The Centers for Disease Control and Prevention is advising against travel to Poland, Trinidad and Tobago, Niger and Papua New Guinea, regardless of vaccination status.
The four destinations were moved to the CDC’s “level 4” COVID-19 advisory list, which includes destinations the agency believes should be avoided by U.S. travelers. Travelers who "must" travel to these destinations should be fully vaccinated, the CDC says.
The shift comes as the world grapples with the latest COVID-19 variant, omicron, which was announced as a “variant of concern” on Friday. None of the countries the CDC moved to "level 4" have reported cases of the new variant within their borders as of Tuesday.
The CDC looks at a variety of data when determining which travel health notice level to assign a country, including new case counts and testing rates.
► CDC travel warning: Avoid travel to Denmark and Germany, regardless of vaccination status
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Trinidad and Tobago, a Caribbean nation located off the coast of Venezuela, reported more than 4,000 cases the week of Nov. 22, up 22% from the week prior, while Niger, located in western Africa, reported a 33% increase in cases, according to WHO. Papua New Guinea reported a 61% drop in cases the week of Nov. 22 but a 5% increase in reported deaths tied to the virus.
The CDC also dropped a handful of countries from its level 4 tier. Costa Rica, Bermuda, French Polynesia and Guyana are now at level 3, with the CDC suggesting travelers make sure they are fully vaccinated before traveling to these destinations or avoid nonessential travel if unvaccinated.
The British Virgin Islands and the Democratic Republic of the Congo were dropped down to level 1, which means travelers should make sure they are fully vaccinated before travel, according to the CDC.
Follow USA TODAY reporter Bailey Schulz on Twitter: @bailey_schulz.
This article originally appeared on USA TODAY: CDC advises against Poland, Trinidad and Tobago trips due to COVID