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The number of confirmed coronavirus cases in Florida is doubling every three days, putting the state on a trajectory to see tens of thousands of infections in the coming weeks, a Tampa Bay Times analysis shows.

No rigorous model has been calculated for Florida to predict the disease’s spread in detail. Those usually take months to create.

But at this point, experts say the math is simple. The number of cases is already past the point of easy containment and infections are growing faster and faster, at what statisticians call an exponential rate.

Without dramatic steps, they worry that the epidemic will balloon across Florida and place an unprecedented strain on hospitals and health clinics.

Thomas Hladish, a University of Florida research scientist who specializes in disease modeling and has been advising the state on the outbreak, said that while epidemiologists might disagree on the nuances of their projections, they all agree on the main point.

“We do understand the math and the models well enough to say with great confidence that Florida is going to have a huge public health crisis,” Hladish said. “And we are just at the beginning of it right now.”

By 11 a.m. Saturday, Florida had reported more than 3,700 cases — an increase of nearly 1,000 in 24 hours.

Florida remains one of the few states with a large outbreak not to issue a statewide order to keep residents at home. Several counties across the state, including Hillsborough and Pinellas, issued “safer at home” orders in the last week.

Some public health experts say it will take the more extreme step of shutting down the state to halt the disease’s rapid spread in Florida. Nine hundred Florida healthcare workers had signed a petition by Friday asking for the same thing.

The effects of the intervention wouldn’t be apparent right away. The same is true for the smaller steps that have already been taken in Florida, like social distancing or closing restaurants and fitness studios.

“We are not going to see the benefits for a few weeks, which is frustrating to everyone,” said Dr. Mary Jo Trepka, an infectious disease epidemiologist and professor at Florida International University.

That’s because the statistics take time to catch up with the actual magnitude of the epidemic.

The reason for the lag is twofold.

People who get sick from the virus don’t typically show immediate symptoms of the illness it causes, COVID-19. Research by Johns Hopkins shows 50 percent of patients take five days or longer to develop symptoms. And people often wait another few days to get tested.

The testing process can add extra delays.

Cases show up in the data only after a positive test. Some labs are providing results within 48 hours. But others take a week or more. A Hillsborough County administrator said that results there were taking eight days or longer to process. And the BayCare Health System, one of the leading providers of tests in the Tampa Bay area, has said its results aren’t coming back for about a week.

Deaths, which climbed past 50 Saturday morning, take longer to appear in the data. The people who died recently were likely exposed to the virus in early March.

“What we are seeing today is where the epidemic was three weeks ago,” said José Szapocznik, a professor of public health sciences at the University of Miami’s Miller School of Medicine.

None of the information is captured if people with the disease aren’t tested.

Even though providers across Florida ramped up testing last week, the state has performed only about 40,000 tests. New York leads the country with more than 146,000, according to the COVID Tracking Project.

In Florida, as in the nation, the number of cases has grown almost perfectly in line with the number of tests, the Times analysis shows.

Experts say the low volume of testing nationwide — and the fact that different states have different criteria for who they will test — has made it difficult to get a handle of the size of the epidemic and make state-to-state comparisons.

Without more robust data in Florida, it’s impossible to know how many cases are actually out there.

But knowing the reported numbers are an undercount doesn’t change the alarming shape of the state’s curve.

On some recent days, reports of new cases in Florida have been accelerating as quickly as they were in New York. New York has become the epicenter of the outbreak in the United States. By Saturday afternoon, the state had logged more than 52,318 confirmed cases and 728 deaths.

While the epidemic has progressed differently in the two states and New York has more population density, experts say there’s no reason to expect the number of cases in Florida won’t continue spiking in a similar fashion.

“Quite honestly, if we don’t do anything, we’ll be like New York,” said Szapocznik, who believes a statewide stay-at-home order is necessary.

Reaching New York levels would mean not only a wave of sickness, but a crush of patients in the state’s intensive care units. Some New York hospitals are already approaching capacity.

“Think about it: The hospitals stop functioning because they are overwhelmed. They can’t be able to take care of regular patients,” said Robyn Gershon, a clinical professor of epidemiology at New York University’s School of Global Public Health. “That’s what we’re trying to prevent.”

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