COLUMBUS (WCMH) – Ohio’s progress toward reaching 50 onset cases of COVID-19 per 100,000 people over a two-week period is reversing.

For the first time since mid-January, this rate – which Gov. Mike DeWine has said Ohio needs to hit for state health orders to lift – is increasing. As of Wednesday, March 31, it stands at 168 per 100,000.

State health officials calculate cases per 100,000 people by adding up the onset cases of the previous 14 days, dividing it by Ohio’s 2019 population (11,689,100) and then multiplying that result by 100,000.


Notes

  • Onset cases are backdated to when that COVID-positive person started feeling symptoms. A date’s onset case total is considered preliminary for 14 days as more positive tests come in.
  • State officials subtract the handful of cases that are prisoners. Onset cases among prisoners are not publicly released, so NBC4’s case rate for the state is slightly higher.
  • NBC4’s rate is also rounded up to the next whole number.

    • The rate had been in the 140s last week, but an increase in onset cases in the days since has bumped it up.

    To get back to 50 per 100,000 – a rate the state has not hit since June 14, 2020 – Ohio cannot record more than 5,844 onset cases of COVID-19 over a two-week period. That’s 417 a day.

    During Gov. DeWine’s coronavirus briefing last Thursday, Ohio Department of Health Chief Medical Officer Dr. Bruce Vanderhoff pegged the change in case trajectory on the spreading of more contagious virus variants, as well as the pandemic’s natural shifts.

    “This virus has consistently shown an ebb and flow that has it rising every 90 to 100 days,” he said, “Well, we're at about 90 to 100 days from the last time it did that.”

    When could Ohio hit 50 cases per 100,000 people? When cases were declining consistently in January and February, the simple calculation below sufficed as a non-epidemiological, best-case estimate:

    1. Divide the rate by 50.
    2. Multiply the rate by that result.
    3. Find the last day the rate was closest to that number.
    4. Add that length of time to the current day to get the approximate date the rate gets to 50, assuming consistent decline.

    This simple math got less reliable when cases hit the bottom-right of the bell curve, because the rate of decline was no longer consistent. But now that cases are increasing, it’s unhelpful.

    DeWine has estimated July 4 as a possible date when Ohio hits its goal, but he made that prediction nearly a month ago when cases seemed poised to continue a steady decline.