Legionnaires' Disease Outbreak in Basel Leaves One Dead and Dozens Ill

Health authorities in Basel have reported an outbreak of Legionnaires' disease that has resulted in 26 cases and one death. Of those infected, 25 people were hospitalized, and seven required treatment in intensive care. The majority of the cases were concentrated in the Kleinbasel district, although some isolated cases appeared in other parts of the city. The patients had a median age of 66 years, and the group consisted of 20 men and six women.

Authorities identified cooling towers on the roof of an office building as the primary source of the contamination. Out of ten installations tested by the cantonal laboratory, eight exceeded the permitted threshold for Legionella. Two of these towers specifically contained Legionella pneumophila, the species responsible for most human infections. These two installations were taken out of service on Friday. The health department has since urged operators of other large industrial plants using wet cooling towers to contact the laboratory for further clarification.

Legionnaires' disease is a form of pneumonia caused by the inhalation of contaminated aerosols. It is not transmitted from person to person. While the center left source focused on the immediate public health warnings and the specific number of contaminated installations, the center right source provided more clinical detail regarding patient risk factors and the environmental conditions that allow the bacteria to thrive, such as specific water temperatures and recent heatwaves.