MADRID?- Health officials say two doctors who treated a Spanish nursing assistant diagnosed with Ebola have been admitted to a Madrid hospital for precautionary observation, bringing to six the number being monitored at the center.

A spokeswoman for the Carlos III hospital said Thursday neither of the doctors, nor the woman's husband _ who is also under observation _ has shown Ebola symptoms.

The doctors tended the nurse, Teresa Romero, before she was diagnosed as having Ebola on Monday.

Two other nurses in quarantine are awaiting tests for the virus.

Romero is the first person known to have caught the disease outside the outbreak zone in West Africa. She is in stable condition without fever.

The official spoke on condition of anonymity in keeping with hospital regulations.

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