September 02, 2025

Legionnaires’ Disease: Symptoms, Testing & How to Protect Yourself

Legionnaires’ Disease: Are You at Risk?

Did you know that the first outbreak of Legionnaires’ Disease occurred in Philadelphia, PA? With this disease recently hitting the news, we wanted to go over some quick basics.

 

What is Legionnaires’ Disease?

Legionnaires’ disease is a serious type of pneumonia caused by Legionella bacteria. It is also known as Legionellosis.

 

How do you get Legionnaires’ Disease?

You can get the infection by breathing in or aspirating small droplets of contaminated water. The water droplets can come from hot tubs, showers, or large building air conditioning units.

 

What are the symptoms of Legionnaires’ Disease?

Most of the symptoms are similar to pneumonia but may also include gastrointestinal symptoms and mental changes.

Being over age 50, smoking, having a chronic illness (like diabetes) or lung condition, having a weakened immune system, and recent stays in hospitals or care facilities can make someone more at risk.

Symptoms typically include: 
  • Nausea and vomiting
  • Shortness of breath
  • High fever
  • Headache
  • Chest pain
  • Confusion
  • Diarrhea
  • Fatigue
  • Chills
  • Cough

 

Can Legionnaires’ Disease be prevented?

Almost all (9 in 10) outbreaks are caused by ineffective water management and can be prevented ¹. You can lower your risk of getting the disease if you:

  • Clean all your water-related devices regularly, like humidifiers, water heaters, air conditioners, and nasal rinses.
  • Flush any faucets or showerheads that were unused for a week or more. Flush them by running the hot and cold faucets for at least two minutes before use.
  • Avoid exposure to water sources such as decorative foundations or hot tubs if you don’t know how well they are maintained.
  • Use windshield cleaner in your wiper fluid tank in your car instead of water.
  • Ask about how well your building’s water systems are maintained.

 

Testing and treatment for Legionnaires’ Disease

If you have pneumonia, lab tests such as urine or sputum tests can check for Legionella. Your provider may also order a blood test to see if you have been exposed to the bacteria.

Treatment is usually done in a hospital with antibiotics. Getting treatment early can increase the chances of getting better.

 

Choose HNL Lab Medicine

Legionnaires’ disease is a serious infection and can cause life-threatening complications like respiratory failure, kidney failure, and sepsis. Complications are fatal in about 1 out of every 10 people who get sick with Legionnaires’ disease ².

Protect yourself and your loved ones by managing all water systems. Discuss any symptoms or concerns with your healthcare provider. Get tested early, before symptoms become severe, so that you can quickly obtain proper treatment.

Remember to get your lab work completed at one of HNL Lab Medicine’s convenient locations. Stay safe, and choose HNL Lab Medicine.

 

REFERENCES
¹ Centers for Disease Control and Prevention. (2024, March 05). About Legionella control. U.S. Department of Health and Human Services. https://www.cdc.gov/control-legionella/about/.
² National Library of Medicine. (2024, July 19). Legionnaires’ disease. National Institutes of Health. https://medlineplus.gov/legionnairesdisease.html.