United Airlines revealed flight numbers for two out of three planes Ebola patient Thomas Eric Duncan reportedly traveled on during his trip to the United States.

The airline said it believed Duncan took Flight 951 from Brussels Airport to Washington Dulles International Airport, then Flight 822 to Dallas/Fort Worth International Airport in a Wednesday statement.

'While the CDC states it is unnecessary for it or the airline to contact others who were on the patient’s flights, United is providing information about the flights United believes the patient took, based on information provided by the CDC,' the airline said. 'We are ensuring our employees have this information and suggest that any customers who have concerns contact the experts at the CDC for further information.'

A third flight number has yet to be released, though Duncan was likely on Brussels Airlines Flight 1247 before boarding the United planes, CBS DFW reported.

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Thomas Eric Duncan reportedly flew from Liberia to Brussels and then into Dallas/Fort Worth International Airport - with a connection in between

Unfriendly skies: Thomas Eric Duncan was able to board a plane to the U.S. and land in Dallas after having come in close contact with at least one person who died of Ebola

Wencke Lemmes, a spokesperson for Brussels Airlines, told MailOnline 'We cannot confirm whether the person in question has been travelling with us or not. Belgian law actually prohibits us to communicate any name of a passenger to external parties nor can we confirm the presence of a person on board of one of our flights - only the authorities are allowed to do so.

'What counts for Brussels Airlines is that independently on whether the person traveled with us or not, CDC states that the person showed no illness symptoms before nor during his travel, hence, there has at no time been a risk of contamination. A person is only contagious if he/she shows illness symptoms.

'In addition, Brussels Airlines has at no time been asked by CDC to inform its guests or staff of its Monrovia flights about the presence of an Ebola patient. The security and safety of our guests and staff remains at all times our first priority and as such we keep monitoring the situation in the three countries hit by Ebola very closely and keep the measures taken in close cooperation with the authorities and medical experts in place.'

A Belgian official also told The Associated Press Duncan flew from Mondovia to Brussels via Brussels Airlines.

United Airlines said it believed Duncan took Flight 951 from Brussels to Washington Dulles International Airport, then Flight 822 to Dallas/Fort Worth International Airport in a Wednesday statement (file photo)

Mystery: A third flight number has yet to be released, though Duncan was likely on Brussels Airlines Flight 1247 before boarding the United planes, an affiliate station reported (file photo)

Travelers: Passengers are seen lined up at Roberts International Airport in Monrovia, Liberia (file photo)

Long journey: Duncan is thought to have flown from Brussels Airport (pictured) to Washington Dulles International

Conservative news blog Gotnews.com published an email from someone claiming to work for United Airlines, which allegedly revealed Duncan's full flight itinerary - including a trip back to West Africa approximately two weeks from now - and alleged that Duncan was a Brussels Airlines Flight 1247 passenger.

The tipster wrote 'I work in reservations for United Airlines. That's all I'm willing to say about my identity.'

'His return flight was scheduled to depart Dallas/Fort Worth (DFW) on Oct. 19,' the alleged email said. 'The return flight was scheduled for DFW-IAD-BRU-FNA (FNA is Lungi Intl Airport in Freetown, Sierra Leone).

United Airlines did not immediately return a request for comment on the allegedly employee-leaked itinerary and if Duncan in fact planned a return trip.

The Centers for Disease Control and Prevention (CDC) did not immediately return a request for comment regarding Duncan's reported flights into the United States.

U.S. officials had previously refused to provide details of Duncan's itinerary, claiming none of his fellow passengers were at risk because he was not showing symptoms at that time.

From Washington Dulles International Airport (pictured), Duncan made his way to Dallas/Fort Worth International Airport, United Airlines believes

The CDC (pictured) is working with U.S. Customs and Border Protection (CBP) to identify potential victims and warn other travelers of the health threat

The New York Times reported that Duncan helped care for a woman who later died of the disease just days before his journey. Had a customs official asked him about his contact with Ebola patients, he could have been flagged as being at high risk for infection.

Public health officials say the chances of an outbreak in the United States are low. The United States has sanitation and medical care that far exceeds that found in the affected West African nations, which are among the poorest in the world.

Currently, patients are checked for fever - the first sign of a possible infection - before they are allowed to board flights leaving West African nations.

However, once travelers gets past examiners in Liberia, Sierra Leone or Guinea, there are few barriers to them moving across the world.

U.S. Customs and Border Protection says the agency's examiners at airports and other ports of entry are trained to spot and identify people potentially infected with Ebola before they enter the country.

It's a long way to Texas: Thomas Duncan flew from Liberia to Belgium to Washington, D.C., before finally arriving in Dallas on September 20

However, a spokeswoman could provide no information about how the agency was changing its rules to prevent more Ebola infected fliers from coming into the U.S.

Airlines for America, the industry trade group, on Wednesday U.S. airlines are in regular contact with the Centers for Disease Control and other government agencies about helping to prevent the spread of Ebola.

'A4A members that fly to affected countries remain in steady contact with government agencies and health officials, and have procedures in place to monitor and quickly respond to potential health concerns,' spokeswoman Victoria Day said.

Stocks in major U.S. air carriers fell as much as nearly 4 percent on Wednesday over fears that the spread of the worst known Ebola outbreak beyond West Africa would make more customers fearful of traveling.

'People are nervous about (the first case of Ebola detected in the United States) and what it means,' said Michael Derchin, an analyst at CRT Capital Group LLC.

Still, Derchin said that the market had overreacted.

'I would be surprised if there's any impact on travel,' he said.

JetBlue Airways and American Airlines said they were closely following guidelines from the U.S. Centers for Disease Control and Prevention (CDC).

Airlines for America, the industry trade group, is also coordinating with the CDC on any government action related to Ebola concerns, JetBlue spokesman Morgan Johnston said.

'We follow the guidelines (put) in place by the CDC specifically for airlines, and we work with our crews to protect the health of our customers and employees,' American Airlines spokesman Josh Freed said.

The CDC is working with U.S. Customs and Border Protection (CBP) to identify potential victims and warn other travelers of the health threat.

'CBP personnel receive training in illness recognition,' said agency spokeswoman Jennifer Evanitsky. If they identify someone believed to be infected, they will seek medical evaluation from CDC and local health officials.

Customs officials will wear protective equipment such as gloves and surgical masks to ensure their safety when interacting with ill travelers, she added.

Customs and Border personnel also will hand out flyers in airports encouraging people to watch their health for 21 days and listing steps to follow should they become sick, according to CDC spokesman Tom Skinner.

Airlines will also remind their customers to follow CDC guidelines regarding travel when ill, Johnston said.