This site is currently implementing core features and is not ready for patient use yet.
This site is currently implementing core features and is not ready for patient use yet.
For informational purposes only — not medical advice
Get a free vaccination guide and nearby clinic recommendations — straight to your inbox.
How serious?
Risk of death
Yes
Vaccine available?
Time to symptoms
Countries affected
Active outbreaks
Transmitted by daytime-biting Aedes mosquitoes (same as dengue). Prevention relies on mosquito bite avoidance. If you develop fever with severe joint pain during or after tropical travel, seek medical evaluation. Chronic arthralgia is the main long-term concern.
Viral disease transmitted by Aedes mosquitoes causing high fever and severe, often debilitating joint pain. A vaccine (Ixchiq) was approved by FDA in November 2023.
Symptoms | Frequency | Severity | Onset |
|---|---|---|---|
| Arthralgia | 95% | Severe | Early |
| Headache | 65% | Mild | Early |
| High fever | 95% | Severe | Early |
| Malaise | 75% | Mild | Early |
| Myalgia | 70% | Moderate | Early |
| Back pain | 50% | Moderate | Early |
| Chills | 40% | Mild | Early |
| Photophobia | 10% | Mild | Early |
| Retro-orbital pain | 18% | Mild | Early |
| Joint swelling | 45% | Moderate | Peak |
| Maculopapular rash | 50% | Mild | Peak |
| Edema | 30% | Mild | Peak |
| Itching | 25% | Mild | Peak |
| Loss of appetite | 35% | Mild | Peak |
| Nausea | 40% | Mild | Peak |
| Conjunctivitis | 20% | Mild | Peak |
| Diarrhea | 15% | Mild | Peak |
| Dizziness | 10% | Mild | Peak |
| Swollen lymph nodes | 15% | Mild | Peak |
| Vomiting | 25% | Mild | Peak |
| Petechiae | 5% | Mild | Peak |
| Fatigue | 80% | Moderate | Any phase |
Chikungunya is an acute viral illness caused by the chikungunya virus (CHIKV), an alphavirus of the family Togaviridae, transmitted to humans through the bite of infected Aedes aegypti and Aedes albopictus mosquitoes. The name derives from the Makonde language (spoken in parts of Tanzania and Mozambique) and means "that which bends up" or "to become contorted," describing the stooped posture adopted by patients suffering from the disease's hallmark symptom: severe, debilitating polyarthralgia.
First isolated during an outbreak in Tanzania in 1952, chikungunya circulated for decades in Africa and Southeast Asia, causing periodic epidemics. The virus re-emerged dramatically in 2004–2005 with a massive outbreak originating on the coast of Kenya and spreading across the Indian Ocean islands (Réunion, Mauritius, Mayotte, Seychelles) and into India, where an estimated 1.4 million cases occurred. A key adaptive mutation (A226V in the E1 envelope glycoprotein) enhanced viral replication in Aedes albopictus, expanding the vector range into temperate regions.
In 2013, autochthonous transmission was first documented in the Americas (Saint Martin), followed by explosive spread through the Caribbean and Central and South America, with over 2.5 million suspected cases by 2016. Local transmission has also been documented in southern Europe (Italy 2007 and 2017, France 2010 and 2014), reflecting the established presence of Ae. albopictus in the Mediterranean basin. Chikungunya is unique among arboviruses for its exceptionally high attack rate (72–97% of infected individuals become symptomatic) and the prolonged, disabling nature of its joint disease.
Causative agent: Chikungunya virus (CHIKV), an enveloped, single-stranded positive-sense RNA virus of the genus Alphavirus, family Togaviridae. Three major genotypes: West African, East-Central-South African (ECSA), and Asian. The ECSA genotype with the Indian Ocean lineage (carrying the A226V mutation) has driven recent global expansion.
Transmission: Primarily through bites of Aedes aegypti (tropical) and Ae. albopictus (temperate to subtropical) mosquitoes. Urban transmission cycle: human → mosquito → human (no animal reservoir required for epidemics). Rare: vertical transmission (intrapartum, up to 49% risk when mother is viremic at delivery), blood transfusion, and laboratory exposure.
Incubation period: 2–12 days, most commonly 3–7 days.
Attack rate: Unusually high for an arbovirus: 72–97% of CHIKV-infected individuals develop symptomatic disease (compare: dengue ~25%, Zika ~20%).
Epidemiological status: Endemic in sub-Saharan Africa, South and Southeast Asia, Indian Ocean islands, and the Americas. Continues to cause large outbreaks, with >3 million cases reported globally since 2004. The WHO classified chikungunya as a priority pathogen for vaccine development.
