There are currently 12 people diagnosed with the Zika virus in Florida, up from nine people on Wednesday, Scott said during a news conference. The five counties under a state of emergency are Broward, Miami-Dade, Hillsborough, Lee and Santa Rosa.
All of those diagnosed were infected while out of the United States, in areas where transmission of the Zika virus is ongoing, Scott said.
"We can prepare for the worse and hope for the best," Scott said. "We are going to do everything we can to stay ahead of the Zika virus."
There have been no reported case of mosquitoes transmitting the Zika virus to people in Florida.
Scott said the state is working with the CDC to get more tests that allow doctors to determine if a person has ever been infected with the Zika virus, and to help educate health providers in the state about the virus and its effects.
Scott said he wanted to get 1,000 tests from the CDC that test for antibodies for the Zika virus, so that any pregnant women who were in Zika-affected countries can get tested to see if they were actually infected.
Additionally, he is directing the government to purchase 4,000 tests that allow doctors to diagnose an active infection of the virus, so that a larger outbreak could be quickly identified.
Scott dismissed questions from reporters that his actions could make tourists wary about visiting the state if they are concerned about the Zika virus.
"I don’t think it’s scaring people. It’s telling people that you’re state government is going to be prepared," Scott said.