WASHINGTON — The U.S. government will increase measures aimed at preventing entry by people exposed ​to Ebola with a new requirement for U.S.-bound air ‌travelers to attest they have not been in the Democratic Republic of Congo in the prior 21 days, according to a memo on ​Thursday seen by Reuters.

The U.S. Centers for Disease Control ​and Prevention in May adopted rules barring airline passengers who have been in the DRC, the center ⁠of the 2026 outbreak, in the prior three weeks. The restrictions were ​extended to U.S. citizens in July.

The new CDC order takes ​effect November 3 and requires all U.S.-bound airline passengers to file digital or paper attestations.

Airlines for America, which represents United Airlines, American Airlines, Southwest ​Airlines and Delta Air Lines, did not immediately comment.

The CDC ​is holding briefing calls with major U.S. and foreign airlines on Friday to ‌detail ⁠how carriers should comply with the new requirements.

As part of the Ebola measures, the CDC since earlier this year has also barred foreign nationals from the U.S. if they have been ​in Uganda or ​South Sudan ⁠in the prior three weeks.

The Bundibugyo strain of the virus spread undetected for months before the ​outbreak was declared in May. It kills about ​half ⁠of those infected and has no approved treatment or vaccine.

So far the outbreak is confirmed to have killed about 4,700 people ⁠in Africa, ​according to the Africa CDC.

To date, ​no Ebola cases associated with this outbreak have been reported in the United ​States, the CDC said.

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