Legionnaires’ disease remains a serious public health issue in the United States, with notable outbreaks continuing in 2024. The disease, caused by waterborne Legionella bacteria, primarily affects individuals through inhalation of contaminated water droplets. According to the National Institutes of Health (NIH), Legionella bacteria can be found living in organic material attached to inner pipe surfaces in aging water infrastructure environments like cooling towers, plumbing systems and water features.
While many people exposed to Legionella may not experience severe symptoms, the disease can lead to a dangerous form of pneumonia, especially in vulnerable groups such as older adults, smokers or those with weakened immune systems. The outbreaks in 2024 serve as a reminder of the importance of proactive water system management to reduce the risk of infection.
In 2024, several major outbreaks across the United States emphasized the ongoing threat this disease poses. Below are three of the most notable cases.
1. Assisted Living Facility in Upstate New York
One of the most significant outbreaks occurred in September 2024 at an assisted living facility in Albany County, New York. This outbreak resulted in the deaths of three people with 10 individuals testing positive for the disease and 20 hospitalizations. Assisted living and long-term care facilities are particularly vulnerable environments due to the age and underlying health conditions of the residents.
2. Community-Wide Outbreak in Grand Rapids, Minnesota
Since early 2023 and continuing into 2024, cases of Legionnaires’ disease have been confirmed in Grand Rapids, Minnesota. Health officials confirmed 23 cases of Legionnaires’ disease in Grand Rapids since last April, up from 15 cases in March 2024. Officials were perplexed by the community-wide outbreak that started over a year ago, city and state health officials along with the University of Minnesota have continued testing water at locations throughout the city. While they couldn’t pinpoint the underlying cause, Grand Rapids began disinfecting its water supply with chloramine—a combination of chlorine and ammonia—to reduce the level of bacteria in the water system.
An outbreak like this demonstrates the serious public health risks associated with aging infrastructure and poorly maintained water systems. Regular inspections and comprehensive water management plans are critical in preventing similar occurrences and ensuring the safety and reliability of water systems.
3. Cooling Tower in Lincoln, New Hampshire
In August 2024, the New Hampshire Department of Health and Human Services issued an advisory when five people developed Legionnaires’ disease after being exposed to Legionella-contaminated water from a cooling tower in downtown Lincoln, New Hampshire.
Public health officials identified the cooling tower behind RiverWalk Resort as the source and partnered with the organization to address the contamination. The cooling tower remained in operation through remediation and additional tests were conducted to determine the contamination status.
Understanding Legionella Bacteria and Prevention
Legionella bacteria naturally occur in water systems and infect people who breathe in contaminated droplets from hot tubs, faucets, cooling towers, showers and similar water sources. Many exposed to Legionella experience mild or no symptoms. However, for vulnerable populations, such as those with compromised immune systems or the elderly, the bacteria can lead to a form of pneumonia called Legionnaires’ disease, which can be fatal if untreated. Symptoms typically begin around 14 days after exposure and include cough, fever, and shortness of breath.
Preventing Legionnaires’ disease involves rigorous water management protocols. Key preventative steps include controlling water temperatures to prevent Legionella growth, regularly cleaning and maintaining water systems, and ensuring appropriate levels of disinfectants. Building owners and facility managers are encouraged to adopt CDC-recommended water management programs to limit the risk of outbreaks.
Nationwide Accredited Laboratory Testing
If you are concerned about Legionella bacteria, contact a reputable HVAC and water treatment specialist who can perform preventative maintenance, as well as engage an accredited laboratory like SanAir Technologies Laboratory to test your water for contaminants. Call 888-895-1177 for more information.
