Biogents – Science for Your Protection –

Chikungunya virus

Chikungunya is a virus transmitted from human to human by the bite of infected mosquitoes such as Aedes aegypti and Aedes albopictus. It was first described in southern Tanzania during an outbreak in 1952, and has been identified in over 60 countries in Asia, Africa, Europe and the Americas. Since its introduction to the Caribbean in 2013, over 1.4 million suspected cases of Chikungunya have been recorded in the Caribbean islands, Latin American countries, and the United States of America. Chikungunya results in the sudden onset of fever in two to four days after exposure, and can cause joint and muscle pain, and headache. Chikungunya does not often lead to death, but the joint pain may last for months or years, and may become a cause of chronic pain and disability.

Vectors

Both Ae. aegypti and Ae. albopictus have been implicated in large outbreaks of chikungunya. Whereas Ae. aegypti is confined within the tropics and sub-tropics, Ae. albopictus also occurs in temperate and even cold temperate regions. In recent decades, Ae. albopictus has spread from Asia to become established in areas of Africa, Europe, and the Americas. There it thrives in a wider range of water-filled breeding sites than Ae. aegypti including coconut husks, cocoa pods, bamboo stumps, tree holes, rock pools, and artificial containers, such as vehicle tires, buckets, and plant saucers. This diversity of habitats allowed Ae. albopictus to exploit rural as well as peri-urban areas and shady city parks. Ae. aegypti is more closely associated with human habitation, and uses indoor breeding sites including flower vases, water storage vessels, and concrete water tanks in bathrooms, and also many of the same artificial outdoor habitats as Ae. albopictus.

The proximity of mosquito vector breeding sites to human habitation is a significant risk factor for chikungunya as well as for other diseases that these species transmit (dengue and Zika viruses). Use of mosquito repellent in strict accordance with product label instructions is a priority. The most effective repellents contain DEET, IR3535, or picaridin. For additional protection during outbreaks of chikungunya, clothing which minimizes skin exposure to the day-biting vectors is advised. Prevention and control of chikungunya virus relies heavily on reducing the number of natural and artificial water-filled container habitats that support breeding of the mosquitoes. During disease outbreaks, insecticides may be sprayed to kill flying mosquitoes, applied to surfaces in and around containers where the mosquitoes land, and used to treat water in containers to kill the larval stages.

Monitoring

Monitoring vector mosquito populations is critical to any local integrated vector management program. The goal of mosquito-based surveillance is to quantify human risk by determining the presence and abundance of local vector populations. Biogents mosquito traps such as the BG Sentinel are very effective in monitoring populations of Ae. aegypti and Ae. albopictus in a local area. For more information on controlling vectors of Zika virus see the CDC publication: Surveillance and Control of Aedes aegypti and Aedes albopictus >