Using publicly available data from emerging research on COVID-19, this brief was written and reviewed by the Coronavirus-19 Outbreak Response Experts (CORE-19) at the University of Tennessee, Knoxville. It provides insights into comparisons between COVID-19 case rates and spread in Tennessee versus Kentucky.
COVID-19 Cases: Tennessee vs. Kentucky
Policy analysts often compare states with similar characteristics and demographics in order to evaluate the robustness and effectiveness of state-level policy interventions. Comparing Tennessee and Kentucky and their respective responses to the COVID-19 outbreak can shed light on which polices are proving effective and which are not.
As of Wednesday, March 25, 2020, Tennessee has reported:
- 784 confirmed cases of COVID-19, including 53 hospitalizations and 3 deaths, AND
- administered an estimated 11,796 tests for COVID-19 to date, when accounting for both state and non-state laboratories,.
For the same time period, Kentucky has reported:
- 198 confirmed cases of COVID-19, including 4 deaths according to news reports complied by The COVID Tracking Project, AND
- administered an estimated 3,300 tests for COVID-19 to date.
Note: The Kentucky Department for Public Health (DPH) does not currently provide official statistics on the number of hospitalizations or deaths due to COVID-19.
There are several possible reasons for the disparity in cases between Kentucky and Tennessee, including differences in the distribution of the population, testing capability and strategy, and state-level responses and government action.
Population Distribution
Based on 2019 population estimates, Tennessee is nearly 33% larger than neighboring Kentucky with population of 6.8 million compared to Kentucky’s 4.5 million. Likewise, according to 2010 estimates, Tennessee also has a greater population density and urban population:
Such differences in population distribution can impact the geographic spread of disease and the ease with which it can be contained. For example, denser population distributions can lead to greater likelihood of effective contact and therefore disease transmission, as disease spreads more quickly when individuals live in closer proximity to each other.
Testing Capability and Strategy
There are also differences in the volume of COVID-19 tests being administered, and possibly variation in the respective states’ strategies for testing its population.
As of Wednesday, March 25, 2020, Tennessee has conducted an estimated 11,796 tests (including tests administered by both state and non-state laboratories), yielding an approximate positivity rate of 7% (total of 784 positive cases) with the majority of positive cases (61%) occurring among individuals between the ages of 21 to 50 years old.
As of Wednesday, March 25, 2020, Kentucky has conducted an estimated 3,300 tests (KDPH does not specify whether tested administered by non-state laboratories are included in this figure), yielding an approximate positivity rate of 6% (total of 198 positive cases). According to news reports, the majority of positive cases thus far have occurred among individuals between the ages of 50 and 69 years old.
There is a significant difference in the rate of testing among the two states:
- Tennessee: 164 tests per 100,000 residents
- Kentucky: 67 tests per 100,000 residents
The rate at which a state is testing its population is important to consider when comparing cumulative case counts between states, as low testing rates could indicate under-detection of cases.
Likewise, daily case counts can also reflect changes in a state’s testing infrastructure, such as laboratory processing capacity or lag-times in state-level reporting.
Another factor to consider is that individuals living in border counties in each state may travel across state-lines for diagnosis and/or treatment. This would delay reporting to state/county of residence and reduce the number of positives being reported in these areas.
These compounding factors are why state-to-state comparisons should rely on a multitude of metrics, including hospitalizations and deaths, which do not vary according to testing rate and present a direct reflection of the strain COVID-19 is placing on a state’s healthcare system. These additional metrics also provide more insight related to the severity of cases.
State-Level Response and Government Action
There have also been differences in the timeline of the outbreak and the substance of each state’s response to the pandemic. For example, Kentucky issued a state of emergency immediately following their first confirmed case and implemented social distancing policies by closing restaurants and bars to in-person dining more quickly than Tennessee.
Government action has also differed across state-lines. In Kentucky, there seems to be a more unified, statewide response; whereas, in Tennessee, some counties are taking stricter actions than others (e.g., Knox County ‘safer at home’ order announced on March 23).
Here is a brief timeline of the outbreaks:
- March 5: First case reported in Tennessee
- March 6: First case reported in Kentucky; Kentucky declares state-of-emergency
- March 12: Tennessee declares state-of-emergency; Recommendation to close schools in Kentucky
- March 16: Recommendation to close schools in Tennessee; Recommendation to close childcare centers in Kentucky
- March 22: Kentucky announces executive order to close in-person dining; Kentucky announces executive order to close non-essential businesses (otherwise known as shelter-in-place); Tennessee announces executive order to close in-person dining
As of Wednesday, March 25, 2020, Tennessee has not issued a statewide recommendation to close childcare center or issued an executive order to close non-essential businesses.