It is a mosquito-borne virus of the family Flaviviridae. There are four serotypes of dengue viruses, DEN-1, DEN-2, DEN-3, and DEN-4. Dengue virus type 3 genotype III (DENV3/III) is associated with increased number of severe infections when it emerged in the Americas and Asia.
Dengue is found in tropical and subtropical climates worldwide, mostly in urban and semiurban areas. People of all ages who are exposed to infected mosquitoes are possible victims of dengue fever. The disease occurs most often during the rainy season in tropical countries in Asia and [South America, with high numbers of infected mosquitoes.
Signs and symptoms may include severe headache; retro-orbital pain; muscle, joint, and bone pain; macular or maculopapular rash; and minor hemorrhagic manifestations, including petechiae, ecchymosis, purpura, epistaxis, bleeding gums and hematuria.