The person lives in West Palm Beach County about 70 miles (113km) north of the initial transmission zone.
Florida Governor Rick Scott said the state officials still believe that active transmission zone for the virus is one square mile (3sq km) in Wynwood neighbourhood in North Miami.
The infected person had recently travelled to the Miami area.
The Centers for Disease Control and Prevention previously issued a travel warning for the neighbourhood, particularly focused on pregnant women.
The virus is known to cause a severe birth defect called microcephaly, which can infants to develop abnormally small heads.
With the school year about to begin, Governor Scott said the state is sending mosquito repellent to school districts in affected and neighbouring counties.
The outreach covers primary school through public universities.
In Miami, where 16 locally transmitted cases of Zika have been confirmed, the state has sprayed against mosquitoes and tried to remove standing water, where the insects breed.
They've also encouraged the public at large to use insect repellent on their own.
The Florida Department of Health is investigating another case of Zika contracted in the state.