SAN FRANCISCO (CBS SF) — Under new guidelines the CDC will require travelers to take a COVID test within three days before their plane departs from any foreign country for the US starting January 26.

Passengers ages two and older will need to show documentation of their result via PCR or rapid antigen tests on paper or electronic form to an airline employee.

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Those who have previously had COVID-19 must show official proof that they’ve recovered from their illness.

Travel website and blog The Points Guy says since the announcement, airlines have reported seeing a drop in bookings.

“There are some who argue that people should not be traveling internationally anyway, because we still don’t have the vaccine widely available,” said Senior News Editor Clint Henderson. “In the short term this is not going to be great. However, in the long-term, this could be part of a new process that makes it a little safer for international travel.”

Henderson says this will affect many Americans visiting and returning from Mexico, which has been an appealing destination because of the lack of restrictions and a relatively short flight from the San Francisco Bay Area.

“They are doing free COVID tests for … people that stayed at their resort,” said Diane Burns, who just returned to the Bay Area from Puerto Vallarta.

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Burns said the resort would have made it feasible to follow the new order.

“I’d feel comfortable, I’d want to find out before I left what it was like to get a negative test, or get a test,” said John Burns of Redding.

White House officials confirmed to CBS News that President Joe Biden is expected to announce, possibly as early as Monday, a ban on most non-US citizens entering the country, who have recently been in South Africa.

South Africa is dealing with a new, potentially more deadly variant of COVID.

The president is also expected to reimpose an entry ban on nearly all non-US travelers who have been in Brazil, The United Kingdom, Ireland and 26 countries in Europe.

“The best way to prevent the further evolution of these mutants is to vaccinate as many people as possible with the vaccines that we have currently available to us,” said Dr. Anthony Fauci on Face the Nation Sunday.

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