Protecting families from contaminated food and water
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Protecting families from contaminated food and water
Posted in Legionella,Our Blog,Outbreaks & Recalls on September 7, 2025
The Iowa Department of Health and Human Services (Iowa HHS) has identified a cluster of illnesses attributed to Legionnaires’ disease in Marshalltown, Iowa.
What is causing these illnesses? What should you do if you get sick?
Here’s what we know so far about the deadly Legionnaires’ disease in Marshalltown situation.
Last week Iowa HHS announced they are investigating a cluster of Legionnaires’ disease cases. Those who are sick live in north central Marshalltown.
So far 21 people have been diagnosed with Legionnaires’ disease in the area. One person has died.
At this time, Iowa HHS does not believe the illnesses are linked to the public water supply.
Zach Maxfield, general manager of Marshalltown Water Works explains that the town’s treated water is not the likely source of this Legionnaires’ disease outbreak.
“There’s no indication that it’s Marshalltown drinking water that is the cause of this.”
According to Maxfield, the water plant rigorously tests for all bacterial pathogens. The bacterial contamination, he says, is more likely to come from building plumbing systems or appliances. Things like air conditioners, boilers, and water heaters.
The water may come from the water treatment plant. But then it goes through the distribution network.
“[The water] goes into your house, goes into an apartment, goes into a business, and it reacts with your hot water heater, boilers, air conditioning units, goes through your sprinkler head, and that’s where that bacteria is living. If it turns into a mist or aerates, that’s when Legionnaires’ disease can happen.”
So far, more than 20 people have become sick with Legionnaires’ disease in Marshalltown. At least one person has died so far. Without a known source, more are likely to follow.
But what is Legionnaires’ disease anyway, how do you get it, and how bad is it?
Legionnaires’ disease is caused by inhaling microscopic Legionella bacteria.
While these bacteria are naturally occurring is fresh water sources (lakes, streams, rivers, etc.), it becomes a big problem when they make their way into building water systems.
If these bacteria are allowed to grow, people can become sick. Some may die.
According to the Center for Disease Control and Prevention (CDC), 1 in 20 people exposed to Legionella bacteria will become sick. Rates of illness are high. And so is mortality rate. An unfortunate 1 in 10 will die from their infection.
Cooling towers are a significant source of Legionnaires’ disease. But there are other sources.
There are several common sources of Legionnaires’ disease. A small amount of Legionella bacterial contamination can grow into a huge problem. When that bacteria can become a mist, people can breathe in those tiny droplets containing those germs.
Some of the common sources of Legionella bacteria include:
Not everyone who is exposed to Legionella bacteria will become sick. Most normally healthy individuals will not become infected. However, certain groups of people are at higher risk of infection if exposed.
Higher risk groups include:
While Iowa HHS explains that the risk of Legionnaires’ disease is low, those who live, work, or visit the area who become sick with pneumonia-like illness should visit their primary care doctor and discus this advisory.
Iowa HHS has issued communication to health care providers in the area notifying them of the recent illnesses as well as advising them to consider testing for Legionnaires’ disease in patients with those symptoms.
Those who spend a significant amount of time in the area who begin to develop symptoms should seek medical attention right away.
Legionnaires’ disease can be deadly. But it is also treatable, with better outcomes if treatment is administered early.
“Iowans should know that Legionnaires’ disease can be effectively treated with antibiotics if diagnosed early. Adults aged 50 or older, those who smoke or individuals with chronic lung conditions should seek medical care promptly if they develop flu-like or respiratory symptoms,” said Dr. Robert Kruse, Medical Director at Iowa HHS.
While symptoms and severity can vary from person to person, symptoms may include:
Other Symptoms may include:
Most people begin feeling sick between two and 14 days after exposure. However, it can take longer for symptoms to appear in some cases.
While the investigation on a potential source of this outbreak of Legionnaires’ disease in Marshalltown is ongoing, Iowa HHS has asked businesses and property owners to help. Especially those with cooling towers, hot tubs, or fountains.
The following recommendations have been announced:
If you become sick with pneumonia or flu-like symptoms after visiting or staying in the Marshalltown area, you may have Legionnaires’ disease.
If you have become sick with pneumonia-like illness, seek medical attention immediately.
Legionnaires’ disease can be deadly. Do not wait!
Request a diagnostic test for Legionnaires’ disease. If your healthcare provider does not suggest one, notify them of the potential exposure risk.
If you test positive for this illness, your local health department will be notified following your diagnosis. Someone may contact you about your illness to ask questions that may help narrow down a source.
The source of this outbreak of Legionnaires’ disease in Marshalltown has not yet been discovered.
For this reason, it is important to make a list of the places that you have been in the weeks prior to becoming sick. The earlier that you can make this list, the more complete and accurate it will be. Have it ready in case you are asked for it.
This information is important, in that it could narrow or expand the scope of this Legionnaires’ disease investigation and help prevent further spread of this deadly infection.
If you have become sick from living, working, or visiting the Marshalltown area, you may have questions. An experienced Legionnaires’ disease lawyer understands your situation and can assist you through the complicated legal process.
If you wish to pursue a legal claim for financial compensation to cover medical expenses, lost work, caring for a loved one, or other burdens associated with Legionnaires’ disease illness, The Lange Law Firm, PLLC has a Legionnaires’ disease lawyer that can help.
Call (833) 330-3663 or send us an email for a free, no obligation consultation.
By: Heather Van Tassell (contributing writer, non-lawyer)