Chikungunya Fever

Chikungunya fever is a debilitating, but non-fatal, viral illness. It is spread by the bite of infected female Aedes aegypti mosquito. Aedes mosquito breeds in clean water collections. The water containers, tanks, discarded material such as buckets, utensils, tyres, flower-pots etc. are the breeding sites for these mosquitoes. The peak biting times of the Aedes aegypti mosquito are early morning or late evening. Chikungunya fever is caused by a virus of genus alphavirus in the family of togaviridae.  It is diagnosed based on symptoms, physical findings (e.g. joint swelling), laboratory testing and the possibility of exposure to infected mosquitoes. There is no specific treatment for Chikungunya fever. The treatment is mainly supportive to ease the symptoms.

•  Chikungunya Fever

References:
www.who.int
www.nvbdcp.gov.in
www.cdc.gov
www.icmr.nic.in

The content of this module has been validated by Dr. Indu Grewal, Central health Education Bureau New Delhi , on 3rd November 2014.

It is generally characterized by abrupt onset of fever, chills which is accompanied by joint pain. Other symptoms include:

• Muscle pain
• Fatigue and Nausea
• Headache
• Rash
• The joint pain is often very debilitating, but usually ends within a few days or weeks.

References:
www.cdc.gov

Chikungunya virus is spread by the bite of an infected mosquito. Mosquitoes become infected when they feed on a person infected with Chikungunya virus. The incubation period (time from infection to illness) can be 2-12 days, but is usually 3-7 days. “Silent” Chikungunya virus infections (infections without illness) do occur, though rarely.

References:

www.nvbdcp.gov.in
www.cdc.gov

The clinical appearance of both chikungunya and dengue are similar. Therefore laboratory confirmation is important especially in areas where dengue is present. Enzyme-Linked Immuno-sorbent Assay (ELISA) may confirm the presence of IgM and IgG anti-Chikungunya antibodies.

Various reverse transcriptase–polymerase chain reaction (RT–PCR) methods are also available but are of variable sensitivity. RT–PCR products from clinical samples may also be used for genotyping of the virus, allowing comparisons with virus samples from various geographical sources.

References:
www.who.int
www.icmr.nic.in

There is no specific treatment for chikungunya. Only supportive treatment is given to ease the symptoms

• Administration of non-steroidal anti-inflammatory drugs help in relieving pain.
• Antiviral drugs like acyclovir are also given (but given only in complicated cases as prescribed by doctor).
• Fluid intake: Plenty of fluids intake helps in keeping hydrated.
• Infected persons should be isolated from mosquitoes as much as possible in order to avoid transmission of infection to other people.

References:
www.who.int

There is neither chikungunya virus vaccine nor drugs are available to cure the infection. Prevention from mosquito bites is the key. Eliminating mosquito breeding sites is another key prevention measure.
Prevention is similar to those for other viral diseases transmitted by mosquitoes, such as dengue:

• Use insect repellent containing DEET, Picaridin, oil of lemon eucalyptus on exposed skin. Always follow the directions on the package.
• Wear long sleeves and pants (ideally treat clothes with permethrin or another repellent).
• Have secure screens on windows and doors to keep mosquitoes out.
• Additionally, a person with chikungunya fever should limit his exposure to mosquito bites to avoid further spreading the infection. The person should use repellents when outdoors exposed to mosquito bites or stay indoors in areas with screens or under a mosquito net.

References:
www.cdc.gov