The patient, who has been hospitalized in Dallas, traveled to the U.S. from Liberia earlier this month and did not exhibit any symptoms at the time of his flight.
The CDC, however, wants to also temper the fear that might result from the news.
"Ebola can be scary. But there's all the difference in the world between the U.S. and parts of Africa where Ebola is spreading. The United States has a strong health care system and public health professionals who will make sure this case does not threaten our communities," CDC Director Dr. Tom Frieden, MD, MPH, was quoted as saying on the CDC website. "While it is not impossible that there could be additional cases associated with this patient in the coming weeks, I have no doubt that we will contain this."