A Spanish nurse, who is the first known person to have contracted ebola outside West Africa, is reportedly no longer infected with the deadly virus.
Teresa Romero, 44 had treated two patients, who died of the disease at a hospital in Madrid, before contracting the virus herself.
She tested positive for ebola on October 6 and was placed in quarantine. Today, a blood test showed no sign of the virus. A second blood test will be conducted to confrim that she is free of the disease.
The news comes as British ebola survivor Will Pooley flew back to West Africa, pledging to continue the effort to contain the epidemic.
The 29-year-old nurse from Eyke in Suffolk, was the first confirmed Briton to contract ebola while treating infected patients in a government hospital in Kenema. He returned to the UK in August and was treated with the experimental drug ZMapp at the Royal Free Hospital in London.
Now cured of the deadly disease, he described his decision to return as "something I need to do"
Mr Pooley said he was "delighted" to return to Sierra Leone, and was looking forward to doing all he could "to prevent as many unnecessary deaths as possible".
"I am delighted to be returning to Sierra Leone to join the King's Health Partners team. I would like to once again thank the team at the Royal Free Hospital and the RAF who provided me with such excellent treatment and support. But the real emergency is in West Africa, and the teams out there need all the support we can give them. I am now looking forward to getting back out there and doing all I can to prevent as many unnecessary deaths as possible."
While his family and friends have expressed their concerns at his plans to return to the region, he said they should be reassured by his potential immunity to the virus.
Mr Pooley is due to arrive in the capital Freetown on Sunday night before starting work again on Monday in an Ebola isolation unit run by UK medical staff in Sierra Leone.
He will be working in the isolation unit at Connaught Hospital where he will train local staff and help to set up new isolation units, having previously treated, where he contracted the disease.
Ebola is spread via contact with infected bodily fluids. WHO has assured people that the deadly disease is not airborne, following recent speculation.
Tom Frieden, director of the Centres for Disease Control, warned that unless action is taken, Ebola could become a crisis to rival Aids.
"In the 30 years I've been working in public health, the only thing like this has been Aids," he said at a World Bank and International Monetary Fund annual meeting in Washington
More than 4,500 people have died from ebola, mainly in Guinea, Liberia and Sierra Leone.