Help! If There’s a Chance That I Could Endanger Others, Should I Still Travel?

Dear Tripped Up,

My husband and I are both fully vaccinated, and the Centers for Disease Control and Prevention says that we’re good to travel — with some modifications, of course.

But I am faced with a dilemma. Alaska, where we live, has been on the forefront of vaccinations. But until everyone we might encounter on a trip has been vaccinated, I am struggling with the idea of getting on a plane unless it’s absolutely necessary. On the other hand, I realize that tourism-reliant destinations badly need help right now.

How can I think reasonably about the following questions: Can I travel — and should I travel — if I know there’s some chance, however small, that it could endanger others? And if I do travel, how can I ensure I’m keeping other people as safe as possible? Jackie

Dear Jackie,

With the news that vaccinated Americans may be able to travel to Europe this summer, the question of “We can, but should we?” is certain to be top of mind. And the decision fatigue is real, especially when you’re trying to weigh the public health and ethical elements of traveling.

“When the C.D.C. came out and said it’s OK to travel, that was based on a thoughtful review of the risk levels,” said Amber D’Souza, an epidemiology professor at the Johns Hopkins Bloomberg School of Public Health. “But the answer is not for everyone to hop on a plane; it is purely that people who are vaccinated can now consider whether to go on a plane in a way that they did not consider it before.”

Although private jets, hotel buyouts and vacation rentals offer the promise of hermetically sealed trips devoid of germs and strangers, most of us will encounter other people on vacation. And many of those people will be unvaccinated: There’s not a single state that has fully vaccinated a majority of its population yet, and there are plenty of countries around the world, from Spain to India, where infection rates are rising.

Vaccinated people are unlikely to become sick with Covid-19, but there is still a small chance they can become infected with the virus and potentially spread it to others. New data suggests these so-called “breakthrough infections” are rare, and that when vaccinated individuals do become infected, they are usually asymptomatic.

The likelihood of a vaccinated person becoming infected generally depends on two things, Dr. D’Souza said: “Whether you come in contact with an infected person, which is influenced by the infection rate wherever you are, and your own personal behavior in terms of distancing, masking and how many people you interact with.”

“Rates are rising right now in parts of the country,” she added, “and so when you’re vaccinated, your risk is lower, but it is not zero.”

So if a restaurant server, hotel clerk or airplane seatmate might be at risk or unvaccinated, what would ethics and public health experts say about the idea of you traveling?

Pamela Hieronymi, a philosophy professor at the University of California, Los Angeles, who researches moral responsibility and free will, pointed to the ethical theory of “contractualism” as a good framework.

“We know we all have to find a way to get along, and that we all have to constrain our pursuits in light of other people,” she said. “So contractualism asks: ‘What rules would we all agree to if each person gets a symmetric say?’”

Short of a pie-in-the-sky idyll where large-scale injustices are corrected by a much larger entity, like a government — setting aside certain flights exclusively for high-risk passengers, for example — the question becomes: What can you as an individual do?

“Here I think we can just think about the most vulnerable person and ask: Would they have a reasonable objection to you doing what we’re doing?” Dr. Hieronymi said.

As a vaccinated person, your perspective and risk is likely to be different than the perspective and risk of an unvaccinated person. Crowded airport-security lines, for example, may not be worrisome to you, but many others will feel differently, especially if they’re unvaccinated. The awareness that the people around you could be vulnerable can help guide your actions.

“Try to maintain spacing so that everyone is comfortable and risk is reduced,” Dr. D’Souza said. “Being physically proximate with others transmits this infection at the highest rates, so that’s what we need to be aware of: How many people we’re close to, especially inside.”

Avoiding crowds, as well as other established pandemic practices like wearing a mask inside and staying outside as much as possible where the risk of infection is much lower, straddles ethics and public health.

“The best way for us to treat one another in these circumstances is to comply with the directives that we’re getting from the people who are trying to solve the collective problem,” Dr. Hieronymi said. “No matter what we do, we are always putting one another at risk, so we need a way to do that respectfully, and collectively we need some way of cooperating and living together.”

Infection rates, which indicate the risk of exposure in a given place, can be helpful in determining where to go. But so can other elements of trip-planning: Even if infection rates are high in Florida, for example, your exposure level will be different if you’re sitting on an empty beach than if you’re partying, spring-break style, in crowded bars and restaurants.

“We do have a wonderful vaccine that reduces risk, and it is perfectly appropriate to consider having a vacation,” Dr. D’Souza said. “You are not introducing high risk to yourself or to others as long as you behave.”

Sarah Firshein is a Brooklyn-based writer. If you need advice about a best-laid travel plan that went awry, send an email to [email protected].