Health officials in Michigan are sounding the alarm over the spread of Legionnaires’ disease after two people died of the infection this summer. 

The Michigan Department of Health and Human Services reportedly said that both patients had tested positive for Legionnaires’ disease

Legionnaires’ disease is a severe form of pneumonia that causes lung inflammation, and complications from the disease can be fatal.

It is caused by a bacterium, known as Legionella that is primarily spread through the inhalation of contaminated water droplets or aerosols.

These contaminated droplets can be released from various water sources, including cooling towers, hot tubs, showers and decorative fountains.

No details about the deceased individuals in Michigan, including their names, ages or genders, have been shared by the retirement home or officials. 

Health officials in New York are also contending with a possible Legionnaires’ outbreak. The New York City Health Department issued a warning after eight cases of Legionnaires’ disease were confirmed in Central Harlem this week. 

Health officials in Detroit are sounding the alarm over the spread of Legionnaires’ disease after two people died of the infection this summer

According to ABC7, both of the affected Allegria Village residents were living in two separate units and had moved into the facility recently. 

Avani Sheth, chief medical officer of HHVS, said of the 2025 cases: ‘Wayne County Health, Human, and Veterans Services was recently notified of cases of Legionella pneumonia (Legionnaires’ disease) among residents of Allegria Village in Dearborn, Michigan.’

An investigation into the spread of the disease is currently being conducted in Wayne County by HHVS officials. 

Sheth noted that the investigation is in its early stages with the goal to ensure a safe and healthy living environment for residents and staff.

The disease is not spread by drinking or swimming in water, except in the instance of water accidentally getting into the lungs instead of the stomach. 

Early symptoms of the disease include fever, loss of appetite, headache, lethargy, muscle pain and diarrhea. 

The severity can range from a mild cough to fatal pneumonia, and treating infection early with antibiotics is key for survival. 

Most healthy individuals do not become infected after exposure to Legionella, however, people most at risk include adults over 50, smokers and those with weakened immune systems or chronic lung conditions. 

Officials confirmed that both people were living in Allegria Village, a continuing care retirement community in Dearborn, Michigan (pictured)

The disease is treated with antibiotics including azithromycin, fluoroquinolones (like levofloxacin or moxifloxacin), and sometimes doxycycline or rifampin. 

The CDC reports that cases of Legionnaires’ disease have been increasing since the early 2000s and hit a peak in 2018 with 9,933 confirmed cases. 

Due to reporting discrepancies and various databases, data on the number of legionnaires’ cases and deaths is fragmented and varies. 

However, according to the CDC’s National Notifiable Diseases Surveillance System (NNDS), from 2000 through 2019, a total of 82,352 confirmed Legionnaires’ disease cases were reported from 52 US jurisdictions.

About one in 10 people who become sick will die. 

The odds of death are higher when the disease is contracted in a hospital setting, with at least one in four dying. 

The most reliable way to determine if your water is contaminated with Legionella is to have it tested by a qualified laboratory. 

Home testing kits are also available, which involve collecting water samples and sending them to a lab for analysis. 

Earlier this year, one person died and several were hospitalized due to an outbreak of Legionnaires’ disease at a senior living facility in Vermont. It originated from the care home’s water system.

In general, the CDC reports that cases of Legionnaires’ disease have been increasing since the early 2000s, with a peak in 2018 

Legionella can colonize and grow within complex communities of microorganisms called biofilms that form on surfaces within water systems. 

Once there, the bacteria seeps into the water and becomes aerosolized.

Plumbing systems, especially those associated with warm water, such as hot water tanks and distribution pipes, can also serve as reservoirs for Legionella bacteria to multiply.

From there it can contaminate water in pipes. Stagnant or low-flow areas in pipes also foster Legionella growth.