The Centers for Disease Control and Prevention removed every country in the world from its “do not travel” recommendation as it applied updated parameters Monday to its multi-tiered Travel Health Notices system.

The change, which the CDC said last week would take effect Monday, was intended to significantly reduce the number of countries listed under the highest level of its alert system. Before Monday, the agency listed countries at “Level 4” with a recommendation to avoid travel when they hit certain COVID-19 metrics.

With virtually half the world, including most of Europe, listed at Level 4, though, the CDC has now shifted to reserving that highest alert level for only the most severe situations or “special circumstances.”

No countries met that criteria Monday, but Level 3 (“high” levels of COVID-19) had far more countries listed than any other level, including all of North America and nearly every country in Europe.

This marks just the latest change in how the CDC communicates concerns about the virus when it comes to international travel. These changes are not likely to have any substantive impact on your existing travel plans, but understanding the CDC’s system could help you get a better sense of the COVID-19 situation in another country as you prepare to travel.

How the system works

The CDC’s travel health alert system has evolved over the course of the pandemic, particularly as international travel became more of an option.

While the CDC has typically used a three-level alert system for health advisories dating back to before the pandemic, the agency went to four levels in November 2020 as a way to align more closely with the alert systems used by public health organizations.

The agency monitors numerous factors in determining how to rank a country on its alert system, but the No. 1 factor is the number of cases per 100,000 people in the last 28 days. Before Monday, countries’ metrics could land them on one of four Travel Health Notice levels, including Level 1: Low; Level 2: Moderate; Level 3: High; and Level 4: Very High.

Relying on data from the World Health Organization, the CDC updates its advisories each Monday.

Starting this week, though, the agency is, by and large, funneling countries into Levels 1, 2 or 3, with Level 4 now denoted “Do Not Travel/Special Circumstances.”

In announcing the pending changes last week, the CDC said it would reserve those circumstances that could include “rapidly escalating case trajectory or extremely high case counts, emergence of a new variant of concern, or healthcare infrastructure collapse.”

Why this change? The CDC says the goal is “to help the public understand when the highest level of concern is most urgent.”

To give you a sense of how the new methodology changed the warnings, take a look at what the CDC’s alert map looked like prior to Monday. Countries in red fell under the previous Level 4 which, as you can see, meant the agency was urging people not to travel to virtually anywhere in Europe, among other places like Australia and Iceland. This, despite international travel continuing to open up further. Again, the map below is now outdated.

Now, take a look (below) at the CDC’s new map as of Monday. You can see that while much of the world (including the U.S.) is highlighted in orange, indicating “high” levels of COVID-19, no countries are in red under the new system.

Bottom line

These changes come just as the new White House COVID-19 response coordinator has said that when it comes to evaluating the COVID-19 situation as a whole, above cases, hospitalizations will be the most important metric to track.

With the CDC’s newest changes, you know that if, in the future, you see a country listed at Level 4 on its Travel Health Notices, that country is truly dealing with a precarious COVID-19 situation.

The CDC’s new alerts come out each Monday, so TPG will continue to monitor how countries fluctuate each week.