Briceville zip code has highest case rate in Anderson County

The 21-day COVID-19 case rates for an East Tennessee region outside Knox County, the white area at center, through Wednesday, July 22, 2020. The main Oak Ridge zip code, on the lower northwest side of Knox County, is 37830. The main Clinton and Marlow zip code is 37716. Powell, Claxton, and Heiskell are 37849. The main Oliver Springs zip code is 37840. Rocky Top is 37769, Briceville is 37710, Norris is 37828, and Norris and Andersonville is 37705. Lenoir City and Oak Ridge is 37771. The 37748 zip code is Harriman, Blair, Coalfield, and Oak Ridge. The 37763 zip code includes Kingston and Midway,. (Image by Tennessee Department of Health)

Note: This story was last updated at 7:15 p.m.

The Briceville zip code had the highest rate of COVID-19 cases in Anderson County, calculated compared to population, according to maps posted by the Tennessee Department of Health on Wednesday. The Briceville zip code is 37710.

The Oak Ridge and Elza (37830), Clinton and Marlow (37716), and Rocky Top (37769) zip codes had lower case rates than the Briceville zip code.

Still lower were the Oliver Springs and Coalfield (37840), Powell and Claxton (37849), Heiskell (37754), Norris (37705), and Norris and Andersonville (37705) zip codes.

On July 7, Bill Christian, spokesperson for the Tennessee Department of Health, said there wasn’t one large cluster of cases that explained the increase in cases in Anderson County. Oak Ridge Today asked about that after the number of new cases started to increase in the county starting around July 2.

“Like much of East Tennessee, Anderson County is experiencing an increase in community transmission,” Christian said at the time.

“We strongly encourage Tennesseans to continue wearing a mask and social distancing to reduce transmission,” Christian said.

The Tennessee Department of Health hasn’t published the exact number of cases per zip code, but the department has published 21-day case rate maps. The maps, last published on Wednesday of this week, display case rates in ranges, measured as rates of confirmed and probable cases per population by zip code.

It’s not clear how many people live in the Briceville zip code and how that compares to the population of other zip codes, such as Oak Ridge’s. But the population of the Briceville zip code would presumably be considerably smaller than the population of the Oak Ridge zip code, so a smaller number of cases there could lead to a higher rate, at least compared to total population.

The Kingston and Midway zip code (37763) had a case rate with a range as high as the Oak Ridge zip code, according to the maps.

The Lenoir City zip code (37771) had a case rate range higher than the Oak Ridge zip code. It was in the same range as the Briceville zip code, according to the Tennessee Department of Health rate maps.

Here is how the Tennessee Department of Health calculates the rates, which are based on confirmed and probable cases per 100,000 people per zip code:

“We use ‘per 100,000’ as a way to standardize rates across different population sizes and use this measurement for reporting rates of many other illnesses that we track,” TDH spokesperson Shelley Walker said Friday. “Itâ€™s no problem for this measurement to be used for zip codes of smaller population sizes. In fact, we expect many Tennessee zip codes are less than 100,000 people. See the table below for an example. The rates are basically a way to easily show how the same raw number of cases can mean a different thing in areas of different population densities.”

Ten cases in a zip code of 10 people would be significantâ€”a “big deal”â€”while 10 cases in a zip code of 10,000 people would be less significantâ€””less of a big deal,” Walker said.

# of Cases	Population of Zip Code	Doing the math	Rate per 100,000
10	10	10/10*100,000	100000
10	100	10/100*100,000	10000
10	1000	10/1000*100,000	1000
10	10000	10/10000*100,000	100

Here are the ranges of the 21-day case rates in Anderson County and a few nearby areas through Wednesday:

Highest rate of five ranges

Briceville (37710)
Lenoir City, Oak Ridge (37771)

Second-highest

Oak Ridge, Elza (37830)â€”the main Oak Ridge zip code
Clinton and Marlow (37716)
Rocky Top (37769)
Kingston, Midway, Oak Ridge (37763)

Second-lowest

Powell, Claxton, Heiskell (37849)
Oak Ridge, Solway, Karns (37931)
Oliver Springs, Coalfield (37840)
Harriman, Blair, Coalfield, Oak Ridge (37748)
Norris (37828)
Norris, Andersonville (37705)
Farragut, Knoxville, Oak Ridge (37932)

The case rate trends on Wednesday, July 22, appeared similar, but not identical to, the case rate trends on Wednesday, July 15. The Briceville zip code also had the highest case rate in Anderson County at that time.

They are different than the case rates on July 2, when the highest case rates were in the Norris and Norris and Andersonville zip codes.

Here are the East Tennessee testing rates, excluding Knox County, through Wednesday, July 22: