Chikungunya

How chikungunya spreads

The virus passes to people through bites from infected Aedes mosquitoes, which bite mainly during the day. These are the same mosquitoes that spread dengue and Zika. The virus does not usually spread person to person, but it can pass from mother to baby around the time of birth and, rarely, through blood.

Outbreaks occur in tropical and subtropical regions. Travelers can bring the virus home, and local transmission has occurred in southern Europe and the US where Aedes mosquitoes live.

Symptoms

Symptoms start 3 to 7 days after an infected bite:

• sudden high fever, often above 39 °C (102.2 °F)
• severe joint pain, usually in many joints on both sides of the body: hands, wrists, ankles, knees
• joint swelling and morning stiffness
• muscle pain and headache
• a red, blotchy rash on the trunk and limbs, usually 2 to 5 days after the fever begins
• fatigue, nausea and conjunctivitis

The fever lasts a few days to a week. Most people feel better within 1 to 2 weeks, but fatigue and joint pain commonly linger.

Chronic chikungunya arthritis

Many people continue to have joint pain, stiffness and swelling for months after infection, and some for years. It is more common in people over 40 and those with existing joint disease. Symptoms can resemble rheumatoid arthritis. See viral arthritis.

Severe disease

Severe illness is uncommon but more likely in newborns infected at birth, adults over 65, and people with diabetes, heart disease or high blood pressure. Complications include inflammation of the brain, heart, eyes or liver, Guillain-Barré syndrome and, rarely, death.

Chikungunya vs dengue vs Zika

Because they share mosquitoes and symptoms, doctors often test for all three.

Diagnosis

A doctor will ask about travel and symptoms. Blood tests include:

• RT-PCR to detect viral genetic material in the first week
• IgM antibody tests from about the fifth day onward
• tests for dengue and Zika, and for malaria if relevant
• blood count, liver and kidney tests

Treatment

There is no specific antiviral treatment.

• Rest and plenty of fluids.
• Acetaminophen (paracetamol) for fever and pain, following the label dose.
• Avoid aspirin and NSAIDs such as ibuprofen until dengue has been ruled out, because they increase bleeding risk in dengue.
• Once dengue is excluded, NSAIDs can help joint pain and swelling.
• Chronic arthritis may need physical therapy, NSAIDs, short courses of steroids, or disease-modifying drugs such as methotrexate, managed by a rheumatologist.
• Protect others: avoid mosquito bites during the first week of illness, when the virus is in your blood and can infect local mosquitoes.

Prevention

Mosquito bite prevention

• Use EPA-registered insect repellent (DEET, picaridin, IR3535, oil of lemon eucalyptus) on exposed skin.
• Wear long sleeves and pants, and permethrin-treated clothing.
• Stay in places with air conditioning or window screens; use bed nets.
• Empty standing water around your home.

Vaccines

A chikungunya vaccine is available in the US for some travelers aged 12 and older going to areas with outbreaks; ask a travel clinic whether it is right for you. Recommendations, especially for older adults, have been updated after reports of serious side effects, so check current CDC or local travel health advice before traveling.

Frequently asked questions

What are the symptoms of chikungunya?

The main symptoms are a sudden high fever and severe joint pain, often in the hands, wrists, ankles and knees on both sides of the body. Headache, muscle pain, joint swelling, rash and tiredness are also common. Symptoms begin 3 to 7 days after a mosquito bite.

How long does chikungunya joint pain last?

Joint pain usually improves within 1 to 2 weeks, but many people have pain and stiffness for several months, and some for a year or longer. Older adults and those with prior joint problems are more likely to have long-lasting symptoms.

Can you get chikungunya twice?

It is thought that one infection gives long-lasting immunity, so reinfection is very unlikely. However, joint symptoms from the first infection can flare repeatedly over months, which can feel like a new infection.

Is chikungunya deadly?

Deaths are rare. Most people recover fully. Severe illness is more likely in newborns, adults over 65 and people with chronic conditions such as diabetes or heart disease. The main long-term problem is persistent joint pain.