Detection and molecular characterization of West Nile Virus from wild bird in Serbia 2018

Abstract

West Nile fever is zoonotic arthropod-borne disease affects birds, humans and horses. Causative agent is virus, which belongs to family Flaviviridae, genus Flavivirus. Up to today nine genetic lineages were described. It’s been detected in Africa, Europe, Australia, the Middle East, North, South and Central America and West Asia. Virus circulates between mosquitoes and birds, whereas humans and horses are dead end hosts. The presence of clinical symptoms in birds varies from absence to fatal neurological symptoms. Horses and humans can be affected, with signs of encephalitis and encephalomyelitis. Migratory birds are responsible for the widespread distribution of virus. The aim of this study is identification and molecular characterization of West Nile virus detected in dead hooded crow (Corvus cornix) in Serbia during the monitoring of the disease in mosquitoes and wild birds, in July 2018. In order to determine genotype of the virus, sequencing of the envelope gene was performed. Homology of obtained nucleotide sequence with known isolates identified in Serbia and neighbour countries in previous years was assessed. The phylogenetic analysis showed that this isolate belongs to lineage 2 WNV, and showed 99,92% homology with sequences of West Nile virus isolates 341/2010-Greece, Serbia/Novi Sad 24/2013, Vojvodina_2013_03 and Nea Santa-Greece-2010. Results obtained during the monitoring of WNV and consequential phylogenetic analysis are important for the understanding of WNV molecular epizootiology and could be used for the determining the origins and geographical distribution of the virus.