Nigeria's commercial capital Lagos has 10 confirmed cases of Ebola, up from seven at the last count, and two patients have died, including the Liberian who brought the virus in, the health minister has revealed.
All were people who had had direct contact with Patrick Sawyer, who collapsed on arrival at Lagos airport on July 25 and later died, Health Minister Onyebuchi Chukwu said.
A nurse who had treated Sawyer without knowing what he had and did not therefore wear protective gear, also died.
Nigeria on Friday declared a national emergency over the Ebola outbreak.
"As at today, 77 primary and secondary contacts of the index case have been placed under surveillance or isolation," Chukwu told a news conference. The latest case was also a nurse, who had had primary contact with Sawyer, a Liberian-American.
"When she got ill, we then brought her into isolation. We just tested her over the weekend."
She had been at home with her husband, who was also now under surveillance, Chukwu said.
The West African Ebola outbreak is the worst in history and the World Health Organisation (WHO) said on Friday it represented an international health emergency that will likely continue spreading for months. It said 961 people had died so far during the outbreak and 1779 had been infected.
Sawyer has faced fierce criticism for travelling to Nigeria despite being ill and being under surveillance by Liberian authorities because his sister had died of Ebola.
"It is unfortunate that one mad man brought Ebola to us, but we have to contain it," Nigerian President Goodluck Jonathan said yesterday.
"As a government we promise we will do everything possible to contain Ebola."
The disease has strained health systems of affected states and governments have responded with measures including national emergencies declared in Sierra Leone, Liberia and Nigeria.
Nigeria faces the added problem that public sector doctors are on strike over pay and conditions, and have resisted calls by the government to return to work to tackle the Ebola crisis.
Chukwu announced a series of measures meant to contain the disease, including training health care professionals of surveillance of possible cases, putting port officials on red alert, a public awareness campaign in multiple languages and alerting hospitals to set up isolation wards.
The Nigerian Red Cross said it had provided 18 volunteers to work with the authorities to educate people on how Ebola spreads.
Ebola is one of the world's most deadly diseases, with no known vaccine or cure. The Zaire strain - the one currently spreading through West Africa - can kill up to 90 percent of sufferers, although in the latest outbreak the death toll has been around 55 percent.
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