Containment is essential as trends show virus spread increase.
Regardless of reopening plans and dates, it is still a question if in-person instruction will happen in the coming weeks or months.
The decision should be based on whether the virus is sufficiently contained. Current data and trends in Tennessee indicate the answer is no.
TEA monitors daily two key data points for COVID-19: new case rates and active case rates. These measures are part of the data health officials use to make recommendations to school systems.
Baseline measures like these have been used in reopening plans. They, along with other measures, provide data to make school decisions based on science, not politics, economics or other issues.
“Returning to school is important for the healthy development and wellbeing of children, but we must pursue reopening in a way that is safe for all students, teachers and staff,” wrote NEA and the American Academy of Pediatrics in a joint statement. “Science should drive decision-making on safely reopening schools.”
The virus must be sufficiently contained before in-person classes can resume. New and active case rates are important measures to understand if containment has occurred. Here is a quick explanation of each:
NEW CASE RATES
The Tennessee Department of Health and the Centers for Disease Control have set a virus containment threshold of less than 10 new COVID-19 cases per 100,000 people in a 14-day period.
This threshold can be applied to a geographic region or an individual county.
Different Tennessee regions and counties have gone above or below this threshold over the past months and weeks, with a trend of more counties going above during the current virus resurgence.
A daily map is generated by the state health department to show which counties have gone above the threshold. The July 20 map showed the majority of Tennessee’s counties are now above the new case rate.
This map changes daily as new data comes in. At publication, all urban and suburban counties were above the threshold while a handful of rural counties were below.
The map also is a quick indicator that new infections vary from county to county and region to region.
The new case rate threshold is an important tool to view virus containment.
ACTIVE CASE RATES
The active case rate is the percentage of a county’s population with active coronavirus cases.
Some school system reopening plans use active case rates to determine in-person instruction, alternative scheduling, and school closures if they’ve been reopened.
Active case rate thresholds and the decisions tied to them can vary in school system plans, and the methodology in setting those thresholds also varies in the field of public health.
A common active case rate model for schools uses four thresholds:
• No spread with zero active cases,
• Low spread if less than .5% of an area’s population have an active case,
• Medium or intermediate spread if active cases are above .5% and below 1%, and
• High spread if more than 1% of an area’s population.
In a number of school systems’ reopening plans, active case thresholds prescribe actions such as delaying or suspending in- person instruction in a high spread environment or altering schedules during intermediate spread.
Using active case rates has a track record in Tennessee education. Prior to the coronavirus outbreak, several systems called off school because of a rise in flu cases. Suspending school due to illness is common in Tennessee, but with a new, highly communicable and deadly virus, the decision to suspend in-person instruction has much greater stakes.
KNOWLEDGE IS POWER
TEA and its members do not need to be epidemiologists to understand and follow new and active case rates. These simple and important measures provide knowledge to make informed decisions about if or when schools reopen.
It is clear trends in these measures are going in the wrong direction.
When the data indicates the virus has not been contained and is spreading, schools should remain closed. Educators and parents understand new and active case rates are an important part of ensuring data is the basis of sound school decisions.