Mandates to wear masks are linked to a lower number of COVID-19 cases and deaths, according to the Centers for Disease Control and Prevention (CDC).
Researchers compared county-level changes in COVID-19 case and death growth rates relative to mandate implementation.
They found mandates linked to a 0.5 percentage point decrease in daily case growth rates one to 20 days after implementation and decreases of 1.1, 1.5, 1.7, and 1.8 percentage points 21–40, 41–60, 61–80, and 81–100 days, respectively, after implementation.
Researchers also found mandates associated with a 0.7 percentage point decrease in daily death rates one to 20 days after implementation and decreases of 1.0, 1.4, 1.6, and 1.9 percentage points 21–40, 41–60, 61–80, and 81–100 days, respectively, after implementation.
Thirty-nine states and the District of Columbia issued mask mandates starting in April 2020.
“The researchers found that increases in both daily death rates and COVID cases and deaths slowed significantly within 20 days of putting masks mandates into place. And protective effect of the mask mandates grew stronger over time,” CDC Director Rochelle Walensky told reporters during a virtual briefing after the report’s release.
“This report is a critical reminder that with the current levels of COVID-19 in communities, and the continued spread of more transmissible virus variants, which have now been detected in 48 states, strictly following prevention measures remains essential for putting an end to this pandemic. It also serves as a warning about premature lifting these prevention measures,” she added.
Critics questioned whether the link between mask mandates and cases was significant.
“This study basically admits mask mandates and restaurant opening have a negligible impact on spread of COVID. Did anyone at CDC read it?” Julie Kelly, a contributor to American Greatness, wrote in a tweet.
CDC researchers acknowledged that the findings were subject to at least three limitations, including that their models “did not control for other policies that might affect case and death rates, including other types of business closures, physical distancing recommendations, policies issued by localities, and variances granted by states to certain counties if variances were not made publicly available.”
CDC researchers also said there was an increase in daily cases and deaths linked to the reopening of indoor dining at restaurants, though the link wasn’t statistically significant until 41 days after reopening.
“Increases in daily death rates of COVID-19 cases and deaths grew more quickly within 40 to 80 days following restaurants being allowed to resume on-premises dining,” Walensky said.
The report was released after several governors announced the withdrawal of statewide mask mandates as their states recorded sharp drops in COVID-19 cases, hospitalizations, and deaths.
Texas Gov. Greg Abbott, a Republican, also cited how more therapeutics have been developed since last year, as well as the steadily growing number of Texans who are getting COVID-19 vaccines, in addition to nearly 2.5 million residents recovering from COVID-19.
“Remember this: removing state mandates does not end personal responsibility, or the importance of caring for your family members and caring for your friends and caring for others in your community,” Abbott told a briefing. “Personal vigilance to follow the same standards is still needed to contain COVID. It’s just that now, state mandates are no longer needed to stay safe.”