Chikungunya

• Chikungunya fever is a viral disease transmitted to humans by the bite of infected mosquitoes.
• Chikungunya fever occurs regularly in many parts Africa and Asia.
• Symptoms include fever, headache, fatigue, nausea, vomiting, muscle pain, rash, joint pain.
• No deaths from chikungunya fever have been conclusively documented.
• There is no specific treatment, and no prevention other than avoiding mosquito bites.

What is chikungunya fever?
Chikungunya fever is a disease caused by the chikungunya virus (CHIKV), which is transmitted to humans via the bite of infected mosquitoes.

Aedes aegypti, the same mosquito that transmits yellow fever, is thought to be the primary carrier of the chikungunya virus, although other species have been found to be infected.

Where does chikungunya fever occur?
Chikungunya fever occurs regularly in many parts of Africa and Asia.

Symptoms of chikungunya fever
The illness usually involves the following symptoms: fever, headache, fatigue, nausea, vomiting, muscle pain, rash, joint pain. The time from infection (i.e. being bitten) with CHIKV until symtoms start to appear is usually about three to seven days.

Acute chikungunya fever typically lasts a few days to a couple of weeks, but some people with the disease have fatigue lasting several weeks. Also, some patients have reported joint pain lasting for weeks or even months. Immunocompromised people are at higher risk of getting seriously ill if they are infected. However, no deaths from CHIKV infection have been conclusively documented by medical science.

Medical researchers believe that once a person has had CHIKV infection (even if there are no symptoms), they gain life-long immunity to the disease.

Treatment for chikungunya fever
There is no specific treatment for chikungunya fever; treatment is aimed at relieving symptoms, and involves rest, taking in fluids, and medications such as ibuprofen or paracetamol to relieve fever and aching joints.

Can chikungunya fever be prevented?
There is no preventive drug for CHIKV infection; the best preventive measure is to avoid mosquito bites, as one would for any disease (like malaria, for example), carried by these insects:

• Wear clothing with long sleeves and cover your ankles – especially at dawn and dusk, when mosquitoes are most active. It’s also preferable to stay indoors at these times.
• Use long-lasting insecticide sprays inside homes and buildings.
• Place wire or gauze screens on all doors and windows.
• Keep a fan on in the room during the night – the current seems to put off the mosquitoes.
• Apply mosquito repellents directly to the skin.
• Use mosquito netting over the beds – these can be soaked in certain types of insecticide.
• Try to spend evenings indoors rather than outdoors, as you are much less likely to get bitten by mosquitoes.
• Blankets treated with mosquito repellents are useful.

The above measures are also important for people with chikungunya fever, who should also avoid mosquito bites so as to reduce further spread of CHIKV.

- Adapated by Olivia Rose-Innes for Health24, July 2011, from Chikungunya, Yellow Book 2012, Centers for Disease Control