(Radio Iowa) – Sixty-eight cases of Legionnaires’ disease are now confirmed in Marshall County, including one death, and the exact cause has yet to be pinpointed, even after two weeks. Marshall County Public Health director Sydney Grewell says they’ve tested a dozen cooling towers in Marshalltown and they’ve all been remediated. Grewell says the test they’re running is called an environmental sample. “The environmental samples do take a long time to grow and Legionella itself is just a hard bacteria to grow in general, so we haven’t found our smoking gun yet,” Grewell says, “but all of those remediated towers, everybody’s been working well with us and helping stop the spread of Legionella.”

When Grewell became the county’s public health director, she didn’t know she’d be learning so much about cooling towers, and she explains what they are. “Cooling towers are basically a large air conditioning system. These cooling towers are for large entities, just places that might need more air, and they’re used with a water-based system and it circulates and then it blows water into the air, which is how we get that legionella,” Grewell says, “and then it spreads around.” Grewell says they’re almost certain a cooling tower on the north side of Marshalltown is the culprit.

“We are focusing on the cooling towers and the CDC is in line with that,” Grewell says. “People like to go down those rabbit holes of like, ‘Well, what if it’s not that?’ Most of the time it is that cooling tower and that’s what we’re really focused on because of what we’re seeing.” As people begin to break out their humidifiers for the winter season ahead, she suggests they give the devices a good cleaning before use. Grewell says it takes between two and 14 days for people to start showing symptoms of Legionnaires’ disease, a lung infection that’s a form of pneumonia.”The most common ones, the dry cough, a high fever like 102, 103, 104, nothing to mess around with,” Grewell says. “It’s not just like, ‘Oh, we’re at 99,’ it’s high, sometimes weakness, fatigue.”

Other symptoms might include chills, muscle aches, headaches, and diarrhea. Grewell says if you are showing any of these symptoms, contact your primary healthcare provider and get tested.