KYOTO, JAPAN - OCTOBER 14: People pass next to Hokan-ji Temple (also known as Yasaka Pagoda) on October 14, 2021 in Kyoto, Japan. Amid an almost complete drop in foreign tourism revenue and issues including an ageing population, a debt-laden subway system and an inability to collect property taxes from the city's numerous shrines, Japan's ancient capital has accumulated debts of over 7.5 billion USD and is set to face a 2.3 billion USD billion deficit by 2025. Kyoto's mayor has announced a plan to save around 1.5 billion USD over the next four years which, it is hoped, will be enough to prevent the central government from taking control of the city's finances. (Photo by Carl Court/Getty Images)

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CNN  — 

The US Centers for Disease Control and Prevention added even more destinations on Monday to its ever-growing list of places considered to be a “very high” travel risk for Covid-19.

Level 4, the CDC’s highest, has now swelled to almost 135 places, illustrating the rapid surge of the Omicron variant around the world. In early January, there were around 80 destinations listed there. Level 4 now has more destinations than all the other CDC categories combined.

Joining the Level 4 ranks this week are two island nations on opposite sides of the world: Japan in Asia and Cuba, the largest and most populous island in the Caribbean.

The other new Level 4 nations are also scattered around various parts of the globe.

Armenia is in the mountainous Caucasus region on the far reaches of eastern Europe. The Democratic Republic of the Congo is in the heart of Central Africa while Libya is on the Mediterranean coast of northern Africa. Oman is on the Arabian Peninsula, while Israel is on the Mediterranean shores in the Middle East.

The CDC places a destination at Level 4 when more than 500 cases per 100,000 residents are registered in the past 28 days. The CDC advises travelers to avoid travel to Level 4 countries.

To recap, this week’s additions to Level 4 are:

• Armenia
• Cuba
• Democratic Republic of the Congo
• Israel
• Japan
• Libya
• Oman

Last week, the Democratic Republic of the Congo was at “moderate” Level 2. Armenia, Cuba, Japan, Libya and Oman had been at Level 3, in the “high” risk category.

Israel was added to Level 4 on January 18 along with 21 other destinations and remained there in subsequent updates. However, the CDC listed Israel as an updated entry in Level 4 on Monday because the agency has added information on Gaza and the West Bank. The CDC does not have separate entries in its listing for those.

Other significant places at Level 4

The CDC does not include the United States in its list of advisories, but it was color-coded at Level 4 on February 7 on the agency’s map of travel risk levels.

Last week, Mexico and Brazil were the most notable of a dozen places added to Level 4.

Other tourist favorites parked on Level 4 even longer include Australia, Canada, France, Peru, Singapore and Spain. The United Kingdom has been there since July 2021.

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

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

Ray of hope at Level 3

Cape Town, South Africa, is considered one of the most beautiful urban settings in the world. South Africa moved down to the CDC's Level 3 on Monday.

The Level 3 category – which applies to destinations that have had between 100 and 500 cases per 100,000 residents in the past 28 days – saw three additions on Monday. They were:

• Bangladesh
• Montserrat
• South Africa

South Africa, where the Omicron variant of the coronavirus was first reported, dropped from Level 4, providing a ray of hope for the coming weeks and months that other places will follow suit.

However, the move to Level 3 meant worsening conditions in populous Bangladesh in South Asia and Montserrat, a small British island in the Caribbean. Both had been at Level 2.

Levels 2, 1 and unknown

Destinations carrying the “Level 2: Covid-19 Moderate” designation have seen 50 to 99 Covid-19 cases per 100,000 residents in the past 28 days. This level saw only one addition on Monday: Pakistan. It previously had been at Level 1.

Currently, there are just five destinations at Level 2, including New Zealand, which has some of the world’s tightest travel restrictions.

To be in “Level 1: Covid-19 Low,” a destination must have fewer than 50 new cases per 100,000 residents over the past 28 days.

No destinations were moved to Level 1 on Monday. There are currently only seven destinations in the category. That includes China, which is hosting the Winter Olympic Games.

Finally, there are destinations for which the CDC has an “unknown” risk because of a lack of information. Usually, but not always, these are small, remote places or places with ongoing warfare or unrest. There were no additions this week.

Tanzania, Cambodia and the Canary Islands are among the more-visited locations currently listed in the unknown category. The CDC advises against travel to these places precisely because the risks are unknown.

Cruising

A docked Norwegian Gem cruise ship is seen at the Port of Miami in 2021.

The CDC includes cruise ships on its destinations list.

On December 30, the CDC increased the risk for cruise ship travel to Level 4 and said it should be avoided, regardless of vaccination status. It remained at Level 4 in the newest update.

Meanwhile, the CDC’s Covid-19 guidance has become optional for many cruise ships.

The CDC’s extended conditional sailing order expired recently, and the agency has transitioned to a voluntary program for foreign-flagged cruise ships operating in US waters.

Considerations for travel

Transmission rates are important to consider when making travel decisions, but there are other factors to weigh as well, according Dr. Leana Wen, a CNN medical analyst, emergency physician and professor of health policy and management at the George Washington University Milken Institute School of Public Health.

“The transmission rates are one guidepost,” Wen said. “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.

“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.

She said people should be wearing a high-quality mask – N95, KN95 or KF94 – anytime they’re in crowded indoor settings with people of unknown vaccination status.

Before you travel, it’s also important to consider what you would do if you end up testing positive away from home, Wen said. Where will you stay and how easy will it be to get a test to return home?

Top image: People pass next to Hokan-ji Temple (also known as Yasaka Pagoda) in Kyoto, Japan, on October 14, 2021. (Photo by Carl Court/Getty Images)