Why the CDC Won't Release the Ebola Patient's Flight Itinerary

— -- The flight information for the Ebola patient diagnosed in Texas will not be released by health officials because "It's just not necessary," a spokesperson at the U.S. Centers for Disease Control and Prevention told ABC News.

The CDC announced that the man has tested positive for the disease, making him the first person to have discovered he had the virus while on U.S. soil, and they made it clear that he traveled from Liberia to America to visit family in Dallas.

"If we need to contact passengers we have a way. We'd call ourselves," the CDC spokesperson said.

Even though the CDC will not release his flight plan from Liberia to the United States, it is clear that he would have had to make at least two transfers -- including one in at least one other country.

Flights from the airport in the Liberian capital of Monrovia fly to only six destinations -- four in West and Central Africa, one flight to Morocco and one flight to Brussels, Belgium. There are no direct flights into the Dallas-Fort Worth International Airport from any of those six destinations, meaning that man had to make at least one more change.

The CDC said Tuesday that the passengers who unknowingly traveled with the man need not be concerned because he was not contagious while he was on the plane.

"The ill person did not exhibit symptoms of Ebola during the flights from West Africa and CDC does not recommend that people on the same commercial airline flights undergo monitoring, as Ebola is only contagious if the person is experiencing active symptoms," the agency said in a statement Tuesday.

The man left Liberia on Sept. 19 and arrived in Texas on Sept. 20, CDC Director Tom Frieden said.

"Ebola doesn't spread before someone gets sick and he didn't get sick until four days after he got off the airplane," Frieden noted during a news conference Tuesday.

On his first visit to the hospital, doctors did not immediately conclude that he had Ebola and they sent him home but he returned with much more drastic symptoms on Sept. 27, according to the CDC. He was put in a special isolation unit the following day.

Part of the problem in diagnosing Ebola comes from the fact that patients, like this man, can take up to 21 days to exhibit symptoms such as fever, muscle pain, vomiting and bleeding.

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