making microbiology easy

Viruses at the service of humanity?

Once upon a time, the English bacteriologist Ernest Hankin demonstrated for the first time the presence of anti-bacterial entities in the waters of Indian rivers, putting humanity on the path to a promising anti-infectious therapy that is more relevant than ever.

Let’s go back to 1896, on the banks of the Gange, where cholera is ravaging. Hankin, who had been sent to work on the cholera bacillus, was surprised by the small quantity of Vibrio cholerae in the river. He also wondered why, when cholera broke out on the banks, it did not go down to the villages downstream. Since the disease is carried by water, its spread should follow the river. Hankin then revealed the existence of a substance that, even after passing through a Chamberland filter, attacked the bacteria responsible for cholera with formidable efficiency.

This curiosity called out to Félix d’Hérelle, a French researcher who, identified biological entities capable of forming lysis patches on bacterial cultures, in 1917. He simply named these bacteria eaters: “bacteriophages”. The researcher immediately considered using them to treat bacterial infections, and in 1919, he treated a patient suffering from dysentery: phagotherapy was born.

But what was behind these bacteria killers?

It was not until the 1940s that bacteriophages were observed with an electron microscope. Molecular biology then made it possible to discover that they were encapsidated viruses that only attacked bacteria in a very specific and targeted manner. Moreover, it turned out that bacteriophages can be found in all biotopes, even more so if the environment is rich in bacteria, such as soil or sewage. The latter are nowadays privileged places of supply for researchers.

But why has the use of phagotherapy not become more widespread?

To understand this, let’s go back to the 1930s, when the first antibiotics were developed. The widespread use of these very effective molecules in the Western world simply made bacteriophages fall into oblivion…
Today, due to the uncontrolled use of antibiotics, we must face the challenge of antibiotic resistance. The identification of alternative therapies is therefore essential, and it is quite natural that we are once again turning our attention to phagotherapy. Thus, more than a hundred years after their discovery, bacteriophages will finally be able to play their role and express their full potential, providing humanity with a way to avoid returning to a pre-antibiotic era with disastrous consequences.