Chikungunya is a debilitating illness caused by a virus transmitted through mosquito bites. Chikungunya was first described during an outbreak in southern Tanzania in the year 1952.
The name “chikungunya” comes from the Kimakonde language(language spoken by the Makonde, an ethnic group in southeast Tanzania and northern Mozambique.), and means “to become contorted”. This word describes the stooped appearance of patients because of severe joint pain or arthralgia.
What is Chikungunya fever?
Chikungunya fever is a self limiting disease characterised by high grade fever and disabling joint pains. Chikungunya fever symptoms are quite similar to those of Dengue. Chikungunya fever is common in Asia, Africa, South america, and certain parts of Europe, with repeated outbreaks seen from time to time. The disease is non-fatal. There are no vaccines available and mosquito breeding control is the only prevention possible.
How is Chikungunya transmitted?
Chikungunya is a mosquito transmitted viral illness. The mosquito that transmits the disease is female Aedes Aegypti and Aedes albopictus, and direct human to human transmission is not possible. It is to be noted that both these mosquitoes also spread Dengue.
So both dengue and chikungunya viruses are transmitted by these urban-dwelling mosquito that bites primarily at dawn and dusk. Both the species of mosquitoes bite outdoors, but Aedes aegypti also bites indoors.
What are the symptoms of Chikungunya?
The onset of symptoms usually occurs between 4 and 8 days(range from 2 to 12 days).
Symptoms of Chikungunya typically start with an abrupt onset of high grade fever with chills and is frequently associated with severe joint pain. Other accompanying features include muscle pain or myalgia, headache, nausea, fatigue and rash.
Joint pain may be associated with joint swelling and is the most debilitating symptom of the disease. It involves predominantly small joints like that of hands, wrists and ankles. The joint pains are so severe, that patient has difficulty in carrying out daily chores.
The rash associated with Chikungunya involves predominantly upper limbs and face, but can also occur on trunk and lower limbs.
The symptoms last for a week but in some cases joint pains may last for a month, hence becoming chronic.
The symptoms of Chikungunya are quite indistinguishable from those of Dengue.
How is Chikungunya diagnosed?
Chikungunya diagnosis is based on presence of typical clinical symptoms, with residence or travel to an endemic area. Chikungunya virus can be isolated during the initial phase of the illness using various reverse transcriptase–polymerase chain reaction (RT–PCR) methods available.
Serological tests based on detection of anti-bodies may confirm the presence of IgM and IgG anti-chikungunya antibodies. IgM antibody peak around 3 to 5 weeks after the onset of illness and persist for about 2 months, and hence are not helpful during the symptomatic phase of the disease.
What is the treatment of Chikungunya?
There is no specific antiviral drug treatment for chikungunya. It is a self limiting disease. Treatment is mainly directed at
Relieving the symptoms.
Drink plenty of fluids to prevent dehydration.
Paracetamol to reduce fever and pain.
Avoid Aspirin and other non-steroidal anti-inflammatory drugs (NSAIDS until dengue is ruled out)
What are the complications of Chikungunya fever?
Chikungunya disease is rarely fatal. Most patients recover in a few weeks.
Long term joint pain is the commonest long term complication from Chikungunya infection. Discomfort in walking, or other daily activities may persist for more than 18 months. Patients with Chikungunya have a 10% chance of getting chronic joint pains.
Some studies also suggest that patients are more prone to having other joint diseases like Rheumatoid arthritis.
What are the main differences between Chikungunya and Dengue fever?
Although most of the symptoms are same, but Chikungunya does not cause much effects on blood cells especially platelets. While in Dengue reduction in platelets is the hallmark causing bleeding complications that are responsible for mortality and morbidity, in Chikungunya platelets remain normal.
Unlike Dengue, where reinfection is possible and may be more severe and fatal than the first infection, Chikungunya infection confers life long immunity.
How to prevent Chikungunya?
Prevention and control of mosquito breeding, and biting is the only way at present to prevent Chikungunya. It is important for patients to prevent themselves also from mosquito biting as it leads to further transmission of the virus to healthy individuals.