Chikungunya fever is an acute viral disease caused by the chikungunya virus.

Chikungunya virus is transmitted to humans by the bite of infected mosquito. Monkeys, and possibly other wild animals, may also serve as reservoirs of the virus. Infected mosquitoes can then spread the virus to other humans when they bite.

The main vector is mosquito Aedes aegypti, the same type of mosquito that can transmit dengue fever, although other mosquitoes e.g. Aedes albopictus and Culex can also transmit the disease.

There is no direct person to person spread.

The disease was first recognized in Eastern Africa in the 1950s. The disease is endemic in many parts of the tropics. Outbreaks have occurred in recent years in Africa, Southeast Asia, South Asia (e.g. India and Sri Lanka), and the Indian Ocean islands. Closer to home, outbreaks were also reported in Malaysia and Indonesia in 2006. Imported cases of chikungunya fever have also been reported in Europe, US, South America and Asia amongst travellers returning from chikungunya fever affected areas.

The Ministry of Health (MOH) has been notified of a case of chikungunya fever in January 2008 and subsequent investigations revealed a cluster of cases likely as a result of local transmission of chikungunya fever. All previous cases of chikungunya reported in Singapore were imported i.e. the infection was contracted overseas. A total of 10 such imported cases of chikungunya fever were notified to MOH in 2007.

The disease is characterized by sudden onset of fever, chills, headache, nausea, vomiting, joint pain with or without swelling and low back pain. Some patients may develop a rash affecting the trunk and limbs. The illness is usually self-limiting. Most symptoms lasts for 3-10 days and the joint pain may last for weeks to months.

There has been no conclusively documented case in the scientific literature of the chikungunya virus affecting the nervous system or causing severe bleeding or death.

The incubation period (time from infection to illness) can be 1-12 days, but is usually 3-7 days.

There is no specific drug treatment against chikungunga virus. Treatment of chikungunya fever usually includes bed rest, fluid replacement and medication for fever and pain relief. Use of aspirin should be avoided as aspirin can increase the risk of bleeding. Hospitalization may be required for more severe cases.

Persons infected with chikungunya fever should be isolated from further mosquitoes bites (by staying indoors and/or sleeping under a mosquito net during the first few days of illness) to reduce the risk of further transmission of the virus.

At present, there is no effective vaccine for the prevention of chikungunya fever.

Chikungunya fever, like dengue fever, is a mosquito-borne disease and the best way to prevent chikungunya fever is to take precautionary measures to prevent mosquito breeding around the house and to protect against mosquito bites.  More information about the prevention of mosquito breeding can be found here.

The National Environment Agency (NEA) ensures quality environmental health, and public can report to NEA (1800-2255 632 or Contact_NEA@nea.gov.sg) about potential mosquito breeding sites. 

To reduce the risk of contracting chikungunya fever while traveling to chikungunya fever outbreak areas, travelers should take measures to reduce their exposure to mosquito bites like wearing of long-sleeved shirts and long pants when outdoors (ideally treated with permethrin or another repellent), using mosquito coils and electric vapour mats, and using insect repellent over the exposed parts of the body.