ATLANTA — The fourth U.S. aid worker sickened with Ebola arrived in Atlanta on Tuesday, mirroring the carefully choreographed routine of the two Americans already successfully treated and released from Emory University Hospital’s special isolation unit.

The latest patient — unidentified by hospital officials, who cited privacy restrictions — arrived more than a month after missionaries Dr. Kent Brantly, 33, and Nancy Writebol, 59. All were flown in the same specially equipped medical plane from Africa to a military air base just outside Atlanta, then taken in ambulances with police escorts to the hospital. Helicopters buzzed above, and reporters and television cameras gathered in clusters along the street. The patients wore bulky, protective suits. On Tuesday, Emory’s third patient walked from the ambulance, as Brantly did. Writebol was taken in a stretcher.

The delicate process seemed to run like a well-oiled machine, attracting fewer curious onlookers and drawing less concern from the public the third time around.

“Those of us who are at Emory, we’re not concerned because we know the quality of Emory medical care, and we know the reason they were brought here is because Emory is capable of containing it and treating them,” law student Grace Van Dyke said.

Dr. Aneesh Mehta said the fact that the patient walked is a good sign but emphasized that doctors will look at overhaul health and all options for a treatment plan. Mehta said the medical team’s confidence was bolstered by the first two patients’ recovery.