All airline passengers will need proof of negative COVID test to enter US

U.S. health officials are taking critical steps toward slowing the spread of COVID-19. 

The Center for Disease Control and Prevention said Tuesday that it is expanding the requirement for a negative COVID-19 test to all air passengers entering the country.

The agency said testing before and after travel is crucial to stemming the virus's spread, especially with new strains popping up. 

"Variants of the SARS-CoV-2 virus continue to emerge in countries around the world, and there is evidence of increased transmissibility of some of these variants," the CDC said in a statement. 

Before coming to the U.S. by plane, air passengers will be required to get a COVID test within three days of their flight and provide written documentation of their laboratory test results to their airline.

If a passenger does not have proof of a negative COVID test or chooses not to take a test, the airline is required to deny boarding, officials said. 

The CDC also recommends people get tested again 3-5 days after arrival and stay home for seven days post-travel. 

The new travel order goes into effect on Jan. 26.

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