Traveling has always come with complications, but the coronavirus pandemic has made it more challenging than ever. Our By The Way Concierge column will take your travel dilemmas to the experts to help you navigate the new normal. Want to see your question answered? Submit it here.

We are traveling to Iceland this month. I noticed that it has been raised to a Level 4. The vaccination rate in Iceland is 86 percent, and with the new outbreak, 90 percent of cases are asymptomatic. We will be with a small National Geographic group. Both of us are fully vaccinated. Do you have any advice for us? — Anonymous

Travel advisories made a big splash back in March 2020 when the State Department instituted a blanket warning against going essentially anywhere due to what we called “the worsening global spread of the novel coronavirus.” Five months later, the worldwide advisory was lifted, and the agency went back to issuing warnings by country.

With the scourge of the delta variant, travel advisories have become more severe again, as you saw with Iceland.

It’s a confusing turnaround from the optimistic beginning of the summer: We had the vaccine. Countries across the European Union began welcoming vaccinated Americans back. Mexico saw record-breaking visits.

But alas, rapidly rising case numbers changed that outlook. Now popular destinations such as France, Jamaica and Greece — despite being open for visitors — have “Level 4: Very High” travel notices from the Centers for Disease Control and Prevention.

What does that mean for your group Iceland trip, which you presumably booked when things were on the upswing? I called the CDC to ask.

Cindy Friedman, head of the CDC traveler’s health branch, explained that their travel health notices are “based on the number of covid cases per population at a destination over a 28-day period, which is two incubation periods,” she said.

To determine a country’s risk level in its four-tiered system, the CDC pulls data from sources such as the World Health Organization and keeps in constant communication with local health authorities. They then use an algorithm to determine a country’s overall risk level.

“For very high Level 4 countries, you should avoid travel to these destinations, whether you’re vaccinated or not,” Friedman said.

That being said, Friedman acknowledged there are going to be regional differences in a country’s covid-19 situation. For example, the Level 4 warning for the United States reflects the status of the entire nation. We know that a backpacking trip through Montana comes with completely different risks than a club-hopping weekend in Miami.

“Obviously, we can’t make the travel notice about every part of the country and every activity,” Friedman said. “But our advice for any Level 4 country is to avoid travel.”

Additionally, the stakes are different for vaccinated travelers than they are for the unvaccinated. As the State Department advisory for Iceland reads, “Your risk of contracting COVID-19 and developing severe symptoms may be lower if you are fully vaccinated with an FDA authorized vaccine,” referring to the Food and Drug Administration.

(By the way, the CDC travel health notices are not the same as the better-known State Department Travel Advisories. However, the health risks you read about in a State Department travel advisory are based on CDC intel. For more information on CDC versus State Department advisories, read this story from my colleague Hannah Sampson.)

Adrian Hyzler, chief medical officer at Healix International, which specializes in international security, says advisories and notices shouldn’t be your end-all resource for making travel decisions.

“To have countries on a level for high risk in a similar situation to countries where there is really uncontrolled transmission doesn’t really make sense at all,” he said.

Hyzler argues in some Level 4 places, such as Iceland, France or his home, Britain, “life seems to go on as normal now,” he said. “Public transport is back to 100 percent levels. It’s a situation where you have a number of cases, and you happily live with them.”

Friedman also doesn’t think the CDC or State Department advisories are the only sources travelers should reference. She recommends looking at specific country warnings from both agencies, as well as a destination’s government health ministry or tourism board website for more information on pandemic restrictions and travel requirements as you consider your travel plans.

There are also travel apps that can help you keep tabs on pandemic concerns, such as TripIt. Once you plug in your itinerary, TripIt provides a link to a “COVID-19 Summary” showing coronavirus restrictions, guidelines, infection and vaccination rates, as well as vaccination requirements, among other details for the place you’re going to visit.

Ultimately, it’s up to you to decide how to process advisories and health notices. What’s your personal risk tolerance?

“If the person has a medical condition that puts them at a higher risk for covid, they should talk to their physician about [travel] and see if it’s really worth taking the risk,” Friedman said.

Before you even get to checking the travel advisories or talking to your doctor, health experts’ No. 1 piece of advice: Get vaccinated.

“You shouldn’t be traveling internationally until you’re fully vaccinated,” Friedman said, explaining that advice is for both your safety and that of locals in the place you’re visiting.

“Right now, the United States is a Level 4 country, very high,” Friedman said. “It’s important to be a global citizen and make sure that you don’t put others at risk for unnecessary travel.”

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