For travel expert Rick Steves, the gradual return to post-pandemic normalcy means an even slower return for his business bussing tourists around Europe. While he expressed confidence that millions of Americans will get their opportunity to travel this summer, he said Tuesday on Boston Public Radio that he expects his tours may have to hold off a little while longer.

“We took 30,000 people on 1,500 tours in 2019,” he explained, underscoring the risk for virus transmission among tourists and the communities they interact with. Predicting a return to business as (mostly) usual by late 2021or early 2022, he said they're not looking to ramp things up until vaccination "is really solid across the board.”

The TV and radio host went on to reflect on the sigificance of ensuring that the international community has just as much access to COVID-19 vaccines as here in the U.S.

Read More: More U.S. Travelers Are Flying Again Despite COVID-19 Risks

"It can’t be just us" he said, of the race to reach herd immunity. "That’s the interesting thing about fighting this virus … for one nation to be truly safe, all nations, I think, need to be immune."

According to the latest CDC data, 21% of Americans have received at least one dose of a COVID-19 vaccine. By contrast, in the European Union, which has been slower to approve vaccines, less than 7% of citizens have recieved a shot.

“It really is just a matter of patience; it is going to happen,” Steves said.

Read More: Why You'll Likely Need A 'Vaccine Passport' To Travel In The Near Future

When international travel does return, it’s expected that many services will require a form of vaccine "passport" for tourists to prove they aren’t COVID-19 carriers, something Steves emphatically called “not a big deal.”

"When I was younger and I was traveling, we routinely traveled with a yellow international certificate of vaccination in our passport,” he said. “They don’t want to let you in their country unless they know you're vaccinated. And as travelers, we should remember that when we have these standards that we have to meet to travel, it’s not to protect us — it’s to protect the people in the country that we’re visiting.”

Rick Steves is an author, television and radio host and the owner of the Rick Steves' Europe tour group. You can catch his television show, "Rick Steves’ Europe," weeknights at 7:30 p.m. on GBH 2 and his radio show, “Travel With Rick Steves,” Sundays at 4 p.m. on GBH.