The CDC announced Tuesday that all international travelers, including U.S. citizens traveling from abroad, must test negative for COVID-19 before boarding a flight heading to America.
The new travel restriction will take effect starting Jan. 26.
The CDC’s order is apparently aimed at preventing further spread of the novel coronavirus, and it comes as international travel begins to pick up amid a surge of COVID-19 across the U.S.
Flights from the U.S. dried up last spring as the pandemic took hold but have risen steadily since then.
Airlines are ordered to stop passengers from boarding if they don’t have proof of a negative test or a prior infection.
"Testing does not eliminate all risk," CDC Director Robert R. Redfield said in a statement. "But when combined with a period of staying at home and everyday precautions like wearing masks and social distancing, it can make travel safer, healthier, and more responsible by reducing spread on planes, in airports, and at destinations."
Millions of people passed through U.S. airport security checkpoints over the Thanksgiving and Christmas holidays, despite health experts’ pleas to stay home amid rising cases.
U.S. tourists flocked to Mexico's Caribbean coast over Christmas and New Year's.
FILE - Medical staff in protective suits wait on the tarmac for the German national handball team to land at Cairo airport ahead of the start of the 2021 Handball World Cup in Egypt.
Health experts fear the increase in travel, both domestic and international, through the holiday season will lead to spikes in places that previously seemed to have the virus under control.
"In the most popular tourist destinations, you’re going to have epidemic activity increase again in a big way," said Dr. Mauricio Rodríguez of the medical school at Mexico’s National Autonomous University, citing beach destinations like Puerto Vallarta, Acapulco, Quintana Roo and the Riviera Maya.
And according to the CDC, travelers who have visited the following countries in the past 14 days are already barred from entering the U.S.: China, Iran, Austria, Belgium, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Italy, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland, Monaco, San Marino, Vatican City, England, Scotland, Wales, Northern Ireland and Brazil.
The virus is responsible for killing more than 1.9 million people across the globe, with the U.S. surpassing 379,000 deaths as of Jan. 12, according to Johns Hopkins University.
The Associated Press contributed to this report.