Diagnosis

Legionnaires' disease is like other types of pneumonia. To find the legionella bacteria quickly, a healthcare professional might use a test that checks the urine for things that trigger the immune system, called antigens. Other tests might include:

  • Blood tests.
  • Chest X-ray. This doesn't show the type of infection. But it can show how much infection is in the lungs.
  • Tests on a sample of mucus from the lungs, called sputum, or lung tissue.

Treatment

Antibiotics treat Legionnaires' disease. The sooner therapy is started, the lower the chance of getting serious complications. Often, a hospital stay is needed. Pontiac fever goes away on its own without treatment and causes no other problems.


Preparing for your appointment

You're likely to start by seeing your family healthcare professional. You may also see a doctor who specializes in treating lung disease, called a pulmonologist, or a specialist in infectious diseases. Or you might need to get emergency care.

What you can do

Make a list of:

  • Key facts about your illness, including your symptoms and when they began. Record your temperature.
  • Facts about yourself that might be related. These include having been in a hospital recently or having traveled recently and where you stayed.
  • All medicines, vitamins and other supplements you take, including doses.
  • Questions to ask your provider.

Bring a family member or friend along, if you can, to help you gather all the facts you get.

Questions you might ask your provider include:

  • What is likely causing my symptoms?
  • What are other possible causes?
  • What tests do I need?
  • What is the best course of action?
  • I have other health conditions. How will this illness affect them?
  • Do I have to go to a hospital? If so, for how long?

Be sure to ask all the questions you have about your condition.

What to expect from your doctor

A member of your healthcare team is likely to ask you questions, including:

  • Have your symptoms been ongoing?
  • Have your symptoms gotten worse?
  • What, if anything, seems to improve your symptoms?
  • What, if anything, seems to make your symptoms worse?

What you can do in the meantime

To keep from making your condition worse, follow these tips:

  • Don't smoke or be around smoke.
  • Don't drink alcohol.
  • Stay out of work or school, and rest as much as you can.
  • Drink plenty of fluids.

If you get sicker before you see a healthcare professional, get emergency care.


Apr 19, 2025

  1. Murdoch D, et al. Microbiology, epidemiology, and pathogenesis of Legionella infection. https://www.uptodate.com/contents/search. Accessed April 6, 2023.
  2. Legionella (Legionnaires' disease and Pontiac fever). Centers for Disease Control and Prevention. https://www.cdc.gov/legionella/about/index.html. Accessed April 6, 2023.
  3. Loscalzo J, et al., eds. Legionella infections. In: Harrison's Principles of Internal Medicine. 21st ed. McGraw Hill; 2022. https://accessmedicine.mhmedical.com. Accessed April 6, 2023.
  4. Murdoch D, et al. Treatment and prevention of legionella infection. https://www.uptodate.com/contents/search. Accessed April 6, 2023.
  5. Legionellosis. World Health Organization. https://www.who.int/news-room/fact-sheets/detail/legionellosis. Accessed April 6, 2023.

CON-XXXXXXXX

Have 2X the impact!

Make a gift that can go twice as far to advance healthcare research.