A nurse's story: On the front lines of Ebola outbreak

When Doctors Without Borders nurse Monia Sayah first arrived in Guinea in March, she couldn't have known she would witness the worst Ebola outbreak in history. Back then, there were 59 confirmed deaths from Ebola, a virus which can be fatal in up to 90 percent of cases. The death toll in West Africa has since soared to 932, the World Health Organization said Wednesday. In Guinea, where the first cases were reported in March, Ebola has killed 363 people.

"The fear is palpable," Sayah said, speaking to CBS News in New York after returning from her latest assignment. "People are very afraid because they never know if Ebola's going to hit their family or their village."

Because of the fear and stigma associated with the virus, Sayah said many infected people are choosing to hide their illness and often don't check in to treatment centers until it is too late. By that point, there is very little Sayah and her colleagues can do. They try to rehydrate the patients and administer antibiotics. But there is no proven treatment for Ebola, though an experimental drug is currently being tested.

Concerns have also been growing for the safety of medical workers in the field. A leading doctor died in Sierra Leone last week. A Nigerian nurse who treated that country's first Ebola victim died from the virus, Nigerian health officials said Wednesday, and two American medical missionaries infected with Ebola in Liberia are still battling the virus at Emory University Hospital in Atlanta.

But Sayah, who has spent a total of 11 weeks in Guinea, said she is not afraid. She and her colleagues take strict precautions to limit their risk of exposure. Before entering a high-risk zone, they suit up in head-to-toe protective clothing including gloves and goggles. "You do have to follow the rules," she said, "but accidents do happen."

She has to limit the amount of time she spends in the infected area. It's hot under the protective clothing, and exhaustion and dehydration are serious concerns. "The risk is you could faint, you could fall. You do not want to fall in a high-risk area," she said. "Maybe your goggles will move up and your eye will be infected."

Working so closely with patients at death's door has taken a personal toll. Sayah described the anguish of stepping outside a treatment facility to take a quick break from the intense heat, only to find that her patient had died in those ten minutes she was away. "It was really hard for me to know that they had died alone," she said, "not with someone holding their hands and reassuring them."

Sayah recalled the "hectic" challenges of setting up some of the first international treatment facilities for Ebola patients. By the end of May, she said, the medical community thought they had almost contained the virus. But soon after she left Guinea, another cluster of infected patients was found in another village. The virus was spreading like wildfire.

Several factors are contributing to the spread. The virus has an incubation period of up to 21 days, according to the WHO, and in West Africa the population is highly mobile, moving easily across porous cross-country borders. Traditional burial ceremonies in which relatives have direct contact with the body can also play a role in the transmission of Ebola.

Sayah found that many local communities distrust the healthcare system and foreigners. "Some have said we brought the Ebola to them," she said. "It's very difficult to contain the outbreak when communities are not cooperating." There were instances of infectious patients leaving the facility, she said, and many weren't receptive to the idea of isolation -- a crucial step in containing the virus.

During her breaks from the field, Sayah stays in touch with her colleagues on the front lines, hoping for the slightest bit of good news. Just this past week, she heard some. One of the patients who'd been under her care was discharged from hospital, apparently free of the virus.

But the situation on the ground remains dire, and Sayah hopes to see a greater response from the international community.

Despite the challenges, Sayah said she will return to West Africa to fight the outbreak. "When you're there and you see how much needs to be done," she said, "there is not a question of 'should I go back or not?'"