Nonpneumonic Legionnaires' disease

**Definition:** The non-pneumonic form (Pontiac fever) is an acute, self-limiting flu-like illness usually lasting 2–5 days. The incubation period is from a few and up to 48 hours. The main symptoms are fever, chills, headache, malaise and muscle pain (myalgia).

**Long definition:** Pontiac fever (PF) is a mild form of legionellosis manifesting with flu-like symptoms such as nausea, myalgia, fever, cough and headache but without pneumonia.