(CNN) — After more than six months in the U.S. Centers for Disease Control and Prevention’s lower-risk level 3 travel category, Mexico moved to “very high” risk level 4 along with 11 other destinations on Monday.
Of the 12 destinations added to Level 4, five were in South America: Brazil, Chile, Ecuador, Paraguay and French Guiana (an overseas territorial community of France).
In the Caribbean, Anguilla and Saint Vincent and the Grenadines moved to Level 4.
Singapore and the Philippines in Southeast Asia also ranked in the highest risk category, as did Moldova and Kosovo in Europe.
The CDC places a level 4 destination when more than 500 cases per 100,000 population have been registered in the past 28 days. The CDC advises travelers to avoid traveling to Level 4 countries.
To summarize, the 12 places added this week are:
• French Guyana
• The Philippines
• Saint Vincent and the Grenadines
Brazil was added to the CDC’s highest-risk travel category on Monday. Ipanema Beach in Rio de Janiero is pictured here on January 20.
Carl de Souza / AFP via Getty Images
Nearly every addition to level 4 was at level 3, or “high” risk for Covid-19, last week. The only exception is French Guiana, which was listed as “unknown” last week due to a lack of information.
Level 3 Additions
Nepal moved up from Level 2 to Level 3 on Monday. Kathmandu, Nepal, is pictured here on October 15, 2021.
Rebecca Conway/Getty Images
The level 3 category – which applies to destinations with between 100 and 500 cases per 100,000 inhabitants in the past 28 days – saw 11 additions on Monday:
• French Polynesia
There are no destinations below Level 4 this week. Six were previously on Level 2: Brunei, Comoros (an archipelago off the coast of East Africa), Guinea-Bissau, Honduras, Liberia and Nepal.
Bhutan, Guinea, Gambia and Oman have increased two levels of risk from level 1.
Last week, French Polynesia was listed in the “unknown” category.
Levels 2, 1 and unknown
New Zealand, with the city of Wellington pictured here in 2020, stayed at Level 2 this week.
Hagen Hopkins/Getty Images AsiaPac/Getty Images
Destinations labeled “Level 2: Covid-19 Moderate” have seen 50 to 99 Covid-19 cases per 100,000 population in the past 28 days.
There were no additions to Level 2 on Monday. Currently, there are only seven destinations on Level 2, including New Zealand, which has some of the world’s strictest travel restrictions.
To be in “Level 1: Covid-19 Low”, a destination must have fewer than 50 new cases per 100,000 inhabitants in the past 28 days.
No destinations moved to Level 1 on Monday. There are currently eight destinations in the category, including China, which will host the Winter Olympics in February.
Finally, there are destinations for which the CDC has an “unknown” risk due to lack of information. Usually, but not always, these are small, remote places or places of ongoing war or unrest. There were no additions this week.
Tanzania, Cambodia and the Canary Islands are among the locations currently listed in the unknown category. The CDC does not recommend traveling to these places precisely because the risks are unknown.
A docked Norwegian Gem cruise ship is seen in the Port of Miami in 2021.
Chandan Khanna/AFP/Getty Images
On Dec. 30, the CDC raised the risk for cruise ship travel to Level 4 and said it should be avoided regardless of vaccination status. It stayed at level 4 in the latest update.
Transfer rates are important to consider when making travel decisions, but there are other factors to consider as well, according to Dr. Leana Wen, a CNN medical analyst, emergency department and professor of health policy and management at the George Washington University Milken Institute School of Public Health.
“The transmission rates are one guideline,” Wen said. “Another is what precautions are required and followed where you are going and the third is what you plan to do once you get there.
“Do you plan to visit a lot of attractions and go to indoor bars? That’s quite different from going somewhere where you plan to lie on the beach all day and not interact with anyone else. That’s very what else. Those are very different levels of risk.”
Vaccination is the most important safety factor for travel, as unvaccinated travelers are more likely to get sick and transmit Covid-19 to others, Wen said.
She said people should wear a high-quality mask – N95, KN95 or KF94 – when they are in a crowded indoor environment with people of unknown vaccination status.
Before traveling, it’s also important to consider what you would do if you tested positive outdoors, Wen said. Where will you stay and how easy will it be to pass a test to go home?
Top photo: People spend time on the beach in Tulum, Mexico, on Oct. 30, 2021. (Daniel Slim/AFP via Getty Images)