This story has been edited to clarify vaccine effectiveness.

With America’s vaccine rollout progressing at breakneck speeds, we have watched the number of travelers rise rapidly.

The Centers for Disease Control and Prevention announced that fully vaccinated people may travel safely, and many health experts say they feel safe traveling again. But although airlines are bringing back food and drink services, experts still warn against eating and drinking on planes.

Robert M. Wachter, chair of the department of medicine at the University of California at San Francisco and guest host of the podcast “In the Bubble,” says when passengers are allowed to take their masks off for meal services, his comfort with air travel goes away.

“When [planes] turn into a flying restaurant, the dynamics of spread become very different,” Wachter says. “I would not eat at an indoor restaurant at this point, even being fully vaccinated, and so the time during which the plane is, in fact, an indoor restaurant is a time when it is somewhat less safe.”

A recent study released by the CDC supports Wachter’s concerns. Being on packed planes with maskless passengers does increase your risk of coronavirus exposure, despite the plane’s ventilation system.

“The crowding on the plane is going to be an issue,” says Tom Kenyon, Project HOPE’s chief health officer who spent 21 years at the CDC. “We know that the closer you are to someone with an infectious disease that’s respiratory transmitted, the more likely you are to get infected. It’s not transmitted through the ventilation system; it’s transmitted through direct contact.”

Proof of vaccination to travel or attend school is not new, but the coronavirus has introduced a potential need to modernize outdated paper standards. (Jonathan Baran/The Washington Post)

Travelers may wonder why there’s still risk at all if they have been immunized. Wachter explains that it’s because vaccine protection is great but not an impenetrable shield.

“Being fully vaccinated means that I’m highly protected against getting covid, but not 100 percent,” he says.

Pfizer and Moderna, both two dose vaccines, are 95 percent effective while J&J is 72 percent effective after one dose. (You can get all your vaccine questions answered here.)

Kenyon’s advice for vaccinated fliers is to be vigilant about wearing your mask (potentially an N95), use disinfectant on your hands after touching surfaces and consider wearing a face shield as the coronavirus can be transmitted through the surface of the eye.

“At some point, you have to take off your mask to take a drink or have a meal, especially on a long flight — which can put you at risk because everybody does it at once. So I think a face shield would be in order.”

Wachter agrees that there is good evidence that some level of eye protection is helpful. In addition to double-masking on a flight, he opted for glasses over a face shield. And while he recognizes there is risk while eating and drinking on a plane, he is also human. When Wachter needed some water or food, he waited to do so until after the flight’s meal service.

“I waited a period of time until it looked like everybody had their masks back on before I very quickly gobbled down some food and chugged a bottle of water, in I’d say about 30 seconds, and quickly put the mask back on,” he says.

Wachter added: “Despite the fact that I’m fully vaccinated, I still think that you cannot say [flying] is a zero risk thing to do, but I think it’s an exceptionally low risk thing to do. And it’s an even lower risk if you take those kinds of precautions.”

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