A doctor, originally from the U.S., is in stable condition after being infected by and treated for the Ebola virus while working in Liberia.

The latest outbreak in western Africa has claimed nearly 700 people in more than four countries, according to the Daily Mail. The survival rate is 10 percent.

One of those was a chief medical doctor at a hospital in Libera, Dr. Samuel Brisbane, who died on Saturday. Another doctor from Uganda died earlier this month, according to The Associated Press.

Dr. Kent Brantly, who is originally from Texas, moved to Liberia before the outbreak.

He is working for a North Carolina-based Christian international aid organization, Samaritan's Purse, and helping to battle the outbreak by treating patients.

Brantly received intensive treatment and is in stable condition, as of Sunday, but he is still under observation.

His family had been living with him, but they are now all back in the U.S.

One of the latest confirmed cases of Ebola was a businessman who arrived by plane to Nigeria, according to the Daily Mail. The ease of transfer on airplanes for the highly contagious virus has spurred airport securities to screen passengers for symptoms who are arriving from foreign countries.

Dr. Lance Plyler, who leads the ebola medical efforts in Liberia that Brantly was part of, said screening passengers may help slow the spread, but could not prevent it, according to the Daily Mail.

"Unfortunately the initial signs of ebola imitate other diseases, like malaria or typhoid," he said.

The virus has an incubation period of up to three weeks and cannot be immediately diagnosed.

Airports in Guinea, Liberia and Sierra Leone -- the countries with the highest number of outbreak cases -- have implemented measure to help prevent the spread but experts warn they may not help.