Viruses were long confused with bacteria. But since we discovered them, these intracellular parasites have shaken up our conception of life, as they still refuse to fit into boxes…
Some viruses can be dangerous to humans, and that’s how we know them best. Our proximity to the wild world has allowed the emergence of new infectious diseases… which have sometimes turned into pandemics. However, the majority of viruses are certainly harmless to us and they are also essential members of biodiversity and the evolution of species. So, how did we discover the nature and functioning of viruses? How do they question our relationship with the living world?
To talk about it
Frédéric Keck is an anthropologist, research director at the CNRS
Tania Louis is a doctor in virology, scientific mediator, and author of “La folle histoire des viruses”, published in 2020 by Humasciences
Viruses, a living entity?
Until the 19th century, it was thought that life could be created from the inert, this is the theory of spontaneous generation. But Pasteur will put an end to this theory, and in this wake, the reflection around the living or non-living nature of viruses will open up…
L’indentification des virus
In the history of the discovery of viruses, three names are important: Adolf Mayer, Dimitri Ivanovski, Martinus Beijerinck. It was not a human disease that allowed them to be discovered, but a plant disease! Because the first virus discovered was that of the tobacco mosaic virus… But how do we manage to see it?
From research on tobacco mosaic, the virus will be defined as a non-filterable infectious entity, unlike bacteria. A method that will be used in the 1930s to see the virus, before the electron microscope, is crystallography. These are biochemists who actually identify that in this sap of the infected tobacco leaf; there are like salt crystals. They will manage to model these salt crystals, and this will be the new model for thinking of viruses as crystals.. Frederick Keck
Sound references
The World of Microbes, 3: Pasteurextract from the program “Heure de culture française”, RDF/RTF, 1948
The virulence of viruses, excerpt from the program “Emission médicale” (alternative title: Live from the Pasteur Institute), RTF/ORTF, 1973
Stup Virus by Stupeflip
G in B – I thought I was strongby Axel Bauer, Francis Cabrel, Zazie
Reading an excerpt from NanaEmile Zola, 1880
