The CDC said the state is the lead on the case, which involves someone with no travel history to a country with active Zika transmission. Florida public health officials have confirmed Zika infection through laboratory testing.
Florida, Texas and other parts of the Gulf Coast are considered at highest risk of local transmission of the mosquito-borne virus. The region is home to the Aedes aegypti mosquito, the primary vector for transmitting Zika. Florida has also had local cases of dengue and chikungunya, related viruses that are spread by the same mosquito species. Florida already has 326 travel-related Zika cases, including 88 in Miami-Dade, the most in the state.
None of the 1,306 cases of Zika that have been reported so far in the continental United States and Hawaii have been the result of local mosquitoes.
But health officials have been bracing for local transmission of Zika across the South and parts of the Southwest during the peak summer months. Florida Gov. Rick Scott (R) has repeatedly appealed to the Obama administration for additional resources so his state could be prepared when cases began to surface.
In a statement late Tuesday, the CDC said it has provided Florida more than $2 million in Zika-specific funding and about $27 million in emergency preparedness funding that can be used toward Zika response efforts.
The virus can also be spread through sexual contact, but the health department statement did not specify how the individual involved was believed to have been infected.
"We're looking into all non-travel related transmission at this point," said Mara Gambineri, a health department spokeswoman.
The statement said the department would be providing Zika prevention kits and repellent in the county and in the area of investigation.
Congress left town last week without finalizing legislation to combat the virus, much to the dismay of public health officials, infectious disease experts and children's advocates. Health officials have warned that the $589 million the Obama administration redirected from fighting Ebola to combating Zika this year is insufficient and that lawmakers' failure to approve new funding is holding up work on a vaccine, improved diagnostics to test for Zika and research on the long-term consequences of the virus during pregnancy.
Health and Human Services Secretary Sylvia Burwell and Office of Management and Budget Director Shaun Donovan wrote Republican leaders last week saying that the inaction on a Zika package "will significantly impede the Administration’s ability to prepare for and respond to a possible local transmission in the United States and Hawaii and address a growing health crisis in Puerto Rico.”
The Florida news comes one day after Utah officials said they were investigating possible person-to-person transmission from an elderly man to a caregiver.
Most people infected with Zika have no symptoms or only mild ones. But the virus can cause severe birth defects in pregnant women, including microcephaly, a rare condition characterized by an abnormally small head and serious brain damage.