Health officials confirmed on Monday that a Spanish nurse, who treated a priest repatriated with Ebola last month, has contracted the virus. (Reuters)

In the first known case of Ebola transmission outside of Africa, a nurse in Spain has contracted the deadly virus after caring for a sick priest who had been flown back from West Africa for treatment, Spanish health minister Ana Mato said at a news conference Monday.

Two tests confirmed the diagnosis of the woman, Mato said. She was part of a medical team treating Manuel Garcia Viejo, the priest who died Sept. 25 of Ebola, according to the BBC.

The infected health worker's only symptom so far is a fever, and her condition remains stable, Mato said. Authorities are trying to determine how exactly she contracted Ebola and whether the team caring for the priest observed proper medical protocols, Mato added.

Ebola is spread through direct contact with the bodily fluids of an infected person exhibiting symptoms.

Authorities are already trying to trace all of the people the health-care worker may have had contact with, said Madrid's primary health-care director Antonio Alemany, according to the Associated Press. The 30 health care workers who came into contact with her will be under a 21-day period of monitoring, the incubation period for the disease to take hold, NBC news reported.

The nurse worked as a sanitary technician, entering the priest's room once to treat him and one other time to collect his belongings, according to NBC News. She began showing symptoms Sept. 30 and went to a Madrid-area hospital Sunday, AP reported.

There have been more than 7,400 confirmed, suspected and probable cases of Ebola in Guinea, Liberia and Sierra Leone, according to World Health Organization figures released Friday. The death toll in the deadliest Ebola outbreak in history has surpassed 3,400.

According to the WHO, "exposure of health-care workers ... continues to be an alarming feature of this outbreak." As of Oct. 1, the WHO said, 382 health-care workers have been infected by Ebola in West Africa; 216 of them have died.

[This post originally reported the wrong day of the nurse's hospitalization. It has been corrected and updated.]

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