Coweta County is at more than double the incidence rate for high transmission of COVID-19, according to data from District 4 Public Health.
District 4 representatives presented the data at Thursday’s called meeting of the Coweta County Board of Education, which unanimously approved a plan for all students to start school virtually on Aug. 13. School officials have been working with District 4 and other agencies to craft a reopening plan.
Community transmission risk is divided into four categories: low (0-10 cases); moderate (10-50 cases); moderately high (50-100 cases) and high (100 or more cases). During its most recent two-week tracking interval, the DPH reported 221 new cases of COVID-19 infection in Coweta County.
“That’s well over double the threshold for high spread in the county,” said Ashton Harris, District 4 chief epidemiologist.
To help the school system plan, Harris said she and her team – which also included Xavier Crockett, emergency management specialist, and Alex Wright, an epidemiologist – mapped 14-day incidence rates from the earliest confirmed cases of COVID-19 in Coweta County, which has a population of around 150,000.
“We used that to illustrate kind of where we are and where we’re going,” she said. “Since mid-June, we’ve been at the threshold or above the substantial community transmission level. And really, we’re only seeing it continue to grow.”
Harris said the level of transmission is based on new cases divided by the population. It includes data for ages 5 and older.
“It’s really representative of each community, each county,” she said.
The DPH uses a four-week forecasting model that is based on current social distancing and mask-wearing practices in a community.
“Obviously, if we move forward and that changes, the modeling will change and reflect that,” Harris said. “Really, we’re only seeing it increase in cases per capita moving forward into August.”
Social distancing and mask-wearing practices are collected at both the county and state levels, Wright said.
“As a state, Georgia is not doing great with the mask-wearing and social distancing,” she said. “Coweta is doing average. But let’s say you wake up tomorrow and just all of the sudden, people start wearing their masks … you’ll see that model change overnight.”
“We can tell by the numbers whether or not the citizens in the county are doing the social distancing or they’re wearing their masks when they’re going out by those rates, whether they’re going up or down,” Crockett said.
Board member Linda Menk asked if the increase in COVID-19 cases is the result of an increase in the number of tests being performed.
“Isn’t a lot of this the result of more and more testing being done?” Menk asked.
Wright said in a county with a relatively small population, such as Coweta, the effect of increased testing on the data would be minimal.
“It would be a very, very small change overall if you do the math,” she said. “(The data) is representative of your average population here, so you wouldn’t see a huge change based on that testing number. If you were a larger population, you would, but because you’re 150,000, which is not huge, that number is not going to be significant.”
Horton asked about the significance of recent numbers.
“Based on the changes that you’ve seen in the numbers, are those what you would consider substantial changes in the numbers over the last month?” he said.
“Yes,” Wright said. “Even in the past two weeks, the increase in cases has been alarming. We’re seeing that across the board in all of our counties in District 4, and really, statewide.”
Board member Andrew Copeland asked if there is any truth to the idea that children are not as affected by COVID-19 as adults.
“We’re starting to see more and more youth cases,” said Harris, who attributed the rise to the return of some athletics and camps. “We’ve seen so many camp-based outbreaks.”
Beth Barnett, board vice chair, asked about lag time in data.
“Really, it’s that two-week interval, and that’s why we’re using that,” Harris said. “Someone is exposed, then becomes ill, gets tested, and then it comes back in to be reported to us and we do the contact tracing. So that two-week delay is really how long it takes to reflect the data.”
Harris said the DPH accurately predicted an increase in cases about two weeks after the July 4 holiday, for instance.
“We knew about mid-July we’d see the results of the Fourth of July numbers, and we definitely have,” she said.
Horton asked about a projected spike in cases in August.
“Your modeling projects a mid-August peak? Or is that a late-August peak?” he asked.
Wright said the most recent four-week data projection shows a peak around Aug. 25, but that as school resumes in Georgia and other states, a new data set will emerge and allow a “tighter” model.
Harris said those numbers are not necessarily a peak.
“Really, I wouldn’t call it a peak,” she said. “It’s just where we see the cases going. Honestly, it could increase higher from that, so the use of the word ‘peak’ is a little misleading. Right now, we’re just seeing a projected increase.”