What is Chikungunya?

Chikungunya fever is a viral disease transmitted to humans by the bite of infected mosquitoes. It is a preventable and self limiting disease.

The classical symptoms are fever, rash and joint pain.

What is the current status of the disease?

The virus is called Alphavirus (Species – Chikungunya).

It was first isolated from the blood of a febrile patient in Tanzania in 1953, and has since been identified repeatedly in west, central and southern Africa and many areas of Asia, and has been cited as the cause of numerous human epidemics in those areas since that time.

CHIKV is spread by the bite of an infected mosquito. Mosquitoes become infected when they feed on a person infected with CHIKV. Infected mosquitoes can then spread the virus to other humans when they bite.
Aedes aegypti, a household container breeder and aggressive daytime biter which is attracted to humans, is the primary vector of CHIKV to humans.

Outbreaks typically involve several hundreds or thousands of cases but deaths are rarely encountered.

Present epidemic
Since the beginning of the epidemic in March 2005, 2, 66 000 cases of chikungunya fever are estimated to have occurred on the island of Reunion, a French overseas territory. The islands of the southwest Indian Ocean (including Comoros, Madagascar, Mauritius, Mayotte, and Seychelles), and several states of India have been affected by chikungunya epidemics in 2005-2006.

Chikungunya virus is no stranger to the Indian sub-continent. Since its first isolation in Calcutta, in 1963, there have been several reports of chikungunya virus infection in different parts of India. The last outbreak of chikungunya virus infection occurred in India in 1971. Recent reports of large scale outbreaks of fever caused by chikungunya virus infection in several parts of Southern India have estimated that over 1,80,000 cases have occurred in India since December 2005.

Chikungunya infection in pregnancy: Virus can spread to the baby in the uterus from an infected mother. What are the symptoms of the disease?

The disease starts 2-3 days (range 1-12days) after bite of an infected mosquito who injects the virus to the blood of man. The symptoms are Fever which lasts for 2 – 3 days usually. The temperature can be very high with occasional chills. There would be pain in the joints, usually affecting hands, wrists, ankles and feet, with lesser involvement of larger joints. Muscle ache may also occur. Mild joint symptoms will last only a few weeks. More severe cases takes months to get well. Patients can also have rashes on the skin. Headache and redness of eyes also can occur. The disease could be rarely dangerous in those who are ill otherwise or have low resistance power (very old/ newborn).

Outbreaks typically result in several hundreds or thousands of cases but deaths are rarely encountered.

 

Some blood tests are available for confirming diagnosis. However these need not be done for treatment purpose and is required only for research and planning purposes.

Treatment

The disease is usually selflimiting & will resolve with time. Rest and proper nutrition is important. Drugs are given for fever, pain and fluids if there is dehydration. Patients should be protected from further mosquito exposure (staying indoors and/or under a mosquito net during the first few days of illness) so that they don’t cause further spread of disease.

Prevention.

 The best way to avoid CHIKV infection is to prevent mosquito bites. There is no vaccine or preventive drug.