RALEIGH, N.C. » Drugmaker GlaxoSmithKline shut down a plant Tuesday that produces inhaled medications after discovering the bacteria that causes Legionnaire’s disease, a potentially fatal form of pneumonia.

The manufacturing plant in Zebulon, about 25 miles east of Raleigh, was closed after routine testing found the bacteria in cooling towers. About 400 of the 850 employees who work in Zebulon were told to stay away until the towers are cleaned, officials for the London-based company said.

It was not immediately clear whether there was any effect on medications produced at the site.

"We are trying to gather information on what the situation is," spokeswoman Jenni Brewer Ligday said. "It was found during routing testing, so we’re trying to get a better handle of how often those testings are conducted. Also more details on whether product has been impacted and, if they have, what is our procedure in place to handle that."

The plant produces inhaled drugs like Advair, a drug for asthma, and contracts with other pharmaceutical companies to produce their drugs.

The Food and Drug Administration was checking into reports of the bacteria’s discovery and a spokesman had no immediate comment.

State and county health officials said they were not aware of any Legionnaire’s disease cases associated with the Glaxo facility, adding that most people who are exposed to the bacteria do not become ill.

The same bacteria found in cooling tanks in the Bronx section of New York City caused 12 Legionnaires’ disease deaths this summer. The Centers for Disease Control and Prevention says about 8,000 to 18,000 Americans are hospitalized with the illness annually.

People can contract Legionnaires’ disease when they inhale water vapor or mist containing the bacteria, the CDC said. It does not spread from person to person, the agency said.