Vaccine: Ixchiq (VLA1553), a live-attenuated vaccine manufactured by Valneva, was approved by the FDA in November 2023 for adults ≥18 years at increased risk of CHIKV exposure — the first chikungunya vaccine ever licensed.
Seek immediate medical attention if any of the following develop:
Atypical severe manifestations:
Altered consciousness, confusion, or seizures — may indicate chikungunya encephalitis (rare but serious, especially in neonates and elderly)
Persistent vomiting with inability to maintain oral hydration
Severe abdominal pain (hepatitis, rare)
Mucosal bleeding: gingival bleeding, epistaxis, petechiae — while more typical of dengue, atypical hemorrhagic manifestations of chikungunya have been reported during large outbreaks
Dark or reduced urine output (possible acute kidney injury)
High-risk populations requiring urgent evaluation:
Neonates born to viremic mothers: Intrapartum transmission causes neonatal chikungunya, which can present with encephalopathy, seizures, disseminated intravascular coagulation (DIC), and myocarditis. Mortality in severe neonatal disease is 3–5%. Any neonate with fever and irritability born to a mother with febrile illness around delivery should be urgently evaluated.
Elderly patients (>65 years): Higher risk of encephalitis, decompensation of cardiac or respiratory comorbidities, and death. CFR in elderly during outbreaks is 3–5%, compared to <0.1% in the general population.
Immunocompromised patients: May develop atypical and more severe presentations.
Differentiation from dengue (co-endemic areas):
In areas where dengue and chikungunya co-circulate, any febrile patient with warning signs of severe dengue (abdominal pain, vomiting, mucosal bleeding, hepatomegaly, rising hematocrit with falling platelets) should be managed as potential dengue until proven otherwise.
Avoid aspirin and NSAIDs until dengue has been excluded.
Most common signs and symptoms
Acute phase (days 1–14):
Fever: Abrupt onset of high fever (often ≥39°C, sometimes ≥40°C), typically lasting 2–5 days. Fever may be biphasic ("saddleback" pattern) with a brief afebrile period before recurrence.
Polyarthralgia — the defining symptom: Severe, bilateral, symmetric joint pain, typically affecting multiple joints simultaneously. The small joints of the hands, wrists, ankles, and feet are most commonly involved, but large joints (knees, shoulders, elbows, hips) and the axial skeleton (cervical spine, lumbar spine, sacroiliac joints) may also be affected. The pain is often described as the worst joint pain patients have ever experienced, frequently incapacitating — patients are unable to walk, grip objects, or perform basic activities of daily living.
Other acute symptoms:
Maculopapular rash: appears 2–5 days after fever onset in 40–75% of cases. Distributed on trunk and extremities. May be pruritic.
Headache, myalgia, and fatigue
Periarticular edema (swelling around joints, especially ankles, wrists, and fingers)
Conjunctival injection (less prominent than in Zika)
Lymphadenopathy (10–15%)
Gastrointestinal symptoms: nausea, vomiting, diarrhea (uncommon)
Post-acute phase (weeks 3–12):
Persistent or recurrent arthralgia, typically milder than the acute phase but still functionally limiting.
Fatigue, depression, and reduced quality of life.
Chronic phase (>3 months):
Chronic inflammatory rheumatism: 30–60% of patients experience persistent joint symptoms at 1 year, 12–18% at 3 years. Symptoms resemble rheumatoid arthritis: morning stiffness, joint swelling, and pain.
Risk factors for chronicity: age >45, pre-existing joint disease, severe acute phase, female sex.
Knowing the symptoms is the first step to a quick response.
Typical disease course:
Key feature: The severity of arthralgia distinguishes chikungunya from dengue and Zika. Joint pain can be so severe that patients cannot walk or perform daily activities.
How this disease is identified
Molecular diagnosis (acute phase, first 7 days):
RT-PCR: Detection of CHIKV RNA in serum. Highly sensitive during the first 5 days of illness when viremia is high (titers up to 10⁸–10⁹ copies/mL). Sensitivity declines rapidly after day 5. RT-PCR also provides genotype identification for epidemiological purposes.
Viremia duration: typically 5–7 days, occasionally up to 12 days. Coincides with the febrile phase.
Serological diagnosis (from day 5 onward):
IgM ELISA: CHIKV-specific IgM antibodies appear by day 5 of illness, peak at 2–3 weeks, and may persist for 3–6 months (sometimes longer). Positive IgM supports a recent infection.
