Staff photo by C.B. Schmelter / Lindsay Blum crosses the Walnut Street Bridge on Thursday, Aug. 6, 2020 in Chattanooga, Tenn. Blum, from Houston, Texas, was visiting because her husband had a job interview.

In some parts of Tennessee, including Hamilton County, the trend of new daily COVID-19 cases shows signs of improving, indicating that public health interventions such as public face mask mandates may be helping to slow the growth of some local outbreaks.

New cases began to surge in Hamilton County in early July and in the week following the July Fourth holiday, prompting Hamilton County Mayor Jim Coppinger to implement a mandate requiring people to wear face coverings in most public settings.

Health officials said at the time it could take several weeks before results of the mandate were reflected in the data, since it can take between two and 14 days for people to experience coronavirus symptoms after exposure, plus more time to seek testing and receive results.

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Hamilton County's mask mandate

From July 14 to 31, Hamilton County averaged 107 new COVID-19 cases per day — higher than any other point throughout the pandemic. But after the first week in August, the weekly average fell to 70 new cases per day, according to data from the Hamilton County Health Department.

Hamilton County's decline in new cases doesn't appear to be a result of less testing. Two weeks ago, on July 24, the county averaged 1,120 tests for the week. The seven-day average for tests in the county as of Friday was 1,173.

Melissa McPheeters, a health policy research professor at Vanderbilt University Medical Center, said "it's absolutely possible that it is that mask mandate that is having an effect."

That would reflect what's happening in other areas of the state and country where face masks are required, she said.

"In a lot of parts of Tennessee, we are starting to see either a plateauing or a reduction [in new cases]," McPheeters said. "You want to share the good news, but you also want to be careful to not say, 'Oh we made it. Let's throw away the masks.'"

"This should give us incentive to keep doing that important work and keep moving in that right direction," she said.

While new cases are an important metric for tracking the pandemic, they should be looked at along with other data points, such as hospitalizations and deaths. That's because not everyone with coronavirus will get tested or show symptoms.

Spikes in hospitalizations and deaths typically follow in the weeks or month after a surge in new cases. The number of Hamilton County residents hospitalized with COVID-19 has hovered in the low 40s since July 30.

On Friday, the county reported three new deaths, bringing the total number of deaths in the county this week to five and since the pandemic began to 53.

This week's fatalities included two Black men, one age 61-70 and another age 71-80, with underlying health conditions; one Black woman age 61-70 with no underlying conditions and who was asymptomatic at the time of testing; and a 71- to 80-year-old white man with multiple underlying conditions.

Becky Barnes, Hamilton County Health Department administrator, said in an email Friday that she agrees the mask mandate is helping reduce the spread of disease and driving new cases down — however, "we are still having spread at large gatherings and failures to wear masks."

"Yes, we believe that the mask directive is having an effect on slowing the spread of the virus in our community. But social distancing is also very important, as is hand washing and staying home if you test positive or are sick," Barnes said.

This week in Alabama, health officials said they are cautiously optimistic as the reported number of daily COVID-19 cases fell to under 1,000. The state was reporting as many as 2,000 new cases per day last week. Alabama Gov. Kay Ivey issued a statewide order in mid-July requiring face coverings in public.

Tennessee Gov. Bill Lee has taken heat from physician groups, teachers and other advocacy organizations over his decision to leave the decision over whether face masks are required to county mayors as opposed to issuing a statewide mask mandate.

McPheeters said on Thursday that between 60% and 70% of the state's population is now under a mask mandate, although some of those mandates are so new that their impact has yet to be seen. Those mandates are also concentrated in the state's more populated areas, meaning most Tennessee counties still don't require face coverings, and there are still many areas where COVID-19 transmission shows no sign of slowing.

"I think sometimes we want to believe that in more rural communities we might be a little bit safer," she said. "But the fact of the matter is, COVID-19 has now entered every county, and so we all have to be really careful."

Since mid-July, coronavirus cases and hospitalizations have increased in areas outside of Tennessee's largest metro areas, yet appear stable in Nashville and Memphis, according to a report from Vanderbilt's School of Medicine and University Medical Center released Tuesday. Nashville and Memphis in June became the first major cities in the state to require face masks.

McPheeters said that declines in new cases can also be explained by people changing behaviors on their own as a result of case surges. For example, Hamilton County had another — smaller — spike in cases in early June that slowed down at the end of the month before resurging in July.

"Even in the absence of a mandate, people will change their behavior when they're concerned about high rates of infection. We saw that at the beginning epidemic," she said. "I don't think that's enough to get us where we need to be. I'm a proponent of mask mandates, because I just think it makes it easier for people to do the right thing. But we do see that to some degree."

Contact Elizabeth Fite at or follow her on Twitter @ecfite.