When I was a child, my family would often go on hikes across Dartmoor, that glorious hilly wilderness in the south-west of England. One of my favourite pastimes on these trips was spotting the ruins of old villages, tucked under heather; these, I was told, were settlements that had been abandoned in the 14th century when the Black Death swept through Europe, killing between 30 per cent and 60 per cent of the population.

It was a haunting memory; so much so that when I recently took one of my daughters riding in the same hills, I pointed out the stones and explained they were a small monument to the horrors of pandemics.