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TALLAHASSEE — Gov. Ron DeSantis will require anyone on a flight from the New York City area to self-isolate for 14 days upon arriving in Florida in an effort to control the spread of coronavirus, he announced late Monday.

In his most drastic move yet, DeSantis will make it a criminal penalty for anyone on those flights to violate the quarantine order. The order applies to all people whose points of departure originate from New York, New Jersey or Connecticut. It takes effect at 12:01 a.m. on March 24.

With more than 20,000 cases, New York leads the nation in the number of people infected with the virus.

“I would reckon, given the outbreak there, that every single flight has somebody on it who is positive for COVID-19,” he said.

Florida Gov. Ron DeSantis is seen during a news conference in this image taken from video courtesy of The Florida Channel [ The Florida Channel ]

On Monday, there were 190 direct flights to Florida from the New York and New Jersey area, he said.

The unprecedented measure is in response to President Donald J. Trump’s refusal to halt domestic travel, DeSantis said. The governor, a close ally of the president, has been asking Trump to limit flights to Florida for more than a week, most recently on Sunday night, DeSantis said.

“That’s the only way we can be sure the virus isn’t going to be reintroduced to the state of Florida,” DeSantis said.

But DeSantis conceded that his order will filter only air travel. Florida isn’t putting any restrictions on people driving into the state with New York license plates. DeSantis said that people in cars aren’t exposing strangers to any kind of contagion the way they might on a plane and there was no obvious way to stopping them. Still, it’s unclear how many New Yorkers would still be allowed to enter Florida under that exception.

DeSantis announced the new restriction during an unusual news conference in Tallahassee that was announced the minute it started, preventing most reporters from attending. A handful of television reporters, whom DeSantis frequently calls on first to ask friendly questions at his news conferences, were apparently given advanced notice to gather in his office at the Capitol.

It also came as a mounting number of public health experts and local and legislative officials were speaking out to pressure DeSantis to issue a temporary, short-term, stay-home order to prevent the spread of the novel coronavirus.

“It is past time to intervene to slow transmission [in Florida,]” said Marc Lipsitch, professor of epidemiology at Harvard T.H. Chan School of Public Health in a call with reporters on Monday.

He and other public health experts warn that it will take three weeks of self-imposed limits on public movement before relief is felt on hospitals and emergency rooms but, without it, more people will die.

DeSantis used the two separate briefings on Monday to make his case that stay-home orders would not be effective in combating the virus.

“You simply cannot lock down our society indefinitely with no end in sight,” DeSantis said. “I can tell you that is not sustainable. That is not something the society would accept.”

During an appearance hours earlier at The Villages in Central Florida, DeSantis used New York as an example of how a stay-at-home order can backfire.

“If you look at what happened in New York, when they did the stay at home order, what did people do?” he said Monday morning. “Well, a lot of people fled the city. ... We’re getting huge amounts of people flying in.”

DeSantis chose The Villages, the nation’s largest retirement community and a GOP stronghold, as a backdrop to tout a new nearby drive-thru testing site in partnership with the University of Florida.

While UF live-streamed DeSantis’ event on Facebook, viewers posted a flurry of comments pleading with DeSantis to severely restrict travel within the state.

“The longer you wait to shut us down, the longer it will take for our state to recover from all of this!” one woman wrote.

With Trump leaving coronavirus response largely up to the states, governors have issued their own lock-down orders and closed non-essential businesses. California, New York, New Jersey, Connecticut, Illinois, Louisiana, Ohio, Oregon, Nevada and Pennsylvania have announced shelter-in-place orders or bans on non-essential businesses.

Moments after DeSantis spoke at The Villages, Massachusetts’ governor ordered all nonessential businesses to close.

Florida, which is experiencing community spread of the virus, has become increasingly an outlier among states, and images of partying spring breakers has led to a national backlash.

Miami-Dade and Broward are the only counties to order all non-essential businesses to close. And while beaches have been closed in some of the largest counties, people were still partying on boats and sandbars over the weekend.

DeSantis mentioned the pandemic scofflaws on Monday and pleaded with them to heed orders to maintain social distancing.

“At the end of the day, you’re going to have a group of people that are not going to comply, that are going to put themselves first,” he said Monday. “I would just say for those folks, you need to cool it.”

America — and Florida in particular — appears to be repeating mistakes made by Italy, which was reluctant to close down restaurants, bars and other businesses as the virus spread. That country appears to be paying a price for its inaction: last week, Italy surpassed China, where the outbreak began, in the number of deaths from coronavirus.

In Florida, the number of cases are increasing at an exponential rate. The state reported 1,171 people infected with the virus as of mid-day Monday. A week ago, there were less than half that many. DeSantis said he expected higher numbers with increased testing.

“We’re expecting that,” DeSantis said. “When you’re expanding testing, you’re going to see more cases.”

He also cited the low number of positive cases in counties across Florida as a sign that he does not need to lock down the entire state.

”We’ve still got 20 counties with zero infections and I think about 26 that have 2, 3, 5, 7 type of infections,” he said.

DeSantis said he wants “good data” to drive his decisions, but the data he’s using is likely inadequate and out of date.

The governor has frequently complained that Florida lacks the equipment and materials to deploy the kind of widespread testing strategy used successfully by South Korea.

The state has conducted just over 13,000 tests in a state of more than 21 million people. Since a person often gets multiple tests, the number of people who have been tested is less than 13,000.

And those test results do not reflect what medical professionals are seeing on the ground, according to a dire letter issued Monday by 75 emergency room doctors, nurses and physicians’ assistants in Miami, the epicenter of Florida’s outbreak.

“The low number of confirmed cases in published reports does not show the true number of people who have been infected by the virus in Miami, or anywhere else in the USA for that matter,” the doctors wrote. “It only reflects where we should be in testing.”

In addition to coronavirus test results, DeSantis said the state is also monitoring emergency room admissions for people with symptoms of the virus, which include fever, coughing and shortness of breath.

It’s not clear whether the state is looking at yet another source of data, which is showing that Florida is experiencing a dramatic spike in fevers, which are one of the earliest symptoms of coronavirus.

Kinsa Health, which makes internet-connected thermometers, said its real-time data indicates that the problem might be much worse in Florida than the test results indicate.

“Related to other states, Florida is a class of its own,’’ the company’s data scientist said last week.

When asked directly on Saturday whether state officials had seen Kinsa’s data, DeSantis and state Surgeon General Scott Rivkees did not answer the question. They instead touted the state’s testing and hospital numbers.

”The most important data we’re looking at is the testing,” Rivkees said Saturday.

On Saturday, DeSantis did propose a change in strategy that has worked in other countries: isolating people who have the virus, but aren’t sick enough to merit hospital treatment.

For weeks, state and federal officials have been telling people who feel sick to stay home. That might be the wrong strategy, however. Data from China indicates that an overwhelming majority of transmissions occur in family clusters, according to the World Health Organization.

“What China started figuring out was, as much as you can believe them, people would get infected, you would send them home and they’d infect the people in their house,” DeSantis said Saturday. “Don’t go back home with your family, because the people you’re most likely to infect are those very close persistent contacts."

DeSantis said they’re evaluating using convention centers and hotels to isolate and monitor people with the virus who don’t require hospitalization. Forcing Americans to isolate themselves could be a tough sell, but Americans could be convinced to do the right thing, health experts say.

Times/Herald Tallahassee Bureau staff writers Mary Ellen Klas and Samantha J. Gross contributed to this story.

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