Chikungunya

Chikungunya is a mosquito-borne viral disease caused by the chikungunya virus (CHIKV), an RNA virus classified within the alphavirus genus of the Togaviridae family. The disease name derives from the Kimakonde language of southern Tanzania, where it means 'that which bends up,' describing the stooped posture adopted by patients experiencing severe joint pain. CHIKV was first isolated and characterized in the United Republic of Tanzania in 1952, with subsequent identification in other African and Asian countries during the following decades.

Chikungunya infection presents with an abrupt onset of high fever typically exceeding 39°C, accompanied by severe symmetric polyarthralgia affecting multiple joints of the arms and legs. The joint pain has been described as excruciating and is frequently debilitating, often lasting several days but potentially persisting for weeks, months, or even years in some patients. Additional manifestations include muscle pain, headache, back pain, nausea, fatigue, and maculopapular rash, with approximately half of symptomatic individuals developing rash. While most patients recover within one week, the very young, elderly, and those with underlying health conditions are at elevated risk for severe disease. An estimated 17-40% of infections may be entirely asymptomatic.

Chikungunya virus was first identified in Tanzania in 1952 and remained confined to African and Asian contexts for several decades, with urban outbreaks first documented in Thailand in 1967 and India during the 1970s. A significant epidemiological shift occurred beginning in 2004, when outbreaks became substantially more frequent and geographically widespread, attributable partly to viral adaptations facilitating enhanced transmission by Aedes albopictus mosquitoes and introduction into immunologically naive populations. The first locally mosquito-transmitted cases in the Americas were reported in late 2013, subsequently generating large outbreaks across most countries in the region. The virus has now been identified in over 110 countries across Asia, Africa, Europe, and the Americas. Transmission dynamics vary by region: islands with high population exposure and subsequent immunity may experience interruption of transmission for several years, whereas transmission persists in areas where large proportions of the population remain susceptible.

Chikungunya virus is transmitted to humans through the bites of infected female mosquitoes, principally Aedes aegypti and Aedes albopictus (the tiger mosquito), which also serve as vectors for dengue and Zika viruses. These mosquito species bite primarily during daylight hours, with activity peaks in the early morning and late afternoon. Aedes aegypti feeds both indoors and outdoors, while both species lay eggs in containers with standing water. When an uninfected mosquito feeds on a viremic person during the first week of illness, the virus is ingested and replicates in the mosquito over several days before reaching salivary glands, enabling transmission to subsequent hosts. Rare instances of mother-to-child transmission during pregnancy or at birth have been documented.

Source-backed detail on specific high-risk groups is not yet available beyond the general observation that the very young, elderly individuals, and those with pre-existing health conditions are at elevated risk for more severe disease manifestations.

Prevention of chikungunya relies fundamentally on mosquito population control and individual protection from bites in areas where transmission occurs. Vector control measures include reducing mosquito breeding sites by eliminating standing water in containers and other artificial habitats, along with community-level insecticide-based interventions. Personal protective measures include the use of Environmental Protection Agency-registered insect repellents, wearing long-sleeved clothing, and utilizing bed nets, particularly for those unable to avoid exposure during peak biting periods. No specific antiviral treatment exists; clinical management is supportive, focusing on fever reduction and pain relief, with paracetamol recommended until dengue is excluded due to bleeding risks associated with NSAIDs. Two chikungunya vaccines have received regulatory approval in certain jurisdictions, though they remain not widely available or deployed in routine immunization programs.

Chikungunya surveillance must account for substantial clinical overlap with dengue fever, Zika virus infection, and other endemic febrile illnesses, which complicates case identification and may result in underdiagnosis. Laboratory confirmation during the first week of illness is achieved through detection of viral RNA via reverse transcriptase-polymerase chain reaction (RT-PCR) or viral culture; after this period, serological testing for virus-specific antibodies becomes the primary diagnostic approach, with antibodies typically detectable by one week post-symptom onset and persisting for approximately two months. The expansion of chikungunya into previously non-endemic regions, including parts of Europe and North America through infected travelers, necessitates heightened awareness among clinicians and surveillance systems in areas where competent mosquito vectors are established. Surveillance data should be interpreted alongside dengue activity given shared vector species and overlapping geographic distribution.

1. 1 WHO Health Topics. Chikungunya.
2. 2 WHO Fact Sheet. Chikungunya fact sheet.
3. 3 WHO Q&A. Chikungunya.
4. 4 Wikidata. chikungunya.
5. 5 Wikipedia. Chikungunya - Wikipedia.

ICD-10

A92.0

ICD-11

1D46

Total cases

2K

Peak month

2025-11

Coverage

4 reporting countries · 2000-01-01 → 2026-05-09