The subject of vaccination returns to the fore with the coronavirus.

The doctor in virology Tania Louis told the origin of this major scientific discovery, Tuesday in the program "Sans Rendez-vous" on Europe 1.

As the coronavirus epidemic continues to spread, great hope has been born around the world with the announcements by Pfizer (along with BioNTech) and Moderna laboratories of two vaccines that are over 90% effective.

But vaccination, widely used today, is not a scientific method that has only been developed very recently.

The doctor in virology Tania Louis recounted its origin, which dates back to the 18th century, on Tuesday, in the program Sans rendez-vous on Europe 1.

>> Find all of Sans rendez-vous in replay and podcast here

Variolation: injecting ... pus from sick people to healthy people

We must first go back to the 18th century, to a time when smallpox was raging throughout Europe.

"At the start of the 18th century, smallpox was much worse than the coronavirus. It affected a lot of people and killed two-thirds of them, while the survivors often had lesions on their faces. It was a plague of that time," recalls Tania Louis, when smallpox was declared eradicated by the WHO in 1980.

"Everything was good to reduce its impact. A British writer, Mary Wortley Montagu, brought back to Europe an unsavory technique that existed in Turkey and which involved using pus from sick people to inoculate it into healthy people."

This technique, as amazing as it may seem, quickly got results.

"By doing that, there were a lot less deaths, people died less from this voluntary inoculation than from the disease if they caught it afterwards. But it was risky," says Tania Louis.

We are not yet talking of vaccination but then of 'variolation'.

Cows, central to the discovery of vaccination

A few decades later, in the 1790s, the English scientist Edward Jenner made a discovery which made him the "father" of vaccination.

"He realized that people who worked with cows never got smallpox because they had another disease, harmless to humans, called 'vaccine'," continues Tania Louis.

Edward Jenner came up with the idea of ​​using this cow virus by purposely inoculating it into humans to prevent them from getting smallpox. That's how we went from smallpox to vaccination. The word 'vaccine' actually comes from a cow virus. "

Then, gradually, vaccination became a recognized scientific method, before spreading throughout the world.