The U.S. will impose new travel restrictions in response to the Omicron variant, a new COVID strain first detected in South Africa, senior administration officials said Friday.

The big picture: Travel from South Africa, Botswana, Zimbabwe, Namibia, Lesotho, Eswatini, Mozambique and Malawi will be restricted starting on Monday.

• The new policy does not apply to American citizens and permanent residents.
• The restrictions are being implemented “out an abundance of caution,” the administration officials said, adding that this step was recommended by U.S. government medical experts and the COVID-19 Response Team.

The Omicron variant, known formally as B.1.1.529, has already caused countries across Europe and Asia to implement travel restrictions.

• The variant was first reported to the World Health Organization on Nov. 24.
• “This variant has a large number of mutations,” the WHO said in a statement Friday, calling the new strain a “variant of concern.”
• Early evidence suggests “an increased risk of reinfection with this variant compared to other” variants of concern, it added.
• The Omicron variant likely evolved during a chronic infection of an immunocompromised person, possibly in an untreated HIV/AIDS patient, Francois Balloux, director of the UCL Genetics Institute, said in a statement.

Go deeper: New COVID variant concerns South African scientists.

Editor’s note: This story has been updated with additional details.