Washington, Sep 9 (IANS): A fourth American infected with Ebola virus disease arrived back home from West Africa Tuesday morning and will be treated at an Atlanta hospital where the first two Americans successfully recovered.

A specially equipped plane carrying the patient touched down around 9:20 a.m. at Dobbins Air Reserve Base outside Atlanta, Xinhua reported citing US media.

The new patient is reportedly a doctor with the World Health Organisation, but no other information about the patient has been released.

Emory University Hospital said in a statement that the unidentified patient will be brought to the same isolation unit that cared for US aid workers Nancy Writebol and Kent Brantly last month.

Both Writebol and Brantly contracted the deadly virus in West Africa and were later evacuated to the US. The two successfully walked out of the hospital last month after receiving an experimental drug called ZMapp.

Fifty-one-year-old Rick Sacra, the third American aid worker infected with Ebola while working in Liberia, was evacuated back to the US last week. He is being treating in Nebraska Medical Centre's biocontainment unit, a facility specifically designed to care for patients with highly infectious diseases.

On Monday, the World Health Organisation (WHO) said that a doctor working for it in an Ebola treatment centre in Sierra Leone had tested positive for the deadly virus.

It, however, did not disclose the nationality of the patient.