Legionnaires' disease outbreak in Austria
Since the beginning of 2025, 41 people in Vorarlberg have contracted Legionella. Since the end of last week, eight new cases have been added. 37 of these cases occurred in the Lower Rhine Valley - Bregenz region and surrounding areas.
The state's environmental institute is still intensively working on the search for sources. Legionella contamination was detected in several private households and cooling towers.
For the first time, matches were found between the sequencing results of the sick people and environmental samples. In the coming weeks, however, it will be necessary to observe whether further illnesses occur and whether there are possibly further sources.
As of February 26, the first evaluations of the Legionella strains (sequencing) from several patients are available. These patient strains show a strong genetic relationship, so it can be assumed that they were infected from the same source of infection.
Legionella was also detected in various concentrations in several environmental samples. However, some environmental samples showed completely different types of Legionella, which is why these must be ruled out as a source of infection.
However, the same type of legionella was detected in the cooling tower of a plant, which is why this cooling tower is a possible source of infection. When the legionella contamination was discovered last week, this cooling tower was taken out of service and immediately disinfected and cleaned.
However, since it cannot be ruled out that other sources caused these infectious diseases, the search for sources continues unabated.
All relevant authorities in the country continue to monitor the situation closely.