T-R PHOTO BY ROBERT MAHARRY Marshall County Public Health Director Sydney Grewell, right, addresses the Board of Supervisors as Supervisor Kevin Goodman, left, looks on during Wednesday morning’s meeting. With no new Legionella cases in over a month, the outbreak is now considered to be over.

Marshall County Public Health Director Sydney Grewell provided her final update to the Board of Supervisors on the recent Legionella outbreak during Wednesday morning’s meeting, noting that there have been no new cases reported for over a month, and all of the 12 businesses with cooling towers in the suspected area of the outbreak have completed the required remediation processes.

Since the outbreak began in late August, a total of 74 cases were reported in Marshall County with two deaths, with the last new case reported on Sept. 25 — about six weeks ago. The outbreak was considered concluded on Oct. 23 when no new cases were reported for 28 days.

“The incident command structure has closed at the state level as well as at the local level,” Grewell said.

Health officials tested each of the 12 suspected cooling towers multiple times in an attempt to find the matching sequence or fingerprint, and one business center did test positive for Legionella pneumophila serogroup 1 (Lp1), the bacteria that causes Legionnaires’ disease, but it did not match the patient who was infected.

“So we still don’t have a smoking gun, and we may never find the smoking gun, unfortunately. But the fact that we found Legionella at all means that we’ve been on the right track this entire time,” she said.

Grewell was happy to report that all 12 of the business centers have completed the offline remediation process, which she said was not an easy or a cheap task as it involves shutting the towers down and undergoing extensive cleaning. Moving forward, any Legionella case reported to Grewell and the state will not be considered part of the outbreak and will instead be considered one of the 30 to 70 cases typically reported every year.

“I just want to say thank you to all of the local partners, the business centers, community partners, state, federal, Board of Supervisors, Board of Health, everybody that was involved in this outbreak response, and we will continue to press forward,” she said.

She has fielded questions about potential regulation of cooling towers going forward, and Grewell told the board it would likely need to be handled at a local level by either a city or county ordinance. As she opened up the floor to questions, Supervisor Jarret Heil asked if the identity of the business center that did test positive for Legionella would be made public.

She responded that the information would not be made public as the business’s privacy is protected under the Iowa Code section 139A for communicable disease because it is not an ongoing threat, and the problem was mitigated. Heil followed up with a question about whether it would have been different if a definitive match had been determined.

“That is something I am not fully sure of, but I still believe that they might not have shared it because, again, they took care of the process,” Grewell said. “If the business center would have just not done anything and not cooperated, then maybe there would’ve been some different actions taken. But again, all business centers cooperated, which was very good on our part. Some of them may have taken a little longer. Some of them may have taken a little longer for us to get in there and provide their information, but all of them did do the processes that we were asking them to, which again, a lot of them were big financial undertakings for these places. (It’s) not cheap to clean cooling towers.”

Fellow Supervisor Kevin Goodman called the situation “a difficult subject” and wondered why the outbreak happened specifically in Marshalltown. Grewell replied that it was hard to know as cooling towers are located all over the state and the country, and she said it could’ve been negligence by the business owner through improper water management processes.

“I think this experience has opened up the eyes of everybody — not only business owners but people — to make sure that they have water management processes, and they are handling them appropriately,” Grewell said.

Other local public health agencies across Iowa are asking the same questions, she added, and Legionella can develop from other sources such as CPAP and BiPAP machines, showers and faucets. Heil thanked Grewell for her hard work throughout the process and expressed his sympathies for the families of the two individuals who died as a result of the outbreak.

“I think this was a learning curve for many of us. I had never even heard what this was. I had no idea what Legionella was. I had no reason to know what it was before this, so I learned a lot about it,” he said. “At times, the public’s wanting to know information right away in real time, and we do the best we can on that. And I thought you did that as well. At the same time, there are laws we’ve got to follow on making sure that personnel information and particular information is protected. You did that well, and for us to have a close to this now is a good chapter to have closed. We look forward to not having to work on these things again, but you’re certainly prepared to do so if we do.”

The Legionella section of the Iowa Department of Health and Human Services (HHS) website will no longer be updated due to the close of the outbreak, and it has moved back to its regular order on the list of reportable diseases. The state will also be putting out a fact sheet on cooling tower mitigation at some point in the future, and Marshall County Public Health (MCPH) will have those links available as well.

In other business, the board:

Approved a memorandum of understanding between Marshall County and PPME Local 2003 I.U.P.A.T (Secondary Roads) and authorized the vice chair to sign (Chair Carol Hibbs was absent).

Approved an alcohol license for Durnan Wine LLC doing business as Madison County Winery for an upcoming Friends of Marshall County Conservation trivia event.

Approved the purchase of a 2027 Volvo VHD64F300 tandem axle chassis from GATR of Des Moines at a cost of $155,256.

Approved the 2025 county weed commissioner’s annual report.

Approved the purchase of a dump body, front plow, wing plow, underbody scraper, v-box salt and sand spreader, prewet system and installation of all items on the 2027 Volvo VHD64F300 from Henderson Products Inc. of Manchester at a cost of $208,636.16.

Approved the Iowa DOT cooperative agreement for the primary road project at the intersection of U.S. 30 and Binford Avenue.