Island of Tjorn, Bohuslan, on West Coast of Sweden.

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The US Centers for Disease Control and Prevention has added two destinations to its “high” category for Covid-19 risk – including a Caribbean nation popular for its beaches.

Representing three continents, the three destinations added to the list on Tuesday are:

• Colombia
• Iraq
• Kosovo
• North Macedonia
• Paraguay

The CDC overhauled its ratings system for assessing Covid-19 risk for travelers in April.

Level 3, or “high,” is now the top rung in terms of risk level and applies to places that have had more than 100 cases per 100,000 residents in the past 28 days. Level 2 and Level 1 are considered “moderate” and “low” risk, respectively.

All three new entries to Level 3 on Tuesday had previously been at Level 2.

Sweden, renowned for its culture and natural beauty, is one of just a few European nations to even make it out of the ‘high” risk list since the ratings overhaul. Along with Romania, it moved into the “moderate” risk list on June 21. This week, Romania remains at Level 2.

There were about 115 destinations at Level 3 on July 18. Level 3 locations account for almost half of the roughly 235 places monitored by the CDC.

Level 4, previously the highest risk category, is now reserved only for special circumstances, such as extremely high case counts, emergence of a new variant of concern or health care infrastructure collapse. Under the new system, no destinations have been placed at Level 4 so far.

There were almost 115 destinations at Level 3 on June 27. Level 3 locations account for almost half of the roughly 235 places monitored by the CDC.

More on Level 3

The village of Oia on Santorini island is a favorite tourist spot in Greece, which remains at the CDC's Level 3.

Much of Europe has been stubbornly lodged at Level 3 for months with the summer travel season in full swing. As of June 27, the following popular European destinations were among those remaining at Level 3:

• France
• Germany
• Greece
• Ireland
• Italy
• The Netherlands
• Norway
• Portugal
• Spain
• United Kingdom

Those aren’t the only high-profile spots that find themselves at Level 3. Numerous other destinations around the world are among those in the “high” risk category, including the following:

• Brazil
• Canada
• Costa Rica
• Malaysia
• Mexico
• South Korea
• Thailand
• Turkey

The CDC advises that you get up to date with your Covid-19 vaccines before traveling to a Level 3 destination. Being “up to date” means you have had not only the full initial vaccinations but any boosters for which you’re eligible.

Level 2

Baalbek is a UNESCO World Heritage Site in Lebanon, which has moved up to the CDC's "moderate" risk category.

Destinations carrying the “Level 2: Covid-19 Moderate” designation reported 50 to 100 Covid-19 cases per 100,000 residents in the past 28 days. The CDC moved four places to this level on Monday:

• Colombia
• Iraq
• Russia
• Saudi Arabia

The move was not good news for the Middle East’s Jordan and Lebanon, which had been at Level 1. For North Macedonia in Europe’s Balkans, the move was in a positive direction, having previously been at Level 3.

There are a total of 21 places in the “moderate” risk category this week.

You can view the CDC’s risk levels for any global destination on the agency’s travel recommendations page.

In its broader travel guidance, the CDC has recommended avoiding all international travel until you are fully vaccinated.

Level 1

To be listed as “Level 1: Covid-19 Low,” a destination must have had 49 or fewer new cases per 100,000 residents over the past 28 days. No new destinations were added to the category on June 27.

• Saba
• Saint Pierre and Miquelon

Saba, in the Caribbean, had been at Level 2. Saint Pierre and Miquelon, a French archipelago south of Newfoundland, Canada, had been at Level 3.

A few of the more popular places in the “low” risk category this week include Indonesia, India and the Philippines.

Unknown

The Hungarian Parliament is seen through the arches of Fisherman's Bastion in Budapest. The CDC warns against travel to places where the Covid-19 risk is "unknown."

Finally, there are the destinations the CDC has deemed to be of “unknown” risk because of a lack of information. Usually, but not always, these are small, remote places or places with ongoing warfare or unrest.

• Armenia
• Laos
• Liberia
• Mongolia

Haiti, Iran and Mozambique had all been at Level 1 last week. Hungary, a favorite stop on the Eastern European travel circuit, had been at Level 3.

The CDC advises against travel to these places precisely because the risks are unknown. Other destinations in this category that typically draw more tourist attention include French Polynesia, Macau and the Maldives.

A medical expert weighs in on risk levels

Transmission rates are just “one guidepost” for travelers’ personal risk calculations, according to CNN Medical Analyst Dr. Leana Wen.

We’re in “a phase in the pandemic where people need to make their own decisions based on their medical circumstances as well as their risk tolerance when it comes to contracting Covid-19,” according to CNN Medical Analyst Dr. Leana Wen.

There are other factors to weigh in addition to transmission rates, according to Wen.

“Another is what precautions are required and followed in the place that you’re going and then the third is what are you planning to do once you’re there,” she said.

“Are you planning to visit a lot of attractions and go to indoor bars? That’s very different from you’re going somewhere where you’re planning to lie on the beach all day and not interact with anyone else. That’s very different. Those are very different levels of risk.”

Vaccination is the most significant safety factor for travel, since unvaccinated travelers are more likely to become ill and transmit Covid-19 to others, Wen said.

And it’s also important to consider what you would do if you end up testing positive away from home.

While US-bound travelers no longer have to present a negative Covid-19 test to get home from international destinations, the CDC still advises testing before boarding flights back to the States and not traveling if you are sick.

“Of course, if people have symptoms or exposure while traveling, they need to get tested, and if they test positive, to follow CDC’s isolation guidelines,” Wen told CNN Travel.

If you’re concerned about a travel-specific health situation not related to Covid-19, check here.

Top image: The island of Tjorn off the west coast of Sweden. (Peter Adams/Stone RF/Getty Images)