ICD-11 classes
01 Certain infectious or parasitic diseases
Other bacterial diseases
1C19 — Legionellosis
1C19.1 — Legionnaires disease

ICD-11 1C19.1 — Legionnaires disease

Legionnaires’ disease, the pneumonic form, has an incubation period of 2 to 10 days (but up to 16 days has been recorded in some outbreaks). Initially, symptoms are fever, loss of appetite, headache, malaise and lethargy. Some patients may also have muscle pain, diarrhoea and confusion. There is also usually an initial mild cough, but as many as 50% of patients can present phlegm. Blood-streaked phlegm or hemoptysis occurs in about one-third of the patients. The severity of disease ranges from a mild cough to a rapidly fatal pneumonia. Death occurs through progressive pneumonia with respiratory failure and/or shock and multi-organ failure.

The diagnosis includes nothing.

The diagnosis excludes nothing.

It has no clarifying diagnoses.