Two elderly residents have died in the Savoie department of south-eastern France following a localized outbreak of Legionnaires' disease that infected 41 people.
The Auvergne-Rhone-Alpes regional health agency, known as the ARS, reported in a statement on Tuesday that 41 cases of the bacterial lung infection were declared between June 1 and August 10, 2026. Health authorities confirmed that 40 of those diagnosed required hospital treatment. Both of the fatal cases involved patients over 80 years old.
Local health officials stated that the patients diagnosed during the summer outbreak range in age from 26 to 91 years old. Epidemiological data provided by the agency shows that 34 of the infected individuals reside permanently in Savoie, while seven others had visited the department during the exposure window.
Water Sampling and Focus on Chambery
Epidemiological investigations are currently underway to pinpoint the origin of the bacterial contamination. Health authorities are prioritizing searches in the western sector of the department and the basin surrounding Chambery, the prefecture of Savoie. The health agency said that 25 of the 41 confirmed patients live in or had frequented that area.
To identify the source, sampling teams have collected approximately 30 environmental samples across the region. The health agency explained that technicians took samples from water networks in collective residential buildings, industrial cooling towers, supermarkets, and restaurants. Officials said they expect to receive the initial testing results by August 17.
Bacterial Transmission and Regional Context
Legionnaires' disease, also known as legionellosis, is a severe form of pneumonia caused by Legionella bacteria. The illness is contracted when individuals inhale microscopic droplets of water contaminated with the bacteria, often generated by air conditioning systems, showers, or industrial cooling units. It does not spread directly from person to person. Health authorities note that the infection proves fatal in approximately 10 percent of cases, with elderly individuals and those with weakened immune systems facing the highest risk.
The Auvergne-Rhone-Alpes regional health agency registers between 200 and 400 cases of Legionnaires' disease each year across its territory in south-eastern France. The current outbreak comes less than a year after a similar cluster in September 2025, when two people died from the disease in the region around Albertville, another major town in Savoie.
