Legionnaires' disease: Its causes, symptoms and treatment

Legionnaires’ disease is a severe form of pneumonia caused by Legionella bacteria. This bacteria can also lead to a milder illness called Pontiac fever, which resembles flu-like symptoms.

Here’s what you should know:

How does it spread?

Legionella bacteria spread when someone inhales tiny droplets of contaminated water, commonly found in hot tubs, industrial air conditioning systems, and even drinking water.

Outbreaks often occur in large and complex water systems found in places like hotels, hospitals, and cruise ships.

The bacteria can also survive and spread in soil, occasionally causing infections when people garden using contaminated soil. 

However, in most cases, people do not transmit Legionnaires’ disease or Pontiac fever to others.

What are the symptoms?

Symptoms of Legionnaires disease typically appear between two to 10 days after exposure to the bacteria and can include: 

• Headache
• Muscle aches
• Shortness of breath
• Cough
• Fever 

Who is at higher risk?

Those most susceptible to Legionnaires’ disease include adults over 50, individuals with weakened immune systems, and smokers.

Can it be treated?

Antibiotics are used to treat Legionnaires’ disease, though it often requires hospitalization. 

Anyone suspecting exposure to Legionella or experiencing symptoms of Legionella disease or pneumonia should promptly contact a doctor. It’s important to mention any exposure to Legionella, hot tub use, recent travels, or hospital stays in the past two weeks.

For more information on Legionnaires’ disease, visit the CDC website.