Legionnaires' disease is climbing fast in North Carolina, and state health officials are sounding the alarm. Reported cases jumped from 201 in 2024 to 310 in 2025, and public health leaders say the bacteria that cause the illness thrive in the warm, wet conditions that come with spring and summer. Everyday plumbing and cooling systems can turn into trouble spots, so officials are urging both residents and facility managers to take basic water-safety steps now to cut the risk.
In a Friday release, the North Carolina Department of Health and Human Services said the 310 cases recorded in 2025 marked a sharp increase from 201 cases in 2024 and noted that the trend tracks with what is being seen across the country. The agency pointed to common sources such as hot tubs, decorative fountains, cooling towers and large plumbing systems, and urged clinicians to keep Legionella on the radar when treating pneumonia that is severe or not getting better, according to NCDHHS.
How Legionnaires Spreads And Who’s Most Vulnerable
Legionnaires disease develops when people breathe in tiny droplets of water or mist that contain Legionella bacteria. It does not spread from person to person. Guidance from the CDC notes that adults 50 and older, current or former smokers, and people with chronic health conditions or weakened immune systems face the highest risk of serious illness. Health officials say awareness needs to climb along with the temperature, since warmer weather creates conditions that help the bacteria grow.
Simple Fixes For Homes And Buildings
State clinicians and local reporters say many of the best protections are surprisingly simple: flush faucets and showerheads that have been idle for several days, follow manufacturer instructions for cleaning hot tubs and medical devices, replace point-of-use filters on schedule, and drain garden hoses when they are not in use. "To prevent it, you need to keep things flushed," Dr. Erica Wilson told WUNC.
Employers and facility managers are being reminded to stick to workplace and regulatory rules for water-management plans and cooling-tower upkeep to reduce community-wide risk. The federal safety agency OSHA outlines control and prevention steps for large building systems, including regular monitoring and maintenance.
What The Data Show
North Carolina's 2024 legionellosis report documented 201 cases that year, found that cases occur across the state and typically peak in late spring and summer, and noted that most patients were hospitalized, with roughly 10% of reported cases resulting in death. The report warned that legionellosis is probably underdiagnosed because its symptoms can look a lot like other forms of pneumonia, and it pressed for broader testing and quick investigations when a possible source is identified. The full document includes county-level data and investigation guidance for health care settings, according to the 2024 legionellosis report from NCDHHS.
Officials emphasize that small, regular actions are enough to lower risk for most people, but say anyone who develops fever, cough, shortness of breath or confusion after a possible exposure should seek medical care and ask about Legionella testing. Residents with questions are encouraged to contact their local health department for community-specific guidance and resources.
