Airplane passengers have been collecting tips and tools to protect themselves from the coronavirus for the better part of two years, but the super-transmissible omicron variant poses a renewed threat. Because it is adept at slipping past disease-fighting antibodies, even vaccinated travelers will need to deploy every defensive weapon at their disposal.

“It is more likely that the person sitting next to me is infected than it was a few weeks ago,” said Robert Wachter, chair of the department of medicine at the University of California at San Francisco. “If he or she is infected, they are more contagious.”

David Powell, medical adviser to the International Air Transport Association, told Bloomberg News that the risk of infection from omicron on planes is assumed to be two to three times greater than with delta – which is itself considered highly transmissible. He emphasized that getting vaccinated and boosted is “the greatest protection you can give yourself.”

So what else should travelers be doing? These tips from experts are more relevant than ever.

Wear a medical-grade mask

A federal mask mandate remains in place for airports, trains, planes and other forms of public transportation. But travelers need to make sure to wear the right kind of mask – or wear two – and use face coverings consistently.

Cloth masks should not be considered for flying; they aren’t even allowed on some airlines, especially in Europe. Lin Chen, director of the Travel Medicine Center at Mount Auburn Hospital in Cambridge, Massachusetts, and an associate professor at Harvard Medical School, said N95 masks are the best but not the most comfortable. She said KN95s are “quite good” also. For those who want to use a surgical mask, adding a cloth mask on top can help reduce any gaps.

“I think (cloth masks) are probably not as helpful with omicron,” Chen said, though she added that “any layer is going to be better than none.”

She said she has too often seen people wearing their masks below their nose or around their chin, which she called “so unfortunate.” Chen said wearing a mask properly is “one of the best ways” for people to limit spreading the coronavirus and protecting themselves “whether they’re vaccinated or not.”

Eat and drink carefully – if at all

Experts say that for a short flight, it is best to keep a mask in place the entire time. But, Chen said, it is also important that travelers avoid dehydration, especially on longer flights.

Wachter, who started flying again about a year ago, said he would be a little more anxious on a plane now than he was three weeks ago. That includes removing his mask to eat or drink.

“During that time everybody’s got their mask off eating or drinking, it’s a little safer than the average restaurant because of the air exchange, but not that much,” he said.

In a list of holiday travel tips, the Association of Flight Attendants-CWA said fliers should lower their mask only briefly to take a sip or bite, then replace it over their nose and mouth – not keep the mask off during an entire meal.

Wachter said that if he did take his mask off, he would wait for a time when other passengers were masked, then remove his face covering for just a couple minutes to “wolf down food or drink.”

Grab a window seat, then crank up the air

Vicki Hertzberg, director of Emory Nursing’s Center for Data Science, told The Washington Post before the pandemic that passengers in the aisle are at a higher risk of infection than those sitting in a window seat because they have more exposure to people passing by.

“So the strategy I take now for flying is, I take a window seat, and I don’t get up,” she said in February 2020.

Wachter said that if people can afford it, a seat in business class is a safer option than the more crowded part of the plane. She said she also turns the air blower on “as hard as it will go” to keep as much air moving as possible.

Avoid crowds from check-in to boarding

Powell, the air transport group adviser, told Bloomberg News that ventilation is not as robust in airports as it is on planes. There is also much more potential for face-to-face contact with strangers when you consider interactions moving through the check-in counter, security lines, common areas and shops.

Experts say travelers should keep as much distance as possible at every turn, starting by carrying bags on board or choosing a contact-free way to check them. If it isn’t possible to eat and drink before getting to the airport, fliers should try to find a remote place.

“If you have to eat and drop your mask, try to find a place where you have to be as distanced from people as possible,” Thomas Russo, the infectious-disease chief at the University at Buffalo, told The Post in February.

Passengers should also avoid clusters at the gate when it is time to board.

“This is the moment where [you should] let the crowd go first. Let everybody get on there and wait,” Russo said. “Even though masks significantly mitigate risk, they’re imperfect. . . . Avoid any situation where you’re in close quarters with people.”

For those who do have to check a bag, they should wait until crowds ease at baggage claim and keep a mask on the entire time.

Know there is risk for everyone

Chen, a former president of the International Society of Travel Medicine, said unvaccinated people should avoid travel so they can minimize their own exposure and the risk of spreading the virus. She said those who are immunocompromised or otherwise at high risk of severe disease – even if vaccinated and boosted – should also avoid travel for now.

“I think if you’re perfectly healthy, fully vaccinated and boosted and willing to take some risk … I wouldn’t tell them not to,” she said.

Wachter said he does recommend putting off travel overseas for now – and has told a family member to cancel a trip to England.

“If you get sick in a foreign country, it is a major bureaucratic hassle to get back,” he said.

But, he said, he would still take a domestic trip to see friends or family for the holidays – albeit cautiously.

“I can’t guarantee that next Christmas is going to be better than this one,” he said.