An American doctor who contracted Ebola while treating victims of the deadly virus in Liberia has recovered and will be discharged Thursday by the Atlanta hospital that treated him with an experimental drug, his charity said.

Dr. Kent Brantly of Texas was given ZMapp, a drug used on a handful of patients in the West African outbreak and produced by U.S.-based Mapp Biopharmaceutical.

Brantly, 33, is expected to speak at a news conference on Thursday at Emory University Hospital, where he and U.S. missionary Nancy Writebol have been treated since being evacuated from Liberia earlier this month.

The hospital said it would discuss the discharge of both patients.

Brantly will leave Emory's hospital after the news conference, a spokesman for the Christian charity Samaritan's Purse said. No timetable was given for Writebol, 59, of Charlotte, North Carolina, who also has been treated with ZMapp.

"I have marveled at Dr. Brantly's courageous spirit as he has fought this horrible virus with the help of the highly competent and caring staff at Emory University Hospital," Franklin Graham, president of Samaritan's Purse, said in a statement.

The World Health Organization said Wednesday that 2,473 people have been infected and 1,350 have died since the Ebola outbreak was identified in remote southeastern Guinea in March.

It said that no cases of the disease had been confirmed outside of Guinea, Sierra Leone, Liberia and Nigeria despite cases having been suspected elsewhere.

A senior health official in Togo said on Thursday that two suspected cases, including a sailor from the Philippines, were being tested for the virus.

Three African doctors, also treated with ZMapp in Liberia, have shown remarkable signs of improvement, Liberian Information Minister Lewis Brown said Tuesday.

Mapp says its supplies of the drug have been exhausted.