Is eating inside a restaurant safe? Coronavirus experts explain the science

In an effort to curb Covid-19's lightning spread, many cafes, bars, and restaurants across the United States shuttered their doors in mid-March. Six months of empty dining rooms and missing profits have, in turn, put an estimated 97,966 U.S. restaurants out of business.

Faced with record losses, fluctuating case counts, and increasing pressure from consumers eager to dine in, the majority of states have reopened indoor dining as of September 14. New York, one of the states hardest hit by the novel coronavirus but now with a relatively low transmission rate, is set to resume indoor dining September 30.

Despite these reopenings, across the board, health experts say eating outside or, better yet, getting take out from your favorite spot are safer options than dining in. However, like all decisions during the pandemic, indoor dining lies on a spectrum of risk.

If you're considering your first sushi dinner indoors or craving a cozy pasta meal sheltered from the autumn chill, public health expert LaMar Hasbrouck advises people to ask two questions:

1) Is eating out an option?

2) Is it an option for me given my risk profile?

"These decisions must be personalized," Hasbrouck says. "Ultimately, if your risk profile outweighs the benefits of eating out, it might be a good idea to avoid eating out."

What the research says— To date, scientists don't know exactly how much eating out (or in) is contributing to Covid-19 transmission. They do know indoor dining presents an elevated risk of catching and spreading Covid-19, compared to eating outside or at home.

That's because when a person infected with Covid-19 breathes, coughs, sneezes, talks, or sings, they spray respiratory droplets into their immediate vicinity. Some of these potential coronavirus containing droplets fall immediately to the ground, end up on surfaces, or linger and then evaporate in the air. Others land on the eyes, noses, or mouths of others, or are inhaled.

"It is not just about distance ... "

As Denis Nash, an epidemiologist and executive director of the CUNY Institute for Implementation Science and Population Health, puts it, indoor dining is essentially the equivalent of being indoors without a mask —since people don't wear masks while eating or drinking. And we know that is something to be cautious of.

"We know from studies that transmission can occur in restaurants when one infected person is there eating," Nash tells Inverse.

"It can infect people several tables away if the airflow and HVAC system is not safe. It is not just about distance, but what droplets and aerosols are moving around through the air."

Air circulation is crucial: In indoor settings, especially with stagnant air, tiny viral droplets can stay suspended in the air for an estimated eight to 14 minutes. Outside, with constantly circulating air, droplets tend to evaporate much faster, typically within seconds.

Some data links restaurant and bar activity to alarming spikes in Covid-19 cases in states like Florida, Texas, and California. In Colorado and Louisiana, where contact tracing data is publicly available bars and restaurants are responsible for about 20 percent of cases traced to a known source. San Diego traced nearly one-third of community outbreaks to restaurants and bars, more than any other setting. In New York, state officials say about 10 percent of coronavirus clusters outside of New York City have been tied to bars and restaurants, a source of infection second only to large gatherings.

A study published on September 11 by the Centers for Disease Control and Prevention exemplifies these risks. Researchers traced the activities of 314 adults showing Covid-19 symptoms who were tested in 11 U.S. medical facilities in July, finding that people who tested positive for Covid-19 were more than twice as likely to have dined at a restaurant in the two weeks before getting sick than people who were uninfected. Those who tested positive and did not have close contact with anyone sick were also more likely to report going to a bar or coffee shop.

The team did not see the same effect in visits to salons, gyms and houses of worship, or in the use of public transportation.

Bars versus restaurants — Heading out for drinks rather than a sit-down meal may also present additional threats.

"It is unclear to know the relative contribution of bars and indoor dining," Hasbrouck says. "Both scenarios are potential super-spreader settings, but I would guess bars have a much higher risk."

Bars may be higher risk because they tend to facilitate the close interaction of strangers, Hasbrouck explains. Restaurants might bring close family and friends together who you are more likely to share a bubble with.

"Bars seem can be continuously occupied as people come and go," Hasbrouck adds. "The time people spend at bars vary, but can be far longer than the time it takes to have a meal."

Bars also have high-touch surfaces — a risk because the virus can live on these surfaces for days, Hasbrouck says. In restaurants, tables are typically cleaned or changed out after each party.

"Then again, take-out from your favorite restaurant is always an option."

In an interview with MSNBC, Dr. Anthony Fauci said bars and restaurants should stay closed until the spread of COVID-19 can be maintained in areas of the country seeing rising cases. "When you have restaurants, indoors, in a situation where you have a high degree of infection in the community, you’re not wearing masks, that’s a problem," Fauci explained.

"Bars are a really important place of spreading infection, there’s no doubt about that."

Even if diners may be safe indulging in the occasional indoor restaurant meal, servers, hosts, and restaurant staff members working for hours on end may not be.

"Patrons are going to be in and out, but wait staff, bus staff, bartenders, cooks and others will be at much higher risk," Nash says.

Indoor versus outdoor eating — When it comes to the food industry, each states has varying guidance. Some states are reopening at diminished diner capacity, installing new air filtration systems, and requiring staff members to wear PPE.

Just because local health authorities give indoor dining — or any activity— a green light, doesn't necessarily mean it's safe for you, experts say. Hasbrouck and Nash both suggest considering local health guidance, but not blindly deferring to it.

"When something is allowed by your local government, you then have to ask yourself if it makes sense to do it, given everything else that's important to you," Nash says.

"Some states and localities like New York use the best science as a guide and closely monitor the data as they relax restrictions," Hasbrouck says. "Others, like Georgia, not so much. In fact, they seem to prioritize restarting the economy above public health and public safety."

"There has been a lot of guidance coming from elected officials and their appointees who are not experts, who sometimes have conflicts of interest or who just don't care about the health consequences of their decisions," Nash adds.

The Inverse analysis — If you're thinking of dining in at a restaurant, Hasbrouck suggests doing a bit of research. Consider your personal health vulnerabilities, transmission rates in your community, who you are dining with, and the restaurant's diner capacity.

Scope out diner reviews and a restaurant's website to see their cleaning protocols, whether the staff is properly wearing masks and gloves, how the tables are spaced, and whether there is one-way traffic flow, Hasbrouck adds.

"The more serious they take the risk, the more confidence I would have," Hasbrouck says. "Then again, take-out from your favorite restaurant is always an option."

Nash puts it simply:

"I would say if you have any symptoms or if anyone in your party has symptoms, don't do it. If you or someone you see regularly is at high risk for a bad outcome of Covid-19, don't do it. If there is a possibility that if you became infected, that it would spread further outside of your household, then I would say don't do it."