This article is taken from the monthly Sciences et Avenir n°936, dated February 2025.
Dogmas in medicine die hard. Thus, "We have long believed that a healthy lung was necessarily sterile ", acknowledges Professor Geneviève Héry-Arnaud, a bacteriologist specializing in pulmonary microbiota at Brest University Hospital. However, in 1899, work had come to contradict what was to become dogma. A study on 23 cadavers free of pulmonary disease had revealed the presence of bacteria in the respiratory tract. "The only error in this otherwise original study was to conclude that the bacteria were pathogenic" she says. While these were commensal bacteria, which live in harmony with the subject.
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