(Based upon *SCDHEC Recent Disease Activity by County Prepared for SCDE)
In order to best guide district decision making concerning the operations of schools, the SCDE collaborated with SCDHEC to develop clear criteria for determining the rate of spread of COVID-19 within a county. This collaboration resulted in the establishment of three measures.
- The first measure, two-week incidence rate, is based upon the number of new COVID-19 cases per 100,000 people for the prior two weeks. Incidence rate is then categorized as follows: Low = 0-50; Medium = 51-200; and High ≥
- The second measure, the trend in incidence rate, is established by determining whether the two week incidence rate is increasing, decreasing, or stable compared to the previous two weeks. For the purposes of this assessment, the trends are considered to be equivalent to Low = Decreasing; Medium = Stable; and High = Increasing.
- The third and final measure, two-week percent positive rate, is based upon the percentage of individuals who tested positive out of the number of individuals tested with a molecular (swab, or PCR) test in the last two weeks for each county. This measure takes into consideration the number of tests performed for residents of the county in the previous two weeks. For this assessment, results are categorized as follows: Low ≤ 5.0%; Medium = 5.1% - 9.9%; High ≥ 10%.
In order to determine the overall assessment for a county based upon these three measures, SCDHEC recommends the following:
- Determine the categorization for the incidence rate, the trend in incidence rate, and the percent positive rate for the county. Consider the following example of ABC County which has the following measures:
1) Incidence Rate = High; 2) Trend in Incidence Rate = High; 3) Percent Positive Rate = High.
- If the rates are the same categorizations, as they are in the example of ABC County, that is the overall assessment. In this particular example of ABC County= High.
- If the rates are not the same categorization, then take the average of them. Consider the following examples:
- Example: DEF County:
1) Incidence Rate = High; 2) Trend in Incidence Rate = High; and 3) Percent Positive Rate = Medium. There are two metrics that are High and one that is Medium, so the disease activity level overall is High.
- Example: XYZ County:
1) Incidence Rate = Low; 2) Trend in Incidence Rate = High; 3) Percent Positive Rate = Medium. There is one metric each that is High, Medium, and Low, so the disease activity level overall is Medium.
View recent SCDHEC Disease Activity information here.