Documenting COVID-19

Missouri Department of Health and Senior Services delta mask mandate study

Date Updated: December 1, 2021

Date Added: December 1, 2021


On Nov. 1, Missouri Gov. Mike Parson's office requested the state's Department of Health and Senior Services for data showing the effectiveness of mask mandates on COVID-19 case and death rates during the summer and fall 2021 delta variant surge. Two days later, the health department responded with two plot graphs showing the difference in masked jurisdictions (St. Louis and St. Louis County, Kansas City and Jackson County) and the rest of the state, which mostly do not have mask policies.

Principal Subject:
Missouri Department of Health and Senior Services

Highlighted Documents: DHSS masked versus unmasked case rate study results DHSS masked versus unmasked death rate study results

Date Range:
November 1 to November 3, 2021


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Format Details:
.pdf (2 separate files, 4 pages) and .png (attached screenshots of study results)

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Documenting Covid-19