Rotating model of a chikungunya virus, cut away to show its internal structure. The chikungunya virus is made up of proteins arranged in a symmetrical structure around its genetic material. Its capsid is made up of 240 proteins, grouped into 12 pentamers (red pentagons) and 30 hexamers (yellow hexagons) of five and six proteins each. The capsid contains the genetic material, which is single-stranded positive sense RNA. Surrounding the capsid are spikes of a trimeric glycoprotein, which facilities viral entry into its host cells. This virus causes chikungunya disease, which causes a high fever and long-lasting joint pain. It is transmitted by the bites of Aedes aegypti and A. albopictus mosquitoes, and has been found in Africa, Asia, Europe and the Americas.