Omicron Is Here. Should You Cancel Your Trip?

To cancel or not to cancel. That is the question that travelers are grappling with as the Omicron variant scuttles around the world, reminding people that the pandemic roller-coaster ride is far from over. What’s different this time around is that the holiday travel season is right around the corner, and tourism, in general, has finally started to rebound.

Whether the variant, which has been identified in at least 20 countries, is more severe or more transmissible than other forms of the coronavirus will likely remain unknown for at least two weeks. The United States is among the countries that believe that it is a serious enough threat to merit new rules. Soon after researchers in South Africa discovered it, President Biden suspended incoming U.S. travel from eight African nations. On Tuesday, the Centers for Disease Control and Prevention said that the United States would tighten testing requirements, requiring all travelers entering the United States — including returning Americans — to provide negative tests taken within one day of departure instead of the three days now permitted for vaccinated travelers.

Though most people are by now experienced with making high-stakes health-risk assessments in the face of incomplete information, that doesn’t make the decision about whether to travel or not easy.

Courtney Niebrzydowsk, an international travel risk analyst at the University of Denver, said she urges people to ask themselves two primary questions when they consider traveling: 1. Can this travel be postponed? and 2. How flexible can you be?

She also urges people to think through all the scenarios that could emerge if they travel — like testing positive, facing a canceled return flight or learning last minute that their destination country has expanded its quarantine requirement — and map out detailed contingency plans, including costs, missed obligations and how to approach health care. Often, she said, after going through this exercise, people have “less appetite for travel.”

The C.D.C. advises against international travel until a person is fully vaccinated. The World Health Organization recommends that people who are not fully vaccinated, have not previously been infected, are 60 years or older or have comorbidities such as heart disease, cancer and diabetes should postpone travel to areas with community transmission.

Jessica Herzstein, a physician who advises organizations on how to manage the coronavirus and other health risks, including those associated with travel, said that she discourages anyone who is unvaccinated or immune-compromised from traveling. She also advises travelers going to destinations with a particularly high prevalence of cases to consider canceling. For those planning to travel, Dr. Herzstein strongly advises booster shots for those eligible and to take along a supply of at-home rapid antigen tests.

David Freedman, the president-elect of the American Society of Tropical Medicine and Hygiene, said that the type of mask one wears while traveling is particularly important. Dr. Freedman discourages people from wearing cloth or homemade masks; N95 or KN95 masks are preferable, he said.

It is difficult to assess how likely it is that a traveler will encounter an infected individual while flying to their destination. This is a particularly important to consider when traveling with children too young to be vaccinated or to wear a mask. Domestic flights in the United States do not require testing or proof of vaccination. Some countries and airlines require both. Others don’t.

Creating a shorter window for testing — as the United States recently did for everyone flying into the country from abroad, regardless of nationality — makes sense, Dr. Freedman said. Testing three days before a flight can miss those who are incubating the virus and could be contagious and test positive by the time they board their plane. He said that a flight with a P.C.R. test requirement is also lower risk than a flight requiring an antigen test. But, he added, there is potentially more risk of transmission in airports than on planes, with their advanced air filtration systems. So much is out of even a meticulous planner’s control.

Part of the challenge that many people are struggling with is how to weigh the other variables — like the mental health benefits of celebrating Christmas with family, or the professional benefits that might come from interacting with co-workers face-to-face. It’s easier for governmentsto define “essential travel” than for individuals, said Ms. Niebrzydowsk, the travel risk analyst.

Tatiana Torres, 37, who lives in Orange County, Calif., is among those struggling with this equation. Ms. Torres, a retail facilities coordinator for a company based in Canada, is supposed to travel there for a work holiday party next week. Because she started in January, she’s never been in the same room as her colleagues. Finally meeting them feels valuable, but she’s concerned that she might end up stuck in Canada, far from her sick cat.

“I’m just like, is it worth it for something so frivolous?” she said on Tuesday. She has yet to decide whether to cancel or not.

The fear of getting stuck is not unreasonable, said the travel risk experts. If a person tests positive, they will not be able to re-enter most countries, including the United States, until they test negative. Throughout the pandemic, many airlines have canceled flights at critical junctures, leaving people stranded for days — or even months.

One data point that determined travelers may want to consider, however, is that few nations have ever prohibited their own citizens from returning altogether.

“It’s pretty unheard of for a country to refuse to let one of their own citizens back in,” Dr. Freedman said. Throughout the pandemic, there have only been a few cases of this. (At one point China closed its land border with Russia to everyone, including Chinese citizens. Australia briefly prohibited its own citizens from returning from India.)

Still, when it comes to his own travel plans, he’s minimizing the risks by flying to Montreal. For the moment, the United States does not require a Covid test to enter via its land border with Canada. If he or a family member were to test positive, they would drive home.

Ceylan Yeginsu contributed reporting from Geneva.

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