Spanish nurse Teresa Romero, who became the first person to contract Ebola outside West Africa, has now tested negative for the virus, the Spanish government says.

The result suggests Teresa Romero, 44, is no longer infected – although a second test is required before she can be declared free of Ebola.

Teresa Romero contracted the virus when treating two infected patients in a Madrid hospital earlier this month.

The Ebola outbreak has killed more than 4,500 people across West Africa.

Spanish nurse Teresa Romero became the first person to contract Ebola outside West Africa

Teresa Romero tested positive for the virus on October 6, after she treated two missionaries who had been repatriated from West Africa. The missionaries later died from the virus.

The nurse has said she might have become infected when she removed her protective suit.

A doctor in Madrid said Teresa Romero may have touched her face with her gloves after treating one of the missionaries.

Teresa Romero has been treated at Carlos III hospital in Madrid, and was reportedly given a human serum containing antibodies from Ebola survivors.

A government statement on October 19 said that a blood test appeared to show that the virus was no longer in her body.

She would be given a second test overnight, the statement said, adding that her health was “developing favorably”.

Fifteen other people, including Teresa Romero’s husband, remain under observation in quarantine, but have not shown any symptoms so far, the hospital said.

The incubation period for Ebola can last from two days to three weeks.

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