Health talk
Chikungunya
 

Signs and Symptoms
  • Abrupt Onset of Fever
  • Joint Pain
  • Muscle Pain
  • Headache
  • Nausea
  • Fatigue
  • Rash
Definition

Chikungunya is a mosquito-borne viral disease first described during an outbreak in southern Tanzania in 1952. It is an RNA virus that belongs to the alphavirus genus of the family Togaviridae. 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 (arthralgia).

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.

How concerned should I be?

Most people recover fully, with symptoms resolving in seven to 10 days. For some people, joint pain may continue for weeks or, rarely, months. Death from chikungunya is very rare, but the virus sometimes causes severe complications, mostly in older adults. People who have been infected once are likely to be protected from future infections.

If you're traveling to an area with known outbreaks of chikungunya virus, take precautions. Because chikungunya is not transmitted from human to human, preventive measures are focused on protection from infected mosquitoes. Use insect repellent containing DEET or picaridin, wear long sleeves and pants, and stay indoors or in screened-in places when possible.

If you are an older adult or have a condition such as high blood pressure, diabetes or heart disease, you're at increased risk of severe disease. Consider avoiding travel to areas with ongoing chikungunya outbreaks.

Transmission

The virus is transmitted from human to human by the bites of infected female mosquitoes. Most commonly, the mosquitoes involved are Aedes aegypti and Aedes albopictus, two species which can also transmit other mosquito-borne viruses, including dengue. These mosquitoes can be found biting throughout daylight hours, though there may be peaks of activity in the early morning and late afternoon. Both species are found biting outdoors, but A. aegypti will also readily feed indoors.

After the bite of an infected mosquito, onset of illness occurs usually between 4 and 8 days but can range from 2 to 12 days.


Aedes aegypti

Aedes albopictus
Treatment

There is no vaccine to prevent or medicine to treat chikungunya virus. Treat the symptoms:

  • Get plenty of rest.
  • Drink fluids to prevent dehydration.
  • Take medicine such as acetaminophen (Tylenol®) or paracetamol to reduce fever and pain.
  • Do not take aspirin and other non-steroidal anti-inflammatory drugs (NSAIDS until dengue can be ruled out to reduce the risk of bleeding).
  • If you are taking medicine for another medical condition, talk to your healthcare provider before taking additional medication. If you have chikungunya, prevent mosquito bites for the first week of your illness.
  • During the first week of infection, chikungunya virus can be found in the blood and passed from an infected person to a mosquito through mosquito bites.
  • An infected mosquito can then spread the virus to other people.
Prevention and control

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. Prevention and control relies heavily on reducing the number of natural and artificial water-filled container habitats that support breeding of the mosquitoes. This requires mobilization of affected communities. During 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 immature larvae.