Disease at a Glance

Summary
Legionnaires' disease is a severe type of pneumonia caused by the bacteria Legionella. The species Legionella pneumophila causes most cases, but other species of Legionella can also cause the disease. It is named Legionnaires' disease because it was first discovered after a pneumonia outbreak among people who attended an American Legion Convention in Philadelphia, Pennsylvania in 1976. Most people exposed to Legionella do not become sick with Legionnaires' disease. People who do become sick usually develop symptoms within 2 to 10 days after exposure, but it may take longer. The first symptoms may include headache, chills, muscle pains, and a fever that can be 104°F (40°C) or higher. Additional symptoms usually develop 1 to 2 days after the first symptoms and may include coughing, shortness of breath, chest pain, diarrhea, nausea and vomiting, and confusion. While Legionnaires' disease mainly affects the lungs, it sometimes causes infections in other parts of the body, such as the heart or within body wounds. A person can become infected from Legionella when they inhale mist or water droplets that contain the bacteria. Sources of exposure may include showers, faucets, whirlpools, grocery store misters, and water droplets passing through ventilation systems in large buildings (such as hotels, office buildings, and hospitals). People who are more susceptible to developing Legionnaires' disease after an exposure include adults over age 50, current or former smokers, and people who have a weakened immune system or a chronic disease. Generally, neither the bacteria nor Legionnaires' disease is spread directly from person to person. While large exposures can result in outbreaks, the disease usually occurs in single, isolated cases. Legionnaires' disease may be suspected by symptoms. Pneumonia can be confirmed by a chest X-ray. Legionnaires' disease is diagnosed when one of the species of Legionella is found to be the cause of the pneumonia by testing a urine sample (urine culture) or a sample of saliva and mucus that is coughed up (sputum culture).

About Legionnaires’ disease

Many rare diseases have limited information. Currently GARD is able to provide the following information for Legionnaires’ disease:

  • Population Estimate:In the US, there are less than 50,000 with this disease.
  • Symptoms:May start to appear at any time in life.
  • Experts:GARD is not currently aware of a specialist directory for this condition.
  • Organizations:GARD is not aware of organizations specific to this condition. 

When do symptoms of this disease begin?
The most common ages for symptoms of a disease to begin is called age of onset. Age of onset can vary for different diseases and may be used by a doctor to determine the diagnosis. For some diseases, symptoms may begin in a single age range or several age ranges. For other diseases, symptoms may begin any time during a person's life.
Prenatal Selected
Before Birth
Newborn Selected
Birth-4 weeks
Infant Selected
1-23 months
Child Selected
2-11 years
Adolescent Selected
12-18 years
Adult Selected
19-65 years
Older Adult Selected
65+ years
Symptoms may start to appear at any time in life.

Symptoms

These symptoms may be different from person to person. Some people may have more symptoms than others and symptoms can range from mild to severe. This list does not include every symptom.
This disease might cause these symptoms:
Respiratory System

38 Symptoms

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Respiratory System

The respiratory system is made up of the lungs and the nose, mouth, throat, voice box, windpipe, diaphragm, and muscles of the chest wall. This system controls breathing, providing the body with oxygen and getting rid of carbon dioxide. Common symptoms of problems in the respiratory system include chronic cough, shortness of breath, chronic chest pain, coughing up blood, and chronic mucus production. Diseases of the respiratory system may be diagnosed and treated by a pulmonologist.

Causes

This section is currently in development. 

Advocacy and Support Groups

How can a patient organization be helpful?

Patient advocacy and support organizations offer many valuable services and often drive the research and development of treatments for their disease(s). Because these organizations include the life experiences of many different people who have a specific disease, they may best understand the resources needed by those in their community. Although missions of organizations may differ, services may include, but are not limited to:
 

  • Ways to connect to others and share personal stories
  • Easy-to-read information
  • Latest treatment and research information
  • Lists of specialists or specialty centers
  • Financial aid and travel resources
Please note: GARD provides the names of patient organizations for informational purposes only and not as an endorsement of their services. Please contact the organization directly if you have questions about the information or resources they provide.

What do disease-specific organizations do?

Some organizations build a community of patients and families impacted by a specific disease or group of related diseases. These organizations usually have more disease-specific information and services, including helping new members find others who have the same disease.

What do organizations that focus on a medical condition do?

Some organizations build a community of patients and families impacted by a medical condition, like epilepsy, or related conditions, like heart problems, that may also be a symptom in other diseases. These organizations usually have information and services focused more on the medical condition(s), but may also have information about associated diseases.

What do umbrella organizations do?

Rare disease umbrella organizations focus on improving the lives of all those impacted by rare diseases through education and advocacy efforts. Umbrella organizations provide a range of services for patients, families, and disease-specific organizations.

Patient Organizations

4 Organizations

Organization Name

Organization Type

Service

Country

Language

EveryLife Foundation for Rare Diseases
https://everylifefoundation.org/
Umbrella

Legionnaires’ Disease

Service

Information

Country

United States

Language

English

Spanish

Umbrella

Legionnaires’ Disease

Service

Information

Country

United States

Language

English

Umbrella

Legionnaires’ Disease

Service

Information

Country

United States

Language

English

National Organization for Rare Disorders
https://rarediseases.org/
Umbrella

Legionnaires’ Disease

Service

Information

Research

Country

United States

Language

English

Spanish

4 Organizations

Research

Why is Research Important for Rare Diseases?

Research increases what we know about rare diseases so that people can get a diagnosis more quickly and can know what to expect. Research also helps doctors better understand how well a treatment works and can lead to new treatment discoveries. It may even help improve diagnosis and treatment of more common diseases.

How do you find the right clinical study?

  • Discuss the clinical study with a trusted medical provider before enrolling
  • Review the "Study Description," which discusses the purpose of the study, and "Eligibility Criteria," which lists who can and cannot participate in the study
  • Work with the research coordinator to review the written informed consent, including the risks and benefits of the study
  • Inquire about the specific treatments and procedures, location of the study, number of visits, and time obligation
  • Determine whether health insurance is required and whether there are costs to the participant for the medical care, travel, and lodging
  • Ask questions. Remember, it is okay to decide not to participate in research

For More Information

Current clinical studies can be found by using ClincalTrials.gov. Doctors, other trusted medical professionals, and patient organizations may also be aware of studies. Researchers from participating institutions use the database to search for patients or healthy volunteers who meet their study criteria.

How do you find the right clinical study?

  • Discuss the clinical study with a trusted medical provider before enrolling
  • Review the "Study Description," which discusses the purpose of the study, and "Eligibility Criteria," which lists who can and cannot participate in the study
  • Work with the research coordinator to review the written informed consent, including the risks and benefits of the study
  • Inquire about the specific treatments and procedures, location of the study, number of visits, and time obligation
  • Determine whether health insurance is required and whether there are costs to the participant for the medical care, travel, and lodging
  • Ask questions. Remember, it is okay to decide not to participate in research

For More Information

Current clinical studies can be found by using ClincalTrials.gov. Doctors, other trusted medical professionals, and patient organizations may also be aware of studies. Researchers from participating institutions use the database to search for patients or healthy volunteers who meet their study criteria.

Last Updated: Nov. 8, 2021