MONROVIA, Liberia — One of Liberia’s highest profile doctors has died of Ebola, officials said Sunday, and an American physician was being treated for the deadly virus, highlighting the risks facing health workers trying to combat an outbreak that has killed more than 670 people in West Africa, the largest ever recorded.

A second American, a missionary working in the Liberian capital, was also taken ill and was being treated in isolation there, said the pastor of a North Carolina church that sponsored her work.

Dr. Samuel Brisbane was treating Ebola patients at the country’s largest hospital, 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.


The American, 33-year-old Dr. Kent Brantly, was in Liberia helping to respond to the outbreak that has killed 129 people nationwide when he fell ill, according to the North Carolina-based medical charity, Samantha’s Purse.

Brantly, from Fort Worth, Texas, is the medical director of the aid group. He is in stable condition, receiving intensive care in a Monrovia hospital, according to a spokeswoman for the aid group, Melissa Strickland.

‘‘We are hopeful, but he is certainly not out of the woods yet,’’ she said.

Early treatment improves a patient’s chances of survival, and Strickland said Brantly recognized his symptoms and began receiving care immediately.

There is no known cure for the highly contagious virus, which is one of the world’s deadliest. At least 1,201 people have been infected in Liberia, Sierra Leone, and Guinea, according to the World Health Organization, and 672 have died, not including a death in Nigeria reported last week.

Besides the Liberian fatalities, 319 people have died in Guinea and 224 in Sierra Leone.The Nigerian death was the first in that country. Nigerian authorities said Friday that a Liberian man died of Ebola after flying from Monrovia to Lagos via Lome, Togo.


The Nigerian 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. The disease escalates to vomiting, diarrhea, and internal and external bleeding.

Health workers are among those at greatest risk of contracting the disease, which spreads through contact with bodily fluids. The WHO says the disease is not contagious until a person begins to show symptoms.

Besides Brantly and the two doctors in Liberia, Sierra Leone’s top Ebola doctor and a doctor in Liberia’s central Bong County have also fallen ill.

Brantly’s wife and children had been living with him in Liberia but flew home to the United States about a week ago, before the doctor started showing any signs of illness, Strickland said.