BOCA RATON – The presence of anthrax has been detected in the nasal passage of a co-worker of the man who died last week from anthrax, health officials said Monday. The building where both worked was closed after the bacterium was detected there.

In the latest case, a man whose name was not immediately made public was in stable condition Monday at an unidentified hospital, according to both the Florida and North Carolina health departments.

A nasal swab from the patient tested positive for the anthrax bacterium, said Tim O’Conner, regional spokesman for Florida’s health department.

“(Doctors) describe his condition as good right now. He hasn’t been diagnosed with the disease, there’s just a presence of (the disease) in his nostrils,” O’Conner said.

It was not yet clear if anthrax had only infiltrated his nose, spread to his lungs or if he had a full-blown case of the disease.

“We have someone who has been exposed to bacillus anthracis, which is the spore which inhaled in a large enough dose could cause anthrax illness,” said Barbara Reynolds, a spokeswoman for the U.S. Centers for Disease Control and Prevention in Atlanta. She said he is undergoing tests to determine whether he has a full-blown case of anthrax.O’Conner and Reynolds said they did not know the symptoms displayed by the man, where he was hospitalized or when the swab was taken.

The man’s co-worker, Bob Stevens, died on Friday, the first person in 25 years in the United States to have died from a rare inhaled form of anthrax.

O’Conner said the man now hospitalized worked in the same building as Stevens. He did not know whether they worked together or had come into contact with each other.News that Stevens had contracted the disease set off fears of bio-terrorism, especially when it was revealed that Middle Eastern men were believed to have recently visited an airfield about 40 miles from Stevens’ home in Lantana and asked questions about crop-dusters.

O’Conner said there is no evidence that either man was a victim of terrorism.

“That would take a turn in the investigation,” he said. “It’s a different aspect, we were thinking more of environmental sources.”Stevens, 63, was a photo editor at the supermarket tabloid The Sun. Environmental tests performed at The Sun’s offices in Boca Raton detected the anthrax bacteria, O’Conner said.

The Sun’s offices have been shuttered and law enforcement, local and state health and CDC officials were to take additional samples from the building on Monday, O’Conner said.

Some of the other environmental samples taken last week are still being tested, Reynolds said.

She would not say just where the sample that tested positive for the bacteria was found.

About 300 people who work in the building were being contacted by The Sun and told not come to work Monday. Each of the workers will undergo antibiotic treatment to prevent the disease and have nasal swabs taken, Reynolds said.

The FBI was helping in the search for the source of the bacterium, said Miami FBI spokeswoman Judy Orihuela. But “the current risk of anthrax is extremely low,” O’Conner said.

It was unclear when the final tests would tell whether the second man has full-blown anthrax. The bacterium normally has an incubation period of up to seven days, but could take up to 60 days to develop, O’Conner said.

“We’re waiting for additional testing to see if it will become a confirmed case of anthrax or not,” said Reynolds of the CDC.

“I realize for the public this is going to be a very slight distinction.”

Michael Kahane, vice president and general counsel of American Media Inc., which publishes The Sun and two other tabloids, The Globe and the 0, confirmed the company closed its Boca Raton building at the request of state health officials.