Journal de virologie et de recherche antivirale

First Identification of Orungo Virus (Orbivirus) from a Febrile Patient in South-Eastern Senegal, 2015

Martin Faye, Arame Ba, Yakhouba Kane, Andre Pouedewou Bedekelabou, Mamadou Diop, Moussa Moise Diagne, Gamou Fall, Oumar Faye, Amadou Alpha Sall and Ousmane Faye

Orbiviruses are of medical interest for humans and livestock worldwide. We isolated a novel Orungo virus strain from in a febrile patient living in Southeastern Senegal. The full-length genome was determined using MiSeq next-generation sequencing and the phylogenetic relationship to other orbivirus groups was analyzed. Inoculation experiments in mammalian Vero cells and mice were conducted and a specific real time reverse transcription-polymerase chain reaction assay was developed.

This is the first isolation of Orungo virus in a human in Senegal in addition to the prototype strain. This new characterized Orungo virus genome presents ten segments with the typical genomic organization of orbiviruses. However, important amino acid gaps were identified on it VP1 and VP3 segments. Phylogenetic analysis confirms that this Senegalese Orungo isolate is closely related to Culicoides-borne orbiviruses. In addition, this isolate is able to infect mammalian Vero cells and is lethal for mice when inoculated intra-cerebrally. The developed reverse transcription-polymerase chain reaction assay can be used for rapid and specific detection of Orungo virus.

This study would be helpful not only for future genomic studies to understand the biological and pathogenic properties of Orungo virus, but also for better understanding of its evolutionary history of orbiviruses and assessment of their potential public health impact.