IgG ELISA: IgG appears 1–2 weeks after symptom onset and persists for years, providing long-term immunity. A ≥4-fold rise in IgG titer in paired sera (acute and convalescent, 2–4 weeks apart) confirms recent infection.
Cross-reactivity: Unlike flaviviruses, alphaviruses show limited serological cross-reactivity. However, cross-reactions with o'nyong-nyong virus (closely related alphavirus, co-circulating in Africa) can occur. Neutralization assays (PRNT) can differentiate if needed.
Rapid diagnostic tests:
Supportive laboratory findings:
Differential diagnosis: Dengue (co-circulation common; dengue has more hemorrhagic features), Zika (milder, prominent conjunctivitis), o'nyong-nyong (Africa only), post-infectious reactive arthritis, rheumatoid arthritis onset, Ross River virus (Australia/Pacific).
Available treatment methods
There is no specific antiviral treatment for chikungunya. Management is supportive, with a focus on pain control and prevention of chronic arthropathy.
Acute phase treatment:
Rest: Essential during the febrile phase. Physical rest reduces viral replication in musculoskeletal tissues and may reduce the risk of chronic arthralgia.
Hydration: Adequate oral fluid intake. Intravenous fluids if oral intake is compromised.
Analgesia: Paracetamol (acetaminophen) is first-line for pain and fever.
NSAIDs: After dengue has been excluded (typically after day 5–7 or with confirmed chikungunya diagnosis), NSAIDs (ibuprofen, naproxen, diclofenac) are effective for joint pain and inflammation. Avoid aspirin (risk of hemorrhagic complications and Reye syndrome in children).
Avoid corticosteroids in the acute phase: No proven benefit and potential to prolong viremia.
Post-acute and chronic arthralgia management:
NSAIDs remain first-line for persistent inflammatory joint symptoms.
Short courses of low-dose corticosteroids (prednisolone 5–10 mg/day) may be considered for patients with severe, refractory polyarthritis not responding to NSAIDs, under rheumatological supervision.
Disease-modifying antirheumatic drugs (DMARDs): Methotrexate or hydroxychloroquine have been used in chronic chikungunya arthritis resembling rheumatoid arthritis, based on observational studies and extrapolation from RA treatment guidelines.
Physiotherapy: Early mobilization and range-of-motion exercises help prevent joint stiffness and contractures.
Special populations:
Neonates: Supportive care in NICU for severe neonatal chikungunya (seizures, encephalopathy, DIC).
Elderly: Close monitoring for decompensation; lower threshold for hospitalization.
Pregnancy: Paracetamol only for analgesia. NSAIDs are contraindicated, especially in the third trimester.
Most cases are effectively treated with early diagnosis.
How to protect yourself
Vaccination:
Ixchiq (VLA1553): The first chikungunya vaccine, approved by the US FDA in November 2023 (Valneva). A live-attenuated, single-dose vaccine for adults ≥18 years at increased risk of CHIKV exposure. Phase 3 trials demonstrated 98.9% seroconversion at day 28, with neutralizing antibodies persisting through at least 12 months.
Contraindications: immunocompromised individuals, pregnancy, lactation (live vaccine).
Additional vaccine candidates are in development, including virus-like particle (VLP) vaccines and mRNA platforms.
The availability of a licensed vaccine represents a major breakthrough, though deployment is currently limited to travelers and residents of endemic areas in countries where it is registered.
Mosquito bite prevention — the primary preventive strategy for most populations:
Aedes aegypti and Ae. albopictus are daytime biters (peak activity: early morning and late afternoon). Standard nighttime-only measures (bed nets) are insufficient.
Use insect repellents containing DEET (20–50%), picaridin (20%), or IR3535 on exposed skin during daytime hours.
Wear protective clothing: long sleeves, long trousers, socks. Light-colored clothing makes ticks and mosquitoes easier to spot.
Permethrin-treated clothing provides additional protection (effective through multiple washes).
Use air conditioning or window/door screens in accommodations.
Environmental vector control:
Eliminate or treat standing water around homes and communities. Aedes mosquitoes breed in small artificial containers: flower pot saucers, discarded tires, water storage drums, roof gutters, and even bottle caps.
Community-level source reduction programs are the most effective long-term strategy but require sustained engagement.
Larvicides (Bti, temephos) and adulticides (pyrethroids) for outbreak response.
Novel approaches: Wolbachia-infected mosquito releases, sterile insect technique, and genetically modified mosquitoes are under investigation.
Preparation is the best protection.
Pre-travel preparation:
Check CDC and WHO traveler health resources for current chikungunya activity at your destination. Risk areas include sub-Saharan Africa, South and Southeast Asia, the Indian Ocean islands, the Caribbean, and Central and South America.
