The name chikungunya derives from a word in the Kimakonde language, meaning “to become contorted” and describes the stooped appearance of sufferers with joint pain. Chikungunya is a viral disease that is spread by mosquitoes. It causes fever and severe joint pain. Other symptoms include muscle pain, headache, nausea, fatigue and rash.
The disease is transmitted by the same mosquitoes involved in the dengue transmision (Aedes aegypti and Aedes albopictus). It also shares some clinical signs with dengue and can be misdiagnosed in areas where dengue is common.
There is no cure for the disease. Treatment is focused on relieving the symptoms.
The proximity of mosquito breeding sites to human habitation is a significant risk factor for chikungunya.
Since 2004, chikungunya fever has reached epidemic proportions, with considerable morbidity and suffering.
The disease occurs in Africa, Asia and the Indian subcontinent. In recent decades, mosquito vectors of chikungunya have spread to Europe and the Americas. In 2007, disease transmission was reported for the first time in a localized outbreak in north-eastern Italy.
After the bite of an infected mosquito, onset of illness occurs usually between four and eight days but can range from two to 12 days.
For protection during outbreaks of chikungunya, clothing which minimizes skin exposure to the Aedes aegypti mosquito, which tends to bite during the day, is advised, as is the use of repellents which can be applied to exposed skin or to clothing. Repellents should contain DEET. For those who sleep during the daytime, particularly young children, or sick or older people, insecticide treated mosquito nets afford good protection. Mosquito coils or other insecticide vaporizers may also reduce indoor biting.
Basic precautions should be taken by people traveling to risk areas and these include use of repellents, wearing long sleeves and pants and ensuring rooms are fitted with screens to prevent mosquitoes from entering.
Signs and symptoms
Chikungunya is characterized by an abrupt onset of fever frequently accompanied by joint pain. Other common symptoms are muscle pain, headache, nausea, fatigue and rash. The joint pain is often very debilitating and can last for weeks.
Most patients recover fully, but in some cases joint pain may persist for several months, or even years. Occasional cases of eye, neurological and heart complications have been reported, as well as gastrointestinal complaints.
Serious complications are not common, but in older people, the disease can contribute to the cause of death. Often symptoms in infected individuals are mild and the infection may go unrecognized, or be misdiagnosed in areas where dengue occurs.
There is no specific antiviral drug treatment for chikungunya. Treatment is directed primarily at relieving the symptoms, including the joint pain using anti-pyretics, optimal analgesics and fluids. There is no commercial chikungunya vaccine.
Caribbean countries reporting chikungunya include: Anguilla, Antigua and Barbuda, Aruba, Barbados, British Virgin Islands, Cuba, Dominica, Dominica Republic, French Guyana, Grenada, Guadeloupe, Guyana, Haiti, Martinique, Puerto Rico, St. Barthelemy, St. Kitts and Nevis, St. Lucia, Sint Maarten, St. Martin, St. Vincent and the Grenadines, Suriname, Turks and Caicos Islands, U.S. Virgin Islands and Venezuela.
Sources: World Health Organization, Centers for Disease Control and Prevention