The infected individuals are residents of Hillsborough and Manatee County, both near the Tampa Bay area. Officials said the Hillsborough County resident has a history of traveling to Italy, while the patient from Manatee County has no travel history to any of the CDC-restricted countries.
"It is necessary and appropriate to take action to ensure that COVID-19 remains controlled and that residents and visitors in Florida remain safe and secure," DeSantis said in a statement.
Both patients are in isolation and actively being monitored by the Florida Department of Health. They will remain there for at least 14 days or until they test negative for COVID-19. He designated the department as the lead state agency to coordinate an emergency response.
"Tomorrow I will be in Tampa and Miami with Surgeon General Rivkees and other officials to discuss our continued statewide response on #COVID19," DeSantis tweeted at 9:43 p.m. He directed Rivkees to declare the emergency.
DeSantis referenced CDC recommended measures including voluntary home isolation when sick, covering coughs and sneezes, disposing of tissue waste properly and washing hands often with soap and water for at least 20 seconds.
Earlier on Sunday, Florida Sen. Marco Rubio said it's "not a question of if but when confirmed cases of coronavirus are found in Florida."
"We must provide accurate information on best ways to prevent it from spreading and prioritize resources to help health care workers, the elderly & those with preexisting health conditions," he added.
Rubio issued a statement after the positive cases were found.
"The health and safety of every Floridian, especially the elderly and those with compromised immune systems, remain my highest priority," he said. "I will continue to work with the Trump Administration and Governor DeSantis to ensure our state has the resources and information it needs. I am working with my colleagues in Congress on a funding package to ensure Florida has every available federal resource to respond to the coronavirus, and I look forward to its swift passage in the coming weeks.”
Rhode Island declared its second positive test on Sunday in a person who recently returned from Europe, while a third person from the trip is undergoing tests, health officials said. They are all from the same trip that saw the state's first positive case hours earlier.
The man in his 40s tested positive after traveling to Italy in mid-February. Dozens are in self-quarantine and the high school that organized the trip is closed for sanitization, according to the Rhode Island Department of Health.
Italy has seen 1,694 cases of the coronavirus as of Sunday, a jump of 50 percent in just 24 hours. The country has seen 34 deaths from the virus so far, with five more recorded since yesterday.
The Associated Press contributed to this report.