Consider Ixchiq vaccination (if available and indicated) for travel to endemic or epidemic areas, particularly for extended stays. Single dose provides rapid protection (seroconversion within 28 days).
Pack insect repellent (DEET or picaridin-based), permethrin-treated clothing, and a portable mosquito net if accommodations may not be screened.
During travel:
Apply insect repellent consistently during daytime hours, reapplying as directed.
Be especially vigilant during early morning and late afternoon hours when Aedes mosquitoes are most active.
Choose accommodations with screened windows and air conditioning when possible.
In areas with active outbreaks, consider limiting time outdoors during peak mosquito hours.
If you develop high fever with severe joint pain during your trip, seek local medical attention. Inform the clinician of your location and potential chikungunya exposure. Rest completely — physical exertion during acute illness may worsen outcomes.
Post-travel:
Symptom onset can occur up to 12 days after the last mosquito exposure. If you develop fever with joint pain within 2 weeks of returning from an endemic area, consult a healthcare provider and mention your travel history.
Prevent onward transmission: If diagnosed with chikungunya, protect yourself from mosquito bites for the first 7 days of illness (the viremic period). If Aedes mosquitoes are present in your home area, an infected person bitten by a local mosquito could theoretically initiate local transmission.
Chronic arthralgia may persist for months. Seek rheumatological evaluation if joint symptoms continue beyond 3 months.
Statistics and geographic data
Historical epidemiology:
1952: First isolation of CHIKV during an outbreak on the Makonde Plateau, Tanzania. The virus caused periodic epidemics in Africa and Southeast Asia for the following 50 years.
2004–2006: Re-emergence. A massive outbreak began in coastal Kenya and spread to the Indian Ocean islands (Réunion: ~266,000 cases in a population of 770,000; attack rate 34%). India: 1.4 million cases in 2006.
The Réunion outbreak was notable for the emergence of the A226V mutation in the E1 envelope protein, which enhanced viral fitness in Ae. albopictus, expanding the geographic range of the virus into temperate regions.
Americas invasion (2013–present):
December 2013: First autochthonous cases in the Americas on Saint Martin (French overseas territory).
By 2015: >1.7 million suspected cases across 45 countries and territories in the Americas.
2014–2016: >2.5 million suspected cases in the Americas, with major epidemics in the Caribbean, Colombia, Brazil, and Central America.
European outbreaks:
Italy (Emilia-Romagna) 2007: 217 cases — the first autochthonous chikungunya outbreak in Europe, mediated by Ae. albopictus.
Italy (Lazio and Calabria) 2017: >500 cases.
France: small autochthonous clusters in 2010, 2014, 2017, 2023.
These outbreaks demonstrate the vulnerability of southern Europe to chikungunya, given established Ae. albopictus populations throughout the Mediterranean.
Global burden:
Since 2004, an estimated 10+ million chikungunya cases have occurred globally. The WHO estimates that CHIKV circulates in >110 countries.
The disease burden is substantially underestimated: many cases are misdiagnosed as dengue, diagnostic capacity is limited in endemic settings, and mild cases may not seek care.
Economic impact is significant due to prolonged disability: the chronic arthralgia phase causes substantial loss of work productivity and reduced quality of life, lasting months to years.
Who is most at risk
Risk factors for infection:
Geographic exposure: Travel to or residence in areas with active CHIKV transmission. The virus circulates in more than 110 countries across Africa, Asia, the Americas, and the Indian Ocean region.
Mosquito exposure: Daytime outdoor activities in tropical and subtropical settings, lack of air-conditioned or screened accommodation, proximity to Aedes breeding sites (urban and peri-urban areas).
Epidemic settings: During outbreaks, attack rates can reach 30–75% of the population within months due to the high viremic titers in infected humans and efficient Aedes-mediated transmission.
Non-immune status: Unlike dengue (where prior heterotypic infection increases severe disease risk), prior chikungunya infection confers robust, likely lifelong immunity. Risk is concentrated in immunologically naive populations.
Risk factors for severe acute disease:
Age extremes: Neonates (especially those exposed to maternal viremia during delivery) and elderly patients (>65 years) have the highest risk of severe and fatal disease.
Comorbidities: Cardiovascular disease, diabetes, chronic respiratory disease, and chronic kidney disease increase the risk of decompensation and death during acute infection.
Immunosuppression: Higher risk of atypical and severe presentations, though data are limited.
Risk factors for chronic arthralgia (the most common long-term consequence):
Age >45 years: The strongest and most consistently identified risk factor for chronic chikungunya arthralgia.
