A Spanish nurse who is the first person to have contracted Ebola outside of West Africa is being treated with a drip of antibodies from patients previously infected with the virus, according to Reuters. The nurse helped treat two Spanish priests who had contracted Ebola in Africa and was diagnosed with the deadly disease on Monday.

Authorities have hospitalized and are monitoring three people, including the nurse’s husband, who were in close contact with the nurse for signs of infection, Spanish health officials said. Another health worker and a traveler who spent time in West Africa were among the three people who were hospitalized.

The 44-year-old Spanish nurse, whose name has not been released, is married with no children. She was part of a team that treated a Spanish missionary and a Spanish priest, both of whom died after returning to Spain with Ebola. The nurse reportedly went on vacation after the second priest she was caring for died on Sept. 25. She began showing symptoms of Ebola five days later.

Her infection has raised doubts about whether appropriate measures were taken to contain the virus and keep health workers healthy. “Something went wrong,” Máximo González Jurado, head of Spain’s General Nursing Council, told Spanish news agency EFE. “They need to establish if the protocol is correct or not correct so that a case like this, that never should have happened, doesn’t happen again.”

The U.S. is the only other country outside of Africa to report a case of Ebola. Thomas Eric Duncan, a Liberian national who had flown to the U.S. to marry his girlfriend, was diagnosed with Ebola in Dallas last week and is in critical condition. He is being treated with a medication called brincidofovir, according to officials from the hospital where Duncan is receiving treatment.