Thousands of travelers to the Caribbean and nearby regions are coming home with an unwanted souvenir: a mosquito-borne virus that recently settled there.

The virus is called chikungunya (chih-kihn-GOON'-yuh). It can cause severe, often disabling joint pain, fever, rash and other problems.

Few U.S. doctors have ever seen a case and many are stumped by the symptoms. More than 2,300 U.S. travelers to the Caribbean and parts of Latin America, South America and Mexico have caught the virus since last May.

There is no vaccine or treatment except medicine for pain. To prevent infection, doctors recommend keeping arms and legs covered and using bug repellent with plenty of the active ingredient, such as DEET.

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