Two American aid workers who were infected with Ebola have been discharged from an Atlanta hospital, where doctors say they pose no risk to public safety.

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

HEALTH-EBOLA/LIBERIA

The current Ebola outbreak in West Africa is the largest ever, and officials have said that treatment centres, especially in Liberia, are filling up faster than new ones can be opened or expanded. (2Tango/Reuters)

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

"Today is a miraculous day," Brantly said. "I am thrilled to be alive, to be well, and to be reunited with my family."

He thanked his charity, Samaritan's Purse, Writebol's SIM International and his medical team.

Writebol was discharged on Tuesday, said Dr. Bruce Ribner, medical director of the infectious disease unit at Emory University Hospital.

In a separate statement, Christian mission group SIM USA said Writebol was released from the hospital on Tuesday and was resting in an undisclosed location with her husband.
 
"Nancy is free of the virus, but the lingering effects of the battle have left her in a significantly weakened condition," her husband, David Writebol, said in a statement. "We decided it would be best to leave the hospital privately to be able to give her the rest and recuperation she needs at this time."

Discharge decisions are made on a case-by-case basis, Ribner said.

"After a rigorous course of treatment and thorough testing, we have determined, in conjunction with the Centers for Disease Control and state government, that Dr. Brantly has recovered from the Ebola virus infection and that he can return to his family, to his community and to his life without public health concerns," Ribner said.

The treatment team used standard guidelines from the World Health Organization and U.S. Centers for Disease Control and Prevention, such as the absence of virus in the blood and symptom improvements for at least two days, Ribner said.

"It was the right decision to bring these patients back to Emory for treatment," Ribner said.

Ribner said he hopes the Emory treatment team can apply what they've learned to assist medical colleagues who are treating Ebola patients in West Africa.

Writebol, 59, of Charlotte, North Carolina, was also treated with ZMapp.

Ribner said it's not clear what role, if any, the experimental treatment played in their recovery.

"We knew the key to resolving Ebola virus infection was aggressive supportive care," he said.

The World Health Organization said Thursday it's convening talks with more than 100 experts Sept. 4-5 in Geneva to discuss experimental treatments and vaccines for Ebola, including ZMapp. More than 20 experts from West Africa are expected to attend.

The UN health agency also noted clinicians said a nurse and one of the two doctors treated with ZMapp in Liberia show a marked improvement. The condition of the second doctor is serious but has improved somewhat. A Spanish priest who received the treatment died.

The WHO said on 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.

With files from Reuters and Associated Press