GlaxoSmithKline has shuttered its drug production plant in North Carolina after bacteria that cause Legionnaire’s disease, a potentially fatal form of pneumonia, were found in a cooling tower.

The bacteria were discovered during a routine inspection of the tower, “a standalone structure, which does not come into contact with product manufactured at the facility,” a GSK spokeswoman confirmed to various media outlets.

A long list of GSK pills are manufactured at the Zebulon site, which houses more than 4,400 staff, including cancer therapy Mekinist (trametinib) and HIV drugs Tivicay (dolutegravir) and Triumeq (abacavir/dolutegravir/lamivudine), as well as inhalers such as Advair (salmeterol/fluticasone) and Ellipta (umeclidinium/vilanterol). The plant will be reopened when further inspections of the tower and cleaning are complete. 

According to local newspaper the Charlotte News and Observer, city and state officials said a public health alert was not warranted and that no threat was posed to city drinking water, but that it was being tested as a precaution.

Elsewhere in the US, an outbreak of Legionnaire’s in the South Bronx area of New York has infected 113 people since last month, claiming 12 lives. Every building in the city with a cooling tower is now being tested for the bug.