Dengue is caused by Dengue virus (DENV), a mosquito-borne flavivirus. DENV is an single stranded RNA positive-strand virus of the family Flaviviridae, genus Flavivirus. This genus includes also the West Nile virus, Tick-borne Encephalitis Virus, Yellow Fever Virus, and several other viruses which may cause encephalitis. DENV causes a wide range of diseases in humans, from a self limited Dengue Fever (DF) to a life-threatening syndrome called Dengue Hemorrhagic Fever (DHF) or Dengue Shock Syndrome (DSS).