PARIS - French health officials said Friday they are investigating three suspected cases of a deadly new respiratory virus related to SARS, in people who had close contact in the hospital with France’s only confirmed case.

Beatrice Degrugillers, a spokesman for the regional health agency in France’s Nord-Pas-de-Calais region, said a nurse at the hospital where the man was hospitalized in late April has been under watch at the hospital in Douai since Thursday night.

A doctor and a former hospital roommate who had each been in contact with the first patient also remain hospitalized.

If confirmed, the additional cases would heighten concerns about the virus’ ability to spread easily between people. Health authorities have previously said the new corona virus has spread in limited circumstances between people in very close contact, such as relatives taking care of family members.

In 2003, the spread of SARS in hospitals in Asia ultimately sparked a global outbreak. Officials consider any spread of a new virus in hospitals to be the first sign it is gaining the ability to infect humans easily.

On Wednesday, authorities announced the 65-year-old Frenchman was France’s first confirmed case of the corona virus, which has killed 18 people since being identified last year in the Middle East.

The patient fell ill after returning from a nine-day vacation in Dubai in the United Arab Emirates as part of a package tour, the Health Ministry said.

The man, whose identity was not released, returned from Dubai on April 17. He was hospitalized with respiratory problems in the northern French city of Valenciennes on April 23, and transferred to a more advanced facility in Douai on April 29.

Front Section, Pages 10 on 05/11/2013