Thumbnail image of: Respiratory System: Illustration

Legionnaires’ Disease

What is Legionnaires’ disease?

Legionnaires’ disease is a rare lung infection caused by Legionella bacteria.

What is the cause?

Legionnaire’s disease is spread by breathing in water droplets that contain the bacteria. The bacteria live in warm water that may be found in large plumbing or air-conditioning systems, or in hot tubs. The bacteria do not spread person to person, or from car or household air-conditioning units.

Most people who are exposed to the bacteria do not get sick. You have a higher risk of getting sick with Legionnaire’s disease if:

  • You are over 65 years old.
  • You smoke.
  • You have allergies, asthma, or other lung diseases.
  • Your immune system doesn’t work normally, for example, because of cancer or cancer therapy, diabetes, kidney failure, AIDS, or use of steroid drugs in high doses.
  • You abuse alcohol

What are the symptoms?

The first symptoms of this disease are:

  • Fever and chills
  • Shortness of breath
  • Headache
  • General ill feeling

Symptoms that start 1 to 2 days later may include:

  • Cough, which can be dry, or it may bring up mucus or blood
  • Chest pain
  • Confusion
  • Diarrhea
  • Stomach pain

How is it diagnosed?

Your healthcare provider will ask about your symptoms and medical history and examine you. Tests may include:

  • Chest X-ray
  • Blood and urine tests
  • Sputum culture, which is a test of a sample of mucus coughed up from deep in your lungs

How is it treated?

Your healthcare provider may prescribe antibiotics you can take by mouth at home. If you are very ill, you may need to be in the hospital. Treatment may include:

  • Giving you oxygen. You may need to have a tube in your throat and a machine to help you breathe.
  • Giving you IV fluids and medicines, such as antibiotics to treat infection and inhaled medicines to open up the airway.

How can I take care of myself?

Follow the full course of treatment prescribed by your healthcare provider. In addition:

  • If you are taking an antibiotic, take the medicine for as long as your healthcare provider prescribes, even if you feel better. If you stop taking the medicine too soon, you may not kill all of the bacteria and you may get sick again.
  • Drink more liquids (water or tea) every day to help you cough up mucus more easily unless your provider has told you to limit your fluids.
  • Cough up mucus as much as possible. Use cough medicine only if your provider recommends it.
  • Don’t smoke, and stay away from others who are smoking.
  • Avoid breathing dust and chemical fumes.
  • Get extra rest.
  • Use a humidifier to put more moisture in the air. Avoid steam vaporizers because they can cause burns. Be sure to keep the humidifier clean, as recommended in the manufacturer’s instructions. It’s important to keep bacteria and mold from growing in the water container.
  • Take nonprescription medicine, such as acetaminophen, ibuprofen, or naproxen to treat pain and fever. Read the label and take as directed. Unless recommended by your healthcare provider, you should not take these medicines for more than 10 days.
    • Nonsteroidal anti-inflammatory medicines (NSAIDs), such as ibuprofen, naproxen, and aspirin, may cause stomach bleeding and other problems. These risks increase with age.
    • Acetaminophen may cause liver damage or other problems. Unless recommended by your provider, don’t take more than 3000 milligrams (mg) in 24 hours. To make sure you don’t take too much, check other medicines you take to see if they also contain acetaminophen. Ask your provider if you need to avoid drinking alcohol while taking this medicine.
  • Use a heating pad on a low setting to reduce chest pain. Be careful not to fall asleep while you are using the heating pad.
  • Contact your healthcare provider if you have new or worsening symptoms.

Ask your provider:

  • How and when you will hear your test results
  • How long it will take to recover from this illness
  • If there are activities you should avoid and when you can return to your normal activities
  • How to take care of yourself at home
  • What symptoms or problems you should watch for and what to do if you have them

Make sure you know when you should come back for a checkup. Keep all appointments for provider visits or tests.

Developed by RelayHealth.
Adult Advisor 2015.1 published by RelayHealth.
Last modified: 2014-10-21
Last reviewed: 2014-07-31
This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.
Copyright ©1986-2015 McKesson Corporation and/or one of its subsidiaries. All rights reserved.

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