Howard County Public Schools began testing cooling towers in Sept. 2019. Out of the 23 schools tested, nine high schools came back positive: Atholton, Long Reach, Hammond, Howard, Marriotts Ridge, Mt. Hebron, and River Hill. Along with those high schools, two elementary schools also tested positive: Laurel Woods and West Friendship.
Every year, Howard County Public School System has mandatory testing before school starts. These include testing the water supplies for toxins, including the Legionella bacteria. It is common to find Legionella in cooling towers and the disease is often found in bodies of freshwater such as lakes and streams.
The presence of Legionella isn’t always dangerous. Out of the 50 types of the bacteria, only 20 actually cause diseases. The Legionella bacteria at Mt Hebron isn’t in the drinking water such as water fountains, or in the sinks, rather, the cooling towers are connected to the HVAC system.
“It is not uncommon to find various Legionella species in building water systems used to cool water as part of the building’s HVAC system,” the Howard County Schools said in a statement on their website. “This is not drinking water or water that is used for any other purpose.”
Exposure to Legionella bacteria can lead to Legionnaires disease, a disease that causes pneumonia-like symptoms including diarrhea, nausea, and confusion. It can also cause a less serious illness called Pontiac fever. Symptoms include coughing, shortness of breath, fever, muscle aches and headaches.
“At first I was kind of freaked out, because I thought, ‘Oh my god, there’s this thing that causes disease in our school,’” said Mt Hebron freshman Natalie Booth. “But then I learned it was in the cooling towers at Hebron, and that it wasn’t at the dangerous threshold yet, so I felt a little better about it, more indifferent.”
Of the nine schools, Atholton, Long Reach, and River Hill were the only schools that had concerning levels of Legionella bacteria in cooling towers that would require interference from the Occupational Safety and Health Administration (OSHA).
Further tests of the water and treatments of the more serious levels are to be
expected, and updates on the situation will be shared with the community. OSHA will have an interference for schools where the Legionella bacteria levels require it.