Chikungunya ( ; Makonde for "that which bends up") is an infection caused by the chikungunya virus. The disease features the sudden onset of fever two to four days after exposure. The fever usually lasts two to seven days, while accompanying joint pains typically last weeks or months but sometimes years. The mortality rate is a little less than 1 in 1000, with the elderly or those with underlying chronic medical problems most likely having severe complications.