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ATLANTA - The Centers for Disease Control and Prevention has added a number of places to an advisory list that warns against travel due to the continuing spread of the novel coronavirus and its contagious omicron variant.
According to the CDC, 15 new destinations were cited Monday as a level four — meaning "very high risk" — for Americans.
Those cities include Columbia, Costa Rica, Fiji, Jamaica, Kuwait, Mongolia, Peru, Romania, Saint Martin, Tunisia, the United Arab Emirates and the Dominican Republic.
Countries are given a "Level 4" designation when more than 500 COVID-19 cases per 100,000 residents are registered in the past 28 days.
Travel to the 15 new destinations has been discouraged by the health agency. Those who must travel to these destinations are encouraged to be fully vaccinated against COVID-19 prior to their trip.
"Do not travel internationally until you are fully vaccinated," the advisory said. "Getting vaccinated is still the best way to protect yourself from severe disease, slow the spread of COVID-19 and reduce the number of new variants. CDC encourages you to get a COVID-19 vaccine booster dose if you are eligible. People who are not fully vaccinated should follow additional recommendations before, during and after travel."
A scenic view of aircraft flying overhead photographed on November 29, 2010 in Raleigh, North Carolina. (Photo by Bruce Bennett/Getty Images)
The CDC added that people should follow all airline COVID-19 requirements and any requirements at these destinations. It is recommended individuals get tested with a viral test one to three days before a trip.
The agency also noted that preventative health requirements for travelers in other countries may differ from the U.S.
"If you do not follow your destination’s requirements, you may be denied entry and required to return to the United States," the agency added.
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This news comes just one week after the CDC warned against travel to 22 nations and territories as COVID-19 cases surged.
Those countries included: Albania, Argentina, Australia, Bahrain, Bermuda, Bolivia, Cape Verde, Egypt, Grenada, Guyana, Israel, Panama, Qatar, Saint Kitts and Nevis, Saint Lucia, São Tomé and Príncipe, Sint Maarten, Suriname, the Bahamas, the British Virgin Islands, the Turks and Caicos Islands and Uruguay.
Earlier this month, the agency also put Canada on that list.
"Because of the current situation in Canada, even fully vaccinated travelers may be at risk for getting and spreading COVID-19 variants," the CDC said.
FOX News contributed to this story. This story was reported from Los Angeles.