Chikungunya fever
Chikungunya is an Aedes mosquito-borne alphavirus causing abrupt high fever and severe, often symmetric, small-joint polyarthralgia that closely mimics dengue fever but is distinguished by more prominent and frequently relapsing joint disease. Diagnosis relies on serology or reverse transcriptase PCR, no antiviral or vaccine-based prevention is in routine use, and treatment is symptomatic with dengue excluded before using NSAIDs because of bleeding risk.
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What this article covers
- Overview
Chikungunya fever is a mosquito-borne alphavirus (togavirus) infection transmitted by daytime-feeding Aedes species mosquitoes, the same vector that transmits dengue and Zika viruses, and travelers…
- Epidemiology
Chikungunya virus emerged in the Americas beginning in 2013, with outbreaks in Central and South America and the Caribbean; it is endemic across many tropical and subtropical regions and should be…
- Risk factors
Travel to or residence in an endemic region (Central/South America, the Caribbean, and other tropical areas with Aedes mosquito populations) during outbreak periods.
- Pathophysiology
Chikungunya virus, an alphavirus, is inoculated into the skin by an infected Aedes mosquito bite and disseminates hematogenously, producing viremia during the acute febrile phase.
- Clinical features
Abrupt-onset high fever, up to 40°C (104°F), often with rigors and recrudescent (relapsing) fever episodes is the hallmark presenting feature.
- Differential diagnosis
Dengue fever: the most important and closely overlapping mimic; dengue features more prominent retro-orbital pain, severe lumbosacral pain, a biphasic "saddleback" fever pattern, and a greater risk…
- Diagnosis
Chikungunya is confirmed by serologic assays (IgM/IgG) or reverse transcriptase polymerase chain reaction (RT-PCR) detection of viral RNA; no formal clinical criteria set exists, and the diagnosis…
- Management
First, until dengue has been excluded, treat fever and pain with acetaminophen 650 mg PO every 6 hours as needed (not exceeding 3,000 mg/day) rather than an NSAID or aspirin, because of the bleeding…
- Complications
Chronic or relapsing polyarthralgia/arthritis persisting for months to years, the most common and functionally significant complication.
- Prognosis
The acute illness is self-limited in the large majority of patients, typically resolving in 7 to 10 days.
- Prevention
No vaccine is available, so prevention relies entirely on mosquito-avoidance measures during travel to or residence in endemic areas.
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- Zika virus infection
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