Back داء الفيالقة Arabic Легіянэлёз BE-X-OLD Легионелоза Bulgarian Legionarska bolest BS Legionel·losi Catalan Legionelóza Czech Legionærsyge Danish Legionellose German Νόσος των Λεγεωνάριων Greek Legiana malsano Esperanto

Legionnaires' disease

Legionnaires' disease
Other namesLegionellosis,[1] legion fever
Chest X-ray of a severe case of legionellosis upon admission to the emergency department
SpecialtyInfectious disease, pulmonology
SymptomsCough, shortness of breath, fever, muscle pains, headaches[2]
Usual onset2–10 days after exposure[2]
CausesBacteria of the Legionella type (spread by contaminated mist)[3][4]
Risk factorsOlder age, history of smoking, chronic lung disease, poor immune function[5]
Diagnostic methodUrinary antigen test, sputum culture[6]
PreventionGood maintenance of water systems[7]
TreatmentAntibiotics[8]
Prognosis10% risk of death[8]
Frequency~13,000 severe cases a year (US)[9]

Legionnaires' disease is a form of atypical pneumonia caused by any species of Legionella bacteria,[3] quite often Legionella pneumophila. Signs and symptoms include cough, shortness of breath, high fever, muscle pains, and headaches.[2] Nausea, vomiting, and diarrhea may also occur.[1] This often begins 2–10 days after exposure.[2]

A legionellosis is any disease caused by Legionella, including Legionnaires' disease (a pneumonia) and Pontiac fever (a related upper respiratory tract infection),[10] but Legionnaires' disease is the most common, so mentions of legionellosis often refer to Legionnaires' disease.

The bacterium is found naturally in fresh water.[4] It can contaminate hot water tanks, hot tubs, and cooling towers of large air conditioners.[4] It is usually spread by breathing in mist that contains the bacteria.[4] It can also occur when contaminated water is aspirated.[4] It typically does not spread directly between people, and most people who are exposed do not become infected.[4] Risk factors for infection include older age, a history of smoking, chronic lung disease, and poor immune function.[5][11] Those with severe pneumonia and those with pneumonia and a recent travel history should be tested for the disease.[12] Diagnosis is by a urinary antigen test and sputum culture.[6]

No vaccine is available.[7] Prevention depends on good maintenance of water systems.[7] Treatment of Legionnaires' disease is commonly conducted with antibiotics.[8] Recommended agents include fluoroquinolones, azithromycin, or doxycycline.[13] Hospitalization is often required.[12] The fatality rate is around 10% for healthy persons and 25% for those with underlying conditions.[8]

The number of cases that occur globally is not known.[1] Legionnaires' disease is the cause of an estimated 2–9% of pneumonia cases that are acquired outside of a hospital.[1] An estimated 8,000 to 18,000 cases a year in the United States require hospitalization.[9] Outbreaks of disease account for a minority of cases.[1][14] While it can occur any time of the year, it is more common in the summer and autumn.[9] The disease is named after the outbreak where it was first identified, at a 1976 American Legion convention in Philadelphia.[15]

  1. ^ a b c d e Cunha BA, Burillo A, Bouza E (23 January 2016). "Legionnaires' disease". Lancet. 387 (10016): 376–385. doi:10.1016/s0140-6736(15)60078-2. PMID 26231463. S2CID 28047369.
  2. ^ a b c d "Legionella (Legionnaires' Disease and Pontiac Fever) Signs and Symptoms". Centers for Disease Control and Prevention (CDC). 26 January 2016. Archived from the original on 12 March 2016. Retrieved 21 March 2016.
  3. ^ a b "Legionella (Legionnaires' Disease and Pontiac Fever) About the Disease". Centers for Disease Control and Prevention (CDC). 26 January 2016. Archived from the original on 25 March 2016. Retrieved 21 March 2016.
  4. ^ a b c d e f "Legionella (Legionnaires' Disease and Pontiac Fever) Causes and Transmission". Centers for Disease Control and Prevention (CDC). 9 March 2016. Archived from the original on 25 March 2016. Retrieved 21 March 2016.
  5. ^ a b "Legionella (Legionnaires' Disease and Pontiac Fever) People at Risk". Centers for Disease Control and Prevention (CDC). 26 January 2016. Archived from the original on 27 March 2016. Retrieved 21 March 2016.
  6. ^ a b "Legionella (Legionnaires' Disease and Pontiac Fever) Diagnostic Testing". Centers for Disease Control and Prevention (CDC). 3 November 2015. Archived from the original on 12 March 2016. Retrieved 21 March 2016.
  7. ^ a b c "Legionella (Legionnaires' Disease and Pontiac Fever) Prevention". Centers for Disease Control and Prevention (CDC). 26 January 2016. Archived from the original on 25 March 2016. Retrieved 21 March 2016.
  8. ^ a b c d "Legionella (Legionnaires' Disease and Pontiac Fever) Treatment and Complications". Centers for Disease Control and Prevention (CDC). 26 January 2016. Archived from the original on 29 March 2016. Retrieved 21 March 2016.
  9. ^ a b c "Legionella (Legionnaires' Disease and Pontiac Fever) History and Disease Patterns". Centers for Disease Control and Prevention (CDC). 22 January 2016. Archived from the original on 25 March 2016. Retrieved 21 March 2016.
  10. ^ Harrison's Principles of Internal Medicine (21st ed.). New York: McGraw Hill. 2022. p. 1249. ISBN 978-1-264-26850-4.
  11. ^ "Legionella: Causes, How it Spreads, and People at Increased Risk". Centers for Disease Control and Prevention (CDC). 30 April 2018. Retrieved 17 September 2019.
  12. ^ a b "Legionella (Legionnaires' Disease and Pontiac Fever) Clinical Features". Centers for Disease Control and Prevention (CDC). 28 October 2015. Archived from the original on 12 March 2016. Retrieved 21 March 2016.
  13. ^ Mandell LA, Wunderink RG, Anzueto A, et al. (1 March 2007). "Infectious Diseases Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults". Clinical Infectious Diseases. 44 (Suppl 2): S27–72. doi:10.1086/511159. PMC 7107997. PMID 17278083.
  14. ^ "Legionella (Legionnaires' Disease and Pontiac Fever) Prevention". Centers for Disease Control and Prevention (CDC). 28 October 2015. Archived from the original on 12 March 2016. Retrieved 21 March 2016.
  15. ^ "Legionella (Legionnaires' Disease and Pontiac Fever)". Centers for Disease Control and Prevention (CDC). 15 January 2016. Archived from the original on 22 March 2016. Retrieved 21 March 2016.

Developed by StudentB