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Published on 20 December 2024

Legionellosis (Legionnaires' disease)

Legionellosis is first and foremost a disease of the respiratory tract. It is caused by bacteria of the Legionella genus which are found naturally in water. Infection occurs primarily through inhaling aerosols – fine water droplets – that contain Legionella bacteria.

Federal Office of Public Health FOPH

Communicable Diseases Division
Schwarzenburgstrasse 157
Switzerland - 3003 Bern