By Jacque Wilson
(CNN) -- Dr. Rick Sacra is the latest American to become infected with the Ebola virus while working in West Africa for the aid organization Serving in Mission, its president said Wednesday.
Johnson announced Sacra's name at a news conference in which Writebol spoke publicly for the first time about her ordeal.
From Charlotte, North Carolina, Writebol thanked God, her family, and health care workers in Liberia and Atlanta for nursing her back to health.
"I'm so grateful that this beautiful woman is still with me," her husband David said. "She is the best part of my life... I love her with all my heart."
Sacra, 51, is a married physician from Holden, Massachusetts. He was not directly treating Ebola patients in Liberia during this trip, but was delivering babies at a general hospital in Monrovia, Johnson said.
The doctor started to show symptoms of haemorrhagic fever on Friday evening. Health care workers did an Ebola test on Monday, which came back positive for the deadly virus.
Sacra was following all protocols and taking all necessary precautions against Ebola, Johnson said. It is unclear how he became infected, but SIM is working with the CDC to determine the point of contact.
When asked if the organization was going to bring Sacra back to the United States for treatment, Johnson said all options were being explored.
Sacra is not likely to receive ZMapp, the experimental drug given to Writebol and Brantly, as there are no more doses available. But with supportive care, the doctor could very well recover. While Ebola can be deadly in up to 90% of cases, about half the people in this current outbreak have survived.
There were mornings in Liberia, as Writebol fought off the deadly Ebola virus, when she woke up and thought with surprise, "I'm alive."
Writebol was diagnosed on July 25. She originally thought she had malaria, she said, and took medication to fight off the mosquito-borne disease. But even after the round of medication was completed, the symptoms persisted.
A doctor took a blood sample for an Ebola test "just to make sure" and it came back positive. When she found out, Writebol told her husband it was going to be OK. But "I had no clue what was going to happen," she said.
Writebol and Brantly were flown from Liberia to be treated at Emory University Hospital in Atlanta in early August.
As she was being boarded onto the plane, she thought, "I don't even know if I'm going to make it to the U.S." She said she remembers little else about the moments before the flight, other than a doctor in protective clothing putting his hands around her face and saying, "Nancy, you're going home."
At Emory, Writebol was still in pain -- unable to move her legs or feet. But one day, she said, she pushed herself to get out of bed and take a shower. From that point on, doctors saw small signs of progress.
Writebol and Brantly were released from the Atlanta hospital two weeks ago, just days apart.
When asked what she thinks may have saved her -- The experimental drug? The dedicated health care workers in Liberia and Atlanta? Her faith? -- Writebol answered, "All of the above."
Writebol, whose missionary work includes 14 years of aiding orphans and vulnerable children in Africa, was in Liberia with the aid organization Serving in Mission. She and her husband arrived there in August 2013.
She guided missionaries and teams and worked with nurses at ELWA hospital in the capital of Monrovia, where her husband is the technical services manager, according to the Christian group's website.
The fact that the Writebols left the comforts of America to live in an area rife with poverty, instability and disease, and put their lives at risk to assist those suffering everyday, doesn't surprise those who know them.
John Munro, their friend and pastor at Calvary Church in Charlotte, described the couple as "the salt of the Earth," the kind of people who wouldn't give a second thought to dropping everything to help.
The only thing perhaps ironic about what's happening now is how such an "unassuming" and "very humble" woman has become international news.
"She is ... not someone who would ever make the headlines," Munro said, "apart from something like this."
Married for 40 years, the Writebols have traveled the globe, focused on their faith and their desire to help others. Wherever they've gone, their lives have been centered on their church and their family, including two now-adult sons who live in the United States.
Ebola might have derailed them, but it hasn't changed their purpose in life.
"We aren't going to stop our ministry," David Writebol said last month. "We believe we can serve wherever God sends us."
For now, the couple is going to enjoy spending time with their children and grandchildren. Writebol said she "can't wait" to put her arms around her family.
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