The Department of Homeland Security is set to implement new entry restrictions beginning Thursday for foreign travelers coming to the United States from countries at the center of the latest Ebola outbreak.

According to a draft of a new DHS rule scheduled to be published Thursday, all U.S.-bound flights carrying foreign travelers who have been in Congo, Uganda or South Sudan at any point in the previous 21 days will be required to fly into Washington-Dulles International Airport in Virginia.

The arrival restrictions, issued at the direction of Homeland Security Secretary Markwayne Mullin, are designed to funnel those travelers to an airport "where the U.S. government is focusing public health resources to implement enhanced public health measures," the rule states.

The rule applies only to passenger flights, DHS said, with cargo flights excluded from the restrictions.

In a statement provided to CBS News, a DHS spokesperson confirmed the new travel requirements, saying that "to reduce the risk of the Ebola virus spreading," Customs and Border Protection is "enhancing public health screening, travel monitoring, and health protection response activities."

The DHS spokesperson added that CBP was coordinating with "airlines, international partners and port-of-entry officials to identify and manage travelers who may have been exposed to the Ebola virus."

In its rule, DHS did not disclose what kind of specific protocols foreign travelers will have to undergo upon arrival at Dulles.

The move comes two days after the U.S. Centers for Disease Control and Prevention also issued travel restrictions linked to the Ebola outbreak. The CDC announced Monday that people without U.S. passports who had traveled to Congo, Uganda or South Sudan in the past three weeks would be restricted from entering the country.

It's unclear how the new DHS rule impacts the CDC's order.

On May 15, the Africa Centres for Disease Control and Prevention confirmed an Ebola outbreak in eastern Congo. World Health Organization Director-General Tedros Ghebreyesus said Wednesday there are at least 600 suspected Ebola cases so far, included 139 suspected deaths from the virus. Ghebreyesus said the virus is believed to have been circulating for some time before it was detected.

A U.S. doctor working with a missionary organization in Congo contracted Ebola and was transported to Germany for medical treatment, the U.S. CDC and his missionary group said Tuesday. At least six Americans were exposed to the virus, sources told CBS News Monday.

Health officials say the new outbreak is linked to the Bundibugyo strain, for which there are no approved vaccines or treatments, according to CBS News medical correspondent Dr. Céline Gounder. 

WHO has declared the outbreak a public health emergency of international concern, but says as of now it falls short of the criteria for a pandemic emergency.