Female sex: Women are more likely to develop chronic joint symptoms, possibly related to hormonal influences on immune responses.
Pre-existing joint disease: Osteoarthritis, rheumatoid arthritis, or prior joint injuries increase the risk of persistent symptoms.
Severity of acute illness: Higher initial joint pain scores, greater number of affected joints, and longer duration of acute symptoms predict chronicity.
Comorbid conditions: Diabetes and hypertension have been associated with increased risk of chronic arthralgia in some cohort studies.
Potential complications
Chronic inflammatory rheumatism — the signature complication:
The most important and debilitating complication of chikungunya, affecting 30–60% of patients at 3 months, 12–18% at 3 years, and up to 5–10% at 5 years after acute infection.
Persistent or relapsing polyarthralgia and polyarthritis, typically affecting the same joints as the acute illness (small joints of hands and feet, wrists, ankles).
Clinical presentation mimics rheumatoid arthritis: morning stiffness >30 minutes, symmetric joint swelling, elevated inflammatory markers (CRP, ESR).
Mechanism: persistence of CHIKV RNA and antigens in synovial tissue and macrophages triggers ongoing inflammatory responses. Viral persistence has been demonstrated in joint tissue biopsy specimens months to years after acute infection.
Structural joint damage (erosions) has been documented on imaging in a subset of patients with chronic disease, resembling inflammatory erosive arthritis.
Acute atypical and severe manifestations (rare, <1% of cases, but potentially life-threatening):
Encephalitis: Most commonly affects neonates (neonatal chikungunya encephalopathy, with long-term neurodevelopmental sequelae in 50% of affected infants) and elderly patients. Adult encephalitis is rare but carries significant morbidity.
Myocarditis: Inflammation of cardiac muscle, predominantly in patients with pre-existing cardiovascular disease.
Hepatitis: Elevated transaminases, occasionally acute liver failure (extremely rare).
Acute kidney injury: Usually in the context of dehydration, rhabdomyolysis, or pre-existing renal disease.
Bullous dermatosis: Large blistering skin lesions, more common in infants and young children.
Ocular complications: Anterior uveitis, retinitis, optic neuritis (rare, usually self-limiting).
Guillain-Barré syndrome: Reported in association with chikungunya, though less frequently than with Zika virus.
Mortality:
Overall CFR: <0.1% during epidemics.
Mortality is concentrated in neonates (CFR 3–5% for symptomatic neonatal disease) and elderly patients with comorbidities (CFR 3–5% in patients >65 years during outbreaks).
Excess mortality during large outbreaks may be underestimated, as deaths from decompensated comorbidities in elderly patients may not be attributed to chikungunya.
Expected outcomes and recovery
Acute phase: Self-limiting. CFR <0.1% (higher in neonates and elderly >65 years).
Chronic arthralgia: The defining long-term consequence.
40–60% of patients experience persistent or relapsing joint pain lasting months to years.
12–15% still have disabling arthralgia at 3 years post-infection.
Risk factors for chronicity: older age, female sex, pre-existing joint disease, severe acute arthralgia.
Rare severe complications: Encephalitis (neonates, elderly), myocarditis, hepatitis, renal failure.
Neonatal chikungunya: Intrapartum mother-to-child transmission. CFR up to 10%, with severe encephalopathy.
This disease is vaccine-preventable. Effective protection is available through vaccination.
Talk to a travel health specialist about the recommended schedule before your trip.
Find a vaccination clinic →The content on this page is for informational and educational purposes only. It does not constitute medical advice, diagnosis, or treatment recommendations. If you have health concerns, consult a qualified healthcare professional. Medova is not a medical service provider.
Full terms of useGeographic distribution and active outbreaks
| Flag | Country | Risk level |
|---|---|---|
 | Indonesia | High risk |
 | Philippines | High risk |
 | Bangladesh | High risk |
 | Thailand | High risk |
 | Brazil | High risk |
 | India | High risk |
 | Pakistan | High risk |
 | Costa Rica | High risk |
 | Suriname | High risk |
 | Mozambique | High risk |
Know which vaccine you need? Great. Not sure? Just tell us your destination — we will figure it out and match you with a clinic. Free, no obligation.
A comprehensive overview of tropical diseases by travel region: dengue, malaria, yellow fever, Zika, typhoid, and chikungunya — risk levels, seasons, prevention, and vaccine availability.
A practical guide for returning travelers: symptoms to watch, incubation periods for tropical diseases, a post-travel checklist, and red flags that need immediate medical attention.
