A second American in Liberia has tested positive for Ebola, CNN reported, citing the Christian organization she works for.
Nancy Writebol works for Serving in Mission in Liberia and was assisting the SIM/Samaritan's Purse team treating Ebola patients in Liberia's capital city Monrovia, CNN noted, citing a Samaritan's Purse statement.
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Writebol, who serves as SIM's personnel coordinator, has been living in Monrovia with her husband, David, according to SIM's website. The Charlotte, North Carolina, residents have been in Liberia since August 2013, according to the blog Writebols2Liberia. They have two adult children.
Writebol was gravely ill and in isolation in Monrovia, her husband, David, told a church elder via Skype, according to the Rev. John Munro, pastor of Calvary Church in Charlotte, N.C.
Munro said the couple insisted on staying there despite the Ebola threat. "These are real heroes — people who do things quietly behind the scenes, people with a very strong vocation and very strong faith," Munro said.
There is no known cure for the highly contagious virus, which is one of the deadliest in the world. At least 1,201 people have been infected in Liberia, Sierra Leone and Guinea, according to the World Health Organization, and 672 have died. Besides the Liberian fatalities, 319 people have died in Guinea and 224 in Sierra Leone.
Samaritan's Purse announced Saturday that American doctor Kent Brantly had tested positive for Ebola.
Brantly — the medical director for Samaritan Purse's Ebola Consolidated Case Management Center in Monrovia — began feeling ill and then isolated himself as soon as he noticed the symptoms last week, CNN said, citing spokeswoman Melissa Strickland.
Strickland added that Brantly, 33, is in stable condition, talking with his doctors and working on his computer while receiving intensive medical treatment.
She cautions that Brantly is "not out of the woods yet," adding that Ebola patients have a better chance of survival if they receive treatment immediately after being infected, which Brantly did.
Brantly, from Indianapolis, has been working with Samaritan's Purse in Liberia since October 2013 as part of the group's post-residency program for doctors.
And one of Liberia's most high-profile doctors has died of Ebola, officials said. Dr. Samuel Brisbane, a top Liberian health official, was treating Ebola patients at the country's largest hospital, the John F. Kennedy Memorial Medical Center in Monrovia, when he fell ill. He died Saturday, said Tolbert Nyenswah, an assistant health minister. A Ugandan doctor died earlier this month.
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Health officials say the Ebola outbreak, centered in West Africa, is the deadliest ever.
As of July 20, some 1,093 people in Guinea, Sierra Leone and Liberia are thought to have been infected by Ebola since its symptoms were first observed four months ago, according to the World Health Organization.
Testing confirmed the Ebola virus in 786 of those cases; 442 of those people died.
Of the 1,093 confirmed, probable and suspected cases, 660 people have died.
There also are fears the virus could spread to Africa's most populous country, Nigeria.
Ominously, Nigerian authorities said Friday that a Liberian man died of Ebola after flying from Monrovia to Lagos via Lome, Togo. The case underscored the difficulty of preventing Ebola victims from traveling given weak screening systems and the fact that the initial symptoms of the disease — including fever and sore throat — resemble many other illnesses.
Health workers are among those at greatest risk of contracting the disease, which spreads through contact with bodily fluids.
Photos of Brantly working in Liberia show him swathed head-to-toe in white protective coveralls, gloves and a head-and-face mask that he wore for hours a day while treating Ebola patients.
Earlier this year, the American was quoted in a posting about the dangers facing health workers trying to contain the disease. "In past Ebola outbreaks, many of the casualties have been health care workers who contracted the disease through their work caring for infected individuals," he said.
The WHO says the disease is not contagious until a person begins to show symptoms. Brantly's wife and children had been living with him in Liberia but flew home to the U.S. about a week ago, before the doctor started showing any signs of illness, Strickland said.
"They have absolutely shown no symptoms," she said.
A woman who identified herself as Brantly's mother said the family was declining immediate comment when reached by phone in Indiana.
The Associated Press contributed to this story.
This story has been updated.