Chikungunya was probably brought to the United States by travelers who became infected abroad and were subsequently bitten by Florida mosquitoes, which transmitted it to the other victims.
The virus has spread rapidly across the Caribbean and Central America since it was first detected in the Western Hemisphere last December.
The Dominican Republic, Haiti, Guadeloupe and Martinique have been especially hard-hit.
But the disease is also spreading across central America and northern parts of South America.
Since two species of mosquito that can carry the virus are common across a wide area of the United States, some doctors warn chikungunya could spread along the Gulf Coast later this summer or next year.
The virus causes rash, fever and severe joint pain that can linger for years in some cases.
There is no cure, but the pain can be treated. Health officials caution that the only way to combat the virus is to control the mosquito population.