Tennessee areas without mask requirements have higher death toll per capitaNov. 10, 2020, 10:12 AM
by Jake Lowary
Tennessee areas where mask requirements were instituted over the summer have substantially lower death rates due to COVID-19 as compared to areas without mask requirements, according to a new analysis by Vanderbilt Department of Health Policy researchers.
The analysis, led by John Graves, PhD, associate professor of Health Policy and director of the Vanderbilt Center for Health Economic Modeling, finds that deaths per 100,000 population in the 67 counties that never required masks rose to a rate more than double the 28 counties that began requiring masks at some point between July 1 and the first week of August.
“This analysis makes clear that a set of policies including mask mandates can save lives,” Graves said. “We know that mask mandates are associated with mask wearing and other behaviors more likely in those communities, and the combined effect of these policies is clear and substantial.”
The study uses data on COVID-19 deaths by date of death, which is earlier than reported by the state, up to Oct. 1. The analysis reflects deaths that were tied to infections in mid- to late September, before the recent surge in cases of COVID-19 in Tennessee.
The analysis expands on other analyses that Graves, along with Melinda Buntin, PhD, Mike Curb Chair of the Department of Health Policy, and Melissa McPheeters, PhD, MPH, research professor of Health Policy and Biomedical Informatics, have conducted about the implementation of mask requirements and hospitalizations.
As of Nov. 10, approximately 63% of the state’s residents lived in areas where a mask is required, while the remaining 37% live in an area where masks were either never required (8%) or live in areas where mask requirements expired.
Death rates were initially higher in the areas where masks became required, the analysis found. In the weeks after mask requirements were put in place, areas where masks were required showed sharper declines in deaths per 100,000 population compared to areas where masks were never required.
“Deaths are a lagging indicator, following increases in cases and then hospitalizations, so we expect any intervention such as a mask requirement to take some time to demonstrate effectiveness. Rising rates of COVID-19 are a big ship to turn, and it is important to act early enough to be effective,” McPheeters said.
“As of the first week of October, there were more than four deaths per 100,000 population in areas where masks were never required and near or below two deaths per 100,000 in areas that adopted a mask requirement over the summer,” Buntin said.
The good news, researchers noted, is that more than 80% of Tennesseans were reporting as of Nov. 5 that they are wearing masks, according to research cited in the analysis from Carnegie Mellon University. The analysis notes, however, that mask wearing may be inconsistent, especially when around close family and personal contacts.
“Individuals may not understand the risk of exposure to friends and family and may ‘let down their guard’ in situations where they are meeting in small groups with close contacts,” the researchers concluded. “Mask ordinances demonstrate leadership by sending a clear signal that behavior must change to mitigate spread of the virus.”