Chikungunya is a viral infection, which is transmitted to humans through the bite of an infested aedes aegypti mosquito. This virus was first identified in Tanzania in 1953. ‘Chikungunya’, in the Kimakonde language (a language spoken by people of an African tribe called Makonde) means ‘to become contorted or bent’, and this describes a chikungunya symptom in which patients tend to stoop due to joint pain. This disease has nothing to do with ‘chicken’; the misconception is mainly due to the close resemblance of the word ‘chikun’ and ‘chicken’.
The incubation period of the chikungunya virus is 2 to 5 days. Symptoms of the illness start to show once this incubation period is complete but some persons may not show signs of the illness for up to 12 days. The common symptoms are:
- High fever
- Swelling of joints and pain
- Muscle pain
- Nausea and vomiting
Symptoms of chikungunya are often confused with those of dengue or flu. In some cases there may also be extreme pain in the joints, difficulty in movement, and arthritis. Cases of eye, neurological and heart complications as well as gastrointestinal problems have also been reported.
The chikungunya virus requires an agent for transmission, and the aedes aegypti mosquito works as the transmitting agent in this case. Spread of this virus from one human to another is thus not possible. Transmission of the virus occurs when a mosquito bites an infected person and then bites a non-infected person. These mosquitoes breed in stagnant waters and bite during the day time.
There is no commercial vaccine for chikungunya. As the disease spreads through bite of aedes aegypti mosquitoes, which breed in stagnant water, the proximity of human habitation to such sites doubles the risk. It is thus important to keep our surroundings clean and not let water accumulate in containers, birdbaths, coolers, pools, potted plants etc., especially during the monsoon season. Using a mosquito repellent can significantly reduce the chances of mosquito bites. One must wear full sleeved clothes during outbreaks of chikungunya, as this minimizes skin exposure and thus mosquito bites. If required it is also advisable to use permithrin (insecticide) on clothes, shoes, and mosquito nets.
Diagnosis and Treatment
Many symptoms of chikungunya are same as those of dengue, and hence there is a risk of the disease being misdiagnosed. Chikungunya can be diagnosed through laboratory tests like Rt-PCR, serological tests and virus isolation. Recovery from the fever depends on the age and immunity of the patient. While children usually recover in 5 to 15 days, adults may recover in 1 to 2.5 months. Elderly patients may take even longer than that. There is no specific medication for chikungunya, but the treatment is directed at relieving the symptoms like fever and joint pain. Rest is advised in case of high fever and severe joint pain. Mild exercises like stretching may improve stiffness and joint pain, which generally occurs in the morning.