HORRY COUNTY, S.C. (WBTW) — Dillon, Horry, and Marion counties have been moved into the “high” COVID-19 incidence rate category as of information released by the South Carolina Department of Health and Environmental Control on Tuesday.

The three counties join Sumter County, which had been in the category for multiple days. Except for Marlboro and Saluda counties, the rest of the state remained in the “moderate” category.

The incidence rate is calculated using the number of new, confirmed COVID-19 cases reported to the state over a two-week period, per 100,00 people.

Last month, all but two of the state’s counties were categorized as having a “low” incidence rate. 

Dillon County’s rate was 213.3 new cases per 100,000 people, Horry County’s rate was 214.1, Marion County’s rate was 225.1 and Sumter County’s rate was 286.7. 

A “low” incidence rate is considered to be fewer than 50 cases per 100,000 people over a two-week period, a “moderate” rate is between 51 and 200 cases, and a “high” rate is more than 200 cases. 

The downgrade came the same day that DHEC announced 827 new, confirmed cases statewide, 272 probable cases and one confirmed death. Of 9,856 new cases reported to the state, 10.6% were positive for the virus.

Horry County had the second-highest number of new cases reported Tuesday, with 84. It was beaten only by Richland County, which had one more case than Horry County. Horry County had topped the list multiple times over the last two weeks as the delta variant of the virus continues to spread. 

Tuesday’s update brings the state’s totals to 502,094 confirmed cases, 109,500 probable cases, 8.716 confirmed deaths and 1,167 probable COVID-19 caused deaths.