What is the typical mortality range for Legionella pneumonia in the community, and how can it change in healthcare-associated cases?

• A. 0% mortality with treatment
• B. 1% to 2% always
• C. 30% to 60% in all cases
• D. 5% to 15% in the community; up to 25-50% in healthcare-associated cases

Answer: (D)

Mortality from Legionella pneumonia varies with setting and patient risk. In the community, deaths occur but the rate is generally modest—roughly 5% to 15% when treatment is given promptly with appropriate antibiotics. In healthcare-associated cases, patients tend to be older and sicker, diagnosis can be delayed, and the illness is more severe, which can push mortality higher—up to about 25% to 50%. So, the statement that best fits what’s observed across these contexts is 5% to 15% in the community and up to 25% to 50% in healthcare-associated cases. The other options aren’t realistic: zero mortality with treatment isn’t accurate for Legionella; a fixed 1% to 2% ignores higher-risk patients; and 30% to 60% in all cases overstates mortality for typical community cases.