Chikungunya, a mosquito-borne viral pathogen responsible for a febrile illness that is usually accompanied by a rash and severe, incapacitating arthralgias, emerged in the Caribbean in October 2013. Since its detection in Saint Martin, chikungunya virus has rapidly spread throughout the Caribbean and to Central and South America, where local transmission has now been documented in El Salvador, Costa Rica, Panama, Venezuela, Guyana, Suriname, French Guiana, Colombia, Brazil, and Paraguay. According to the Pan American Health Organization, as of 6 November 2014, there have been 874 103 suspected cases, 14 703 confirmed cases, and 153 deaths, with many afflicted patients in the Dominican Republic and El Salvador (1). In the continental United States, 1616 imported cases have been reported, with autochthonous transmission in southern Florida. Given the widespread presence of competent mosquito vectors (Aedes aegypti and A. albopictus), it may spread further within the United States.