What is Legionnaire’s

Disease?

Legionella is a waterborne bacterium that causes Legionnaires’ disease. The Legionella bacteria is spread through breathing in droplets of water or mist from water sources carrying the bacteria. It is spread through water systems and devices. Cooling towers are also a source of Legionella bacteria. In NYS, all owners of cooling towers are required to register, maintain, sample, disinfect and notify local health departments and the public of elevated levels of Legionella. Legionella bacteria thrive in stagnant, warm water between 77-113 degrees Fahrenheit. Legionella is not transmitted from person to person. The bacteria can cause a severe form of pneumonia called Legionnaire’s disease.

According to the NYS Department of Health, sporadic cases of Legionnaire’s Disease is common with around 25,000 cases diagnosed annually in the US. An additional unknown number are infected with the Legionella bacterium and experience mild to no symptoms.

Symptoms

Symptoms of early Legionnaire’s disease are similar to the flu and include muscle aches, headache, tiredness and dry cough followed by high fever, chills and occasionally diarrhea.

According to data provided by Wayne County Public Health, there have been 32 cases of Legionnaire’s disease reported since January 2023-July 2026. 

A local case

One such local case occurred several weeks ago, and began with symptoms of a cold. Lethargy, fever, aches and a major headache.  The “very painful headache”, was the reason Mark Plyter of Williamson finally had his wife take him to Urgent Care. That visit ended with health professionals sending him to the closest Emergency Room (Newark Wayne Hospital). Mark was diagnosed with pneumonia (specifically Legionella bacterium pneumonia). He also was immediately treated for sepsis. “I was very sick and spent 8 days in the hospital. I never should have waited. It began on a Thursday and I talked myself into waiting until Monday to be seen. Any of my symptoms could have been fatal.”

Outbreaks and Timing

Outbreaks of Legionnaire’s disease occur most often in the summer but cases occur all year round. In Wayne County, cases are more frequently reported in the summer months. Individual cases are investigated by the local health department to confirm the diagnosis and rule out an outbreak. If an outbreak occurs, an investigation will take place to look for a possible environmental source.

Anyone with a weakened immune system, a history of chronic lung conditions, former smokers, and adults 50 and older are at greater risk for developing Legionnaire’s disease. Legionella bacteria can be present in our homes within our water systems including unused taps, showers and faucets, within humidifiers and CPAP machines that vaporize water, hot tubs, and other sources of warm water with inadequate chlorine levels. Outdoor hazards include stagnant water sitting inside garden hoses exposed to direct sun and reservoirs filled with tap water.

Prevention

The key to preventing Legionella bacteria is to reduce the risk of Legionella growth and spread. Wayne County Public Health says to protect your household from Legionella bacteria, flush the pipes in your home regularly, run idled faucets and showers before use and use distilled water only in CPAP machines and humidifiers. Treat and test hot tubs with chlorine or bromine and drain garden hoses of water after each use and store out of direct sunlight.

For more information on Legionella visit https://www.cdc.gov/legionella/ or https://www.health.ny.gov/environmental/water/drinking/legionella. If you have questions or would like more information e-mail Wayne County Public Health at wcph@waynecountyny.gov.