Tess Owen | VICE News | August 12, 2015

The massive pharmaceutical company GlaxoSmithKline (GSK) had to temporarily shutter its North Carolina factory -— which produces medications for respiratory conditions —after Legionella bacteria was detected in one of the plant’s cooling towers this week.

The factory, which is located in Zebulon, North Carolina, reportedly handles more than 30 brands, including Combivir, which treats HIV, the antidepressant Wellbutrin, and Zofran, which is used to prevent chemotherapy induced nausea. Respiratory drugs that the plant produces are Advair, Breo, and Ellipta, all of which come in the form of an inhaler and are prescribed to people with asthma and chronic lung diseases. Advair is the largest product line at the Zebulon plant.

Legionella bacteria tends to thrive in warm water — and is often found in hot tubs, extensive plumbing systems, decorative fountains, or cooling towers. To become infected, a person has to be exposed to the mist or vapor containing the bacteria — it can’t spread from one person to another.

GSK representative Marti Skold Jordan told VICE News on Wednesday that “the cooling tower is a standalone structure which does not come into contact with product manufactured at the facility.”

Jordan also said that all employees working at the facility had been sent home and the cooling towers will be fully cleaned and retested before the factory reopened.

GSK’s detection of the bacteria coincides with a recent outbreak of Legionnaire’s disease in the South Bronx, which has so far killed 12 and infected over 100.

The incubation period for the Legionella bacteria usually lasts between two and 10 days, but people can still begin exhibiting symptoms around two weeks after exposure. A report from the New York City’s Department of Health and Hygiene says that all 12 people who died had existing medical problems, which Legionnaire’s complicated.

Janet Stout, director of the Special Pathogens Lab in Pittsburgh, told VICE News that she thought GSK’s decision to close the factory was overly cautious. Many cooling towers will test positive for traces of Legionella bacteria, Stout says, but those traces won’t necessarily lead to an outbreak of Legionnaire’s disease.

“You just need to adjust your water treatment program to get those numbers [Legionella bacteria] down,” she said.

“People get very anxious when an outbreak occurs,” she added while commenting on the Bronx outbreak. “But when you look at all the people who are exposed to the bacteria, only 2-5 percent become infected.”