One day, a Médecins Sans Frontières camp just 100m away from his small lab was destroyed by a mob.

“It was very frightening but we had to carry on trying to sequence our samples,” says Dr Moussa Diagne. “We heard about World Health Organization staff being shot. It was incredibly scary. But ever since I was studying, we have had our credo – we need to be here for our people. That’s why I didn’t hesitate. We have to concentrate on doing our job.”

But emergency response is just one part of the Institut’s work fighting nasty diseases. Take yellow fever, which leaves patients’ skin a pallid, jaundiced yellow and killed millions during the 19th and 20th centuries. Now, the disease has largely slipped from our memories.

This is partly because scientists at the Institut Pasteur de Dakar developed an effective vaccine, first by injecting the pathogen into mice brains and later by breeding it in sterilised chicken eggs. Today, they are one of only four places on earth to still produce the shot, keeping a watchful eye in case the sleeping epidemic rears its head again.

The Institut Pasteur also jumped to action when the Covid-19 emerged, shifting its focus to pandemic response. Suddenly Senegal was on the frontline, along with Africa’s most industrialised nation South Africa, frantically helping dozens of other countries in the region prepare for the virus.