Health workers have fought the Ebola outbreak to a tentative standstill in Nigeria, Africa’s most populous nation, offering at least a chance to eradicate the disease there before it spins out of control, as it has in Guinea, Liberia and Sierra Leone, where a sluggish response failed to halt it early.

 

Nigeria’s small number of cases — 11 confirmed and one suspected — provides a brief window in which to wipe out Ebola. If these efforts fail, the death toll could be horrific. The cases have occurred in Lagos, a city with 20 million people, many of them jammed into teeming slums where the virus could become unstoppable.

 

Dr. Thomas R. Frieden, the director of the Centers for Disease Control and Prevention, said health officials were watching Nigeria with intense interest, because of its huge population and because it is much more of a crossroads than the other three countries, in much closer touch with the rest of Africa.

 

“We’re waiting for the other shoe to drop,” he said.

 

The World Health Organization said on Thursday that staff members on the front lines of the outbreak across the region had warned that the nearly 2,000 reported cases and the more than 1,000 reported deaths “vastly underestimate the magnitude of the outbreak.” And Doctors Without Borders said on Friday that the disease was still spreading faster than the efforts of governments and health workers to keep up with it, calling ground conditions “like a war.”

 

About 200 people who had contact with the infected patients in Lagos are receiving daily visits from health workers for 21 days, the incubation period of the disease, to check for fever or other symptoms, said David Daigle, a spokesman for the team in Nigeria from the Centers for Disease Control and Prevention. So far, 61 have finished the follow-up and are in the clear, he said. About 60 Nigerian health workers have been trained to trace contacts, and more are being taught, to bring the total to 200, Mr. Daigle said.

 

Ebola arrived in Nigeria on July 20, carried by Patrick Sawyer, a native Liberian and naturalized American citizen. He contracted the disease in Liberia, flew to Lagos while he was ill and died on July 25. Health officials say he was vomiting during the flight.

 

Every case in Nigeria has been traced to him. Some victims had helped him when he arrived at the airport, and others were health workers who had treated him without gloves or other protection because they did not realize he had Ebola. President Goodluck Jonathan has been widely quoted in Nigerian newspapers as calling Mr. Sawyer “a madman.”

 

Four Nigerian patients have died, and the mood among the rest is somber, said Dr. Maurizio Barbeschi, a scientist from the World Health Organization who is working on the outbreak.

 

“They think it is a death sentence,” he said. But he said they were getting good care, and he doubted that their death rate would reach that of the other countries, where about 60 percent of the cases have been fatal in some locations.

 

Patients who are health workers are caring for others, helping with tasks like changing bags of intravenous medicines.

 

Last Saturday, Dr. Barbeschi said, he stepped outside the ward where patients are being treated and asked if anyone had a book so he could read to the patients. Mr. Daigle pulled a beat-up copy of Shakespeare’s “Henry IV” from his backpack.

 

Back inside, speaking through a surgical mask, Dr. Barbeschi acted out scenes from the play for a patient fighting for his life.

 

Nigeria has some advantages over other West African countries in dealing with the disease: It has a better health system, and it was on alert for Ebola because the illness had struck the other nations first. Doctors detected it there before a large number of people fell ill. Dr. Frieden said that it took too long to isolate the first person infected from contact, but that the ability to respond had improved tremendously.

 

But Lagos is a huge city. The outbreaks in the other countries have mostly struck villages and towns.

 

“An Ebola outbreak in a dense urban setting is very different from what we know already,” said Dr. Benjamin J. Park, an infection control specialist from the C.D.C. who is working on the outbreak in Lagos.

 

Health officials are using social media, among other channels, to get information to health workers in Lagos — a difficult task because the city has thousands of health facilities, including clinics and small hospitals, Dr. Park said.

 

Dr. Park has been training health workers in how to protect themselves around potentially infected patients. Everyone wants the white Tyvek suits that have been widely photographed, he said, but he tries to convince them that because the disease is spread only by bodily fluids, the suits are needed only when patients are very ill with symptoms like vomiting and diarrhea.

 

If used, they must be removed carefully to avoid contact with secretions that may have splashed on the outside. “I say: ‘Imagine that you’re covered with paint or mud. How are you going to take this off without getting any on your skin?’ ” Dr. Park said.

 

Recruiting health professionals to fight Ebola there has proved challenging. On Wednesday in Lagos, a Nigerian doctor who answered a government call said he was not very worried about the risks. But he declined to give his name because he feared reprisals from the state authorities for talking to the news media, and he said he worried that he would be stigmatized if others learned that he was involved with Ebola. Though the government was offering the equivalent of $185 a day, a substantial sum in Nigeria, only a dozen or so people answered the call that day.

 

A nurse who did respond said he hoped to work on the outbreak by day and continue his regular job at a private hospital by night. He also requested anonymity, for the same reasons as the doctor. Working at the private hospital was riskier than working on the outbreak , he said.

 

“Here, you already know the risk you are facing, but back at the hospital, it’s dangerous because you can’t treat every patient as an Ebola risk,” the nurse said. While working on the outbreak, he would at least be given training and kits with protective gear.

 

But he added, holding a Bible, “It’s God that protects, not the kits.”

 

By DENISE GRADYAUG.

NyTimes

 

Ben Ezeamalu contributed reporting from Lagos, Nigeria, and Nick Cumming-Bruce from Geneva.