans, with occasional, but sometimes severe, neurological complications. Further, USUV can be highly pathogenic in wild and captive birds and its circulation in Europe has given rise to substantial avian death. Adequate study models of this virus are still lacking but are critically needed to understand its pathogenesis and virulence spectrum. In this thesis, we used natural infection cases and experimentally infected animals (chicken embryos, canaries and immunocompetent mice) to fill some gaps in our knowledge regarding the pathogenesis and epidemiology of USUV in Belgium.