Chikungunya is a viral disease transmitted to humans by the bite of an infected mosquito, primarily Aedes aegypti (yellow fever mosquito) or Aedes albopictus (Asian tiger mosquito). Most people who are infected with chikungunya virus develop symptoms. The most common symptoms are fever and joint pain, but may also include headache, muscle pain, joint swelling or rash. The illness typically lasts seven to 10 days, but some people experience incapacitating joint pain that can last for weeks or months. Except for the prolonged joint pain, chikungunya clinically presents much like dengue fever, and the two viruses are found in the same geographic areas and are transmitted by the same mosquitoes. Severe complications and fatalities are rare. There is no vaccine or specific treatment for chikungunya; treatment is generally supportive to relieve the symptoms of fever and aches.
While chikungunya is new to the Western Hemisphere, it has been around a while. The virus was first isolated from a patient in Tanzania in 1953 and has since caused large epidemics in Africa, Asia and some areas of Europe. Since 2005, several countries bordering the Indian Ocean have reported more than 1.9 million cases. In 2007, local transmission was identified for the first time in Europe during an outbreak in northeastern Italy with 197 cases; this outbreak demonstrated that transmission by Ae. albopictus mosquitoes was possible in temperate climates like Europe.
In December 2013, the first local transmission of chikungunya virus was reported in the Americas with several cases in the Caribbean island of St. Martin. Since then, local transmission of chikungunya has spread throughout Caribbean and Central and South American countries and territories, resulting in more than a million cases. The Centers for Disease Control and Prevention provides updated information on the spread of chikungunya in the Americas on their website.
So far, local transmission of chikungunya virus in the continental United States has only been identified in the state of Florida. However, there is concern that local transmission and outbreaks could occur in areas where the daytime biting mosquito vectors Ae. aegypti and Ae. albopictus occur. This is because travelers can maintain levels of virus in their blood (viremia) high enough to infect biting mosquito vectors for a week after illness onset. To prevent further spread of the virus, it is important for people to avoid mosquito bites during the first week of illness.
One of the chikungunya vectors, Ae. aegypti, is not established in Ohio. On rare occasions, it has been imported here, but cannot survive Ohio winters. The other chikungunya vector, Ae. albopictus, also known as the Asian tiger mosquito, was introduced to the United States in 1985 and has spread throughout much of the country. It has been found in 37 Ohio counties and likely occurs in others (see current map). Ae. albopictus breeds in water-holding containers, especially tires, and survives winters as eggs in Ohio. The mosquito bites during the day and feeds on a wide variety of animals including reptiles, birds and mammals.
To prevent infection with chikungunya virus, protect yourself and your family against mosquito bites:
- When outdoors, use repellents containing DEET, picaridin, IR3535, oil of lemon eucalyptus or para-menthane-diol. Follow the directions on the package.
- The mosquitoes that can transmit chikungunya virus are most active during the day. Be sure to use insect repellent and wear long sleeves and pants at these times or consider staying indoors during these hours.
- Make sure you have good screens on your windows and doors to keep mosquitoes out.
- Get rid of mosquito breeding sites by emptying standing water from flower pots, buckets and barrels. Change the water in pet dishes, and replace the water in bird baths weekly. Drill holes in tire swings so water drains out. Keep children’s wading pools empty and on their sides when they are not being used.
Animals associated with chikungunya virus include:
- Mosquitoes: Mosquitoes, primarily Aedes aegypti and Aedes albopictus, are infected with chikungunya virus when taking blood meals from infected humans. They can then transmit the virus when biting susceptible humans.
Chikungunya virus resources:
Ohio statistics and maps:
Information for travelers:
Disease reporting and surveillance:
Mosquito-borne disease prevention literature:
Last updated: 03/05/2015
Zoonotic Disease Program