Four destinations saw their way onto the Centers for Disease Control and Prevention’s (CDC) “high” risk category for travel on Monday as their COVID situations worsened in recent days.

The Caribbean nation of St Kitts and Nevis, along with Guyana, Mongolia, and Namibia, all moved up the ranks to what is now considered the highest warning level for travel for Americans from the CDC at Level 3.

The CDC’s Level 4 risk category has now been reserved for special circumstances such as extremely high COVID cases or the emergence of a new variant of the virus. There are currently no nations listed in Level 4.

A Level 3 location has more than 100 COVID cases per 100,000 residents reported in the past 28 days, according to the CDC. As of Monday, there were about 115 nations listed in the Level 3 “high” risk category out of the approximately 235 destinations the CDC currently is monitoring for COVID travel risks.

Also listed in the Level 3 “high” risk category is much of Europe, the majority of the Caribbean, and Canada, as well as other popular travel destinations such as Brazil, Costa Rica, Malaysia, Japan, and Thailand.

The CDC warns travelers that visit a Level 3 location to make sure they are up-to-date with their COVID vaccines. But the agency says that “Even if you are up to date with your COVID-19 vaccines, you may still be at risk for getting and spreading COVID-19.”

Two changes were also made to the CDC’s Level 2 “moderate” risk category on Monday with the additions of Guatemala and Zimbabwe.

A Level 2 nation has between 50 to 100 COVID cases per 100,000 residents reported in the past 28 days.

Guatemala saw improvements to its COVID situation, falling from the Level 3 risk category last week, while Zimbabwe’s COVID cases increased in the last week, jumping from Level 1 “low” risk.

Currently, there are about 15 nations listed in the CDC’s Level 2 “moderate” risk category for travel, including locations such as Dominican Republic, Poland, Tunisia, Mexico, Fiji, and Cuba.

Also seeing updates on Monday was the CDC’s Level 1 “low” risk category, which received two additions – Iran and Lebanon. These nations had improvements in their COVID cases as both dropped from Level 2 last week.

A Level 1 destination has 49 or fewer COVID cases per 100,000 residents over the past 28 days, according to the CDC.

Only one nation, Libya, was added to the CDC’s “unknown” risk category this week. The category is reserved for places where reliable information about its COVID situation is not available. Other destinations listed in the “unknown” category include Angola, French Polynesia, Cambodia, Greenland, Macau, Nicaragua, and Samoa.

Tourists visit Maya bay after Thailand reopened its world-famous beach after closing it for more than three years to allow its ecosystem to recover from the impact of overtourism, at Krabi province, Thailand, January 3, 2022. Picture taken January 3, 2022
Tourists visit Maya bay after Thailand reopened its world-famous beach after closing it for more than three years to allow its ecosystem to recover from the impact of overtourism, at Krabi province, Thailand, January 3, 2022. Picture taken January 3, 2022. Reuters / ATHIT PERAWONGMETHA