Ebola Virus Kent Brantly
Kent Brantly, pictured here, is set to be released from hospital.Twitter / @eriktryggestad

An American doctor who contracted the deadly Ebola virus while working for a Christian aid organisation in Liberia is set to be released from hospital after recovering.

Dr Kent Brantly was working for Samaritan's Purse in Liberia treating patients with the disease when he contracted the virus himself.

Earlier this month, Brantly was flown by private air ambulance, specially equipped to isolate patients with infectious diseases, to Dobbins Air Reserve Base in north-west Atlanta.

He was then driven by ambulance, with a police escort, to Emory University Hospital where there is a containment unit for patients with infectious diseases. He was given experimental treatment.

Another US aid worker who contracted the virus in Liberia, Nancy Writebol, is to be discharged from the Emory University Hospital's isolation unit but it was not clear whether she would be released from the facility also.

Franklin Graham, president of the Samaritan's Purse organisation, said he had "marveled at Dr. Brantly's courageous spirit as he has fought this horrible virus".

According to new United Nations figures, more than 1,300 people have now died since the beginning of this year in the outbreak that has hit Sierra Leone, Liberia, Guinea and Nigeria. The World Health Organization said there were 84 deaths between 14 and 16 August alone.

The highly contagious disease is one of the deadliest in the world and does not yet have a known cure.

The symptoms of the virus include fever, sore throat, diarrhoea and internal and external bleeding, with a 90% fatality rate.