A fourth American who contracted Ebola in West Africa was expected to arrive in the U.S. for care on Tuesday and will seek care at an Atlanta hospital where two other aid workers were successfully treated for the disease, The Associated Press reported on Monday.

Air Force spokesman Lt. Col. James Wilson said the patient would be flown into Dobbins Air Reserve Base outside Atlanta, as in past cases. Emory University Hospital said in a news release that the patient would be treated in its isolation unit but said confidentiality is stopping them from releasing more information about the person.

The World Health Organization said one of its doctors working in Sierra Leone at an Ebola treatment clinic has tested positive for the disease. The organization said the doctor was in stable condition Monday in Freetown and will be evacuated as soon as possible. The State Department said the doctor was from the U.S.

The family of Dr. Rick Sacra said he was able to eat breakfast for the first time on Monday since arriving at the Nebraska Medical Center in Omaha on Friday, according to USA Today.

The 51-year-old is still in stable condition. His wife, Debbie, said Sacra is more alert and that they had a half-hour conversation by video conference Sunday.

"He hasn't been able to eat much since he got here, but he had some toast and apple sauce," Debbie Sacra told USA Today. "He also tolerated the research drug well - better than he had the previous doses he was given."

Rick Sacra, a doctor from Worcester, Massachusetts, spent 15 years working at the Liberia hospital where he became ill with the virus. He was a family doctor in Liberia with the North Carolina-based charity SIM.

Authorities say an estimated 2,100 people have died during the Ebola outbreak in West Africa, but Ebola hasn't been confirmed as the cause of all those deaths.