CDC: In-Person Dining Adds COVID to the Community Menu

Mask mandates were associated with county level decreases in COVID-19 cases, while increases were seen when in-person restaurant dining was allowed, a modeling study found.

The impact of mask mandates showed a protective effect, with daily case and death growth rates declining within 20 days and growing stronger over time, reported Gery Guy Jr., PhD, of the CDC, and colleagues, writing in an early edition of the Morbidity and Mortality Weekly Report.

But rates of daily cases and deaths grew within 40 to 80 days of restaurants resuming in-person dining.

“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,” said CDC director Rochelle Walensky, MD, at the regular White House COVID-19 briefing on Friday. “It also serves as a warning about prematurely lifting these prevention measures.”

Walensky’s comments may have been directed towards states such as Texas and Mississippi, who recently made news when their governors announced that they are dropping mask mandates and allowing “100% reopening,” including businesses at full capacity.

In-person restaurant dining was previously linked with increased transmission of COVID-19, and evidence ties non-pharmaceutical interventions, such as mask wearing, to a reduction in COVID-19 cases.

Guy and co-authors examined daily percentage point growth rate of county-level COVID-19 cases and county-level COVID-19 deaths, using data from state and local health department websites. The team compared data from seven post-implementation time points, ranging from 1-20 days to 81-100 days, to pre-implementation periods as a reference.

The researchers also attempted to control for other factors, such as restaurant closures during the mask mandates, mask mandates in the restaurant reopening models, stay-at-home orders, and bans on gatherings of more than 10 people.

Overall, state-issued mask mandates applied to about three-quarters of surveyed counties. The authors found that within 1-20 days of mask mandates, there was a 0.5 percentage point decrease in COVID-19 case growth rates. Both COVID-19 case and death growth rates saw almost a 2.0 percentage point decline 81-100 days after implementing mask mandates.

Conversely, states allowed restaurants to re-open for in-person dining in nearly all surveyed counties (98%). While the impact was not immediate, COVID-19 case growth rates showed 1.1 percentage point increases 81-100 days later. However, counties allowing in-person dining were associated with 2.2 percentage point increases at days 61-80 and a 3.0 percentage point increase at days 81-100 after restrictions were lifted.

The researchers speculated about why this might be the case, with possibilities including restaurants potentially delaying reopening even after they were allowed to do so, and that patrons might have been more cautious during initial reopenings but more likely to dine at restaurants as time passed.

However, the models did not control for other policies that affect case and death rates, such as other types of closures and physical distancing recommendations, the investigators noted. The model also did not distinguish between indoor and outdoor on-premises dining, adequacy of ventilation, or adherence to recommended public health recommendations and occupancy requirements.

Washington Editor Joyce Frieden contributed to this story.

Last Updated March 05, 2021