The flu vaccination campaign begins Tuesday, everywhere in France. To develop this vaccine, the pharmaceutical group uses eggs in its factory located in Normandy.
Every day, eggs are delivered by three trucks to the Sanofi factory in Val-de-Reuil, Normandy. These 650,000 eggs are not dedicated to the pharmaceutical company’s canteen to make a giant omelette in the canteen, but are intended for laboratories. After carefully making a small hole in each egg, the flu virus is grown inside. “Into these eggs, we inoculated the flu virusexplains Henri Lanfry, the director of the factory. For four days the virus multiplied and so we have a lot of flu viruses in these eggs, the white of the egg.”
The winter flu vaccination campaign begins Tuesday October 17. French people most at risk, pregnant women, elderly or sick people, are invited to be vaccinated. According to the Ministry of Health, flu vaccination prevents 2,000 deaths each winter. The largest supplier of influenza vaccines in the world is the French laboratory Sanofi.
“Extremely specific eggs”
The process of cultivating the virus in a chicken egg and incubating it may seem artisanal in the age of messenger RNA. “This is the most reliable method and allows us to develop a large quantity of vaccinesexplains Thomas Triomphe, vice-president of Sanofi. The egg turns out to be a preferred environment for the virus. It allows you to have a hemagglutinin, that is to say the key to vaccination in perfect health, in good condition and which allows a strong immune response.”
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Once enough virus has been grown in the egg white, the eggs are filtered and purified. The machines then only recover the virus. Then rendered harmless, it is used to make the vaccine. It seems simple, like a simple baking recipe, but it is impossible to reproduce it at home. First of all, eggs are not the same as those consumed every day. “These are extremely specific eggs, they are ‘pharma’ eggsdetails Henri Lanfry, that is, they have a specific provenance, the chickens have a specific genetic lineage. They have a specific growth pattern and age, and each egg will be checked and rechecked. It’s a far cry from the eggs you’ll find in stores.”
These chicken eggs come from a network of partner farms throughout France. And since we cannot make a vaccine without breaking eggs, the waste, the white, the yolk and the shells are recycled through a methanization process. And are thus used to heat the nearby municipal swimming pool.
How is the flu vaccine made? – Solenne Le Hen