A fourth American aid worker infected with Ebola walked into Emory University Hospital today after arriving on a medical plane. The patient, a doctor who contracted the virus in Sierra Leone, arrived at 10.20am by ambulance, with a police escort, at the Atlanta hospital to be housed in a special isolation unit. Wearing a bulky protective suit similar to those of Emory's first two arrivals, the patient walked from the ambulance to the hospital - though a different entrance was used this time around. Reporters and television cameras - but fewer curious onlookers - lined the street. Scroll down for video
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The plane touched down around 9.20am at Dobbins Air Reserve Base in Marietta, just northwest of Atlanta
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The patient, whose identity has not been released, will be kept in isolation
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The World Health Organization said separately that a doctor who has been working in an Ebola center in Sierra Leone tested positive for the disease
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WHO said the doctor was in stable condition and was being evacuated
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Dr. Kent Brantly and Nancy Writebol, were treated successfully at Emory
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Dr Rick Sacra, 51, is being treated at the Nebraska Medical Center in Omaha - he is stable and ate breakfast on Monday, according to family
The ambulance driver was pictured on Tuesday morning wearing a protective suit and face-mask while driving to @placeholder