(CNN) — The US Centers for Disease Control and Prevention on Tuesday added three destinations in Europe -- from its frigid northern climes to its sun-soaked south -- to its highest-risk category for travel.
In its weekly update of Covid-19 travel advisories, the CDC advised against travel to the following countries and placed them in its "Level 4: Covid-19 Very High" category:
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 island nation of Malta, a Mediterranean favorite, was also at Level 3 last week.
Far off the radar of most tourists, the eastern European nation of Moldova had previously been in the "Unknown" category. The CDC places destinations in that category when it doesn't have enough reliable data to make an assessment.
Europe's continuing woes
In another troubling sign for Europe's Covid-19 situation, the CDC moved no destinations on that continent to a lower level in the past week.
Other big travel names that remain lodged at the CDC's Level 4 include:
• United Kingdom
In fact, the United Kingdom has been at Level 4 since July 19.
However, Europe isn't the only continent with popular tourist destinations on Level 4. Among the other places also considered at "very high" risk for travel are:
• South Africa
In all, almost 90 destinations were rated Level 4 as of December 28. You can view the CDC's risk levels for global destinations on its travel recommendations page.
Level 3 additions
A general view of the Obelisco de Buenos Aires in Argentina's largest city.
Ricardo Ceppi/Getty Images
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 two additions Tuesday:
Argentina, a South American travel favorite that took a very cautious approach about letting in foreign visitors for most of the pandemic, had previously been at Level 2.
The move was good news for the tiny Islamic sultanate of Brunei, which had been at Level 4.
Level 2, Level 1 and unknowns
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. That level saw three additions Tuesday:
Cuba, the largest island in the Caribbean, had been at Level 3. Gabon, on Africa's Atlantic Coast along the equator, and Guatemala, in Central America. had also been at Level 3,
In the category of "Level 1: Covid-19 Low" destinations, fewer than 50 new cases per 100,000 residents have been logged over the past 28 days. It saw just one addition -- the island nation of São Tomé and Príncipe off the coast from Gabon.
Finally, there are destinations, as cited above, for which the CDC has an "unknown" risk because of a lack of information. Usually, these are small, remote places. On Tuesday, the CDC added three places to this category:
• French Polynesia
• New Caledonia
The CDC cautions even fully vaccinated travelers about venturing to destinations with no reliable statistics about the current Covid-19 situation.
In its broader travel guidance, the CDC has recommended avoiding all international travel until you are fully vaccinated.
"Fully vaccinated travelers are less likely to get and spread Covid-19. However, international travel poses additional risks, and even fully vaccinated travelers might be at increased risk for getting and possibly spreading some Covid-19 variants," the agency said.
Another tumultuous week
All of these CDC level changes are happening against a swirl of pandemic news affecting travel worldwide:
• Cruises: At least four ocean cruise ships were recently turned away from ports of call or were prohibited from letting passengers disembark in the Americas this week because of Covid-19 cases aboard. Find out more here. • Air travel: Thousand of flights were canceled over the Christmas holiday weekend in part because workers were calling in sick with Covid-19 cases. Find out more here. • New Year's Eve: Big shindigs are being called off or trimmed down around the world. New York is holding a scaled-back gathering in Times Square, but London has called off its big party completely. Find out more here. • Travel ban to be lifted: President Joe Biden issued a presidential proclamation Tuesday, December 28, revoking a proclamation from last month that enacted travel restrictions on eight southern African nations, including South Africa, as the Omicron variant began to spread. The proclamation repeals the ban as of 12:01 a.m. ET December 31. Find out more here.