MADRID--The Spanish nursing aide who became the first person infected with Ebola outside West Africa was declared cured of the illness Tuesday.

Officials at the hospital where Teresa Romero was being treated said she had tested negative for the deadly virus for a second time.

Ms. Romero, 44 years old, has been quarantined at Madrid's Carlos III Hospital since being diagnosed with the virus on Oct. 6. She was part of a medical team that had treated two Spanish missionaries brought to the hospital in August and September after contracting Ebola in Africa. Both missionaries died.

Fifteen people whose close contact with Ms. Romero put them at risk have been isolated at the hospital for observation but show no symptoms of Ebola, officials have said.

Write to Jeannette Neumann at jeannette.neumann@wsj.com

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