NEW YORK (Reuters) - A New York City hospital is running Ebola tests on a doctor who returned to the United States from West Africa with a fever and gastrointestinal symptoms, the city's Health Department said on Thursday.

Preliminary test results were expected in the next 12 hours, the New York City Department of Health and Mental Hygiene said in a statement.

The patient, identified as Dr Craig Spencer of Harlem is being treated at Bellevue Hospital.

The statement said he returned to the United States within the past 21 days from one of the three African countries facing the Ebola outbreak.

Dr Spencer, who worked with Doctors without Borders, reported his fever immediately, and Doctors Without Borders said it promptly notified the city health department.

New York Mayor Bill de Blasio said: "Our understanding is that very few people were in direct contact with him."

Dr Spencer's Facebook page showed a photo of him clad in protective gear. It shows he went to Guinea around Sept 18 and then to Brussels on Oct 16.

Dr Spencer has been a fellow of international emergency medicine at Columbia University-New York Presbyterian Hospital min New York City since 2011, according to his profile on the LinkedIn career website.

Columbia did not respond to a request for comment.

He described himself on LinkedIn as fluent in Chinese, French and Spanish.

A woman at the Bellevue Hospital information desk identified herself to a staff member as the patient's fianceé. She appeared very agitated and declined to comment.

The health department said it was tracing all of the patient's contacts to identify anyone who may be at potential risk.

It said the patient had been transported by a specially trained unit wearing protective gear.