Even as officials in Texas and Mississippi lifted mask warrants statewide, researchers at the Centers for Disease Control and Prevention on Friday offered new evidence of the importance of headgear, reporting that the warrants mask wear were linked to fewer coronavirus and Covid infections – 19 deaths in counties across the United States.
Federal researchers also found that counties opening restaurants for on-site dining – indoors or out – saw an increase in daily infections about six weeks later, and an increase in Covid death rates. -19 about two months later.
The study does not prove cause and effect, but the results are consistent with other research showing that masks prevent infection and that indoor spaces promote the spread of the virus through aerosols, tiny respiratory particles that persist in the air.
“You have a decrease in cases and deaths when you wear masks, and you have an increase in cases and deaths when you dine out in person,” CDC director Dr. Rochelle P. Walensky said on Friday. “And so we would be arguing for policies, certainly while we’re at this plateau of high caseloads, that would listen to this science of public health.”
On Friday night, the National Restaurant Association, which represents one million restaurants and food outlets, criticized the CDC’s study as “an ill-informed attack on the industry hardest hit by the pandemic.” He pointed out that the researchers had not controlled for factors other than dining out – such as business closures and other policies – that could have contributed to coronavirus infections and deaths.
“If a positive correlation between ice cream sales and shark attacks is found, it would not mean that ice cream causes shark attacks,” the association said in a statement.
The group also criticized federal researchers for failing to measure adherence to safe operating protocols, and noted that the research did not distinguish between indoor and outdoor dining, or whether restaurants had adhered to distancing recommendations or had adequate ventilation.
“It is irresponsible to pin the spread of Covid-19 on a single industry,” the association said.
The findings come as city and state officials across the country grapple with increasing pressure to reopen schools and businesses as the rate of new cases and deaths declines. Authorities recently authorized dining in New York. On Thursday, the Connecticut governor said the state would end capacity limits later this month at restaurants, gyms and offices. Masks are always required in both locales.
“The study is not surprising,” said Joseph Allen, associate professor at the TH Chan School of Public Health at Harvard and director of the university’s Healthy Buildings program. “What’s surprising is that we are seeing some states ignore all the evidence and open up quickly, remove the mask warrants and open a full dining hall.”
Other researchers said the new study confirmed the idea that viral transmission often takes place through the air, that physical distance may not be enough to stop the spread in some settings, and that masks at least block in part airborne particles.
President Biden’s health advisers have said in recent days that now is not the time to relax. As of Thursday, the seven-day average of new cases was still 62,924 per day, according to a database maintained by the New York Times.
Although that figure is down 14% from two weeks earlier, new cases remain close to the peaks reported last summer. Although deaths have started to decline, in part due to vaccination campaigns in nursing homes, it remains common for 2,000 deaths to be reported in a single day.
Mr Biden on Wednesday criticized decisions by the governors of Texas and Mississippi to lift statewide mask mandates and reopen businesses without restrictions, calling the plans a “big mistake” reflecting “Neanderthal thinking. “.
The president, who asked Americans to wear masks during his first 100 days in office, said it was essential for officials to follow the advice of doctors and public health officials as the vaccination campaign against the coronavirus is gaining momentum. As of Thursday, around 54 million people had received at least one dose of a Covid-19 vaccine.
“It may seem tempting, in the face of all of this progress, to try to get back to normal as if the virus is in the rearview mirror,” White House pandemic adviser Andy Slavitt said on Friday. “It’s not.”
CDC researchers looked at associations between mask warrants, dining at indoor or outdoor restaurants, and coronavirus infections and deaths last year between March 1 and December 31. and the dead.
Infections and deaths declined after counties mandated mask use, the agency said. Daily infections increased about six weeks after counties allowed restaurants to open for dining there, and death rates followed two months later.
The authors of the report concluded that mask warrants were linked to statistically significant decreases in coronavirus cases and death rates within 20 days of implementation. Dining in restaurants, indoors or out, was associated with increased case and death rates from 41 to 80 days after reopening.
“State mask warrants and a ban on on-site eating in restaurants help limit potential exposure to SARS-CoV-2, reducing community transmission of Covid-19,” the authors wrote.
Shortly after the report was released, the CDC amended it, urging establishments that resume serving diners to follow agency guidelines to reduce transmission in restaurants.
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“The message is that if restaurants are to open their doors for on-site dining, it’s important to follow CDC guidelines for doing so safely and efficiently,” said Gery P. Guy, team scientist. Covid intervention from the CDC and corresponding study author. .
This includes “everything from staff staying at home when they show signs of Covid or have tested positive or have been in contact with someone who has Covid, and requiring masks among employees as well as customers who don’t actively eat or drink, ”Dr. Guy mentioned.
Other steps include adequate ventilation, options for eating outside, spacing customers six feet apart, encouraging frequent hand washing, and sanitizing surfaces that are heavily touched, such as cash registers or payment terminals. , doorknobs and tables.
Even if restaurants limit their capacity, however, the aerosolized virus can build up if ventilation is inadequate, Dr Allen said.
“It doesn’t matter if it’s a restaurant, a spin class, a gym, a choir practice – if you’re indoors without a mask, weak or no ventilation, we know that’s a higher risk.” , did he declare. “Respiratory aerosols accumulate inside. It is that simple. This is a real problem for restaurants. “
Linsey Marr, an aerosol transmission expert at Virginia Tech, said Americans couldn’t be expected to keep up with all of the latest science, and that many simply rely on what’s open or closed as an indicator of what’s sure.
But eating inside is particularly risky, she added. People typically sit in a restaurant for an hour or more and don’t wear masks when eating, making them vulnerable to airborne viruses.
“Limiting capacity will help reduce the risk of transmission, but eating indoors is always a high-risk activity until more people are vaccinated,” she said.
Restaurant owners are particularly exposed. Although they can wear masks, diners do not, which reduces protection against the virus. And workers spend many hours indoors every shift, Dr. Allen said.
He recommended that conservators wear a double mask, wearing a surgical mask covered with a fabric mask, or buy high-efficiency masks like the N95, usually reserved for healthcare workers, or the KN95 or KF94 masks. , taking steps to ensure that they are not counterfeit.
“Now is not the time to let our guard down and pull the controls when we are so close to getting a lot of people vaccinated,” Dr Allen said.
Eileen Sullivan contributed reporting.