Clinical Information

Chikungunya virus (ChikV) is a single-stranded RNA alphavirus and a member of the Togaviridae family of viruses. The name Chikungunya is derived from the language of the Makonde ethnic groups in southeast Africa and means "that which bends" or "stooped walk." This is in reference to the hunched-over appearance of infected individuals due to the characteristically painful and incapacitating arthralgia caused by the virus. ChikV is endemic throughout Africa, India, and, more recently, the Caribbean islands. In 2014, the first case of autochthonous, or local transmission, in the US occurred in Florida.

Humans are the primary reservoir for ChikV, and Aedes species mosquitoes are the primary vectors of transmission. Unlike other mosquito-borne viruses, such as West Nile and dengue viruses, the majority of individuals exposed to ChikV become symptomatic. Severe manifestations are most often observed in individuals at the extremes of age and in those with suppressed immunity. Following exposure to ChikV, individuals develop lasting immunity and protection from reinfection.

Prior to development of symptoms, the incubation period ranges, on average, from 3 to 7 days. Infected patients typically present with sudden-onset high fever, incapacitating joint pain, and often a maculopapular rash lasting anywhere from 3 to 10 days. Notably, symptom relapse can occur in some individuals 2 to 3 months following resolution of initial symptoms. Currently, there are no licensed vaccines and treatment is strictly supportive care.