MARGERY A. BECK, Associated Press

OMAHA, Neb. (AP) — A doctor who became infected with Ebola while working in Liberia — the third American aid worker sickened with the virus — is expected to arrive at a Nebraska hospital for treatment.

Officials at the Nebraska Medical Center in Omaha have said 51-year-old Dr. Rick Sacra is expected Friday and will begin treatment in the hospital’s 10-bed special isolation unit, the largest of four such units in the U.S.

Dr. Phil Smith, medical director of the unit, said doctors will focus on care such as keeping Sacra hydrated and keeping his vital signs stable. A team of 35 medical staffers will attend to him.

Smith and other doctors said Sacra’s transfer to Omaha posed no threat to the public, noting Ebola is transmitted through close contact with an infected person.