COLUMBUS, Ohio — The Ohio Department of Health announced Thursday that Franklin County has been given a Purple Level 4 designation on the Ohio Public Health Advisory Alert System.

On Thursday, Franklin County, which is the state's most populated county, had 45,650 cases of COVID-19, the most in the state, according to the ODH. Cuyahoga County trails with nearly 32,000 cases according to Thursday's numbers.

Level 4 (Purple) is the highest on the advisory alert, and it's for counties where residents have the highest risk of exposure to the coronavirus.

For a county to be moved to a level four or purple status, they need to have six or seven coronavirus indicators for two weeks in a row.

The seven data indicators are:

1. New cases per capita - When the data shows that a county has had an average of 50 cases per 100,000 people over a two-week period, that will trigger a flag for increasing case rate.
2. Sustained new case growth - If the data shows at least a five-day period of sustained new case growth, that will trigger a flag.
3. Proportion of cases that are non-congregate cases - When there are a large number of positive cases from those living in the broader community, more than 50% of new cases originating from non-congregate settings during at least one of the past three weeks, that will trigger a flag on this indicator.
4. Sustained increase in emergency room visits - When there is an increase in the number of people who visit an emergency department with COVID-19 symptoms or COVID diagnoses over a five day period, that will trigger a flag on this indicator.
5. Sustained increase in outpatient visits - When there is an increase over a five-day period in the number of people in outpatient settings, including telehealth appointments, with suspected or confirmed COVID-19 symptoms, that will trigger a flag on this indicator.
6. Sustained increase in new COVID-19 hospital admissions - When the numbers show at least a five-day period of sustained growth in the number of county residents with COVID-19 who are admitted to a hospital, the county will be flagged for meeting this indicator.
7. Intensive Care Unit (ICU) bed occupancy- A county will be flagged for the indicator when the regional ICU occupancy goes above 80% for at least three of the last seven days.

Franklin County has met the following indicators:

• New cases per capita
• New cases increasing
• Non-congregate cases
• Emergency Department visits
• Outpatient visits
• Hospital admissions

The county did not meet the indicator for ICU bed occupancy.

The ODH said that when a county is under a Level 4, residents are asked to only leave home only for supplies and services.

Lake, Lorain and Montgomery counties have all been flagged for the purple Level 4 watch list and could turn purple next week if their situations do not improve.

This week was the first week no counties were at yellow Level 1.

RELATED: What does Purple Level 4 on Ohio's Public Health Advisory Alert System mean?

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