CLARKSVILLE, Tenn. (CLARKSVILLENOW) – Montgomery County saw a drastic drop in the calculated number of active COVID-19 cases on Thursday, Sept. 3, after the Tennessee Department of Health implemented a new formula and corrected a zip code error.

On Wednesday, Sept. 2, there were 1,038 active cases reported in Montgomery County, a number that has stayed above 1,000 since early August.

A day later, on Thursday, Sept. 3, that reported number plummeted to only 195 active cases.

Why the drastic drop?

Joey Smith, director at the Montgomery County Health Department, said they have been waiting in anticipation for these corrected “active cases” numbers.

“Early in the COVID-19 outbreak, public health staff members conducted ongoing individual follow-up with cases to accurately answer the question, ‘Has this case recovered?'” Smith said. “As case volume increased and long-term individual follow-up was not feasible, TDH began applying a 21-day automatic cutoff for this question.”

The number of active cases was calculated by subtracting the number of recoveries and deaths from the total number of cases.

Previously, the Tennessee Department of Health considered a case recovered after 21 days.

But TDH announced on Sept. 3 they will begin to show that “inactive/recovered” cases will include people who are 14 days or more beyond their illness onset date (or, for asymptomatic cases, their specimen collection date).

“This will more closely align with what is now understood about the infectious period of COVID-19, as recent data from the Centers for Disease Control and Prevention show most patients with COVID-19 are no longer infectious after 10 days,” TDH said in a news release.

Zip code corrections

Statewide, there are about 1,700 cases for whom the county of residence needed to be corrected. For these individuals, the county does not correspond correctly to their street addresses, Smith said.

“Positive case tests come from all over the world, pediatrician offices, clinics, etc., so zip codes that border a county may go incorrectly to another county,” Smith said. “This discrepancy can occur when a laboratory report contains incorrect county information. Some laboratory systems automatically assign county information based on an individual’s ZIP code. Because some ZIP codes straddle county lines, the assigned county may be incorrect.”

Smith said the corrected active cases and zip code corrections data will help not just their agency, but several others such as the school system to make decisions based on updated COVID-19 numbers.

New reports

Starting Sept. 3, individual County Data Snapshots will provide information on case counts, hospitalizations, testing and more for each county at www.tn.gov/health/cedep/ncov/data/county-data-snapshot.html.

By the numbers

Here are the updated Montgomery County numbers as of 2 p.m. Thursday, Sept. 3:

  • 2,536 total cases since March 6
  • 195 active cases
  • 52 school age cases in last 14 days
  • 103 total hospitalizations
  • 30 total deaths
  • 32,360 total negative lab results