When he bought the pretty little striped field mouse on the internet for $8 to give to his daughter for her sixth birthday, the businessman from São Paulo was told it was free of infection and had been bred by a registered dealer. In fact, it had been sourced from the vast sugar cane fields planted in Brazil to grow biofuels to reduce the use of fossil fuels – and which were swarming with rodents after yet another heatwave.
It nipped his daughter on the finger, but no one thought much of it – and six days later, he left on a trip to Europe. By the time he reached Amsterdam, she had started suffering fevers, muscle aches and breathing problems and had been rushed to hospital, and he too felt unwell. It was the start of one of the worst pandemics in human history, killing more people than Covid-19, Sars or the 1918 flu pandemic put together.