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Legionellosis history and symptoms

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Legionellosis may manifest with either Legionnaires’ disease or Pontiac Fever. Legionnaires’ disease is more severe and typically manifests with fatigue, malaise, symptoms of pneumonia (fever, dyspnea, chest pain, and cough) and occasionally diarrhea and nausea. In contrast, Pontiac fever is a milder form of respiratory flu-like disease (fever and cough) but does not result in pneumonia. Patients with legionellosis often report a recent history of travel, hospitalization, exposure to contaminated water, or exposure to healthcare settings.

History

  • Legionnaires’ disease typically manifests with pneumonia, which usually requires hospitalization and can be fatal in 10%–15% of cases.
  • In contrast, clinical manifestations of Pontiac fever are milder than Legionnaires’ disease. Pontiac fever typically manifests with influenza-like illness (fever, headache, and myalgias) but no signs of pneumonia. Pontiac fever can affect healthy people, as well as those with underlying illnesses, and symptoms occur within 72 hours of exposure.
  • Approximately 15%-20% of patients report a recent history of travel.
  • Patients often report recent hospitalizations and exposure to healthcare settings.[1][2]

Symptoms

Legionnaires’ Disease

Symptoms of Legionnaires’ disease may include:[1][2]

Pontiac Fever

There are no lower respiratory manifestations with Pontiac fever. Symptoms of Pontiac fever may include:

References

  1. 1.0 1.1 Top 10 Things Every Clinician Needs to Know About Legionellosis. Centers for Disease Control and Prevention. Accessed on August 5, 2015. http://www.cdc.gov/legionella/clinicians.html
  2. 2.0 2.1 Phin N, Parry-Ford F, Harrison T, Stagg HR, Zhang N, Kumar K; et al. (2014). “Epidemiology and clinical management of Legionnaires’ disease”. Lancet Infect Dis. 14 (10): 1011–21. doi:10.1016/S1473-3099(14)70713-3. PMID 24970283.

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