Declines in County COVID-19 Hospitalization Rates After States Issued Mask Mandates

State-issued mask mandates were associated with a reduction in COVID-19 hospitalization rates across the United States during the early phase of the pandemic. As new variants of the SARS-CoV-2 cause spikes in COVID-19 cases, reimposing mask mandates in indoor and congested public areas, as part of a layered approach to community mitigation, may reduce the spread of COVID-19 and lessen the burden on our healthcare system.

Early in the COVID-19 pandemic, the Centers for Disease Control and Prevention (CDC) recommended a combination of evidence-based strategies to decrease transmission of the SARS-CoV-2 virus. Given that the virus is predominantly spread by inhaling aerosol droplets or aerosol particles from infected individuals, one recommended prevention measure was universal mask-wearing. Following CDC guidance, many states began issuing mask mandates to slow the spread of SARS-CoV-2 in 2020.

Research has demonstrated that these mask mandates were associated with decreases in COVID-19 case and death growth rates. One of our recently published studies has even shown an association between mask mandates and higher rates of consumer spending after states reopened, resulting in an average increase in biweekly consumer spending that was up to $4.46 million higher in counties with state-issued mask mandates. And while some studies have demonstrated the benefits of mask mandates on hospitalization in certain states, less is known regarding their impact on COVID-19-related hospitalizations in all the states that issued mask mandates. Understanding this association is important in the context of COVID-19, as it has been well documented that the early portion of the pandemic caused capacity issues in hospitals across the U.S. Intensive care units (ICUs) had to balance the admission of patients with COVID-19 with non-COVID-19 patients, resulting in shortages of space for patients requiring intensive care. This may be one reason for an uptick in mortality resulting from other prevalent diseases since the start of the pandemic.

In our article, “The Association between State-Issued Mask Mandates and County COVID-19 Hospitalization Rates,” we found that the implementation of state-issued mask mandates was also associated with reductions in COVID-19 hospitalizations in the first year of the pandemic. Specifically, state-issued mask mandates were associated with an average of 3.6 fewer daily COVID-19 hospitalizations per 100,000 people and a 1.2 percentage point decrease in the percent of county beds occupied with COVID-19 patients, 70 days after the mandate’s effective date. In other words, across the states that issued mask mandates in 2020, at least 9,071 COVID-19 hospitalizations may have been averted within two months of those mandates taking effect.

These findings demonstrate that state-issued mask mandates may have helped reduce the burden of COVID-19 on the healthcare sector through averted COVID-19 hospitalizations. This is particularly important as it suggests that mask mandates may have helped “flatten the curve,” allowing ICUs to care for both patients diagnosed with COVID-19 and patients with other serious diagnoses. The reduction in COVID-19 admissions may also have resulted in more favorable economic outcomes to insurers and patients by preventing costly hospitalizations.

Furthermore, we found that this reduction in COVID-19 hospitalizations associated with mask mandates became larger over time, suggesting that these policies were more effective once individuals had time to adjust their behavior and social norms developed. This could also be explained by reductions in secondary transmissions after mask mandates.

As new variants of the SARS-CoV-2 cause spikes in COVID-19 cases, reimposing mask mandates in indoor and congested public areas as part of a layered approach to community mitigation may reduce the spread of SARS-CoV-2 and lessen the burden on our healthcare system. Public health officials may want to consider referencing the CDC’s COVID-19 Community Level dashboard for current information on both their community’s COVID-19 hospitalizations and the potential strains on their local health systems when making decisions about re-implementing community prevention strategies.

For further information, read our article here:

• The Association Between State-Issued Mask Mandates and County COVID-19 Hospitalization Rates

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Christopher Dunphy, PhD, is an economist in the Division of Injury Prevention at the Centers for Disease Control and Prevention (CDC). His work involves the application of quasi-experimental research designs to evaluate the public health and economic impacts of state and federal policies. Dr. Dunphy earned his PhD in Applied Economics from the Ohio State University.

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Heesoo Joo, PhD, is an economist in the Division of Global Migration and Quarantine at the Centers for Disease Control and Prevention (CDC). She has evaluated public health programs and interventions and conducted regulatory impact analyses. Dr. Joo earned her PhD in Economics from the State University of New York at Albany.

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Mathew R. P. Sapiano, PhD, is the Director of Data Science at Lantana Consulting Group and supports the CDC’s National Healthcare Safety Network as a Senior Statistician.

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Mara Howard-Williams, JD, is the former lead of CDC’s Mitigation Policy Analysis Unit. She uses legal epidemiology to examine how law impacts public health throughout the US. Before joining CDC, she focused on the role of culture in global health, recognizing and adhering to international human rights instruments and promoting health as a human right. She also helped global nonprofits maximize their efforts through strategic program planning and evaluation.

Russell F. McCord, JD, is a public health analyst with the Office of Population Health and Policy Analytics (previously with PHLP). His work involves facilitating legal epi work with internal and external partners and providing subject matter expertise on legal and policy issues across various public health topics.

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Gregory Sunshine, JD, serves as a Public Health Analyst with CDC’s Public Health Law Program in the Center for State, Tribal, Local, and Territorial Support. He oversees research on emergency declarations, isolation and quarantine, medical countermeasures, and legal preparedness competencies. He earned a JD from the University of Maryland School of Law and a BA in Political Science from Dickinson College. 

Szu-Yu (Zoe) Kao, PhD, is a Prevention Effectiveness Fellow at the Centers for Disease Control and Prevention. Her work focuses on evaluating health policies and technologies in both chronic and infectious diseases using decision analytical framework to improve population and patient health.

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Gery Guy, PhD, MPH, is a Lead Health Scientist in the Division of Overdose Prevention at CDC. His work focuses on applied research and evaluation in drug overdose prevention. Gery received his MPH in Health Policy and his PhD in Health Services Research and Health Policy from Emory University.

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Regen Weber, JD, MPH, is an attorney based in Dallas, Texas. She holds a JD and a Master of Public Health from Case Western Reserve University and a Bachelor of Arts from the University of Wisconsin – Madison.

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Maxim Gakh, JD, MPH, is an Associate Professor at the University of Nevada, Las Vegas (UNLV) School of Public Health and the Associate Director of the UNLV Health Law Program. His research, teaching, and service center on the intersection of law, policy, and public health.

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Donatus U. Ekwueme, PhD, is the senior economist with  CDC’s Division of Cancer Prevention and Control. His work uses applied economic principles and methods to evaluate public health intervention programs and policies, and to inform decisions on the most effective and efficient ways to allocate health resources to maximize population health.