CDC: International passengers coming into US must prove they do not have COVID-19

ATLANTA - If you are planning to travel internationally, your flight back to the US just got a little more complicated.

Under a new CDC regulation, before you can board your return flight to the US, you will need to show proof you have tested negative for COVID-19 within 3 days of your flight.

If you don't have paper or electronic proof of a negative viral test, the agency says, your airlines will not permit you to board your flight.

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If you have recently had COVID-19, the CDC says you will need to have proof of a recent positive COVID-19 test result and a letter from your healthcare provider stating you were cleared to travel. 

The new requirement comes as the US moves towards barring travelers who are not US citizens or legal permanent residents from coming into the country from Brazil, South Africa, Britain, and Ireland.

Federal health authorities are trying to keep 3 new variants of the coronavirus, which are much more transmissible, and, in the case of the UK variant, possibly more lethal, from gaining a foothold in the US.

"So, the travel bans are always stressful, especially for those people whose livelihood depends on travel," Dr. Colleen Kraft, an Emory infectious disease physician says.  "It's just one of the ways we're trying to figure out to be absolute in stopping some of this transmission."

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As states ramp up vaccinations, there are questions about whether the two FDA-approved COVID-19 vaccines will be effective against the mutated strains of the virus.

One vaccine manufacturer, Moderna, is already working on a "plan B" vaccine, a booster shot designed to target the South African variant of the virus.

Dr. Kraft says the newer mRNA vaccine technology used to create both FDA-approved vaccines makes them easier to tweak than the flu vaccine.

Still, she says, the best protection against these more transmissible variants is wearing masks.

Kraft says if everyone wore a mask consistently, that could stop the spread of these new variants.   

Some experts recommend upgrading to a medical-grade mask, if available, or doubling up on masks, especially in indoor settings, which tend to be high-risk.

"So, wearing a more substantial mask or a heavier mask, I think, is fine," Kraft says.  "But, again, we just need everybody to take ownership and do that at the same time.  That's what's going to cut down our transmission the quickest. "

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