An already powerful pent-up desire to travel has only intensified with global weariness of pandemic restrictions and the rollout of vaccines in some countries.And the summer travel season is fast approaching in the Northern Hemisphere.People are asking from different corners of the globe: "Can I travel -- and should I?" The answers are never universal.In the United States, many people -- as seen in the crowds of spring break revelers in Florida and the latest passenger tallies at airport security checkpoints -- are already on the move, whether they're vaccinated or not."Fully vaccinated travelers are less likely to get and spread COVID-19," according to long-awaited guidance released on April 2 from the U.S. Centers for Disease Control and Prevention. The agency outlines precautions for vaccinated travelers for both domestic and international trips.The CDC still recommends against nonessential travel overall, CDC Director Dr. Rochelle Walensky said as the new guidelines were released."We haven't changed our guidance for nonessential travel at all. We are not recommending travel at this time, especially for unvaccinated people," Walensky saidIn Sweden, which skipped lockdown measures imposed by its Scandinavian neighbors and suffered a higher death toll, the Public Health Agency's website emphasizes "great personal responsibility" for travelers to follow local guidance and prevent the spread of infection.In the United Kingdom, most travel -- domestic or international -- is currently prohibited by the government, although some domestic travel is likely to be permitted by mid-April. The United States clearly has far fewer restrictions on movement.When and how far you can travel -- and whether the choice is yours -- depends on where you live and, in many cases, on your own risk tolerance.Should I travel?There's a low risk of getting or transmitting coronavirus in transit, especially when people are traveling by private vehicle, said CNN Medical Analyst Dr. Leana Wen, an emergency physician and visiting professor at George Washington University Milken Institute School of Public Health.Air travel, particularly when everyone is masked, is also quite safe, she said.Wen was critical of the CDC's "overly cautious" delay in issuing travel guidance for vaccinated Americans. That guidance has now been released, with additional caution urged for international travel.Even those who haven't been vaccinated can travel in a relatively safe manner, Wen said, if they're going with the objective of seeing one other family."That's low risk, and there are ways for unvaccinated people to still do that safely. For example, they can quarantine and get tested prior to the trip," she said.Tony Johnston, coming at the "should I travel" question from Ireland from a tourism rather than a medical perspective, has a definitive answer in the other direction.We should not travel yet, he says."People need to remain cautious and conservative for another few months. The great prize, if people are patient, is that the international tourism industry will reopen sooner rather than later," said Johnston, who is head of the department of hospitality, tourism and leisure studies at Athlone Institute of Technology.Another wave of the virus could jeopardize that reopening, he said. Politicians in Ireland are calling for a very cautious reopening, given the skyrocketing number of hospitalizations and deaths in the country after Christmas.It's what happens when you get there that's keyFor those who plan to travel, what you do when you get to your destination is often a bigger concern than what happens in transit, said Dr. William Schaffner, an infectious diseases specialist at Vanderbilt University Medical Center in Nashville, Tennessee."The most careful way to travel is by car because you can create a cocoon of protection, you can run in and out of restrooms, you can get drive-through food, you can take wipes with you when you wipe off the gas pump when you're refilling the tank."But once again, it's what you do wherever you're going that increases your risk."Spring breakers in Florida are gathering at the beach outside, but then they go to bars and restaurants "and that's when they have a drink or three and the masks come off, and they speak with enthusiasm and they're close to other people in enclosed spaces for prolonged periods of time," Schaffner said.While the CDC is urging unvaccinated travelers to stay home, the agency has outlined key considerations and safety measures for those who feel they must travel. It also looks at various aspects of travel -- from transportation to food and lodging -- and ranks approaches to each from safest to least safe.Travelers who plan to engage in higher risk activities should ideally wait until they're vaccinated, Wen said, "and even then try to pick and choose your activities because you don't want to do everything that's high risk all together."Caution is essential -- for unvaccinated and vaccinated travelersRemember that vaccinations are not a "suit of armor," Schaffner says. It's still important to wear masks and maintain social distance as much as possible.Schaffner and his wife were recently talking with three other couples they know, all of whom have been fully vaccinated and have upcoming travel plans.His wife recently drove down to Florida with a friend who has been very careful and got tested in advance to attend to some business at their house there."They were absolutely meticulous" about safety, he said. They ate most of their meals at home with the exception of one late lunch in "a completely outdoors location where there were essentially no other people around."If you are unvaccinated and engaging in higher-risk behaviors while you're away, you should quarantine and then get tested once you get home, Wen said.The best advice for anyone who intends to travel soon?First off, "please do everything you can to get vaccinated. Number 2, if you can't get vaccinated, get tested before you go to make sure that you're negative. And Number 3, where are you going and what do you intend to do? Please be as careful as possible," Schaffner says.He has a colleague who signs off of every phone call with, "Stay out of the bars!"Good advice, he says.