The word “chikungunya” was first used by the indigenous people of Southern Province, Tanganyika Territory, in reference to a disease which afflicted them in epidemic form in 1952—1953. The disease was characterized mainly by a sudden onset, fever, rash, and joint pains. First indications of this were reported from Uganda in 1958 when chikungunya (CHIK) virus was isolated from the primatophilic Ae. africanus collected in the forest canopy and from a mosquito catcher who may have been infected in the canopy. The initial antigenic classification of CHIK virus was based on reactions obtained with hemagglutination-inhibition and complement-fixation tests as well as neutralization tests in mice particularly to Mayaro and Semliki Forest viruses. CHIK is a feverish illness characterized by sudden onset, chills, flushed face, nausea, vomiting, backache, headache, photophobia, lymphadenopathy, arthralgia, and rash. CHIK appears to have spread to other parts of the world from Africa to cause pandemics in both the American and Asian tropics.