Erika Richter, vice president of communications at the American Society of Travel Advisors, a trade group, said that travel was continuing to increase as more countries dropped restrictions. In the United States, travel is approaching prepandemic levels, according to Transportation Security Administration checkpoint metrics.

“We have seen since the beginning of the pandemic that travelers who wanted to travel would go through the hoops; they would do what was necessary to travel and to do that trip,” Ms. Richter said. “As more countries lift their restrictions, more people who may have been on the fence and may not have been in that ‘I’ll do whatever it takes’ category are now in the ‘Let’s go’ category.”

Travel restrictions proliferated at the start of the pandemic, as nations tried to keep the coronavirus and its variants at bay. But many were, in the end, no match for the virus’s ability to spread and mutate.

“Travel restrictions make sense when there is a big difference between prevalence and risk when you’re going between points A and B,” William Hanage, an epidemiologist at the Harvard T.H. Chan School of Public Health, told The New York Times last month, when the United States dropped its testing requirement for incoming air travelers. “If there isn’t a big difference, then they are not particularly valuable,” he said.