Chikungunya

What is Chikungunya?

Chikungunya fever is a viral disease transmitted to humans by mosquitoes, especially tiger mosquitoes. The virus was first described in East Africa in 1955. Chikungunya is a word from the Tanzanian language that means "that which bends up" or "that which contorts" referring to the symptoms caused from severe joint and muscle pains that usually accompany the infection.

What type of illnesses does the Chikungunya virus cause?

Other than severe joint and muscle pains, symptoms include fever, headache, fatigue, nausea, vomiting and skin rash.

The symptoms normally begin 3 to 7 days after being bitten by an infected mosquito, but they could begin as late as 12 days afterwards. Infections without the accompanying illness do occur, but it is not yet known how frequently this happens.

The illness typically lasts between a few days and a couple of weeks, but fatigue and painful joints have been reported to last up to several months. Although the disease may occasionally be severe, it is thought to be rarely fatal.

Currently, there is no vaccination or specific treatment for Chikungunya. Treatment is symptomatic. Persons having recovered are likely to be immune from repeat infections.

Where does Chikungunya occur?

The disease occurs in large parts of Africa and Asia, specifically the Indian subcontinent, Thailand, Malaysia, Indonesia, the Philippines, Vietnam, Sri Lanka, and the islands in the Indian Ocean.

Over the last 50 years there have been reported epidemics throughout these regions. The first outbreak in India occurred in 1963 and since then they have had outbreaks throughout the years. One of the largest epidemics occurred in 2006 where over 1.36 million people were infected with the Chikungunya virus. Around the same time, an outbreak occurred on the island of Reunion and 34% of the entire population was infected. Currently in 2008, Malaysia has reported almost 500 cases of Chikungunya fever and Indonesia has reported 520 cases. India continues to be extremely affected by this disease. A current estimation suggests that there are roughly 50,000 people affected by the disease in the Dakshina Kannada district.

Given the widespread distribution of the disease, especially throughout the tropics, and the increase in world travel, there is a high risk of importation of Chikungunya into new areas by infected travelers. This occurred in Italy in 2007, and there was an outbreak near Ravenna with more than 200 people infected.