By Staff Reporter (staff@latinospost.com) | First Posted: Aug 22, 2014 10:29 AM EDT

A U.S. missionary who contracted the deadly Ebola virus in Liberia is better after being released from an Atlanta hospital but still regaining her strength, her son said on Friday.

Nancy Writebol, 59, of Charlotte, North Carolina, was discharged earlier this week from Emory University Hospital after doctors said her symptoms had eased and blood and urine tests showed no evidence of the virus. Dr. Kent Brantly, who also was stricken with Ebola in Liberia, was released on Thursday.

"She's tired and trying to rest," her son Jeremy told NBC. "There's still some physical recovery that has to go on there. But her color's good and strong. She seems pretty happy."

Speaking alongside his brother Brian, he said the family has experienced "the lowest of lows and at the same time the highest of highs" since Writebol contracted the Ebola virus in July while working for a Christian mission organization in Liberia, grappling first with her potential death and later her recovery.

He said faith, the care at Emory and the experimental drug ZMapp likely helped her survive the virus, which has a low survival rate. Ebola can kill up to 90 percent of those who become infected, although the fatality rate in the current epidemic is about 60 percent.

Nancy's husband, David, had been in quarantine after returning from Africa but the two have since reunited.

Jeremy Writebol has said the couple has not ruled out returning to their Christian mission work in West Africa.

"She still thinking about it," he told NBC. "Africa's still in their heart and the suffering of the people in western Africa is still very deep for them."

The Ebola outbreak in West Africa is the largest in history, with more than 2,470 people infected and at least 1,350 dead. On Friday, the World Health Organization announced a draft plan to combat the virus for the next six to nine months, signaling it does not expect to stop the epidemic this year.

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