COLUMBUS, Ohio - Ohio Health Director Dr. Amy Acton for the first time on Thursday put numbers to what had previously been only a model to emphasize the need to “flatten the curve” of coronavirus cases - and offered optimism that the projected peak is getting close to a manageable number.

“We have got to even clamp down more. We have got to stay at home. We can’t go the other direction right now," Acton said during Gov. Mike DeWine’s daily briefing.

Using a graphic from researchers at Ohio State University to demonstrate her point, she noted how things could have been much worse by last week - possibly close to 40,000 new infections a day - had efforts not been made slow the spread of the coronavirus in Ohio.

Instead, the projection from the OSU researchers is that the state is on target for a peak of new cases somewhere in the range of 7,500 to about 9,500 a day, occurring during the first half of April, according to the graphic Acton shared. Action said she hoped the curve peak eventually is in May.

“We have through our collective work together in Ohio decreased that impact on our health care system anywhere from 50% to 75%. That’s crucial, but we have got to do it even more,” Acton said.

She pointed to an area on the graphic in the range of about 6,000 to 7,000 new cases a day to estimate the capacity of the health care system, noting that about 11% of COVID-19 patients end up needing intensive care treatment.

UPDATE: See new Friday update on the curve

Acton said the projections from OSU are the first for Ohio but other researchers, including those at the Cleveland Clinic, are working to refine the estimates.

The state on Thursday reported that the number of confirmed cases had grown to 867. The first three cases were reported March 9.

This graphic shows the daily increase in Ohio coronavirus cases from the first three on March 9 to 867 on Thursday, March 26.Rich Exner, cleveland.com

In the meantime, hospitals have been busy making adjustments to increase their capacities for the anticipated onslaught.

“We will surge. At our peak surge, we may be as high as 6,000 to 8,000 new cases a day," Acton said. "Our hospitals are gearing up that capacity and we are lowering that curve. ... We will exceed our capacity, but we really are minimizing that amount.”

The multi-curve graphic has become a regular discussion point for state and federal officials, and other medical researchers.

The top curve on the graphic models a projection of the worst-case scenario without efforts to slow the spread of the virus. A bottom curve shows what could possibly be done to both reduce the peak and spread out the time period for new cases.

A straight line often shown in the middle is the hospital capacity in a given area. The goal is to stay below that line - or as close as possible.

Dr. Drew A. Harris, a population health analyst at Thomas Jefferson University in Philadelphia, about 10 years ago added the health-capacity line to what commonly was a two-line chart in health circles.

Watching the coronavirus take off, he tweeted a new version on Feb. 28. Since then his three-line chart has attracted wide attention.

“Each community has its own capacity," Harris said during a telephone interview. "If there is a significant outbreak in a small community with a 25-bed hospital, that hospital could be overwhelmed with cases.”

Harris’ version of the curve, like most others, was just a model, without actual numbers for any one area.

Here is the day-to-day percent increase in confirmed Ohio coronavirus cases from March 10 through Thursday.Rich Exner, cleveland.com

Dr. Anthony Fauci, director of the National Institute of Allergy & Infectious Diseases, said during a briefing earlier this month with President Donald Trump: “I can’t give you a firm number on that. The dynamics of outbreaks in some respects are predictable historically. We don’t know because this is unprecedented.”

And Acton said earlier, “Wouldn’t that be a wonderful thing to know the exact number? ... It’s so interdependent on so many things."

The new research Action discussed Thursday began to draw the projections into focus with numbers.

But, Acton noted, more research will be needed and there are lingering unknowns, such as whether spring weather will help slow the number of new cases.

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